Does Twice-weekly Cabergoline Improve Anthropometrical and Biochemical Profiles in Prediabetes? A Randomized Double-blind Clinical Trial Pilot Study

Dopaminergic signaling is one of the regulatory pathways being investigated for its implication in glucose metabolism. The aim of this study was to determine the effect of cabergoline on biochemical and anthropometric parameters in prediabetes stage (impaired fasting glucose and impaired glucose tolerance). In this double blind, placebo-controlled, pilot study, 27 prediabetic adults were randomized to receive 0.25-mg cabergoline twice weekly for two weeks, followed by 0.5 mg twice weekly for next 14 weeks (n = 13) or placebo (n = 14). All subjects were advised to follow a 500 kcal-deficit energy diet. Fasting plasma glucose (FPG), oral glucose tolerance, glycated hemoglobin (A1c), fasting, and 2-h insulin were measured at baseline and at 16-week follow-up. Homeostasis model assessment (HOMA) 2 was calculated to estimate steady-state beta-cell function, insulin sensitivity, and insulin resistance. Our results showed significant reductions in fasting (P = 0.004) and 2-h plasma glucose (P = 0.01) after treatment, and significant improvements in beta-cell function (P = 0.03) and insulin resistance (P = 0.04) in the cabergoline group. The trend of non-significant A1c changes was decreasing in the cabergoline group versus an increasing trend in the placebo group. All anthropometric parameters were similar between the two groups. Our results revealed that twice-weekly cabergoline could improve glucose metabolism in prediabetes stage. Larger studies of longer duration are warranted to investigate the effect of cabergoline in preventing progression of prediabetes to type 2 diabetes mellitus.