Sudden Cardiac Death in Patients with Hypertension. An Association with Diuretics and Beta-blockers?

The cornerstones of current antihypertensive treatment are diuretics and beta-blockers and the efficacy of these drugs in preventing cardiovascular disease is undisputed. This article focuses on the effect of these 2 drug classes on the incidence of sudden death. Numerous studies have shown that thiazide diuretics have a strong, dosage-dependent potassium-depleting effect, and it has been postulated that this may explain why the reduction in risk of coronary heart disease, observed in hypertension trials, was less pronounced than expected. In 7 trials that included sudden death as an end-point; a pooled risk-ratio of sudden death of 1.5 (95% confidence interval 1.1 to 2.0) was observed when non-potassium-sparing diuretics were compared with placebo. Two recent case-control studies have also strongly indicated that the use of thiazides increases the risk of sudden death. Evidence from trials using potassium-sparing diuretic combinations suggests that these may be better tolerated than thiazide monotherapy. Although it was suggested in the 2 recent case-control studies that recipients of beta-blockers are also at an increased risk of sudden death, further studies are required to confirm this finding, particularly since these drugs have several well-documented cardioprotective effects.