#1626 The role of sodium-glucose cotransporter 2 inhibitors in diabetic nephropathy and non diabetic renal disease in diabetes mellitus type 2 patients
Authors: Ibernón Meritxell , Navarro Maru , Goma Montserrat , Tango Ariel , Rap Oana , Cabrera Cristina , Sánchez Ana , Rodriguez Neus , Ruiz Pilar 
Published: May 2024

Abstract

Background and Aims
Diabetes Mellitus type 2 (DM2) leads to chronic kidney disease in a 30-40% of diabetic patients and it is the major cause of end stage renal disease (ESRD). The clinical course of diabetic kidney disease is very heterogeneous and there is a lack of agreement between clinical parameters and renal histology. Besides, lesions of non-diabetic kidney disease (NDRD) can coexist with lesions of diabetic nephropathy (DN) in two-thirds of kidney biopsies in patients with diabetes. There is not a specific treatment against diabetic kidney disease, treatment based in the blockade of renin-angiotensin-aldosterone system has demonstrated a delay of kidney function decline but the diabetic kidney disease is still the main cause of renal replacement by dialysis. Recently, a new class of oral glucose -lowering drugs, sodium-glucose cotransporter 2 (SGLT2) inhibitors, have shown beneficial effects into cardiovascular protection and chronic kidney disease in diabetic patients but it is not clear the beneficial effect in DN. The aim of this study is to evaluate the role of SGLT2 inhibitors in diabetic patients with DN biopsy-confirmed and compare with a group of diabetic patients with NDRD (DN and superimposed non diabetic renal disease lesions, NDRD).

Method
This is a retrospective study with DM2 patients and kidney biopsy performed. Patient demographic characteristics were recorded and diagnosis of Hypertension, duration of DM2, presence or absence of diabetic retinopathy (DR), macrovascular disease and treatment with renin–angiotensin– aldosterone system blockers (RAASB), oral hypoglycaemic agents, insulin, and aldosterone antagonists. Histological lesions were recorded according to the pathologic classification of DN. Renal function was based on estimated filtration rate CKD-EPI (eGFR mil/min/m2), the urine albumin-creatinine ratio (UACR mg/gr) and the 24 h proteinuria (g/24 h). Diabetic patients were classified according to the kidney biopsies in DN and NDRD. The follow up was assessed at the time of sodium-glucose cotransporter 2 (SGLT2) inhibitors started, 6, 12 and 24 months.

Results
A total of 64 DM2 patients with kidney biopsy were included in the study. Basal characteristics are summarized in Table 1. DN was diagnosed in 47% and NDRD in 53% of DM2 patients. DM2 patients with NDRD were older (64 ± 10 vs 70 ± 10, p = 0.017), and with more macrovascular disease than patients with DN, 6 (20%) vs 15 (44%), p = 0.04. Instead, DM2 patients with DN showed higher uACR levels than NDRD (2355 ± 2540 vs 706 ± 730, p = 0.02). A 40% of DM2 patients with DN were classified in nodular sclerosis class III of glomerular classification of DN. Interstitial fibrosis and tubular atrophy score were higher in DN versus NDRD patients, (interstitial fibrosis 12 (40%) vs 3 (9%), p = 0.006, tubular atrophy 10 (33%) vs 3 (9%), p = 0.02, Table 2. At the end of follow up, 20% of DM2 patients developed ESRD. According SGLT2 inhibitors treatment, a higher proportion of ESRD and death were observed in DM2 patients without SGLT2 inhibitors than patients with SGLT2 inhibitors, ESRD 11 (39%) vs 2 (6%), p = 0.001, death 9 (32%) vs 4 (11%), p = 0.03. Serum creatinine levels were lower in DM2 patients with SGLT2 inhibitors (118 ± 63.7 vs 203 ± 80.7, p = 0.001), but no differences was observed in uACR between groups. A significant reduction in serum creatinine levels with better eGFR were observed in both groups (DN and NDRD) under SGLT2 inhibitors comparing to group without SGLT2 inhibitors, serum creatinine levels 124 ± 78 vs 236 ± 83, p = 0.008, 107 ± 40 vs 201 ± 110, p = 0.02, and eGFR mil/min/m2 60.9 ± 27.5 vs 25.1 ± 7.2, p = 0.004, 62.6 ± 21.2 vs 33.7 ± 16.2, p = 0.005, Table 3.

Conclusion
A higher proportion of DM2 showed NDRD lesions in kidney biopsy. Treatment with SGLT2 inhibitors reduced progression of chronic renal disease in DN and NDRD DM2 patients. A reduced progression to ESRD and death were also observed in NDRD DM2 patients with SGLT2 treatment.