Hypertension: are beta-blockers and diuretics appropriate first-line therapies?

OBJECTIVE: To review the existing data on the use of diuretics or beta-blockers as first-line therapy for the treatment of mild to moderate hypertension, and to examine the issues surrounding the impact of these classes as well as the angiotensin-converting enzyme (ACE) inhibitors, calcium-channel blockers (CCBs), alpha-blockers, and alpha-beta-blockers on cardiovascular risk factors and cardiovascular morbidity and mortality. DATA SOURCES: A MEDLINE search of applicable articles on antihypertensive therapies and their impact on morbidity and mortality. In addition, a MEDLINE search of relevant articles regarding cardiovascular risk factors and the influence of the various antihypertensive therapies on these parameters. DATA SYNTHESIS: The literature was evaluated with regard to outcome. Trials examining the impact of antihypertensive pharmacotherapy, primarily with diuretics and beta-blockers, have shown them to decrease the incidence of stroke by 33-50 percent. However, their effect on coronary heart disease has been disappointing, showing only a 14 +/- 5 (mean +/- SD) percent decrease. Examination of numerous clinical trials assessing the impact of the various antihypertensive therapies on cardiovascular risk factors, including blood pressure, plasma lipids, diabetic control/insulin sensitivity, and left ventricular hypertrophy was done. The classes included beta-blockers, diuretics, alpha-blockers, ACE inhibitors, and CCBs; the results show a diversity of effect. Diuretics and beta-blockers tend to worsen cardiovascular risk status, whereas the alpha-blockers, ACE inhibitors, and CCBs all show a beneficial effect. CONCLUSIONS: Diuretics and beta-blockers can effectively reduce cerebrovascular morbidity and mortality, but have a limited effect on reducing cardiovascular disease, especially myocardial infarction. This may be explained, at least in part, by the negative, or lack of positive, effect on individual patients' overall cardiovascular risk status.