# Occurrence of Major Local Lower Limb Events in Type 2 Diabetic Patients with Lower Extremity Arterial Disease: Impact of Metformin

Shanon Tan, Guillaume Goudot, Armelle Arnoux, Yohann Tran, Hassan Maissoro, Géraldine Poenou, Grégoire Detriche, Lina Khider, Nassim Mohamedi, Tristan Mirault, et al.

► To cite this version:

Shanon Tan, Guillaume Goudot, Armelle Arnoux, Yohann Tran, Hassan Maissoro, et al. Occurrence of Major Local Lower Limb Events in Type 2 Diabetic Patients with Lower Extremity Arterial Disease: Impact of Metformin. Annals of Vascular Surgery, 2023, 90, pp.153-161. 10.1016/j.avsg.2022.09.064. hal-04343656

HAL Id: hal-04343656

https://hal.science/hal-04343656

Submitted on 5 Apr 2024

HAL is a multi-disciplinary open access
archive for the deposit and dissemination of sci-
entific research documents, whether they are pub-
lished or not. The documents may come from
teaching and research institutions in France or
abroad, or from public or private research centers.

L'archive ouverte pluridisciplinaire HAL, est
destinée au dépôt et à la diffusion de documents
scientifiques de niveau recherche, publiés ou non,
émanant des établissements d'enseignement et de
recherche français ou étrangers, des laboratoires
publics ou privés.

<figure><img src="image_1.png" /></figure>

Distributed under a Creative Commons Attribution 4.0 International License
1

Occurrence of major local lower limb events in type

2

2 diabetic patients with lower extremity arterial

3

disease: impact of metformin

4

Shanon TAN¹, Guillaume GOUDOT¹,², Armelle ARNOUX³, Yohann TRAN³, Hassan

5

MAISSORO³, Géraldine POENOU⁴, Grégoire DETRICHE¹,², Lina KHIDER¹,², Nassim

6

MOHAMEDI¹,², Tristan MIRAULT¹,², Alexandre GALLOULA¹, Emmanuel MESSAS¹,²

7

8

1. Vascular medicine department, Georges Pompidou European Hospital, Assistance Publique - Hôpitaux de Paris, France

9

10

2. Université de Paris, INSERM U970 PARCC, Paris, France

11

3. Unité de Recherche Clinique, Assistance Publique - Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Université de Paris, Paris, France.

12

13

4. Internal medicine department, Louis Mourier hospital, Assistance Publique - Hôpitaux de Paris, Université de Paris, Paris, France

14

15

16

Corresponding author : Guillaume GOUDOT, MD, Ph.D., FESC

17

Service de médecine vasculaire, hôpital européen Georges Pompidou;

18

20 rue Leblanc, 75015 Paris, France

19

Mail: guillaume.goudot@aphp.fr

20

21

Keywords: Peripheral artery disease, Diabetes mellitus, Major adverse limb events –
Atherosclerosis, metformin

22

23

24

Number of words: Manuscript: 2853. Abstract: 242.

25
1

# Occurrence of major local lower limb events in type

2

## 2 diabetic patients with lower extremity arterial

3

## disease: impact of metformin

4

Shanon TAN¹, Guillaume GOUDOT¹,², Armelle ARNOUX³, Yohann TRAN³, Hassan

5

MAISSORO³, Géraldine POENOU⁴, Grégoire DETRICHE¹,², Lina KHIDER¹,², Nassim

6

MOHAMEDI¹,², Tristan MIRAULT¹,², Alexandre GALLOULA¹, Emmanuel MESSAS¹,²

7

8

1. Vascular medicine department, Georges Pompidou European Hospital, Assistance Publique - Hôpitaux de Paris, France

9

10

2. Université de Paris, INSERM U970 PARCC, Paris, France

11

3. Unité de Recherche Clinique, Assistance Publique - Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Université de Paris, Paris, France.

12

13

4. Internal medicine department, Louis Mourier hospital, Assistance Publique - Hôpitaux de Paris, Université de Paris, Paris, France

14

15

16

Corresponding author: Guillaume GOUDOT, MD, Ph.D., FESC

17

Service de médecine vasculaire, hôpital européen Georges Pompidou;

18

20 rue Leblanc, 75015 Paris, France

19

Mail: guillaume.goudot@aphp.fr

20

21

Keywords: Peripheral artery disease, Diabetes mellitus, Major adverse limb events - Atherosclerosis, metformin

22

23

24

Number of words: Manuscript: 2853. Abstract: 242.

25
26

# Article Highlights

27

**Type of Research:**

28

Single center retrospective study of prospectively collected registry data (Registry:

29

DIAPA (DIAbetes and Peripheral Artery disease).

30

31

**Key Findings:**

32

Investigation of predictive factors for Major Adverse Limb events in a population of 100

33

diabetic patients with peripheral arterial disease identified Metformin as a protective

34

agent (OR=0.26; 95%CI [0.10; 0.68]; p=0.007).

35

36

**Take home Message:**

37

Metformin protects against local complications in people with diabetes with PAD and

38

should be prescribed in all diabetic patients with peripheral artery disease at an early

39

stage.
26

# Article Highlights

27

## Type of Research:

28

Single center retrospective study of prospectively collected registry data (Registry:

29

DIAPA (DIAbetes and Peripheral Artery disease).

30

31

## Key Findings:

32

Investigation of predictive factors for Major Adverse Limb events in a population of 100

33

diabetic patients with peripheral arterial disease identified Metformin as a protective

34

agent (OR=0.26; 95%CI [0.10; 0.68]; p=0.007).

35

36

## Take home Message:

37

Metformin protects against local complications in people with diabetes with PAD and

38

should be prescribed in all diabetic patients with peripheral artery disease at an early

39

stage.
40

**Abstract**

41

42

43

44

45

46

**Introduction:** patients with type 2 diabetes mellitus (T2DM) are particularly at risk of developing major cardiovascular events (MACE) and peripheral artery disease (PAD) due to an acceleration of the atherosclerotic process linked to hyperglycemia and inflammation with a greater risk of local complications. We aimed to identify the predictive factors for major adverse limb events (MALE) in T2DM patients with PAD to manage modifiable factors at an early stage.

47

48

49

**Methods:** This is a prospective study in which T2DM patients with PAD were included from November 2017 to May 2018 and followed over 12 months. The predictive factors for the onset of MALE, MACE, and death from all causes have been identified.

50

**Results:** a total of 100 patients were included; 37% of the patients developed a MALE. After multivariate analysis, metformin was associated with a decrease of MALE (OR=0.26; 95%CI [0.10; 0.68]; p=0.007), and a history of the treatment of intravenous iloprost was associated with an increased risk of MALE (OR=5.70; 95%CI [1.31; 31.92]; p =0.029). Regular physical activity was associated with a decreased risk of MACE (OR=0.07; 95%CI [0;0.44]; p=0.021). A history of stroke and a history of venous thromboembolism were associated with an increased all-cause mortality risk with OR=3.68; 95%CI [1.17;11.5]; p=0.025 and OR=3.78; 95%CI [1.16; 12.3]; p=0.027.

51

52

53

54

55

56

57

58

**Conclusion:** Metformin is protective against local complications in people with diabetes with PAD and should be prescribed to all diabetic patients with PAD at an early stage.

59

60
40

**Abstract**

41

42

43

44

45

46

**Introduction:** patients with type 2 diabetes mellitus (T2DM) are particularly at risk of developing major cardiovascular events (MACE) and peripheral artery disease (PAD) due to an acceleration of the atherosclerotic process linked to hyperglycemia and inflammation with a greater risk of local complications. We aimed to identify the predictive factors for major adverse limb events (MALE) in T2DM patients with PAD to manage modifiable factors at an early stage.

47

48

49

**Methods:** This is a prospective study in which T2DM patients with PAD were included from November 2017 to May 2018 and followed over 12 months. The predictive factors for the onset of MALE, MACE, and death from all causes have been identified.

50

51

52

53

54

55

56

57

**Results:** a total of 100 patients were included; 37% of the patients developed a MALE. After multivariate analysis, metformin was associated with a decrease of MALE (OR=0.26; 95%CI [0.10; 0.68]; p=0.007), and a history of the treatment of intravenous iloprost was associated with an increased risk of MALE (OR=5.70; 95%CI [1.31; 31.92]; p =0.029). Regular physical activity was associated with a decreased risk of MACE (OR=0.07; 95%CI [0;0.44]; p=0.021). A history of stroke and a history of venous thromboembolism were associated with an increased all-cause mortality risk with OR=3.68; 95%CI [1.17;11.5]; p=0.025 and OR=3.78; 95%CI [1.16; 12.3]; p=0.027.

58

59

**Conclusion:** Metformin is protective against local complications in people with diabetes with PAD and should be prescribed to all diabetic patients with PAD at an early stage.

60
61

# I. Introduction

The number of adults with Type 2 diabetes mellitus (T2DM) has doubled worldwide in the past 30 years and continues to grow exponentially. In 2019 more than 463 million people had DM, representing 9.3% of the world's population, and projections by 2045 estimate that the number of DM patients will reach 700 million by 2045, with 90% of T2DM¹. In 2017, 5 million deaths were attributed to T2DM, and this health burden is mainly due to the cardiovascular complications of the disease. DM is among the top ten causes of death worldwide associated with cardiovascular mortality ²,³. The pathophysiology of diabetic vasculopathy is particularly complex and multifactorial. It combines vascular aggression, especially at the endothelial level, and inhibition of cellular defense or repair mechanisms related to hyperglycemia and inflammation ⁴. This accelerates the atherosclerotic processes, leading to a more advanced, more extensive, and therefore more severe disease. T2DM is a major independent cardiovascular risk factor, doubling or tripling the risk of a cardiovascular event independently of other frequently associated risk factors⁵. The incidence of myocardial infarction is multiplied by 2 to 4 in the case of T2DM and is associated with a higher mortality⁶.

Similarly, the risk of stroke is multiplied by 1.5 to 2 with more severe forms and higher mortality<sup>7,8</sup> and by 5 to 10 for the lower extremity arterial disease (LEAD). LEAD affects 20 to 30% of T2DM patients. Diagnosis in these patients is often delayed due to the T2DM-associated peripheral neuropathy that makes the disease poorly symptomatic. Very often, arterial damage is already advanced at the time of diagnosis. In T2DM, arterial calcifications are extensive and associated with the development of leg ischemia due to arterial obstruction and loss of the capacity to react to vasodilatory stimuli. By adding an increased risk of skin lesion infections due to the altered immunity response
61

# I. Introduction

The number of adults with Type 2 diabetes mellitus (T2DM) has doubled worldwide in the past 30 years and continues to grow exponentially. In 2019 more than 463 million people had DM, representing 9.3% of the world's population, and projections by 2045 estimate that the number of DM patients will reach 700 million by 2045, with 90% of T2DM¹. In 2017, 5 million deaths were attributed to T2DM, and this health burden is mainly due to the cardiovascular complications of the disease. DM is among the top ten causes of death worldwide associated with cardiovascular mortality ²,³. The pathophysiology of diabetic vasculopathy is particularly complex and multifactorial. It combines vascular aggression, especially at the endothelial level, and inhibition of cellular defense or repair mechanisms related to hyperglycemia and inflammation ⁴. This accelerates the atherosclerotic processes, leading to a more advanced, more extensive, and therefore more severe disease. T2DM is a major independent cardiovascular risk factor, doubling or tripling the risk of a cardiovascular event independently of other frequently associated risk factors⁵. The incidence of myocardial infarction is multiplied by 2 to 4 in the case of T2DM and is associated with a higher mortality⁶.

