Calcium antagonists and the diabetic patient: a response to recent controversies

The results of 2 recently published studies have been interpreted as suggesting that calcium antagonists are unsafe for the management of hypertension in patients with diabetes. These 2 studies, the Fosinopril versus Amlodipine Cardiovascular Events Randomized Trial (FACET) and Appropriate Blood Pressure Control in Diabetes (ABCD), showed that angiotensin-converting enzyme (ACE) inhibitors may be preferable to calcium antagonists for managing hypertension in diabetic patients; they do not, however, show any harm attributable to calcium antagonists. Indeed, results of the FACET study suggest that the combination of an ACE inhibitor and a calcium antagonist is effective antihypertensive therapy. This suggestion is supported by findings in the Systolic Hypertension in Europe (Syst-Eur) Study, which revealed outstanding benefits of either a calcium antagonist alone or a calcium antagonist combined with an ACE inhibitor among diabetic patients with hypertension. The premature termination of the hypertensive arm of the ABCD study was puzzling because, although 2 of 13 subgroups of 1 of the 5 possible secondary endpoints in this part of the trial were apparently favorably affected by the use of the ACE inhibitor rather than the calcium antagonist, such a finding was compatible with chance alone. If the results of the FACET and ABCD studies are considered in the context of the best available data arising from large randomized controlled trials, one may conclude that calcium antagonists are not harmful or contraindicated in hypertensive patients with diabetes and that the combination of an ACE inhibitor and a calcium antagonist is effective for the management of hypertension in diabetic patients.