MO613: Acute Kidney Injury and Hypoglycaemia Risk in Hospitalized Diabetic Patients
Authors: Castro Pedro , Carreira Ana , Mira Filipe , Oliveira Nuno , Alves Rui 
Published: May 2022

Abstract

BACKGROUND AND AIMS
Acute kidney injury (AKI) remains one of the most common complications in hospitalized diabetic patients. The relationship between chronic kidney disease (CKD) and hypoglycaemia is well established: both renal neoglucogenesis and insulin clearance are diminished in this population, increasing the risk for hypoglycaemic episodes. A correlation between AKI and hypoglycaemia remains to be proven. A recent study stated that AKI increases hypoglycaemia risk in critically ill patients; other showed higher risk for hypoglycaemic episodes after hospital discharge. We focused on a correlation between AKI and hypoglycaemia risk in hospitalized diabetic patients.

METHOD
We performed an observational retrospective analysis of all hospitalized diabetic patients in Internal Medicine's ward between 2018 and 2019. Our sample was divided according to the presence/absence of AKI during hospitalization. We considered AKI as a rise of serum creatinine (SCr) &gt;0.3 mg/dL in 48 h or &gt;50% in a week. Baseline kidney function was calculated using CKD-EPI equation, according to the mean ambulatory SCr from the previous 6 months. All patients with CKD stage ≥4 were excluded. We collected 240 diabetic patients with AKI and, to obtain similar sample sizes, aleatory selected 240 diabetic patients without AKI. Hypoglycaemia was defined as peripheral blood sugar levels &lt;70 mg/dL and stratified according to American Diabetes Association classification. IBM SPSS 23.0 was used to perform all statistical analysis.

RESULTS
We selected 480 diabetic patients with an average age of 81.2 ± 9.2 years; most were women (59.8%) and 36.0% were treated with insulin. Across both populations, hypoglycaemic episodes were more prevalent in insulin-treated patients, with lower baseline glomerular filtration rates (GFR) and higher age and were associated with longer hospitalizations (16.6 ± 12.4 days) and higher 30-day mortality rate {OR 3.7 [confidence interval (CI) 95% 1.6–8.7], P &lt; 0.001}. Diabetic patients with AKI were older (82.7 versus 80.1 years, P = .001), had lower baseline GFR (59.1 versus 70 mL/min/1.73 m2 P &lt; 0.001), longer hospital stays (13.8 ± 11.3 days, P = 0.007) and higher mortality rate (14.0% versus 7.3%, P = 0.05). Hypoglycaemic episodes were more prevalent in diabetic patients with AKI (40.8% versus 15.8%, P &lt; 0.001); the occurrence of AKI during hospitalization increased hypoglycaemia risk by 4.2 times [OR 4.21 (CI 2.56–6.97), P &lt; 0.001]. This relationship maintained after multivariate analysis, which accounted the differences between both groups. The first hypoglycaemic event occurred, on average, 6.7 ± 6.1 days after AKI; a longer time in AKI, irrespective of the severity, associated with higher hypoglycaemia risk and 30-day mortality rate, with a cut-off of 5.5 days resulting in higher frequency of this adverse event.

CONCLUSION
We found that AKI constitutes an important risk factor for hypoglycaemic episodes in hospitalized diabetic patients, mainly in elderly patients and those with lower baseline GFR. AKI's duration, irrespective of the severity, was the main contributor to higher hypoglycaemia risk. Our data support the need for individualized risk stratification for hypoglycaemic events—we should adapt our clinical practice to prevent or mitigate the impact of these adverse events during hospitalization and after discharge.