Similarly, the risk of stroke is multiplied by 1.5 to 2 with more severe forms and higher mortality<sup>7,8</sup> and by 5 to 10 for the lower extremity arterial disease (LEAD). LEAD affects 20 to 30% of T2DM patients. Diagnosis in these patients is often delayed due to the T2DM-associated peripheral neuropathy that makes the disease poorly symptomatic. Very often, arterial damage is already advanced at the time of diagnosis. In T2DM, arterial calcifications are extensive and associated with the development of leg ischemia due to arterial obstruction and loss of the capacity to react to vasodilatory stimuli. By adding an increased risk of skin lesion infections due to the altered immunity response
related to the duration and extent of chronic hyperglycemia, T2DM patients are six times more likely to develop Chronic Limb-Threatening Ischemia (CLTI) and 5 to 12 times more likely to undergo major lower limb amputation. In the case of CLTI on one leg, CLTI on the other leg will be diagnosed in 50% of patients ⁹⁻¹¹. In addition, there are more complications after revascularization with higher cardiovascular morbidity ⁹⁻¹². Predictive factors for major lower limb events (MALE) in T2DM patients with LEAD are little known.

Very few studies addressed this question, and the currently known predictive factors of poor local outcomes are the HbA1c level, age, distal artery involvement, renal failure, active smoking, insulin dependence, popliteal stenosis, and a history of a diabetic wound, peripheral revascularization, and amputation or leg ulcer¹³⁻¹⁷. In this study, we aimed to prospectively evaluate the known predictive factors for major local lower limb events (MALE: major adverse limb events: critical ischemia leading to major amputation or revascularization) in type 2 diabetic patients with PAD. We also wished to assess the impact of patient treatment, in particular oral antidiabetic drugs, on the occurrence of MALE, major adverse cardiovascular events (MACE), and all-cause mortality in this population.

## II. Methods

### a. Population

The study was conducted in the Vascular Medicine Department, the Vascular Rehabilitation Department of the Georges-Pompidou European hospital, and Corentin-Celton hospital (Paris). DIAPA (DIAbetes and Peripheral Artery disease) is a prospective registry including patients with T2DM and LEAD. Patients under 18 years of age or with non-type 2 DM are not included in this registry. LEAD is defined by an ankle-brachial
related to the duration and extent of chronic hyperglycemia, T2DM patients are six times more likely to develop Chronic Limb-Threatening Ischemia (CLTI) and 5 to 12 times more likely to undergo major lower limb amputation. In the case of CLTI on one leg, CLTI on the other leg will be diagnosed in 50% of patients ⁹⁻¹¹. In addition, there are more complications after revascularization with higher cardiovascular morbidity ⁹⁻¹². Predictive factors for major lower limb events (MALE) in T2DM patients with LEAD are little known.

Very few studies addressed this question, and the currently known predictive factors of poor local outcomes are the HbA1c level, age, distal artery involvement, renal failure, active smoking, insulin dependence, popliteal stenosis, and a history of a diabetic wound, peripheral revascularization, and amputation or leg ulcer¹³⁻¹⁷. In this study, we aimed to prospectively evaluate the known predictive factors for major local lower limb events (MALE: major adverse limb events: critical ischemia leading to major amputation or revascularization) in type 2 diabetic patients with PAD. We also wished to assess the impact of patient treatment, in particular oral antidiabetic drugs, on the occurrence of MALE, major adverse cardiovascular events (MACE), and all-cause mortality in this population.

## II. Methods

### a. Population

The study was conducted in the Vascular Medicine Department, the Vascular Rehabilitation Department of the Georges-Pompidou European hospital, and Corentin-Celton hospital (Paris). DIAPA (DIAbetes and Peripheral Artery disease) is a prospective registry including patients with T2DM and LEAD. Patients under 18 years of age or with non-type 2 DM are not included in this registry. LEAD is defined by an ankle-brachial
index (ABI) < 0.9, or either a history of endovascular or surgical lower extremity revascularization or the presence of atherosclerotic plaque determined by a thickness ≥ 1.5mm on arterial Doppler ultrasound or computed tomography angiography (CTA) of the abdominal aorta or the lower limb arteries.

The local ethical committee waived patient consent, but a non-opposition for using their medical data is required to include a patient in DIAPA. Biological and clinical parameters were collected at the date of inclusion, including the stage of LEAD and concomitant treatments. Follow-up visits at 6 and 12 months were scheduled. At each visit, the occurrence of MACE (myocardial infarction, stroke, or cardiovascular death), MALE (CLTI leading to revascularization of a lower limb, or major amputation), minor amputations, all-cause death, microvascular complications of T2DM and treatment changes since the last visit were collected in a standardized electronic record (Redcap®, USA). The primary outcome of this study was the occurrence of MALE at the last follow-up. Secondary outcomes were the occurrence of MACE and death from any cause at the last follow-up. Based on the data collected at baseline and the history, we identified predictive factors associated with the presence of MALE at 12 months in these patients with PAD and T2DM. The second objective of this study was to identify factors related to the presence of MACE and the occurrence of all-cause death at 12 months in this population.

## b. Statistical analysis

Results are presented as a mean ± standard deviation or number and frequency (n(%)). The variables analyzed were those at inclusion and the history of patients with less than 20% missing data. There were no patients excluded. In the bivariate analyses, quantitative variables were compared between patients with or without MALE/MACE/death using a Student's T-test if the distribution was normal and a Mann-
index (ABI) < 0.9, or either a history of endovascular or surgical lower extremity revascularization or the presence of atherosclerotic plaque determined by a thickness ≥ 1.5mm on arterial Doppler ultrasound or computed tomography angiography (CTA) of the abdominal aorta or the lower limb arteries.

The local ethical committee waived patient consent, but a non-opposition for using their medical data is required to include a patient in DIAPA. Biological and clinical parameters were collected at the date of inclusion, including the stage of LEAD and concomitant treatments. Follow-up visits at 6 and 12 months were scheduled. At each visit, the occurrence of MACE (myocardial infarction, stroke, or cardiovascular death), MALE (CLTI leading to revascularization of a lower limb, or major amputation), minor amputations, all-cause death, microvascular complications of T2DM and treatment changes since the last visit were collected in a standardized electronic record (Redcap®, USA). The primary outcome of this study was the occurrence of MALE at the last follow-up. Secondary outcomes were the occurrence of MACE and death from any cause at the last follow-up. Based on the data collected at baseline and the history, we identified predictive factors associated with the presence of MALE at 12 months in these patients with PAD and T2DM. The second objective of this study was to identify factors related to the presence of MACE and the occurrence of all-cause death at 12 months in this population.

## b. Statistical analysis

Results are presented as a mean ± standard deviation or number and frequency (n(%)). The variables analyzed were those at inclusion and the history of patients with less than 20% missing data. There were no patients excluded. In the bivariate analyses, quantitative variables were compared between patients with or without MALE/MACE/death using a Student's T-test if the distribution was normal and a Mann-
135 Whitney test in all cases. When the p-value of the parametric test differed from that of
136 the non-parametric test, the non-parametric p-value was considered for further
137 analyses. Qualitative variables were compared between patients with or without
138 MALE/MACE/death using a Chi-square test and a Fisher test when numbers permitted.

139 Based on this bivariate analysis, we pre-selected the variables associated with the
140 criterion MALE/MACE/death, whose p-value is significant at the 20% threshold.
141 Variables with missing data were not retained.

142 We then proceeded to the final selection of independent variables associated with the
143 presence of MACE/MALE at 12 months by a multivariate analysis based on logistic
144 regression modeling with stepwise variable selection. The results are presented as odds
145 ratio (OR) with a 95% confidence interval (CI). We selected the independent variables
146 that explain the occurrence of all-cause deaths using a Cox proportional risk model with
147 stepwise variable selection. The results are presented as a Hazard Ratio (HR) with a
148 95% CI. Residuals were verified by the Schoenfeld method. The Kaplan-Meier method
149 was used to compare patient survival with/without MACE and with/without MALE. The
150 results for each criterion are shown graphically as Forest plots. Lastly, to avoid a
151 potential confounding bias of no metformin prescription in severe renal failure, we
152 performed a bivariate analysis of the severe renal failure variable at inclusion (M0)
153 between patients who developed MALE vs. Non-MALE during follow-up.

154 III. Results

155 One hundred consecutive patients were included from November 2017 to May 2018.
156 The mean age was 70.9±9.2 years, and men represented 86% of the patients. Table 1
157 presents the characteristics of the patients at inclusion. All patients had hypertension,
158 98% had dyslipidemia, 12% were active smokers and, 49% former smokers, 65% were
135 Whitney test in all cases. When the p-value of the parametric test differed from that of
136 the non-parametric test, the non-parametric p-value was considered for further
137 analyses. Qualitative variables were compared between patients with or without
138 MALE/MACE/death using a Chi-square test and a Fisher test when numbers permitted.

139 Based on this bivariate analysis, we pre-selected the variables associated with the
140 criterion MALE/MACE/death, whose p-value is significant at the 20% threshold.
141 Variables with missing data were not retained.

142 We then proceeded to the final selection of independent variables associated with the
143 presence of MACE/MALE at 12 months by a multivariate analysis based on logistic
144 regression modeling with stepwise variable selection. The results are presented as odds
145 ratio (OR) with a 95% confidence interval (CI). We selected the independent variables
146 that explain the occurrence of all-cause deaths using a Cox proportional risk model with
147 stepwise variable selection. The results are presented as a Hazard Ratio (HR) with a
148 95% CI. Residuals were verified by the Schoenfeld method. The Kaplan-Meier method
149 was used to compare patient survival with/without MACE and with/without MALE. The
150 results for each criterion are shown graphically as Forest plots. Lastly, to avoid a
151 potential confounding bias of no metformin prescription in severe renal failure, we
152 performed a bivariate analysis of the severe renal failure variable at inclusion (M0)
153 between patients who developed MALE vs. Non-MALE during follow-up.

154 III. Results

155 One hundred consecutive patients were included from November 2017 to May 2018.
156 The mean age was 70.9±9.2 years, and men represented 86% of the patients. Table 1
157 presents the characteristics of the patients at inclusion. All patients had hypertension,
158 98% had dyslipidemia, 12% were active smokers and, 49% former smokers, 65% were
159 overweight. The mean duration of diabetes since initial diagnosis was 17.4 years, with a
160 mean HbA1c of 7.3%. There was no difference in glycemic control between patients on
161 metformin and patients without metformin, with HbA1c not significantly different
162 between the two groups: median HbA1c was 7.1% [6.3-8.4] for patients taking
163 metformin vs. 6.8 [6.3-7.6] for patients without metformin (p=0.412).

164 More than half of the patients had at least one microvascular complication of diabetes:
165 79% had diabetic neuropathy (64% of which were complicated by diabetic wounds);
166 41% had diabetic retinopathy (19% of which was at the stage of proliferative
167 retinopathy), and 89% had diabetic nephropathy (54% of which had chronic renal
168 failure defined by a glomerular filtration rate below 60mL/min).

169 The average duration of the PAD was 4.7 years. More than two-thirds of the patients had
170 symptomatic PAD, of which 33% with claudication and 67% had critical ischemia (96%
171 leg ulcer or necrosis). 39% had already had at least one hospitalization for a PAD. 35%
172 had already had a history of healed critical ischemia. 75% had already been
173 revascularized by surgery or angioplasty, and 42% had been amputated, of which 6%
174 were major amputations. 12% had had at least one treatment with venous iloprost in
175 the past.

176 Regarding treatment, 78% of patients were on triple vasculoprotective therapy with an
177 ACE inhibitor or ARA2 in combination with a statin (95%) and an antiplatelet agent
178 (mainly aspirin in 90%) (Supplementary data).

