Background: Diabetes mellitus represents an independent risk factor for contrast-induced acute kidney injury. We report the results of a prespecified substudy of patients with diabetes mellitus included in the Acetylcysteine for Contrast-Induced Nephropathy Trial (ACT), the largest randomized study evaluating the effects of acetylcysteine for the prevention of contrast-induced acute kidney injury conducted to date.
Methods and results: From the 2308 patients included in the ACT, 1395 had diabetes mellitus and were considered for the present analysis. The study drugs (acetylcysteine 1200 mg or matching placebo) were administered orally twice daily for 2 doses before and 2 doses after the procedure. The allocation was concealed (central Web-based randomization). Participants, healthcare staff, data collectors, and outcome assessors were blinded. All analysis followed the intention-to-treat principle. The incidence of contrast-induced acute kidney injury (primary end point) was 13.8% in the acetylcysteine group and 14.7% in the control group (relative risk 0.93; 95% confidence interval, 0.69-1.26; P=0.64). A combined end point of death or need for dialysis at 30 days was also similar in both the groups (2.2% and 2.1%, respectively; hazard ratio, 1.07; 95% confidence interval, 0.52-2.19; P=0.86).
Conclusions: In this subanalysis, acetylcysteine did not reduce the risk of contrast-induced acute kidney injury or other clinically relevant outcomes in patients with diabetes mellitus undergoing coronary and peripheral vascular angiography.
Clinical trial registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00736866.