Hypoglycemia-Related Hospitalizations and Mortality Among Patients With Diabetes Transitioning to Dialysis

Rationale & Objective: Diabetic patients with declining kidney function are at heightened risk for hypoglycemia. We sought to determine whether hypoglycemia-related hospitalizations in the interval before dialysis therapy initiation are associated with post-end-stage renal disease (ESRD) mortality among incident patients with ESRD with diabetes. Study Design: Observational cohort study. Setting & Participants: US veterans from the national Veterans Affairs database with diabetes and chronic kidney disease transitioning to dialysis therapy from October 2007 to September 2011. Exposure: Hypoglycemia-related hospitalizations during the pre-ESRD period and antidiabetic medication regimens. Outcome: The outcome of post-ESRD all-cause mortality was evaluated relative to pre-ESRD hypoglycemia. The outcome of pre-ESRD hypoglycemia-related hospitalization was evaluated relative to antidiabetic medication regimens. Analytic Approach: We examined whether the occurrence and frequency of pre-ESRD hypoglycemia-related hospitalizations are associated with post-ESRD mortality using Cox regression models adjusted for case-mix covariates. In a subcohort of patients prescribed 0 to 2 oral antidiabetic drugs and/or insulin, we examined the 12 most commonly prescribed antidiabetic medication regimens and risk for pre-ESRD hypoglycemia-related hospitalization using logistic regression models adjusted for case-mix covariates. Results: Among 30,156 patients who met eligibility criteria, the occurrence of pre-ESRD hypoglycemia-related hospitalization(s) was associated with higher post-ESRD mortality risk: adjusted HR (aHR), 1.25; 95% CI, 1.17-1.34 (reference group: no hypoglycemia hospitalization). Increasing frequency of hypoglycemia-related hospitalizations was independently associated with incrementally higher mortality risk: aHRs of 1.21 (95% CI, 1.12-1.30), 1.47 (95% CI, 1.19-1.82), and 2.07 (95% CI, 1.46-2.95) for 1, 2, and 3 or more hypoglycemia-related hospitalizations, respectively (reference group: no hypoglycemia hospitalization). Compared with patients who were prescribed neither oral antidiabetic drugs nor insulin, medication regimens that included sulfonylureas and/or insulin were associated with higher risk for hypoglycemia. Limitations: Residual confounding cannot be excluded. Conclusions: Among incident patients with ESRD with diabetes, a dose-dependent relationship between frequency of pre-ESRD hypoglycemia-related hospitalizations and post-ESRD mortality was observed. Further study of diabetic management strategies that prevent hypoglycemia as patients with chronic kidney disease transition to ESRD are warranted.