The Effect of Weight Reduction on Blood Pressure, Plasma Renin Activity, and Plasma Aldosterone Levels in Obese Patients

TLDR

The study aimed to examine how weight loss affects the renin‑aldosterone axis and blood pressure in obese patients. Twenty‑five obese patients followed a 12‑week weight‑reducing diet with either medium (120 mmol) or low (40 mmol) sodium intake, and changes in PRA, aldosterone, and blood pressure were measured. Weight loss produced significant reductions in plasma renin activity and aldosterone, with mean arterial pressure falling in parallel; reductions in PRA correlated with weight loss and blood pressure decline regardless of sodium intake. Published in N Engl J Med 1981; 304:930–3.

Abstract

We investigated the relation between changes in the renin-aldosterone axis and reduction in blood pressure in 25 obese patients placed on a 12-week reducing diet; sodium intake was either medium (120 mmol) or low (40 mmol). Plasma renin activity (PRA) declined with weight loss, so that by 12 weeks there was a significant decrease in PRA (P<0.01) as well as plasma aldosterone (P<0.05), regardless of sodium intake. Weight loss with low sodium intake was equal to that with medium intake. The reduction in PRA but not in aldosterone correlated with weight loss in both sodium-intake groups (r = 0.58). Mean arterial pressure fell significantly and equally in both groups, correlating with weight loss throughout the study (r = 0.56) and with PRA from the fourth through 12th weeks (r = 0.48). These results demonstrate that weight loss is accompanied by reductions in PRA and aldosterone; PRA reductions, irrespective of sodium intake, may contribute to the decline in blood pressure. (N Engl J Med. 1981; 304:930–3.)