179 66% of patients were on oral anti-diabetic drugs (OADs), mainly metformin (56%), and
180 58% were on insulin alone or in combination with OADs.

181 All the cardiovascular events that occurred during the follow-up period, the first six
182 months and up to 1 year, are presented in Table 2. At 12 months of follow-up, among the
183 patients alive, 44% had critical ischemia, with 3% at stage III and 41% at stage IV of the
159 overweight. The mean duration of diabetes since initial diagnosis was 17.4 years, with a
160 mean HbA1c of 7.3%. There was no difference in glycemic control between patients on
161 metformin and patients without metformin, with HbA1c not significantly different
162 between the two groups: median HbA1c was 7.1% [6.3-8.4] for patients taking
163 metformin vs. 6.8 [6.3-7.6] for patients without metformin (p=0.412).

164 More than half of the patients had at least one microvascular complication of diabetes:
165 79% had diabetic neuropathy (64% of which were complicated by diabetic wounds);
166 41% had diabetic retinopathy (19% of which was at the stage of proliferative
167 retinopathy), and 89% had diabetic nephropathy (54% of which had chronic renal
168 failure defined by a glomerular filtration rate below 60mL/min).

169 The average duration of the PAD was 4.7 years. More than two-thirds of the patients had
170 symptomatic PAD, of which 33% with claudication and 67% had critical ischemia (96%
171 leg ulcer or necrosis). 39% had already had at least one hospitalization for a PAD. 35%
172 had already had a history of healed critical ischemia. 75% had already been
173 revascularized by surgery or angioplasty, and 42% had been amputated, of which 6%
174 were major amputations. 12% had had at least one treatment with venous iloprost in
175 the past.

176 Regarding treatment, 78% of patients were on triple vasculoprotective therapy with an
177 ACE inhibitor or ARA2 in combination with a statin (95%) and an antiplatelet agent
178 (mainly aspirin in 90%) (Supplementary data).

179 66% of patients were on oral anti-diabetic drugs (OADs), mainly metformin (56%), and
180 58% were on insulin alone or in combination with OADs.

181 All the cardiovascular events that occurred during the follow-up period, the first six
182 months and up to 1 year, are presented in Table 2. At 12 months of follow-up, among the
183 patients alive, 44% had critical ischemia, with 3% at stage III and 41% at stage IV of the
184 Fontaine classification. 22% of the patients had an asymptomatic PAD, and 34% had
185 intermittent claudication. During this follow-up, the total occurrence of MALE was 37%,
186 lower limb revascularization 36%, and major amputation 4%.

187 Among the patients who had a MALE during follow-up, 97.3% were revascularized for
188 critical ischemia, 10.8% had a major amputation, 29.7% had a minor amputation, and
189 16% had a MACE. Patients with a MALE did not die more than non-MALE and did not
190 have more MACE (Table 3).

191 MACE, myocardial infarction, ischemic stroke, and cardiovascular death were
192 respectively 13%, 6%, 1%, and 10% when considering deaths secondary to
193 complications related to the PAD itself. Among the patients with MACE, 46% had MI,
194 7.7% had a stroke, 77% had cardiovascular death, and 46% had a MALE. Patients who
195 developed a MACE during follow-up did not have more MALE (Table 4).

196 At the end of the follow-up, 14% of the patients had died, with 71.4% from
197 cardiovascular causes. 71% of these patients had presented a MACE, 21% a MI, and 35%
198 a MALE. Patients who died did not have more MALE during follow-up than patients who
199 were still alive (Supplementary data).

200 a. Factors associated with the occurrence of MALE

201 During the one-year follow-up, 37% of the patients had experienced a MALE. After
202 multivariate analysis, the independent factors associated with the occurrence of MALE
203 at one year were the following (Figure 1):

204 - The use of metformin and the history of intravenous iloprost treatment. Metformin
205 appeared to be a protective factor against the occurrence of MALE with an Odds Ratio
206 (OR) of 0.26; 95%CI [0.10;0.68] (p=0.007). Characteristics of patients with metformin
207 vs. without metformin are provided in supplementary data.
184 Fontaine classification. 22% of the patients had an asymptomatic PAD, and 34% had
185 intermittent claudication. During this follow-up, the total occurrence of MALE was 37%,
186 lower limb revascularization 36%, and major amputation 4%.

187 Among the patients who had a MALE during follow-up, 97.3% were revascularized for
188 critical ischemia, 10.8% had a major amputation, 29.7% had a minor amputation, and
189 16% had a MACE. Patients with a MALE did not die more than non-MALE and did not
190 have more MACE (Table 3).

191 MACE, myocardial infarction, ischemic stroke, and cardiovascular death were
192 respectively 13%, 6%, 1%, and 10% when considering deaths secondary to
193 complications related to the PAD itself. Among the patients with MACE, 46% had MI,
194 7.7% had a stroke, 77% had cardiovascular death, and 46% had a MALE. Patients who
195 developed a MACE during follow-up did not have more MALE (Table 4).

196 At the end of the follow-up, 14% of the patients had died, with 71.4% from
197 cardiovascular causes. 71% of these patients had presented a MACE, 21% a MI, and 35%
198 a MALE. Patients who died did not have more MALE during follow-up than patients who
199 were still alive (Supplementary data).

200 a. Factors associated with the occurrence of MALE

201 During the one-year follow-up, 37% of the patients had experienced a MALE. After
202 multivariate analysis, the independent factors associated with the occurrence of MALE
203 at one year were the following (Figure 1):

204 - The use of metformin and the history of intravenous iloprost treatment. Metformin
205 appeared to be a protective factor against the occurrence of MALE with an Odds Ratio
206 (OR) of 0.26; 95%CI [0.10;0.68] (p=0.007). Characteristics of patients with metformin
207 vs. without metformin are provided in supplementary data.
208 - A history of intravenous iloprost treatment appeared to be a risk factor for the
209 occurrence of MALE with an OR of 5.70 95%CI [1.31; 31.92] (p=0.029).

210 Critical ischemia stage 4 at M0 was associated with an increase in MALE but not
211 significantly, with an OR of 3.24 95%CI [0.94;13.26] and a p=0.076. Severe renal failure
212 was not related to the occurrence of MALE in neither bivariate (p=0.132) nor
213 multivariate analysis (OR=0.73; 95%CI [0.26;2.07] p=0.620.

214 **b. Factors associated with the occurrence of MACE**

215 During the one-year follow-up, 13% of the patients had developed a MACE.

216 The factors identified as being associated with the occurrence of MACE at one year in a
217 bi-variate analysis at the significance level (p<0.05) were as follows:

218 - Presence of a trophic disorder at inclusion (p=0.014): among patients who had a MACE
219 at one year, 92.3% had a lower limb ulcer or necrosis at inclusion vs. 56.32% among
220 patients without a MACE at one year

221 - Regular physical activity (p=0.003): 51.7% of patients without MACE were active
222 versus 7.7% of patients with MACE at one year

223 After multivariate analysis, only one independent factor associated with the occurrence
224 of MACE at the significance level of p<0.05 was identified (Supplementary figure):
225 regular physical activity with an OR of 0.066 (p=0.021), appearing to be a protective
226 factor against the occurrence of MACE throughout the follow-up.

227 **c. Factors associated with the occurrence of death from any cause at one year**

229 During the one-year follow-up, 14 patients died for any reason. The factors identified as
230 being related to the event of death from any cause at one year in bi-variate analysis at
231 the significance level of p<0.05 were:
208 - A history of intravenous iloprost treatment appeared to be a risk factor for the
209 occurrence of MALE with an OR of 5.70 95%CI [1.31; 31.92] (p=0.029).

210 Critical ischemia stage 4 at M0 was associated with an increase in MALE but not
211 significantly, with an OR of 3.24 95%CI [0.94;13.26] and a p=0.076. Severe renal failure
212 was not related to the occurrence of MALE in neither bivariate (p=0.132) nor
213 multivariate analysis (OR=0.73; 95%CI [0.26;2.07] p=0.620.

214 **b. Factors associated with the occurrence of MACE**

215 During the one-year follow-up, 13% of the patients had developed a MACE.

216 The factors identified as being associated with the occurrence of MACE at one year in a
217 bi-variate analysis at the significance level (p<0.05) were as follows:

218 - Presence of a trophic disorder at inclusion (p=0.014): among patients who had a MACE
219 at one year, 92.3% had a lower limb ulcer or necrosis at inclusion vs. 56.32% among
220 patients without a MACE at one year

221 - Regular physical activity (p=0.003): 51.7% of patients without MACE were active
222 versus 7.7% of patients with MACE at one year

223 After multivariate analysis, only one independent factor associated with the occurrence
224 of MACE at the significance level of p<0.05 was identified (Supplementary figure):
225 regular physical activity with an OR of 0.066 (p=0.021), appearing to be a protective
226 factor against the occurrence of MACE throughout the follow-up.

227 **c. Factors associated with the occurrence of death from any cause at one year**

229 During the one-year follow-up, 14 patients died for any reason. The factors identified as
230 being related to the event of death from any cause at one year in bi-variate analysis at
231 the significance level of p<0.05 were:
1. Age: patients who died during follow-up were older (75±10 years vs. 70±9 years on average) (p=0.046).

2. A reason for hospitalization for treatment of a lower limb wound; the other reasons were a follow-up of PAD without trophic disorder and follow-up of diabetes. All patients who died were hospitalized for a lower limb wound vs. 58.1% of patients still alive at one year (p=0.003).

3. The Fontaine classification stage of PAD at inclusion (p=0.021): patients who died at one year had stage IV at inclusion in 85.7% of cases vs. 46% of patients alive at one year.

4. Presence of any kind of leg wound (p=0.001): 100% of patients who died had a wound at inclusion vs. 54.7% of patients alive at one year

5. Physical activity (p=0.018): 14.3% of the deceased patients practiced regular physical activity at inclusion vs. 51.2% of patients alive at one year

6. A history of stroke (p=0.03): 35.7% of the deceased patients had a history of stroke versus 12.8% of the patients still alive at one year

7. A history of venous thrombo-embolic event (VTE) (p=0.032): 28.6% of patients who died had a history of VTE versus 6.9% of patients still alive at one year

8. OAD use (p=0.049): 42.9% of deceased patients were on OAD at inclusion vs. 69.8% of living patients.

After multivariate analysis, the independent factors associated with the occurrence of all-cause death at one year at the significance level were:

1. A history of VTE (p=0.027) with an HR of 3.8; 95%CI [1.16; 12.3]

2. A history of stroke (p=0.025) with an HR of 3.7; 95%CI [1.17;11.50]

However, a history of CTLI was not significantly associated with a decrease in all-cause mortality but with a trend towards a higher mortality rate (p=0.074). Figure 2 shows the Forest plot of the independent factors related to all-cause death. Patients with MALE
1. Age: patients who died during follow-up were older (75±10 years vs. 70±9 years on average) (p=0.046).

2. A reason for hospitalization for treatment of a lower limb wound; the other reasons were a follow-up of PAD without trophic disorder and follow-up of diabetes. All patients who died were hospitalized for a lower limb wound vs. 58.1% of patients still alive at one year (p=0.003).

3. The Fontaine classification stage of PAD at inclusion (p=0.021): patients who died at one year had stage IV at inclusion in 85.7% of cases vs. 46% of patients alive at one year.

