First-line treatment for hypertension

Published online 28 November 2001. Recent guidelines for hypertension management differ in their recommendations for routine firstline treatment for hypertension, as have previous generations of guidelines. For example, the United States JNC VI and British Hypertension Society guidelines both recommend low-dose diuretics and beta-blockers as first-line treatment unless there are compelling contraindications or compelling indications for other drug classes. The WHO/ISH guidelines suggest that a wider range of drug classes is suitable for routine first-line treatment. These differences are of considerable importance, because pharmaceutical companies are inevitably keen to promote the more liberal international (WHO/ISH) guidelines even in countries with national guidelines that recommend a different policy. In the short time since the current guidelines were developed and promulgated, a substantial amount of new evidence has emerged from randomized controlled trials. These include trials comparing newer drugs to placebo, trials comparing the outcome with different drug classes, and trials of different intensities of treatment. This new trial evidence has been the subject of several meta-analyses, and these have not always agreed in their conclusions. The purpose of this article is to consider what all the evidence now available, including the new trials and meta-analyses, tells us about the choice of first-line treatment. Before considering the new evidence it is worth restating that the major classes of antihypertensive drug, namely diuretics, beta-blockers, ACE inhibitors, calcium channel blockers, and selective alphablockers, do not differ in any important way as regards their efficacy in reducing blood pressure, simplicity to prescribe or to take, or safety. There is a strong and widely-held prejudice that the newer classes of drugs are better tolerated than diuretics and beta-blockers. This is quite incorrect. Large, long, double-blind comparative studies have shown that diuretics and beta-blockers are tolerated as well as, or better than, the newer drug classes whether measured by the frequency of dropouts, subjective side-effects, or quality of life.