Should calcium antagonists be first-line agents in the treatment of cardiovascular disease? The public health perspective.

The calcium antagonist (CA) controversy has been fueled in part by disagreements among scientists and clinicians over the scientific documentation required for drugs used to treat lifelong conditions. From a public health perspective, there are three unanswered questions: (1) Does long-term use of CAs convey health benefits to patients with cardiovascular disease (CVD)? (2) Is the long-term use of CAs safe? (3) Is the use of CAs cost effective? The answers to these questions determine the pertinence of three secondary questions: (4) Do the effects of CAs reflect a class action or are there important differences in health outcomes among subclasses of CAs? (5) Are the short-acting, immediate-release (IR) formulations different from the long-acting or the slow-release (SR) formulations? (6) What is prudent use of CAs? The purpose of this report is to summarize the answers to these questions from a public health perspective. (1) To date, use of CAs has not been documented to reduce the risks of cardiovascular complications of hypertension-stroke, myocardial infarction, congestive heart failure, or renal dysfunction. (2) The clinical trial database is inadequate to determine the long-term safety of CAs. The available data suggest that some formulations of CAs may be associated with an increased risk of cardiovascular and noncardiovascular events. (3) Even if slow-release CAs conveyed a benefit, their cost-effectiveness ratios are unlikely to be acceptable. (4) The non-dihydropyridines may offer an advantage over the dihydropyridines. (5) Whether the slow-release formulations differ from the immediate-release formulations in terms of their health effects remains to be seen. (6) It may be prudent clinically to restrict the use of CAs until proper documentation of long-term safety and efficacy and cost effectiveness is available.