4. Presence of any kind of leg wound (p=0.001): 100% of patients who died had a wound at inclusion vs. 54.7% of patients alive at one year

5. Physical activity (p=0.018): 14.3% of the deceased patients practiced regular physical activity at inclusion vs. 51.2% of patients alive at one year

6. A history of stroke (p=0.03): 35.7% of the deceased patients had a history of stroke versus 12.8% of the patients still alive at one year

7. A history of venous thrombo-embolic event (VTE) (p=0.032): 28.6% of patients who died had a history of VTE versus 6.9% of patients still alive at one year

8. OAD use (p=0.049): 42.9% of deceased patients were on OAD at inclusion vs. 69.8% of living patients.

After multivariate analysis, the independent factors associated with the occurrence of all-cause death at one year at the significance level were:

1. A history of VTE (p=0.027) with an HR of 3.8; 95%CI [1.16; 12.3]

2. A history of stroke (p=0.025) with an HR of 3.7; 95%CI [1.17;11.50]

However, a history of CTLI was not significantly associated with a decrease in all-cause mortality but with a trend towards a higher mortality rate (p=0.074). Figure 2 shows the Forest plot of the independent factors related to all-cause death. Patients with MALE
257 during follow-up did not die more than those without MALE at the end of follow-up, with
258 13.5% and 14.3% of deaths for MALE and non-MALE with a p=0.914 at the end of
259 follow-up.

260 **IV. Discussion**

261 We aimed to identify and assess the predictive factors for major local events of the lower
262 limbs during a 12-month follow-up in a population of T2DM patients with PAD. At the
263 end of the 12-month follow-up, metformin was associated with a decrease in MALE and
264 appeared to be a protective factor with an OR=0.2. Few studies have looked at the
265 predictive factors for the progression of PAD, and even fewer in this population. Most
266 studies were interventional studies comparing intensive vs. conventional glycemic
267 control or different management of cardiovascular risk factors (hypertension,
268 dyslipidemia) on the occurrence of MACE and microvascular complications with little
269 data on macrovascular damage to the lower limb <sup>3,18-21</sup>.

270 In the UKPDS 34 study in newly diagnosed T2DM diabetes patients with no prior
271 cardiovascular history over a 10-year follow-up, metformin was associated with a 32%
272 reduction in the risk of diabetes-related events, including lower limb amputations, a
273 36% reduction in the risk of all-cause death. Regarding macrovascular events (MI,
274 sudden death, PAD, stroke), metformin reduced the risk by 30% compared to
275 conventional treatment <sup>18,22</sup>. Similar results were found in the HOME randomized trial of
276 insulin-requiring T2DM patients, comparing treatment with metformin + insulin vs.
277 placebo + insulin during a 4-year follow-up. A 39% reduction in the risk of
278 macrovascular events, including non-traumatic lower limb amputations, was found<sup>23</sup>.
279 Using imaging, metformin is also negatively and independently associated with lower-
280 limb arterial calcification<sup>24</sup>. UKPDS and HOME randomized trials found a decrease in
257 during follow-up did not die more than those without MALE at the end of follow-up, with
258 13.5% and 14.3% of deaths for MALE and non-MALE with a p=0.914 at the end of
259 follow-up.

260 **IV. Discussion**

261 We aimed to identify and assess the predictive factors for major local events of the lower
262 limbs during a 12-month follow-up in a population of T2DM patients with PAD. At the
263 end of the 12-month follow-up, metformin was associated with a decrease in MALE and
264 appeared to be a protective factor with an OR=0.2. Few studies have looked at the
265 predictive factors for the progression of PAD, and even fewer in this population. Most
266 studies were interventional studies comparing intensive vs. conventional glycemic
267 control or different management of cardiovascular risk factors (hypertension,
268 dyslipidemia) on the occurrence of MACE and microvascular complications with little
269 data on macrovascular damage to the lower limb <sup>3,18-21</sup>.

270 In the UKPDS 34 study in newly diagnosed T2DM diabetes patients with no prior
271 cardiovascular history over a 10-year follow-up, metformin was associated with a 32%
272 reduction in the risk of diabetes-related events, including lower limb amputations, a
273 36% reduction in the risk of all-cause death. Regarding macrovascular events (MI,
274 sudden death, PAD, stroke), metformin reduced the risk by 30% compared to
275 conventional treatment <sup>18,22</sup>. Similar results were found in the HOME randomized trial of
276 insulin-requiring T2DM patients, comparing treatment with metformin + insulin vs.
277 placebo + insulin during a 4-year follow-up. A 39% reduction in the risk of
278 macrovascular events, including non-traumatic lower limb amputations, was found<sup>23</sup>.
279 Using imaging, metformin is also negatively and independently associated with lower-
280 limb arterial calcification<sup>24</sup>. UKPDS and HOME randomized trials found a decrease in
281 cardiovascular events and a more significant weight loss associated with metformin.
282 This weight loss potentiates the effect of insulin on its target organs by decreasing the
283 adipose mass and consequently allows a decrease in HbA1c. The HOME trial also
284 demonstrated a reduction in biological markers of inflammation (such as C reactive
285 protein) and markers of endothelial dysfunction such as Tissue Plasminogen Activator
286 or the Plasminogen activator inhibitor 1, which may explain the decrease in major
287 adverse events due to the reduction of atherosclerosis progression in patients taking
288 Metformin.

289 The complex mechanisms by which metformin would have a beneficial effect on
290 macrovascular damage include a decrease in endothelial dysfunction by increasing
291 Nitric oxide production, a reduction of oxidative stress by reducing the production of
292 oxygenated reagents, and advanced glycation products. In addition, metformin lowers
293 triglyceride levels and slows down the atherosclerotic process²⁵. It may be thus
294 worthwhile to prescribe metformin in patients newly diagnosed with type 2 diabetes
295 but also to continue metformin in the absence of severe renal impairment
296 (GFR<30ml/min) even in insulin-dependent patients because of the potentially vascular
297 protection effect of metformin and to potentiate the effects of insulin ²³,²⁶.

298 Limitations

299 The first limitation is the short follow-up period of one year, which did not allow the
detection of sufficient MALE to identify further predictive factors for complications of
300 PAD. In addition, the study included only 100 patients, which may also have prevented
301 the identification of other factors associated with MALE. We were also unable to
302 characterize the severity of PAD due to technical problems in measuring the pressure of
303 the big toes and TcPO2 in patients with arterial calcifications. Similarly, most patients
304 had significant distal medial arterial calcification due to the duration of diabetes and the
305
281 cardiovascular events and a more significant weight loss associated with metformin.
282 This weight loss potentiates the effect of insulin on its target organs by decreasing the
283 adipose mass and consequently allows a decrease in HbA1c. The HOME trial also
284 demonstrated a reduction in biological markers of inflammation (such as C reactive
285 protein) and markers of endothelial dysfunction such as Tissue Plasminogen Activator
286 or the Plasminogen activator inhibitor 1, which may explain the decrease in major
287 adverse events due to the reduction of atherosclerosis progression in patients taking
288 Metformin.

289 The complex mechanisms by which metformin would have a beneficial effect on
290 macrovascular damage include a decrease in endothelial dysfunction by increasing
291 Nitric oxide production, a reduction of oxidative stress by reducing the production of
292 oxygenated reagents, and advanced glycation products. In addition, metformin lowers
293 triglyceride levels and slows down the atherosclerotic process²⁵. It may be thus
294 worthwhile to prescribe metformin in patients newly diagnosed with type 2 diabetes
295 but also to continue metformin in the absence of severe renal impairment
296 (GFR<30ml/min) even in insulin-dependent patients because of the potentially vascular
297 protection effect of metformin and to potentiate the effects of insulin ²³,²⁶.

298 Limitations

299 The first limitation is the short follow-up period of one year, which did not allow the
detection of sufficient MALE to identify further predictive factors for complications of
300 PAD. In addition, the study included only 100 patients, which may also have prevented
301 the identification of other factors associated with MALE. We were also unable to
302 characterize the severity of PAD due to technical problems in measuring the pressure of
303 the big toes and TcPO2 in patients with arterial calcifications. Similarly, most patients
304 had significant distal medial arterial calcification due to the duration of diabetes and the
305
306 presence of renal insufficiency, making complementary imaging examinations
307 challenging to interpret. Nevertheless, the exhaustive nature of the data collection at
308 inclusion and of the history allowed us to confirm the predictive factors already known
309 for the occurrence of MALE but also to identify protective factors such as the use of
310 metformin. Lastly, few patients were on GLP1 analogs (7%) and none on SGLT2
311 inhibitors, preventing our cohort's evaluation of these treatments.

312 Conclusion

313 We have identified and evaluated the predictive factors for the occurrence of MALE in
314 patients with advanced T2DM with arterial disease and at very high cardiovascular risk.
315 Metformin seems to protect against local complications even in people with diabetes
316 with severe arterial disease. Metformin should be prescribed for all diabetic patients
317 with arterial disease and used early after diagnosing PAD. Regular physical activity, 30
318 minutes a day at least three times a week, is associated with reducing major
319 cardiovascular events and should be encouraged and maintained in this population.
306 presence of renal insufficiency, making complementary imaging examinations
307 challenging to interpret. Nevertheless, the exhaustive nature of the data collection at
308 inclusion and of the history allowed us to confirm the predictive factors already known
309 for the occurrence of MALE but also to identify protective factors such as the use of
310 metformin. Lastly, few patients were on GLP1 analogs (7%) and none on SGLT2
311 inhibitors, preventing our cohort's evaluation of these treatments.

312 Conclusion

313 We have identified and evaluated the predictive factors for the occurrence of MALE in
314 patients with advanced T2DM with arterial disease and at very high cardiovascular risk.
315 Metformin seems to protect against local complications even in people with diabetes
316 with severe arterial disease. Metformin should be prescribed for all diabetic patients
317 with arterial disease and used early after diagnosing PAD. Regular physical activity, 30
318 minutes a day at least three times a week, is associated with reducing major
319 cardiovascular events and should be encouraged and maintained in this population.
320 **V. References**

321 1. Saeedi P, Petersohn I, Salpea P, Malanda B, Karuranga S, Unwin N, et al. Global and regional diabetes prevalence estimates for 2019 and projections for 2030 and 2045: Results from the International Diabetes Federation Diabetes Atlas, 9th edition. Diabetes Res Clin Pract. 2019 Nov 1;157:107843.

325 2. Chatterjee S, Khunti K, Davies MJ. Type 2 diabetes. Vol. 389, The Lancet. Lancet; 2017. p. 2239-51.

327 3. Gaede P, Vedel P, Larsen N, Jensen GVHH, Parving H-H, Pedersen O, et al. Multifactorial intervention and cardiovascular disease in patients with type 2 diabetes. N Engl J Med. 2003 Jan 30;348(5):383-93.

330 4. Fowler MJ. Microvascular and macrovascular complications of diabetes. Vol. 26, Clinical Diabetes. American Diabetes Association; 2008. p. 77-82.

332 5. Franco OH, Steyerberg EW, Hu FB, Mackenbach J, Nusselder W. Associations of Diabetes Mellitus With Total Life Expectancy and Life Expectancy With and Without Cardiovascular Disease. 2007 Jun 11;167(11).

335 6. Franklin K, Goldberg RJ, Spencer F, Klein W, Budaj A, Brieger D, et al. Implications of Diabetes in Patients With Acute Coronary Syndromes: The Global Registry of Acute Coronary Events. 2004 Jul 12;164(13).

338 7. Stegmayr B, Asplund K. Diabetes as a risk factor for stroke. A population perspective. Diabetologia. 1995 Sep;38(9).

340 8. Tuomilehto J, Rastenyté D, Jousilahti P, Sarti C, Vartiainen E, Rastenyte D, et al. Diabetes Mellitus as a Risk Factor for Death From Stroke. Stroke. 1996 Feb;27(2).

342 9. Marso SP, Hiatt WR. Peripheral arterial disease in patients with diabetes. Journal of the American College of Cardiology J Am Coll Cardiol; Mar 7, 2006 p. 921-9.

