Changes in serum lipid levels during antihypertensive therapy.

The antihypertensive action of prazosin and propranolol, as well their effect on serum lipid levels, were evaluated in a crossover study in 20 men with untreated mild to moderate hypertension in a general practice environment. Both prazosin (7.5 +/- 0.5 mg/day) and propranolol (270 +/- 26 mg/day) produced a similar reduction in blood pressure over an eight-week period. The administration of propranolol also led to a reduction of the mean fasting high-density lipoprotein cholesterol concentration by 10.5% (P less than 0.01) and this effect was dose-related (r = -0.414; P less than 0.05). Prazosin treatment produced no changes either in the total or in the high-density lipoprotein cholesterol levels, but led to a reduction of the total triglyceride levels by 9.5% (P less than 0.05). These results suggest that the value of blood pressure reduction produced by high doses of beta-adrenoceptor blocking agents, such as propranolol, may be diminished by a potentially adverse effect of these agents on serum lipid levels. Conversely, alpha-adrenoceptor blocking agents may confer an added benefit in the treatment of hypertension.