Antihypertensive therapy in type 2 diabetes: implications of the appropriate blood pressure control in diabetes (ABCD) trial

Abstract

As the population ages, the incidence of type 2 diabetes will increase as will the incidence of concomitant vascular complications. Hypertension substantially increases the risk of cardiovascular disease in patients with diabetes. Results from the recent Appropriate Blood Pressure Control in Diabetes (ABCD) trial demonstrated an advantage of an angiotensin-converting enzyme (ACE) inhibitor (enalapril) over a long-acting calcium antagonist (nisoldipine) with regard to the incidence of cardiovascular events over a 5-year follow-up period in hypertensive persons with type 2 diabetes. This trial was a prospective, randomized, blinded study comparing the effects of moderate blood pressure control (target diastolic pressure 80-89 mm Hg) with those of intensive control (target diastolic pressure 75 mm Hg) on the incidence and progression of diabetic vascular complications. The study also compared nisoldipine with enalapril as first-line antihypertensive therapy in terms of prevention and progression of complications of diabetes. In 470 hypertensive patients, the incidence of fatal and nonfatal myocardial infarctions was significantly (p = 0.001) higher among those receiving nisoldipine (n = 25) compared with those receiving enalapril (n = 5). Comparison with previous studies suggests that the difference observed between nisoldipine and enalapril resulted from a beneficial effect of enalapril rather than a deleterious effect from nisoldipine. Since these findings in the ABCD trial are based on a secondary endpoint, they require confirmation. Nevertheless, they suggest that ACE inhibitors should be the initial antihypertensive medication used in patients with type 2 diabetes and hypertension.