344 10. Jude EB, Eleftheriadou I, Tentolouris N. Peripheral arterial disease in diabetes - A
320 **V. References**

321 1. Saeedi P, Petersohn I, Salpea P, Malanda B, Karuranga S, Unwin N, et al. Global and regional diabetes prevalence estimates for 2019 and projections for 2030 and 2045: Results from the International Diabetes Federation Diabetes Atlas, 9th edition. Diabetes Res Clin Pract. 2019 Nov 1;157:107843.

325 2. Chatterjee S, Khunti K, Davies MJ. Type 2 diabetes. Vol. 389, The Lancet. Lancet; 2017. p. 2239-51.

327 3. Gaede P, Vedel P, Larsen N, Jensen GVHH, Parving H-H, Pedersen O, et al. Multifactorial intervention and cardiovascular disease in patients with type 2 diabetes. N Engl J Med. 2003 Jan 30;348(5):383-93.

330 4. Fowler MJ. Microvascular and macrovascular complications of diabetes. Vol. 26, Clinical Diabetes. American Diabetes Association; 2008. p. 77-82.

332 5. Franco OH, Steyerberg EW, Hu FB, Mackenbach J, Nusselder W. Associations of Diabetes Mellitus With Total Life Expectancy and Life Expectancy With and Without Cardiovascular Disease. 2007 Jun 11;167(11).

335 6. Franklin K, Goldberg RJ, Spencer F, Klein W, Budaj A, Brieger D, et al. Implications of Diabetes in Patients With Acute Coronary Syndromes: The Global Registry of Acute Coronary Events. 2004 Jul 12;164(13).

338 7. Stegmayr B, Asplund K. Diabetes as a risk factor for stroke. A population perspective. Diabetologia. 1995 Sep;38(9).

340 8. Tuomilehto J, Rastenyté D, Jousilahti P, Sarti C, Vartiainen E, Rastenyte D, et al. Diabetes Mellitus as a Risk Factor for Death From Stroke. Stroke. 1996 Feb;27(2).

342 9. Marso SP, Hiatt WR. Peripheral arterial disease in patients with diabetes. Journal of the American College of Cardiology J Am Coll Cardiol; Mar 7, 2006 p. 921-9.

344 10. Jude EB, Eleftheriadou I, Tentolouris N. Peripheral arterial disease in diabetes - A
345

review. Vol. 27, Diabetic Medicine. Diabet Med; 2010. p. 4–14.

346

11.

Thiruvoipati T, Kielhorn CE, Armstrong EJ. Peripheral artery disease in patients with diabetes: Epidemiology, mechanisms, and outcomes. World J Diabetes. 2015

347

348

Jul 10;6(7):961.

349

12.

Clark N. Peripheral Arterial Disease in People with Diabetes. Vol. 26, Diabetes Care. Diabetes Care; 2003. p. 3333–41.

350

351

13.

Eshcol J, Jebarani S, Anjana RM, Mohan V, Pradeepa R. Prevalence, incidence and progression of peripheral arterial disease in Asian Indian type 2 diabetic patients. 2014;28(5).

352

353

354

14.

Meloni M, Izzo V, Giurato L, Gandini R, Uccioli L. Below-the-ankle arterial disease severely impairs the outcomes of diabetic patients with ischemic foot ulcers. 2019 Jun;152:9–15.

355

356

357

15.

Morbach S, Furchert H, Gröblinghoff U, Hoffmeier H, Kersten K, Klauke G-TT, et al. Long-Term Prognosis of Diabetic Foot Patients and Their Limbs: Amputation and death over the course of a decade. 2012 Oct;35(10).

358

359

360

16.

Ghanassia E, Villon L, Thuan Dit Dieudonné J-F, Boegner C, Avignon A, Sultan A, et al. Long- Term Outcome and Disability of Diabetic Patients Hospitalized for Diabetic Foot Ulcers: A 6.5-year follow-up study. 2008 Jul;31(7).

361

362

363

17.

Wilcox T, Newman JD, Maldonado TS, Rockman C, Berger JS. Peripheral vascular disease risk in diabetic individuals without coronary heart disease. Atherosclerosis. 2018;275:419–25.

364

365

366

18.

Turner R. Effect of intensive blood-glucose control with metformin on complications in overweight patients with type 2 diabetes (UKPDS 34). Lancet. 1998 Sep 12;352(9131):854–65.

367

368

369

19.

Turner R. Intensive blood-glucose control with sulphonylureas or insulin
345

review. Vol. 27, Diabetic Medicine. Diabet Med; 2010. p. 4-14.

346

11.

Thiruvoipati T, Kielhorn CE, Armstrong EJ. Peripheral artery disease in patients with diabetes: Epidemiology, mechanisms, and outcomes. World J Diabetes. 2015

347

348

Jul 10;6(7):961.

349

12.

Clark N. Peripheral Arterial Disease in People with Diabetes. Vol. 26, Diabetes Care. Diabetes Care; 2003. p. 3333-41.

350

351

13.

Eshcol J, Jebarani S, Anjana RM, Mohan V, Pradeepa R. Prevalence, incidence and progression of peripheral arterial disease in Asian Indian type 2 diabetic patients. 2014;28(5).

352

353

354

14.

Meloni M, Izzo V, Giurato L, Gandini R, Uccioli L. Below-the-ankle arterial disease severely impairs the outcomes of diabetic patients with ischemic foot ulcers. 2019 Jun;152:9-15.

355

356

357

15.

Morbach S, Furchert H, Gröblinghoff U, Hoffmeier H, Kersten K, Klauke G-TT, et al. Long-Term Prognosis of Diabetic Foot Patients and Their Limbs: Amputation and death over the course of a decade. 2012 Oct;35(10).

358

359

360

16.

Ghanassia E, Villon L, Thuan Dit Dieudonné J-F, Boegner C, Avignon A, Sultan A, et al. Long-Term Outcome and Disability of Diabetic Patients Hospitalized for Diabetic Foot Ulcers: A 6.5-year follow-up study. 2008 Jul;31(7).

361

362

363

17.

Wilcox T, Newman JD, Maldonado TS, Rockman C, Berger JS. Peripheral vascular disease risk in diabetic individuals without coronary heart disease. Atherosclerosis. 2018;275:419-25.

364

365

366

18.

Turner R. Effect of intensive blood-glucose control with metformin on complications in overweight patients with type 2 diabetes (UKPDS 34). Lancet. 1998 Sep 12;352(9131):854-65.

367

368

369

19.

Turner R. Intensive blood-glucose control with sulphonylureas or insulin
compared with conventional treatment and risk of complications in patients with type 2 diabetes (UKPDS 33). Lancet. 1998 Sep 12;352(9131):837-53.

20. Margolis KL, O'Connor PJ, Morgan TM, Buse JB, Cohen RM, Cushman WC, et al. Outcomes of combined cardiovascular risk factor management strategies in type 2 diabetes: the ACCORD randomized trial. Diabetes Care. 2014 Jun;37(6):1721-8.

21. Stratton IM, Adler AI, Neil HAW, Matthews DR, Manley SE, Cull CA, et al. Association of glycaemia with macrovascular and microvascular complications of type 2 diabetes (UKPDS 35): Prospective observational study. Br Med J. 2000 Aug 12;321(7258):405-12.

22. Holman RR, Paul SK, Bethel MA, Matthews DR, Neil HAW. 10-Year Follow-up of Intensive Glucose Control in Type 2 Diabetes. N Engl J Med. 2008 Oct 9;359(15):1577-89.

23. Kooy A, de Jager J, Lehert P, Bets DDD, Wulffelé MG, Donker AJMM, et al. Long-term effects of metformin on metabolism and microvascular and macrovascular disease in patients with type 2 diabetes mellitus. Arch Intern Med. 2009 Mar 23;169(6):616-25.

24. Mary A, Hartemann A, Liabeuf S, Aubert CE, Kemel S, Salem JE, et al. Association between metformin use and below-the-knee arterial calcification score in type 2 diabetic patients. Cardiovasc Diabetol. 2017 Dec 15;16(1):24.

25. Foretz M, Guigas B, Bertrand L, Pollak M, Viollet B. Metformin: from mechanisms of action to therapies. Cell Metab. 2014 Dec 2;20(6):953-66.

26. de Jager J, Kooy A, Schalkwijk C, van der Kolk J, Lehert P, Bets D, et al. Long-term effects of metformin on endothelial function in type 2 diabetes: a randomized controlled trial. J Intern Med. 2014 Jan;275(1):59-70.
compared with conventional treatment and risk of complications in patients with type 2 diabetes (UKPDS 33). Lancet. 1998 Sep 12;352(9131):837-53.

20. Margolis KL, O'Connor PJ, Morgan TM, Buse JB, Cohen RM, Cushman WC, et al. Outcomes of combined cardiovascular risk factor management strategies in type 2 diabetes: the ACCORD randomized trial. Diabetes Care. 2014 Jun;37(6):1721-8.

21. Stratton IM, Adler AI, Neil HAW, Matthews DR, Manley SE, Cull CA, et al. Association of glycaemia with macrovascular and microvascular complications of type 2 diabetes (UKPDS 35): Prospective observational study. Br Med J. 2000 Aug 12;321(7258):405-12.

22. Holman RR, Paul SK, Bethel MA, Matthews DR, Neil HAW. 10-Year Follow-up of Intensive Glucose Control in Type 2 Diabetes. N Engl J Med. 2008 Oct 9;359(15):1577-89.

23. Kooy A, de Jager J, Lehert P, Bets DDD, Wulffelé MG, Donker AJMM, et al. Long-term effects of metformin on metabolism and microvascular and macrovascular disease in patients with type 2 diabetes mellitus. Arch Intern Med. 2009 Mar 23;169(6):616-25.

24. Mary A, Hartemann A, Liabeuf S, Aubert CE, Kemel S, Salem JE, et al. Association between metformin use and below-the-knee arterial calcification score in type 2 diabetic patients. Cardiovasc Diabetol. 2017 Dec 15;16(1):24.

25. Foretz M, Guigas B, Bertrand L, Pollak M, Viollet B. Metformin: from mechanisms of action to therapies. Cell Metab. 2014 Dec 2;20(6):953-66.

26. de Jager J, Kooy A, Schalkwijk C, van der Kolk J, Lehert P, Bets D, et al. Long-term effects of metformin on endothelial function in type 2 diabetes: a randomized controlled trial. J Intern Med. 2014 Jan;275(1):59-70.
395 **VI. Funding**

396 No funding.

397 **VII. Conflict of interest**

398 No conflict of interest

399 **VIII. Author contributions**

400 ST, AG, GM, and EM conceived and supervised the study. ST, NM, LG, GD, and GG
401 collected the data. YT and HM performed the statistical analysis. AA and TM ran the
402 statistical analysis. ST and GG wrote the manuscript. All authors interpreted the data,
403 drafted and revised the manuscript, and approved the final version.
395 **VI. Funding**

396 No funding.

397 **VII. Conflict of interest**

398 No conflict of interest

399 **VIII. Author contributions**

400 ST, AG, GM, and EM conceived and supervised the study. ST, NM, LG, GD, and GG
401 collected the data. YT and HM performed the statistical analysis. AA and TM ran the
402 statistical analysis. ST and GG wrote the manuscript. All authors interpreted the data,
403 drafted and revised the manuscript, and approved the final version.
# IX. Tables and figures

## I. Table 1. Patient characteristics

BMI: Body mass index. CKD: Chronic Kidney Disease. LDL: Low-density lipoprotein. PAD:

Peripheral arterial disease. A diabetic wound refers to a foot wound secondary to diabetic neuropathy.

