Diuretics in long-term treatment of hypertension: a comparison to beta-blockers

Diuretics are first-line drugs for treatment of hypertension in most parts of the world. Recently, however, beta-blockers have been increasingly used as drugs of first choice. The aim of this review is to describe advantages and disadvantages of diuretics in comparison to beta-blockers. The blood pressure (BP)-lowering effect of normally used doses of diuretics gives a useful decrease of BP equal to what can be achieved with beta-blockers in corresponding doses. Over 20 years of use has shown diuretics to be relatively safe for long-term treatment. The frequency of withdrawals and the subjective tolerability are comparable to those with beta-blockers. Diuretics do not seem to induce diabetes or impaired glucose tolerance when used in small doses. At higher doses and in elderly patients impairment of glucose tolerance might appear. The commonly encountered hypokalemia during diuretic treatment seems to be related to the dose and to the duration of the diuretic action. Diuretics can always be used once daily, and they are cheaper than beta-blockers, even when a greater need for laboratory check-ups is taken into account. While beta-blockers so far have not been shown to prevent or postpone hypertensive complications, diuretics have done so in several recent large-scale trials. Two multicenter trials are currently testing the hypothesis of whether beta-blockers are superior to diuretics in preventing coronary heart disease, the most common hypertensive complication. Until these studies are presented, there is little evidence to change the current use of diuretics as first-choice drugs in hypertension.