Current position of calcium antagonists in hypertension

Periodically in the history of antihypertensive therapy, minor storms have significantly affected the use of entire classes of agents. An early example is the publication of case-control studies suggesting that reserpine was associated with increased risk of carcinoma of the breast, a claim subsequently disproved by a number of other studies.

A new controversy has developed recently with the publication of a case-control study report and a non-randomized cohort study which have questioned the use of calcium antagonists in hypertension. The case-control study suffers from the same disadvantages as the reserpine report and, indeed, another case-control study published in 1995, though not so well publicized, reached exactly opposite conclusions, claiming that calcium antagonists were significantly less associated with myocardial infarction than traditional antihypertensive therapy. A meta-analysis has also been presented in support of the non-randomized studies questioning the safety of calcium antagonists. However, this study refers to patients with coronary heart disease, not to patients with hypertension, and also suffers from lumping studies performed with different aims and using data from short-term and long-term studies on short-acting formulations of calcium antagonists.

The controversy generated by these reports has gone well beyond their scientific merit. Well designed prospective studies are needed, and several of these are under way at present. For the time being there is no reason to change the current practice of antihypertensive therapy, as summarized in the recommendations of both the United States Joint National Committee and the World Health Organization/International Society of Hypertension Committee, that diuretics and beta-blockers are among those antihypertensive agents with more clearly proven benefit on the basis of mortality-morbidity studies, while calcium antagonists, angiotensin converting enzyme inhibitors and alpha-blockers can also be profitably used in the treatment of hypertension.