<table><thead><tr><th></th><th>Patients (n=100)</th></tr></thead><tbody><tr><td><strong>Patients</strong></td><td></td></tr><tr><td>Age (years)</td><td>70.9 ±9.2</td></tr><tr><td>Male gender</td><td>86</td></tr><tr><td>Overweight and obesity</td><td>61</td></tr><tr><td>Obesity</td><td>24</td></tr><tr><td>BMI (kg/m2)</td><td>27.0 ±5.1</td></tr><tr><td>Active smoking</td><td>12</td></tr><tr><td>Systolic blood pressure (mmHg)</td><td>138.1 ±18.1</td></tr><tr><td>Diastolic blood pressure (mmHg)</td><td>72.2 ± 14.7</td></tr><tr><td>LDLc (mmol/L)</td><td>1.8 ±0.9</td></tr><tr><td>Triglycerides (mmol/L)</td><td>1.9 ±1.0</td></tr><tr><td>HBA1c (%)</td><td>7.3 ±1.7</td></tr><tr><td><strong>Medical history</strong></td><td></td></tr><tr><td>Hypertension</td><td>100</td></tr><tr><td>Dyslipidaemia</td><td>98</td></tr><tr><td>Abdominal aortic aneurysm</td><td>6</td></tr><tr><td>Stroke</td><td>16</td></tr><tr><td>Carotid artery disease</td><td>67</td></tr><tr><td>Coronary artery disease</td><td>55</td></tr><tr><td>Coronary revascularisation</td><td>47</td></tr><tr><td>Heart failure</td><td>19</td></tr><tr><td>Atrial fibrillation</td><td>22</td></tr><tr><td><strong>Diabetes mellitus history and complications</strong></td><td></td></tr><tr><td>Duration of diabetes (year)</td><td>17.4 ± 10.4</td></tr><tr><td>Diabetic wound (number)</td><td>64</td></tr><tr><td>Diabetic neuropathy</td><td>79</td></tr><tr><td>Diabetic retinopathy</td><td>41</td></tr><tr><td>Proliferating diabetic retinopathy</td><td>19</td></tr><tr><td>Diabetic nephropathy</td><td>89</td></tr><tr><td>Microalbuminuria (30-300mg/24h)</td><td>38</td></tr><tr><td>Proteinuria (≥300mg/24h)</td><td>31</td></tr><tr><td>CKD (DFG&lt;60ml/min)</td><td>53</td></tr><tr><td>CKD stage 3 (GFR: 30-59 ml/min)</td><td>32</td></tr><tr><td>CKD stage 4 (GFR: 15-29 ml/min)</td><td>6</td></tr><tr><td>CKD stage 5 (GFR&lt;15 ml/min)</td><td>15</td></tr><tr><td>Dialysis</td><td>14</td></tr></tbody></table>
# IX. Tables and figures

## I. Table 1. Patient characteristics

BMI: Body mass index. CKD: Chronic Kidney Disease. LDL: Low-density lipoprotein. PAD:

Peripheral arterial disease. A diabetic wound refers to a foot wound secondary to diabetic neuropathy.

<table><thead><tr><th></th><th>Patients (n=100)</th></tr></thead><tbody><tr><td><strong>Patients</strong></td><td></td></tr><tr><td>Age (years)</td><td>70.9 ±9.2</td></tr><tr><td>Male gender</td><td>86</td></tr><tr><td>Overweight and obesity</td><td>61</td></tr><tr><td>Obesity</td><td>24</td></tr><tr><td>BMI (kg/m2)</td><td>27.0 ±5.1</td></tr><tr><td>Active smoking</td><td>12</td></tr><tr><td>Systolic blood pressure (mmHg)</td><td>138.1 ±18.1</td></tr><tr><td>Diastolic blood pressure (mmHg)</td><td>72.2 ± 14.7</td></tr><tr><td>LDLc (mmol/L)</td><td>1.8 ±0.9</td></tr><tr><td>Triglycerides (mmol/L)</td><td>1.9 ±1.0</td></tr><tr><td>HBA1c (%)</td><td>7.3 ±1.7</td></tr><tr><td><strong>Medical history</strong></td><td></td></tr><tr><td>Hypertension</td><td>100</td></tr><tr><td>Dyslipidaemia</td><td>98</td></tr><tr><td>Abdominal aortic aneurysm</td><td>6</td></tr><tr><td>Stroke</td><td>16</td></tr><tr><td>Carotid artery disease</td><td>67</td></tr><tr><td>Coronary artery disease</td><td>55</td></tr><tr><td>Coronary revascularisation</td><td>47</td></tr><tr><td>Heart failure</td><td>19</td></tr><tr><td>Atrial fibrillation</td><td>22</td></tr><tr><td><strong>Diabetes mellitus history and complications</strong></td><td></td></tr><tr><td>Duration of diabetes (year)</td><td>17.4 ± 10.4</td></tr><tr><td>Diabetic wound (number)</td><td>64</td></tr><tr><td>Diabetic neuropathy</td><td>79</td></tr><tr><td>Diabetic retinopathy</td><td>41</td></tr><tr><td>Proliferating diabetic retinopathy</td><td>19</td></tr><tr><td>Diabetic nephropathy</td><td>89</td></tr><tr><td>Microalbuminuria (30-300mg/24h)</td><td>38</td></tr><tr><td>Proteinuria (≥300mg/24h)</td><td>31</td></tr><tr><td>CKD (DFG&lt;60ml/min)</td><td>53</td></tr><tr><td>CKD stage 3 (GFR: 30-59 ml/min)</td><td>32</td></tr><tr><td>CKD stage 4 (GFR: 15-29 ml/min)</td><td>6</td></tr><tr><td>CKD stage 5 (GFR&lt;15 ml/min)</td><td>15</td></tr><tr><td>Dialysis</td><td>14</td></tr></tbody></table>
<table><thead><tr><th>PAD profile</th><th></th></tr></thead><tbody><tr><td>Stage 1=asymptomatic</td><td>19</td></tr><tr><td>Stage 2=claudication</td><td>27</td></tr><tr><td>Stage 3=resting pain</td><td>2</td></tr><tr><td>Stage 4=arterial trophic disorder</td><td>52</td></tr></tbody></table>

409

410

## II. Table 2. Monitoring of cardiovascular events and deaths from all causes

411

MACE: Major Adverse Cardiovascular Events. MALE: Major Adverse Limb Events.

412

<table><thead><tr><th></th><th>At M6<br>N=100</th><th>At M12<br>N=100</th></tr></thead><tbody><tr><td>Patients with new leg ulcers</td><td>29</td><td>39</td></tr><tr><td>Patients with at least one<br>Local infection</td><td>30</td><td>38</td></tr><tr><td>At least one hospitalization</td><td>54</td><td>73</td></tr><tr><td>Patients with MALE</td><td>32</td><td>37</td></tr><tr><td>Lower limb revascularization</td><td>31</td><td>36</td></tr><tr><td>Any lower limb amputation</td><td>13</td><td>16</td></tr><tr><td>Major lower limb amputation</td><td>2</td><td>4</td></tr><tr><td>Minor lower limb amputation</td><td>11</td><td>12</td></tr><tr><td>Patients with MACE</td><td>10</td><td>13</td></tr><tr><td>Myocardial infarction</td><td>5</td><td>6</td></tr><tr><td>Ischemic stroke</td><td>1</td><td>1</td></tr><tr><td>Cardiovascular deaths</td><td>8</td><td>10</td></tr><tr><td>All-cause deaths</td><td>11</td><td>14</td></tr></tbody></table>

413

414
<table><thead><tr><th>PAD profile</th><th></th></tr></thead><tbody><tr><td>Stage 1=asymptomatic</td><td>19</td></tr><tr><td>Stage 2=claudication</td><td>27</td></tr><tr><td>Stage 3=resting pain</td><td>2</td></tr><tr><td>Stage 4=arterial trophic disorder</td><td>52</td></tr></tbody></table>

409

410

## II. Table 2. Monitoring of cardiovascular events and deaths from all causes

411

MACE: Major Adverse Cardiovascular Events. MALE: Major Adverse Limb Events.

412

<table><thead><tr><th></th><th>At M6<br>N=100</th><th>At M12<br>N=100</th></tr></thead><tbody><tr><td>Patients with new leg ulcers</td><td>29</td><td>39</td></tr><tr><td>Patients with at least one<br>Local infection</td><td>30</td><td>38</td></tr><tr><td>At least one hospitalization</td><td>54</td><td>73</td></tr><tr><td>Patients with MALE</td><td>32</td><td>37</td></tr><tr><td>Lower limb revascularization</td><td>31</td><td>36</td></tr><tr><td>Any lower limb amputation</td><td>13</td><td>16</td></tr><tr><td>Major lower limb amputation</td><td>2</td><td>4</td></tr><tr><td>Minor lower limb amputation</td><td>11</td><td>12</td></tr><tr><td>Patients with MACE</td><td>10</td><td>13</td></tr><tr><td>Myocardial infarction</td><td>5</td><td>6</td></tr><tr><td>Ischemic stroke</td><td>1</td><td>1</td></tr><tr><td>Cardiovascular deaths</td><td>8</td><td>10</td></tr><tr><td>All-cause deaths</td><td>11</td><td>14</td></tr></tbody></table>

413

414
415 **III. Table 3. Events at complete follow-up (12 months) in patients with Major Adverse Limb Events (MALE) vs. without MALE.**

417 MACE: Major Adverse Cardiovascular Events.

418

<table><thead><tr><th>Covariate</th><th>Whole sample<br>(N=100)</th><th>Patients with<br>MALE (N=37)</th><th>Patients without<br>MALE (N=63)</th><th>P-value</th></tr></thead><tbody><tr><td>Major amputation</td><td>4</td><td>4 (10.8%)</td><td>0 (0%)</td><td>0.017</td></tr><tr><td>Minor amputation</td><td>12</td><td>11 (29.7%)</td><td>1 (1.6%)</td><td>0.001</td></tr><tr><td>All-cause Death</td><td>14</td><td>5 (13.5%)</td><td>9 (14.3%)</td><td>0.914</td></tr><tr><td>Cardiovascular death</td><td>10</td><td>5 (13.5%)</td><td>5 (7.9%)</td><td>0.369</td></tr><tr><td>Non cardiovascular death</td><td>4</td><td>0 (0%)</td><td>4 (6.5%)</td><td>0.294</td></tr><tr><td>Lower limb arterial<br>Revascularization</td><td>36</td><td>36 (97.3%)</td><td>0 (0%)</td><td>0.001</td></tr><tr><td>MACE</td><td>13</td><td>6 (16.2%)</td><td>7 (11.1%)</td><td>0.464</td></tr><tr><td>Leg ulcer</td><td>39</td><td>22 (59.5%)</td><td>17 (27.0%)</td><td>0.001</td></tr><tr><td>Local infection</td><td>38</td><td>21 (56.8%)</td><td>17 (27.0%)</td><td>0.003</td></tr><tr><td>Ischemic stroke</td><td>1</td><td>0 (0%)</td><td>1 (1.6%)</td><td>1.000</td></tr><tr><td>Myocardial infarction</td><td>6</td><td>4 (10.8%)</td><td>2 (3.2%)</td><td>0.190</td></tr></tbody></table>

419

420
415 **III. Table 3. Events at complete follow-up (12 months) in patients with Major Adverse Limb Events (MALE) vs. without MALE.**

