Background: Two new classes of antihypertensive agents were introduced in the 1980s, but their effectiveness in preventing heart disease and stroke has not been demonstrated. Lack of evidence of their efficacy might reasonably be expected to discourage their widespread use in management of hypertension.
Methods: Use of various classes of antihypertensive agents was estimated from published drug use information in an effort to estimate trends in antihypertensive drug use and evaluate the impact of these trends on costs of antihypertensive therapy in the United States.
Results: Proportionate use of the five major antihypertensive drug classes shifted markedly between 1982 and 1993. Diuretics accounted for 56% of all hypertensive drug mentions in 1982 but only 27% in 1993, a relative decline of 52%. Use of beta-blockers and central agents also declined during this period. Proportionate use of calcium antagonists showed the greatest gains, increasing from 0.3% to 27%, while the use of angiotensin-converting enzyme inhibitors increased from 0.8% to 24%. Given the higher costs of the newer agents, and assuming an estimated total cost of antihypertensive medications in 1992 of $7 billion, approximately $3.1 billion would have been saved had 1982 prescribing practices remained in effect in 1992.
Conclusions: Use of calcium antagonists and angiotensin-converting enzyme inhibitors in hypertension has increased dramatically in the past 10 years. Without convincing evidence of the advantages of these agents, it is difficult to explain the continued decline in the use of less expensive agents, such as diuretics and beta-blockers, which are the only antihypertensive agents proved to reduce stroke and coronary disease in hypertensive patients.