Does spironolactone reduce blood pressure more effectively than a hydrochlorothiazide-triamterene combination in patients with low-renin essential hypertension?
Both spironolactone and hydrochlorothiazide-triamterene effectively lower blood pressure in low-renin essential hypertension, suggesting that extracellular fluid volume reduction is the primary mechanism of benefit.
Seventeen patients with low-renin essential hypertension were studied in a double-blind comparison of the antihypertensive effect of spironolactone with that of a hydrochlorothiazide-triamterene combination. All 17 patients responded to spironolactone. The decrease in average mean blood pressure was 20.7 mm Hg accompanied by an average diuresis of —3.1 kg. Fourteen of the 17 patients had favorable responses to hydrochlorothiazide-triamterene. The average decrease in mean blood pressure was 17.0 mm Hg, and the average diuresis was —1.5 kg. The difference in mean blood pressure response was not statistically significant. The fact that both forms of therapy were effective, even though their mechanisms of action differ, suggests that extracellular fluid volume reduction may be the key factor in the amelioration of hypertension in patients with "low-renin essential hypertension."
J. G. Douglas (Mon,) studied this question.