[Current pharmaco-therapeutic strategies in the treatment of arterial hypertension].
The aim of the treatment of hypertensive disease is to reduce its associated cardiovascular morbidity and mortality. Simply reducing blood pressure levels is clearly not adequate since its impact on coronary heart disease is particularly unsatisfactory. Moreover, the beneficial effects of antihypertensive treatment seem to plateau for several years, and the incidence of cardiac and renal failure is even increasing. Therefore, recommendations by groups of national or international experts are periodically updated on the basis of current epidemiological data. Two such recommendations appeared in 1997, one from the Agence Nationale d'Accréditation et d'Evaluation en Santé (ANAES) in France and the other from the Joint National Committee (JNC) on Prevention, Detection, Evaluation and Treatment of High Blood Pressure, in the United States. Both advocate the use of lifestyle modifications in all patients. The threshold blood pressure level at which pharmacological therapy is introduced largely depends on associated cardiovascular risk factors and/or involvement of target organs. The JNC recommends a particularly low threshold in patients with diabetes. Pharmacological treatment is usually initiated with a single drug. The choice of any one drug depends on the patient profile and takes into consideration such characteristics as age and associated risk factors or comorbidity. Some represent a contraindication for certain therapeutic classes (for example, asthma for beta-blockers, renovascular hypertension for ACE inhibitors), while others are a specific or even 'compelling' indication (heart failure, angina, renal disease, peripheral vascular disease etc.). This patient profiling is very precisely described in the new recommendations. However, any such single drug therapy provides adequate blood pressure control in no more than about 50 to 60% of patients. When the patient does not respond to the drug used or experiences side effects, substitution of a drug from another pharmacological class is recommended. In contrast, if the patient is a responder but blood pressure remains above the target level, it is preferable to add a second drug from a class offering complementary action. The use of a combination therapy allows blood pressure control in more than 80% of patients. More authors are suggesting that combination therapy as first-line treatment may increase the number of responders and reduce the impact of counter-regulatory effects occurring with single drug therapy (e.g. sodium retention, or sympathetic activation). This alternative strategy is now acknowledged in the recommendations.