417 MACE: Major Adverse Cardiovascular Events.

418

<table><thead><tr><th>Covariate</th><th>Whole sample<br>(N=100)</th><th>Patients with<br>MALE (N=37)</th><th>Patients without<br>MALE (N=63)</th><th>P-value</th></tr></thead><tbody><tr><td>Major amputation</td><td>4</td><td>4 (10.8%)</td><td>0 (0%)</td><td>0.017</td></tr><tr><td>Minor amputation</td><td>12</td><td>11 (29.7%)</td><td>1 (1.6%)</td><td>0.001</td></tr><tr><td>All-cause Death</td><td>14</td><td>5 (13.5%)</td><td>9 (14.3%)</td><td>0.914</td></tr><tr><td>Cardiovascular death</td><td>10</td><td>5 (13.5%)</td><td>5 (7.9%)</td><td>0.369</td></tr><tr><td>Non cardiovascular death</td><td>4</td><td>0 (0%)</td><td>4 (6.5%)</td><td>0.294</td></tr><tr><td>Lower limb arterial<br>Revascularization</td><td>36</td><td>36 (97.3%)</td><td>0 (0%)</td><td>0.001</td></tr><tr><td>MACE</td><td>13</td><td>6 (16.2%)</td><td>7 (11.1%)</td><td>0.464</td></tr><tr><td>Leg ulcer</td><td>39</td><td>22 (59.5%)</td><td>17 (27.0%)</td><td>0.001</td></tr><tr><td>Local infection</td><td>38</td><td>21 (56.8%)</td><td>17 (27.0%)</td><td>0.003</td></tr><tr><td>Ischemic stroke</td><td>1</td><td>0 (0%)</td><td>1 (1.6%)</td><td>1.000</td></tr><tr><td>Myocardial infarction</td><td>6</td><td>4 (10.8%)</td><td>2 (3.2%)</td><td>0.190</td></tr></tbody></table>

419

420
421 **IV. Table 4. Events at complete follow-up in patients with Major Adverse Cardiovascular Events (MACE) vs. without MACE.**

423

<table><thead><tr><th>Covariate</th><th>Whole sample<br>(N=100)</th><th>Patients with<br>MACE (N=13)</th><th>Patients without<br>MACE (N=87)</th><th>P-value</th></tr></thead><tbody><tr><td>Major amputation</td><td>4</td><td>0 (0%)</td><td>4 (4.6%)</td><td>1</td></tr><tr><td>Minor amputation</td><td>12</td><td><strong>4 (30.8%)</strong></td><td><strong>8 (9.2%)</strong></td><td><strong>0.048</strong></td></tr><tr><td>All-cause Death</td><td>14</td><td><strong>10 (76.9%)</strong></td><td><strong>4 (4.6%)</strong></td><td><strong>0.001</strong></td></tr><tr><td>Cardiovascular death</td><td>10</td><td><strong>10 (76.9%)</strong></td><td><strong>0 (0%)</strong></td><td><strong>0.001</strong></td></tr><tr><td>Non cardiovascular<br>death</td><td>4</td><td>0 (0%)</td><td>4 (4.6%)</td><td>1</td></tr><tr><td>Lower limb arterial<br>Revascularization</td><td>36</td><td>6 (46.1%)</td><td>30 (34.5%)</td><td>0.414</td></tr><tr><td>Leg ulcer</td><td>39</td><td>8 (61.5%)</td><td>31 (35.6%)</td><td>0.074</td></tr><tr><td>Local infection</td><td>38</td><td>7 (53.8%)</td><td>31 (35.6%)</td><td>0.207</td></tr><tr><td>Ischemic stroke</td><td>1</td><td>1 (7.7%)</td><td>0 (0%)</td><td>0.13</td></tr><tr><td>Myocardial infarction</td><td>6</td><td><strong>6 (46.1%)</strong></td><td><strong>0 (0%)</strong></td><td><strong>0.001</strong></td></tr></tbody></table>

424

425
421 **IV. Table 4. Events at complete follow-up in patients with Major Adverse Cardiovascular Events (MACE) vs. without MACE.**

423

<table><thead><tr><th>Covariate</th><th>Whole sample<br>(N=100)</th><th>Patients with<br>MACE (N=13)</th><th>Patients without<br>MACE (N=87)</th><th>P-value</th></tr></thead><tbody><tr><td>Major amputation</td><td>4</td><td>0 (0%)</td><td>4 (4.6%)</td><td>1</td></tr><tr><td>Minor amputation</td><td>12</td><td><strong>4 (30.8%)</strong></td><td><strong>8 (9.2%)</strong></td><td><strong>0.048</strong></td></tr><tr><td>All-cause Death</td><td>14</td><td><strong>10 (76.9%)</strong></td><td><strong>4 (4.6%)</strong></td><td><strong>0.001</strong></td></tr><tr><td>Cardiovascular death</td><td>10</td><td><strong>10 (76.9%)</strong></td><td><strong>0 (0%)</strong></td><td><strong>0.001</strong></td></tr><tr><td>Non cardiovascular<br>death</td><td>4</td><td>0 (0%)</td><td>4 (4.6%)</td><td>1</td></tr><tr><td>Lower limb arterial<br>Revascularization</td><td>36</td><td>6 (46.1%)</td><td>30 (34.5%)</td><td>0.414</td></tr><tr><td>Leg ulcer</td><td>39</td><td>8 (61.5%)</td><td>31 (35.6%)</td><td>0.074</td></tr><tr><td>Local infection</td><td>38</td><td>7 (53.8%)</td><td>31 (35.6%)</td><td>0.207</td></tr><tr><td>Ischemic stroke</td><td>1</td><td>1 (7.7%)</td><td>0 (0%)</td><td>0.13</td></tr><tr><td>Myocardial infarction</td><td>6</td><td><strong>6 (46.1%)</strong></td><td><strong>0 (0%)</strong></td><td><strong>0.001</strong></td></tr></tbody></table>

424

425
426 **V. Figure 1.**

427 Forest plot of independent factors associated with Major Adverse Limb Events (95% CI).

428 PAD: peripheral arterial disease.

<table><thead><tr><th>Variable</th><th>N</th><th>Odds ratio</th><th>P</th></tr></thead><tbody><tr><td>PAD</td><td>STAGE 2 27</td><td></td><td>0.72 (0.14, 3.69) 0.691</td></tr><tr><td></td><td>STAGE 3 2</td><td></td><td>7.74 (0.25, 240.62) 0.189</td></tr><tr><td></td><td>STAGE 4 52</td><td></td><td>3.24 (0.94, 13.27) 0.076</td></tr><tr><td>Iloprost</td><td>Yes 12</td><td></td><td>5.70 (1.31, 31.93) 0.029</td></tr><tr><td>Metformin</td><td>Yes 56</td><td></td><td>0.26 (0.10, 0.68) 0.007</td></tr></tbody></table>

429

430

431
426 **V. Figure 1.**

427 Forest plot of independent factors associated with Major Adverse Limb Events (95% CI).

428 PAD: peripheral arterial disease.

<table><thead><tr><th>Variable</th><th>N</th><th>Odds ratio</th><th>P</th></tr></thead><tbody><tr><td>PAD</td><td>STAGE 2 27</td><td></td><td>0.72 (0.14, 3.69) 0.691</td></tr><tr><td></td><td>STAGE 3 2</td><td></td><td>7.74 (0.25, 240.62) 0.189</td></tr><tr><td></td><td>STAGE 4 52</td><td></td><td>3.24 (0.94, 13.27) 0.076</td></tr><tr><td>Iloprost</td><td>Yes 12</td><td></td><td>5.70 (1.31, 31.93) 0.029</td></tr><tr><td>Metformin</td><td>Yes 56</td><td></td><td>0.26 (0.10, 0.68) 0.007</td></tr></tbody></table>

429

430

431
<figure><img src="image_1.png" /><figcaption>432 **VI. Figure 2.**</figcaption></figure>

433 Forest plot of independent factors associated with all-cause death in multivariate

434 analysis

435

436
<figure><img src="image_2.png" /><figcaption>432 **VI. Figure 2.**</figcaption></figure>

433 Forest plot of independent factors associated with all-cause death in multivariate

434 analysis

435

436
# X. Supplementary material

## I. Supplementary data 1. Drug treatment of patients

<table><thead><tr><td>Medication</td><td>Patients (n=100)</td></tr></thead><tbody><tr><td>ACE inhibitors or ARB2</td><td>91</td></tr><tr><td>Statin</td><td>95</td></tr><tr><td>Anti-platelet therapy</td><td>90</td></tr><tr><td>Anticoagulant</td><td>18</td></tr><tr><td>Anti-platelet therapy or anticoagulant</td><td>98</td></tr><tr><td>Anti-platelet therapy and anticoagulant</td><td>10</td></tr><tr><td>Oral antidiabetic drug</td><td>66</td></tr><tr><td>GLP-1 analogue</td><td>7</td></tr><tr><td>Gliptin</td><td>19</td></tr><tr><td>Sulfamide</td><td>18</td></tr><tr><td>Glinide</td><td>8</td></tr><tr><td>Metformin</td><td>56</td></tr><tr><td>SGLT-2 inhibitors</td><td>0</td></tr><tr><td>Alpha Glucosidase Inhibitor</td><td>1</td></tr><tr><td>Insulin</td><td>58</td></tr><tr><td>Antibiotic</td><td>14</td></tr></tbody></table>

ACE: angiotensin conversion enzyme. GLP-1: glucagon-like peptide 1. SGLT-2: Sodium/glucose cotransporter 2.
# X. Supplementary material

## I. Supplementary data 1. Drug treatment of patients

<table><thead><tr><td>Medication</td><td>Patients (n=100)</td></tr></thead><tbody><tr><td>ACE inhibitors or ARB2</td><td>91</td></tr><tr><td>Statin</td><td>95</td></tr><tr><td>Anti-platelet therapy</td><td>90</td></tr><tr><td>Anticoagulant</td><td>18</td></tr><tr><td>Anti-platelet therapy or anticoagulant</td><td>98</td></tr><tr><td>Anti-platelet therapy and anticoagulant</td><td>10</td></tr><tr><td>Oral antidiabetic drug</td><td>66</td></tr><tr><td>GLP-1 analogue</td><td>7</td></tr><tr><td>Gliptin</td><td>19</td></tr><tr><td>Sulfamide</td><td>18</td></tr><tr><td>Glinide</td><td>8</td></tr><tr><td>Metformin</td><td>56</td></tr><tr><td>SGLT-2 inhibitors</td><td>0</td></tr><tr><td>Alpha Glucosidase Inhibitor</td><td>1</td></tr><tr><td>Insulin</td><td>58</td></tr><tr><td>Antibiotic</td><td>14</td></tr></tbody></table>

ACE: angiotensin conversion enzyme. GLP-1: glucagon-like peptide 1. SGLT-2: Sodium/glucose cotransporter 2.
443 **II. Supplementary data 2. Forest plot of independent factors associated with**

444 **MACE at one year**

<table><thead><tr><th>Variable</th><th>N</th><th>Odds ratio</th><th>p</th></tr></thead><tbody><tr><td>Wound at inclusion</td><td>61</td><td>4.26 (0.66, 83.92)</td><td>0.196</td></tr><tr><td>Physical activity</td><td>46</td><td>0.07 (0.00, 0.44)</td><td>0.021</td></tr></tbody></table>

445

446
443 **II. Supplementary data 2. Forest plot of independent factors associated with**

444 **MACE at one year**

<table><thead><tr><th>Variable</th><th>N</th><th>Odds ratio</th><th>p</th></tr></thead><tbody><tr><td>Wound at inclusion</td><td>61</td><td>4.26 (0.66, 83.92)</td><td>0.196</td></tr><tr><td>Physical activity</td><td>46</td><td>0.07 (0.00, 0.44)</td><td>0.021</td></tr></tbody></table>

445

446
447 **III. Supplementary data 3. Events at complete follow-up in patients with death**
448 **during follow-up vs. patients still alive.**

