Acarbose Monotherapy and Type 2 Diabetes Prevention in Eastern and Western Prediabetes: An Ethnicity-specific Meta-analysis

Abstract Purpose Acarbose is effective in delaying or preventing the progression of prediabetes to type 2 diabetes mellitus (T2DM). The aim of this study was to assess differences in the preventive effects of acarbose in Eastern and Western populations with prediabetes. Methods We performed a systematic search of databases and reference lists of clinical trials conducted through August 2013. Randomized controlled trials of acarbose alone, with a minimum intervention duration of 3 years and which provided data on T2DM incidence, were included for analysis. Analyses were conducted by using Review Manager version 5.1 software. Findings Eight randomized controlled trials with 2628 participants were included. Acarbose decreased the occurrence of T2DM (number needed to treat [NNT], 6.7). Compared with the control (placebo and/or lifestyle intervention), the incidence of T2DM was significantly lower in the Eastern group (NNT, 5.9) than in the Western group (NNT, 11.1) ( P < 0.0001, I2 = 94.7%). At the end of follow-up, reversal of prediabetes to normal glucose tolerance was more likely in the Eastern group (NNT, 4.3) than in the Western group (NNT, 25) ( P = 0.004, I2 = 92%). Among those remaining prediabetic, there was no significant difference between the subtotal estimates for the subgroups ( P = 0.17, I2 = 46.5%). There was no positive correlation between preventive effect and dose, and no difference in studies with varying follow-up durations within and across either ethnic group. Implications The preventive effect of acarbose on the development of diabetes seems superior in Eastern populations with prediabetes compared with Western populations.