Comparison of the Hypoglycemic Effect of Acarbose Monotherapy in Patients With Type 2 Diabetes Mellitus Consuming an Eastern or Western Diet: A Systematic Meta-analysis

Background: Because of its mechanism of action, the starch content of a diet might alter the hypoglycemic effect of acarbose. Objective: We aimed to determine whether differences in this hypoglycemic effect existed between individuals consuming Eastern and Western diets with significantly different starch contents, a systematic meta-analysis of studies comparing acarbose with placebo or other hypoglycemic agents in patients with type 2 diabetes mellitus (T2DM) was performed. Methods: Records were retrieved from the Cochrane clinical controlled trials, MEDLINE, EMBASE, Wanfang, Chinese Technical Periodicals, and ongoing trials databases, and full texts and reference lists were screened. Because no study has directly compared patients consuming different types of diet, fixed- and random-effect models were used to indirectly compare the hypoglycemic effect of acarbose monotherapy with that of placebo and/or comparator drugs in patients with T2DM consuming an Eastern (Eastern Asia) or Western (including Europe and North America) diet. Results: A total of 46 studies were included in the meta-analysis. The results revealed that, compared with placebo, hemoglobin A(1c) (HbA(1c)) levels were reduced to a significantly greater extent (1.02%) in the Eastern diet (mean [SD], 1.54% [2.00%]) than in the Western diet (mean [SD], 0.52% [1.20%]) P < 0.00001). The ability of acarbose to reduce HbA(1c) levels in the Eastern (P = 0.20) and Western (P = 0.10) diet groups was similar to that of sulfonylureas, and HbA(1c) levels were reduced significantly more (0.39%; P < 0.00001) in the Eastern than in the Western diet group. The ability of acarbose to reduce HbA(1c) levels was similar to those of metformin and nateglinide/repaglinide, but a comparison of its efficacy with different diets was difficult because of the inclusion of few studies in these categories. Analysis of all included studies revealed that acarbose achieved a greater absolute reduction of HbA(1c) levels in the Eastern diet (mean [SD], 1.26% [1.20%]) than in the Western diet (mean [SD], 0.62% [1.28%]; P < 0.00001) group. However, the poor quality of Eastern diet trials may have affected the outcomes of the meta-analysis. Conclusion: The hypoglycemic effect of acarbose is superior in patients with T2DM consuming an Eastern diet than in those consuming a Western diet and is similar to that of sulfonylureas, metformin, and glinide drugs. (C) 2013 Elsevier HS Journals, Inc. All rights reserved.