Comparative effectiveness of sulfonylureas on kidney outcomes in adults with type 2 diabetes and moderate cardiovascular risk: a target trial emulation.

introductionTo assess the within-class variation in kidney outcomes following initiation of sulfonylurea therapy. RESEARCH DESIGN AND

methodsWe used claims data of enrollees in commercial, Medicare Advantage, and traditional Medicare health plans between 2014 and 2021 to emulate a target trial including adults ≥21 years with type 2 diabetes at moderate cardiovascular risk to compare initiation of glimepiride, glipizide, or glyburide on the incidence of chronic kidney disease (CKD) stage 3 or worse, including initiation of kidney replacement therapy (primary outcome); secondary outcomes examined incident CKD stages 3-4, kidney failure (including kidney replacement therapy), all-cause mortality, and hypoglycemia requiring emergency department or hospital care. Random treatment assignment was emulated using propensity scores, estimated using the super learner ensemble method, and incorporated as inverse probability of treatment weights into proportional hazards models.

resultsThe weighted study cohort included 295 092 individuals starting glimepiride (n=134 926), glipizide (n=145 984), and glyburide (n=14 182). One year after treatment initiation, stage 3 or worse CKD developed in 2.1% of patients in the glimepiride group, 2.2% in the glipizide group, and 1.8% in the glyburide group. Glyburide was associated with a lower risk of kidney complications compared with both glimepiride (HR 0.84, 95% CI 0.76 to 0.92) and glipizide (HR 0.81, 95% CI 0.73 to 0.89), despite a higher risk of severe hypoglycemia (HR 1.47, 95% CI 1.27 to 1.71 vs glipizide and HR 1.22, 95% CI 1.05 to 1.42 vs glimepiride). In contrast, the risk of kidney complications was modestly increased with glipizide compared with glimepiride use (HR 1.04, 95% CI 1.00 to 1.07).

conclusionsGlyburide was associated with a modestly lower risk of kidney complications, despite a higher risk of hypoglycemia, while glipizide was associated with a higher risk of kidney complications. These hypothesis-generating findings suggest important within-class differences that warrant consideration in clinical decision-making and future research. Despite rigorous prespecified causal inference analytic methods, the risk of unmeasured confounding and bias by indication with the use of observational data remains. TRIAL REGISTRATION NUMBER: NCT05214573.