Soichi Kurioka, Yasuo Ohyama, Akira Ichibangase, Hideho Murata, Nobuhiko Kataoka, Hiroaki Shimomura, Hideaki Sawaki, Tamaki Imai, Shinichiro Ohashi
Objective: Previous studies have shown that statins improve kidney function in patients with chronic kidney disease. In this study, we examined the effect of combination therapy (statin and dipeptidylpeptidase IV inhibitor) on kidney function in patients with type 2 diabetes with hypercholesterolemia. Research design and methods: The subjects were 81 patients with type 2 diabetes with hypercholesterolemia, of whom 29 were treated with 50 mg sitagliptin (combination therapy group) and 52 did not receive sitagliptin (control group). The patients received 2 mg pitavastatin for 6 months and the effects on estimated glomerular filtration rate (eGFR), lipid profile, and glycemic control were evaluated. Results: After 6 months of pitavastatin treatment, there was a significant increase in eGFR in the combination therapy group (71.3 ± 23.2 to 84.2 ± 22.7 ml/min/1.73 m2, p<0.001), but not in the control group (73.3 ± 20.1 to 76.1 ± 19.7 ml/min/1.73 m2, p=0.15); and the changes in Cr and eGFR were significantly greater in the combination therapy group. Based on the CKD stage, patients with normal kidney function (G1 and G2) had no significant change in eGFR, but in patients with moderate kidney dysfunction (G3), the improvement in eGFR (from 48.6 ± 7.9 to 62.3 ± 18.9 mL/min/1.73 m2) soon occurred after 1-month of combination therapy and then stabled. In multiple regression analysis, Cr, apoA-1, apoB, and sitagliptin were independently associated with the change in eGFR. Conclusions: These findings suggest that combination therapy of pitavastatin and sitagliptin may have a kidney protective effect in patients with type 2 diabetes with hypercholesterolemia.