Acarbose for prevention of diabetes, hypertension and cardiovascular events? A critical analysis of the STOP-NIDDM data

Introduction. Cardiovascular morbidity and mortality is a major and still unresolved threat to patients with reduced glucose tolerance and Type 2 diabetes mellitus. In epidemiological studies, in non-diabetic subjects, post-prandial glycaemia is positively associated with the risk of diabetes, hypertension and cardiovascular events. If this epidemiological association is causal, Acarbose, which reduces post-prandial blood glucose concentrations, should result in a decrease in the risk of these events. The STOP-NIDDM trial investigated whether Acarbose reduces the risk of diabetes, hypertension and cardiovascular events. Consequently, the validity of the results of this trial is of major importance for future treatment in non-diabetic and diabetic patients. Methods. We searched various databases and the Internet for publications of the design and the results of the STOP-NIDDM trial. A systematic review of these publications was done with respect to information about potential sources of bias and contradictory information in the articles. Results. We found several serious flaws in the STOP-NIDDM study, especially selection bias, inadequate blinding, bias in data analysis and reporting, and potential sponsoring bias. Conclusions. The validity of the results of the STOP-NIDDM trial is seriously flawed. The clinical benefit of Acarbose and of the reduction of post-prandial glycaemia is unproven.