Glucose metabolism and calcium antagonists

High blood pressure, but also diabetes mellitus and even glucose intolerance are well known risk factors for premature cardiovascular morbidity and mortality. To counteract these sequelae, it is obvious that drug treatment of hypertension should not adversely affect the glucose homeostasis in nondiabetic as well as in diabetic patients. Therefore, the findings that calcium antagonists could dose-dependently throttle the insulin output after addition of glucose in pancreas perfusion experiments in vitro were of considerable concern. Within the last years, most of more than 100 short-term and long-term trials in diabetic and non-diabetic patients were able to show that different calcium antagonists at their "usual" antihypertensive dosages did not impair the glucose metabolism, whereas results of acute studies, especially with higher doses and after a glucose challenge, were more controversial. However, in all of the 13 long-term follow-up trials (up to 5 years) with determinations of the glycated hemoglobin published to date, this most relevant parameter remained unchanged. Thus, currently available data indicate that calcium antagonists do not alter glucose handling at a clinically relevant degree, both in non-diabetic or diabetic patients, so that it is not justified to withhold the benefits of these medications from hypertensives out of fear to introduce a deterioration in their carbohydrate homeostasis.