Circulating Betatrophin in Patients with Type 2 Diabetes: A Meta-Analysis

OBJECTIVE To investigate the association between circulating betatrophin level and type 2 diabetes mellitus (T2DM) in human. METHODS A comprehensive literature search was performed in PubMed and Embase databases to identify eligible studies assessing the circulating levels of betatrophin in both T2DM patients and nondiabetic adults. RESULTS A total of nine eligible studies with twelve comparisons were included for the final meta-analysis. Circulating betatrophin levels in T2DM patients were higher than those in the nondiabetic controls (random-effect SMD 0.53; 95% CI 0.13 to 0.94; P = 0.010). In the subgroup of nonobese population but not the obese population, the overall betatrophin level in T2DM patients was much higher than that in the nondiabetic controls (nonobese: random-effect SMD, 0.82; 95% CI 0.42 to 1.21; P < 0.001; obese: random-effect SMD, -0.39; 95% CI, -0.95 to 0.18; P = 0.18). Metaregression indicated that body mass index of T2DM patients was associated with mean difference of betatrophin level between T2DM and nondiabetic adults (slope, -578.8; t = -2.7; P = 0.02). CONCLUSION Based on the findings of our meta-analysis, circulating betatrophin level of T2DM patients is higher than that of nondiabetic adults in the nonobese population, but not in the obese population.