Plasma renin activity does not predict the antihypertensive efficacy of chlorthalidone

Thiazide diuretics in the treatment of hypertension: an update

Thiazide diuretics were the first tolerated efficient antihypertensive drugs that significantly reduced cardiovascular morbidity and mortality in placebo-controlled clinical studies. Although these drugs today still are considered a fundamental therapeutic tool for the treatment of hypertensive patients, the following considerations should be taken into account. Although there are some indications that chlorthalidone can offer additional advantages as compared with other compounds, a recent meta-analysis of placebo-controlled trials suggested that the beneficial effects of thiazide diuretics could be a class effect. Thiazide diuretics must be used at appropriate and/or optimal doses to achieve the optimal antihypertensive effect with the smallest occurrence of side effects, including alterations in glucose and lipid profiles and hypokalemia. Moreover, because thiazide diuretics can increase the incidence of new-onset diabetes, especially when combined with beta blockers, caution is advised in using these drugs above all in patients who are at high risk for developing diabetes, in whom thiazide diuretics should be used at the lowest active dose and possibly in combination with drugs that block the renin-angiotensin system. Finally, the current debate on whether thiazide diuretics are the first-choice drug for most patients with uncomplicated hypertension, as stated in the Seventh Joint National Committee Report, or are included in the major classes of antihypertensive agents that are suitable for initiation and maintenance of therapy, as reported in the European Society of Hypertension-European Society of Cardiology Guidelines, derives from different interpretations of controlled clinical trial data on drug class comparison and of cost-benefit analyses. However, considering that the benefit of antihypertensive drugs seems to be due principally to BP lowering per se without definitive evidence of the superiority of a particular drug class and that there is no cost-benefit analysis showing the superiority of thiazide diuretics, it is believed that these drugs should not be considered as the only first-choice drug but included among first-choice drugs.

Chlorthalidone alone or in fixed combination with slow-release metoprolol in the management of arterial hypertension: a long-term study of 545 patients

In a double-blind trial, 545 out-patients with essential hypertension received 25 mg/day chlorthalidone alone (274 patients) or in fixed combination with 200 mg/day slow-release metoprolol (271 patients) for 8 weeks. Both treatments significantly (P less than 0.001) decreased systolic and diastolic blood pressure; 45.6% of patients receiving chlorthalidone and 82.5% receiving combined therapy had a diastolic blood pressure of less than 95 mmHg. Patients not controlled by chlorthalidone or chlorthalidone plus metoprolol subsequently received chlorthalidone plus metoprolol (137 patients) or chlorthalidone plus metoprolol plus a third drug (34 patients), respectively, for 8 weeks. A total of 79.5% of patients receiving chlorthalidone plus metoprolol and 61.8% receiving chlorthalidone plus metoprolol plus a third drug had a diastolic blood pressure of less than 95 mmHg. Only 5.9% of patients experienced mild to moderate side-effects. Plasma potassium levels significantly (P less than 0.01) decreased during the first 8 weeks only. It is concluded that a diuretic alone or in fixed combination with a beta-blocker is effective in the long-term treatment of arterial hypertension.