Angiotensin converting enzyme inhibition in clinical practice. Choice of initial treatment.

An important consideration in the choice of initial treatment is race. In a Veterans Administration study nadolol reduced blood pressure more in whites than in blacks, while the reverse was true with hydrochlorothiazide. Combining both drugs enhanced antihypertensive effectiveness and abolished the racial difference. The results of this and other studies suggest that for first drug selection, beta-blockers are indicated in whites and diuretics in blacks. Beta-blockers are also indicated in all patients with prior myocardial infarction or with tachycardia. Thiazides are also used in combination with other antihypertensive drugs and in patients with heart failure. Reluctance to use thiazide diuretics stems from the possibility of hypokalemia-induced arrhythmias and long-term elevations of serum cholesterol. However, a causal relationship between hypokalemia and the incidence of arrhythmias is not well supported by physiologic or clinical evidence. Elevation of cholesterol appears to be transient, reverting back to pretreatment levels after 6-12 months of treatment. An alternative regimen which is both highly effective and well tolerated is the combination of small doses of both a thiazide diuretic and captopril. Perhaps less well tolerated, but useful where cost is the major consideration, is a thiazide followed by small doses of reserpine, if needed; this is an effective, low-cost treatment. Calcium channel blockers appear promising but require further evaluation.