449

<table><thead><tr><th>Covariate</th><th>Whole sample<br>(N=100)</th><th>Deceased patients<br>(N=14)</th><th>Still alive patients<br>(N=86)</th><th>P-value</th></tr></thead><tbody><tr><td>Major amputation</td><td>4</td><td>0 (0%)</td><td>4 (4.6%)</td><td>1</td></tr><tr><td>Minor amputation</td><td>12</td><td>3 (21.4%)</td><td>9 (10.5%)</td><td>0.367</td></tr><tr><td>All-cause Death</td><td>14</td><td><strong>14 (100%)</strong></td><td><strong>0 (0.0%)</strong></td><td><strong>0.001</strong></td></tr><tr><td>Cardiovascular death</td><td>10</td><td><strong>10 (71.4%)</strong></td><td><strong>0 (0.0%)</strong></td><td><strong>0.001</strong></td></tr><tr><td>Non cardiovascular death</td><td>4</td><td><strong>4 (28.6%)</strong></td><td><strong>0 (0.0%)</strong></td><td><strong>0.001</strong></td></tr><tr><td>MACE</td><td>13</td><td><strong>10 (71.4%)</strong></td><td><strong>3 (3.5%)</strong></td><td><strong>0.001</strong></td></tr><tr><td>Lower limb arterial Revascularization</td><td>36</td><td>5 (35.7%)</td><td>31 (36%)</td><td>0.981</td></tr><tr><td>Leg ulcer</td><td>39</td><td>8 (57.1%)</td><td>31 (36%)</td><td>0.133</td></tr><tr><td>Local infection</td><td>38</td><td>7 (50%)</td><td>31 (36%)</td><td>0.319</td></tr><tr><td>Ischemic stroke</td><td>1</td><td>1 (7.1%)</td><td>0 (0%)</td><td>0.14</td></tr><tr><td>Myocardial infarction</td><td>6</td><td><strong>3 (21.4%)</strong></td><td><strong>3 (3.5%)</strong></td><td><strong>0.034</strong></td></tr></tbody></table>

450

451
447 **III. Supplementary data 3. Events at complete follow-up in patients with death**
448 **during follow-up vs. patients still alive.**

449

<table><thead><tr><th>Covariate</th><th>Whole sample<br>(N=100)</th><th>Deceased patients<br>(N=14)</th><th>Still alive patients<br>(N=86)</th><th>P-value</th></tr></thead><tbody><tr><td>Major amputation</td><td>4</td><td>0 (0%)</td><td>4 (4.6%)</td><td>1</td></tr><tr><td>Minor amputation</td><td>12</td><td>3 (21.4%)</td><td>9 (10.5%)</td><td>0.367</td></tr><tr><td>All-cause Death</td><td>14</td><td><strong>14 (100%)</strong></td><td><strong>0 (0.0%)</strong></td><td><strong>0.001</strong></td></tr><tr><td>Cardiovascular death</td><td>10</td><td><strong>10 (71.4%)</strong></td><td><strong>0 (0.0%)</strong></td><td><strong>0.001</strong></td></tr><tr><td>Non cardiovascular death</td><td>4</td><td><strong>4 (28.6%)</strong></td><td><strong>0 (0.0%)</strong></td><td><strong>0.001</strong></td></tr><tr><td>MACE</td><td>13</td><td><strong>10 (71.4%)</strong></td><td><strong>3 (3.5%)</strong></td><td><strong>0.001</strong></td></tr><tr><td>Lower limb arterial Revascularization</td><td>36</td><td>5 (35.7%)</td><td>31 (36%)</td><td>0.981</td></tr><tr><td>Leg ulcer</td><td>39</td><td>8 (57.1%)</td><td>31 (36%)</td><td>0.133</td></tr><tr><td>Local infection</td><td>38</td><td>7 (50%)</td><td>31 (36%)</td><td>0.319</td></tr><tr><td>Ischemic stroke</td><td>1</td><td>1 (7.1%)</td><td>0 (0%)</td><td>0.14</td></tr><tr><td>Myocardial infarction</td><td>6</td><td><strong>3 (21.4%)</strong></td><td><strong>3 (3.5%)</strong></td><td><strong>0.034</strong></td></tr></tbody></table>

450

451
<table><thead><tr><th>Covariate</th><th>Patients without metformin (n=44)</th><th>Patients with metformin (n=56)</th><th>P-value</th></tr></thead><tbody><tr><td>Age (years)</td><td>74.2 (9.57)</td><td>68.3 (8.14)</td><td>0.001</td></tr><tr><td>Male gender</td><td>37 (84.1%)</td><td>49 (87.5%)</td><td>0.626</td></tr><tr><td>CKD (DFG&lt;60ml/min)</td><td>34 (79.1%)</td><td>19 (33.9%)</td><td>&lt;0.001</td></tr><tr><td>CKD stage 3 (GFR: 30-59 ml/min)</td><td>14 (34.1%)</td><td>18 (34%)</td><td>0.985</td></tr><tr><td>CKD stage 4 (GFR: 15-29 ml/min)</td><td>6 (14.6%)</td><td>0 (0%)</td><td>&lt;0.006</td></tr><tr><td>CKD stage 5 (GFR&lt;15 ml/min)</td><td>15 (36.6%)</td><td>0 (0%)</td><td>&lt;0.001</td></tr><tr><td>Statin</td><td>40 (90.9%)</td><td>55 (99.2%)</td><td>0.166</td></tr><tr><td>Anti-platelet therapy</td><td>40 (90.9%)</td><td>50 (89.3%)</td><td>1</td></tr><tr><td>GLP-1 analogue</td><td>0 (0%)</td><td>7 (12.5%)</td><td>0.017</td></tr><tr><td>Gliptin</td><td>4 (9.1%)</td><td>15 (26.8%)</td><td>0.038</td></tr><tr><td>Sulfamide</td><td>2 (4.6%)</td><td>16 (28.6%)</td><td>0.002</td></tr><tr><td>Glinide</td><td>5 (11.4%)</td><td>3 (5.4%)</td><td>0.295</td></tr><tr><td>SGLT-2 inhibitors</td><td>0 (0%)</td><td>0 (0%)</td><td>1</td></tr><tr><td>Alpha Glucosidase Inhibitor</td><td>0 (0%)</td><td>1 (1.8%)</td><td>1</td></tr><tr><td>Insulin</td><td>34 (77.3%)</td><td>24 (42.9%)</td><td>0.001</td></tr><tr><td>Major amputation</td><td>2 (4.5%)</td><td>2 (3.6%)</td><td>1</td></tr><tr><td>Minor amputation</td><td>7 (15.9%)</td><td>5 (8.9%)</td><td>0.286</td></tr><tr><td>All-cause Death</td><td>9 (20.4%)</td><td>5 (8.9%)</td><td>0.099</td></tr><tr><td>Cardiovascular death</td><td>6 (13.6%)</td><td>4 (7.1%)</td><td>0.328</td></tr><tr><td>Non cardiovascular</td><td>3 (6.8%)</td><td>1 (1.8%)</td><td>0.317</td></tr></tbody></table>
<table><thead><tr><th>Covariate</th><th>Patients without metformin (n=44)</th><th>Patients with metformin (n=56)</th><th>P-value</th></tr></thead><tbody><tr><td>Age (years)</td><td>74.2 (9.57)</td><td>68.3 (8.14)</td><td>0.001</td></tr><tr><td>Male gender</td><td>37 (84.1%)</td><td>49 (87.5%)</td><td>0.626</td></tr><tr><td>CKD (DFG&lt;60ml/min)</td><td>34 (79.1%)</td><td>19 (33.9%)</td><td>&lt;0.001</td></tr><tr><td>CKD stage 3 (GFR: 30-59 ml/min)</td><td>14 (34.1%)</td><td>18 (34%)</td><td>0.985</td></tr><tr><td>CKD stage 4 (GFR: 15-29 ml/min)</td><td>6 (14.6%)</td><td>0 (0%)</td><td>&lt;0.006</td></tr><tr><td>CKD stage 5 (GFR&lt;15 ml/min)</td><td>15 (36.6%)</td><td>0 (0%)</td><td>&lt;0.001</td></tr><tr><td>Statin</td><td>40 (90.9%)</td><td>55 (99.2%)</td><td>0.166</td></tr><tr><td>Anti-platelet therapy</td><td>40 (90.9%)</td><td>50 (89.3%)</td><td>1</td></tr><tr><td>GLP-1 analogue</td><td>0 (0%)</td><td>7 (12.5%)</td><td>0.017</td></tr><tr><td>Gliptin</td><td>4 (9.1%)</td><td>15 (26.8%)</td><td>0.038</td></tr><tr><td>Sulfamide</td><td>2 (4.6%)</td><td>16 (28.6%)</td><td>0.002</td></tr><tr><td>Glinide</td><td>5 (11.4%)</td><td>3 (5.4%)</td><td>0.295</td></tr><tr><td>SGLT-2 inhibitors</td><td>0 (0%)</td><td>0 (0%)</td><td>1</td></tr><tr><td>Alpha Glucosidase Inhibitor</td><td>0 (0%)</td><td>1 (1.8%)</td><td>1</td></tr><tr><td>Insulin</td><td>34 (77.3%)</td><td>24 (42.9%)</td><td>0.001</td></tr><tr><td>Major amputation</td><td>2 (4.5%)</td><td>2 (3.6%)</td><td>1</td></tr><tr><td>Minor amputation</td><td>7 (15.9%)</td><td>5 (8.9%)</td><td>0.286</td></tr><tr><td>All-cause Death</td><td>9 (20.4%)</td><td>5 (8.9%)</td><td>0.099</td></tr><tr><td>Cardiovascular death</td><td>6 (13.6%)</td><td>4 (7.1%)</td><td>0.328</td></tr><tr><td>Non cardiovascular</td><td>3 (6.8%)</td><td>1 (1.8%)</td><td>0.317</td></tr></tbody></table>
<table><tr><td>death</td><td></td><td></td><td></td></tr><tr><td>Lower limb arterial</td><td>23 (52.3%)</td><td>13 (23.2%)</td><td>0.003</td></tr><tr><td>Revascularization</td><td></td><td></td><td></td></tr><tr><td>MACE</td><td>8 (18.2%)</td><td>5 (8.9%)</td><td>0.172</td></tr><tr><td>Leg ulcer</td><td>22 (50.0%)</td><td>17 (30.4%)</td><td>0.046</td></tr><tr><td>Local infection</td><td>22 (50.0%)</td><td>16 (28.6%)</td><td>0.028</td></tr><tr><td>Ischemic stroke</td><td>1 (2.3%)</td><td>0 (0%)</td><td>0.440</td></tr><tr><td>Myocardial infarction</td><td>5 (11.4%)</td><td>1 (1.8%)</td><td>0.084</td></tr></table>
<table><tr><td>death</td><td></td><td></td><td></td></tr><tr><td>Lower limb arterial</td><td>23 (52.3%)</td><td>13 (23.2%)</td><td>0.003</td></tr><tr><td>Revascularization</td><td></td><td></td><td></td></tr><tr><td>MACE</td><td>8 (18.2%)</td><td>5 (8.9%)</td><td>0.172</td></tr><tr><td>Leg ulcer</td><td>22 (50.0%)</td><td>17 (30.4%)</td><td>0.046</td></tr><tr><td>Local infection</td><td>22 (50.0%)</td><td>16 (28.6%)</td><td>0.028</td></tr><tr><td>Ischemic stroke</td><td>1 (2.3%)</td><td>0 (0%)</td><td>0.440</td></tr><tr><td>Myocardial infarction</td><td>5 (11.4%)</td><td>1 (1.8%)</td><td>0.084</td></tr></table>