Urinary albumin excretion with sitagliptin compared to sulfonylurea as add on to metformin in type 2 diabetes patients with albuminuria: A real-world evidence study

Abstract

Aim: To compare the change in urinary albumin to creatinine ratio (UACR) in type 2 diabetes (T2DM) patients with albuminuria who initiate sitagliptin to those who initiate a sulfonylurea (SU) as add-on to metformin monotherapy.

Method: A cohort of T2DM patients with albuminuria (UACR >30mg/g) who initiated sitagliptin or SU as add-on dual therapy to metformin between 2008 and 2014 was extracted from the computerized medical records of a large managed care organization in Israel. Patients with albuminuria and UACR measurements available at treatment initiation and 120-365days afterwards were included. Propensity scores were calculated based on 17 factors, including demography, comorbidities, baseline levels of HbA1c, UACR, BMI, eGFR, and ACE/ARB use, and patients were matched in a 1:1 ratio. Changes in UACR were compared between the matched pairs using generalized estimating equations.

Results: A total of 282 eligible pairs (sitagliptin:SU) were identified. During a mean follow-up of 9months, median UACR changes were -35% (IQR=-73% to 5%) and -31% (IQR=-72% to 21%) in the sitagliptin and SU groups, respectively. Mean absolute HbA1c reductions among sitagliptin and SU groups were 0.9% and 1.0%, respectively. The magnitude of UACR reduction generally increased with greater magnitude of HbA1c reduction in both treatment groups. However, after controlling for HbA1c reduction and the interaction between HbA1c reduction and UACR reduction, sitagliptin users demonstrated a trend toward an increased likelihood of UACR reduction compared to SU users (odds ratio=1.20; 95% confidence interval: 0.99-1.47, P=0.063).

Conclusion: Our results suggest that both sitagliptin and SU reduce albuminuria as an add-on therapy to metformin, but that sitagliptin may provide greater reductions in albuminuria independent of glycemic control when compared to SU. Larger population studies are required to further explore this.

Keywords: Albuminuria; DPP-4 inhibitors; Nephropathy; Sitagliptin; Sulfonylurea.