Short-term and long-term effects of dipeptidyl peptidase-4 inhibitors in type 2 diabetes mellitus patients with renal impairment: a meta-analysis of randomized controlled trials

To assess the short-term and long-term effects of dipeptidyl peptidase-4 (DPP-4) inhibitors in type 2 diabetes mellitus patients with renal impairment, a meta-analysis of randomized clinical trials of DPP-4 inhibitor interventions in type 2 diabetes mellitus patients with renal impairment was performed. PubMed, Embase, Cochrane Library and ClinicalTrials.gov were searched through the end of March 2015. Randomized clinical trials were selected if (1) DPP-4 inhibitors were compared with a placebo or other active-comparators, (2) the treatment duration was >= 12 weeks and (3) data regarding changes in haemoglobin A(1c) (HbA(1c)), changes in fasting plasma glucose or hypoglycaemia and other adverse eventswere reported. Of 790 studies, ten studies on eight randomized clinical trials were included. Compared with the control group, DPP-4 inhibitors were associated with a greater HbA(1c) reduction in both the short-term[mean differences (MD) = -0.45, 95% confidence intervals (-0.57, -0.33), p<0.0001] and long-term [MD = -0.33, 95% confidence intervals (-0.63, -0.03), p=0.03] treatments. However, the long-term greater reduction in HbA(1c) with DPP-4 inhibitor treatment was only significant when the control treatment comprised placebo plus stable background treatment, but not glipizide plus stable background treatment. DPP-4 inhibitors were associated with a greater fasting plasma glucose reduction [MD = -12.59, 95% confidence intervals (-22.01, -3.17), p=0.009] over the short-term; however, this effect was not present over the long-term. Regarding the hypoglycaemia adverse events assessment, the long-term treatment data indicated there was no increased risk of hypoglycaemia compared with placebo or active-controlled anti-diabetic drugs. The present meta-analysis confirms that DPP-4 inhibitors are effective and equivalent to other agents in type 2 diabetes mellitus patients with renal impairment. Copyright (C) 2015 John Wiley & Sons, Ltd.