Effects of statins on the kidneys in patients with type 2 diabetes

Background Effects of statins on kidneys in diabetic patients remain unclear. Methods This was an observational, historical cohort study of type 2 diabetic patients with estimated glomerular filtration rate (eGFR) >= 30 mL/min/1.73 m(2). We studied 412 patients newly prescribed statins, and 946 controls without a prescription history of statins (including the follow-up period). Outcomes were annual change in eGFR, >= 30 % decrease in eGFR from baseline, and progression of albuminuria, analyzed using a propensity score matching. Results A total of 168 pairs were matched for propensity score. Annual eGFR change (mL/min/1.73 m(2)/year) in the statin group was greater than in controls (-2.24 vs. -1.56, p = 0.024). The hazard ratio of the statin group (vs. controls) for >= 30 % decrease in eGFR and progression of albuminuria was 1.74 (p = 0.082) and 0.85 (p = 0.624), respectively. When the statin group was classified by differences in statin solubility, eGFR change and hazard ratio for >= 30 % decrease in eGFR in the lipophilic statin group were greater than in controls (-2.64 vs. -1.71, p = 0.031 and 2.15, p = 0.049); however, the outcomes in the hydrophilic statin group were not different (-2.35 vs. -1.71, p = 0.106 and 1.08, p = 0.827). The hazard ratio of lipophilic and hydrophilic statin group (vs. controls) for progression of albuminuria was 1.31 (p = 0.552) and 0.69 (p = 0.367). In the analyses using the unmatched cohort, similar results were obtained. Conclusions Statins have no beneficial effects on kidneys in diabetic patients. In fact, lipophilic statins might have potential harmful effects on kidney function.