Study Compares Effectiveness of Oral Anti-diabetic Drugs on Kidney Function for Veterans with Type 2 Diabetes
BACKGROUND:
Diabetes is a major cause of chronic kidney disease. In the U.S., diabetes accounts for 45% of incident end-stage renal disease (ESRD). Oral anti-diabetic drugs (OADs) are the mainstay of therapy for most patients with type 2 diabetes; however, few studies have compared the effects of individual OADs on kidney function decline. This retrospective study sought to determine if initial treatment with different OAD monotherapies was associated with differential declines in kidney function. Using VA data, investigators identified a national cohort of 93,577 Veterans with type 2 diabetes who initiated OAD therapy between 2001 and 2008 — and who had normal kidney function at baseline (estimated glomerular filtration rate [eGFR] of >60 ml/min). Veterans in the cohort used one of several OADs, including metformin (n=61,104), sulfonylureas (n=30,550), or rosiglitazone (n=1,923). The median length of follow-up by group was 0.9 years for metformin, 0.8 years for sulfonylureas, and 0.7 years for rosiglitazone. Outcomes were persistent decline of >25% in eGFR from baseline, diagnosis of ESRD, or death.
FINDINGS:
- Among Veterans with type 2 diabetes, initiation of sulfonylureas compared to metformin was associated with an increased risk of clinically significant decline in kidney function, diagnosis of ESRD, or death.
- Compared to metformin, the use of rosiglitazone was not significantly associated with any outcomes. Compared to sulfonylureas, the use of rosiglitazone was associated with a decreased risk for all three outcomes.
- Authors suggest that these findings support the current recommendations of metformin as first-line therapy for patients with type 2 diabetes who are in earlier stages of kidney disease.
LIMITATIONS:
- Data were only available for one-third of the Veterans regarding proteinuria — a key predictor of the progression of chronic kidney disease.
- Some Veterans in this study with reversible acute kidney injury may have been misclassified with chronic kidney disease progression.
AUTHOR/FUNDING INFORMATION:
Dr. Roumie was supported by an HSR&D Career Development Award; she and Dr. Hung are part of the VA Tennessee Valley Geriatric Research Education and Clinical Center (GRECC).
Hung A, Roumie C, Greevy R, et al. Comparative Effectiveness of Incident Oral Anti-diabetic Drugs on Kidney Function: A National Veterans Cohort Study. Kidney International January 18, 2012;e-pub ahead of print.
