Background and objectives Sitagliptin, a dipeptidylpeptidase-4 inhibitor, is commonlyprescribed to patientswith type 2 diabetes. As this drug is primarily eliminated by the kidney, a reduced dose is recommended for patients with CKD. Some evidence suggests that sitagliptin is associated with a higher risk of congestive heart failure, particularly at higher doses.Wecompare the 1-year risk of death or hospitalizationwith congestive heart failure in patients with CKD newly prescribed sitagliptin at \u3c50 versus ≤50 mg/d. Design, setting, participants, & measurements This population-based cohort study included older adults (\u3e66 years) with type 2 diabetes and an eGFR\u3c45 ml/min per 1.73 m2 (but not receiving dialysis) who were newly prescribed sitagliptin between 2010 and 2017 in Ontario, Canada. We used inverse probability of treatment weighting on the basis of propensity scores to balance baseline characteristics. The primary composite outcome was death or hospitalization with congestive heart failure. Secondary outcomes included hospitalization with pancreatitis or hypoglycemia, all-cause hospitalization, and glycemic control. Weighted hazard ratios were obtained using Cox proportional hazards regression, and 95%confidence intervalswere obtained using bootstrap variance estimators. Results Of 9215 patients, 6518 started sitagliptin at \u3e50 mg/d, and 2697 started sitagliptin at ≤50 mg/d. The 1-year risk of death or hospitalization with congestive heart failure did not differ significantly between groups (79 versus 126 events per 1000 person-years; weighted hazard ratio, 0.88; 95% confidence interval, 0.67 to 1.14); hospitalization with pancreatitis (weighted hazard ratio, 0.98; 95% confidence interval, 0.32 to 3.03) and hypoglycemia (weighted hazard ratio, 1.10; 95% confidence interval, 0.64 to 1.90) also did not differ significantly between groups. Patients starting sitagliptin at \u3e50 mg/d had lower mean glycated hemoglobin concentrations (weighted between-group difference, 20.12%; 95% confidence interval, 20.19 to 20.06) and a lower risk of allcause hospitalization (weighted hazard ratio, 0.81; 95% confidence interval, 0.66 to 0.98). Conclusions The risk of death or congestive heart failure was not higher in older adults with CKD starting sitagliptin at \u3e50 versus ≤50 mg/d
