The long-term effects of dietary sodium restriction on clinical outcomes in patients with heart failure. The SODIUM-HF (Study of Dietary Intervention Under 100 mmol in Heart Failure): A pilot study

Abstract

To determine the feasibility of conducting a randomized controlled trial comparing a low-sodium to a moderate-sodium diet in heart failure (HF) patients. Patients with HF (New York Heart Association classes II-III) were randomized to low (1500 mg/d) or moderate-sodium (2300 mg/d) diet. Dietary intake was evaluated using 3-day food records. The end points were changes in quality of life as measured by the Kansas City Cardiomyopathy Questionnaire (KCCQ) scores and B-type natriuretic peptide (BNP) levels from baseline to 6 months of follow-up presented as medians [25th, 75th percentiles]. Thirty-eight patients were enrolled (19/group). After 6 months, median sodium intake declined from 2137 to 1398 mg/d in the low-sodium and from 2678 to 1461 mg/d in the moderate-sodium diet group. Median BNP levels in the low-sodium diet group declined (216-71 pg/mL, P = .006), whereas in the moderate-sodium diet group, there was no change in BNP (171-188 pg/mL, P = .7; P = .17 between groups). For 6 months, median KCCQ clinical score increased in both groups (63-75 [P = .006] in the low-sodium diet group and 66-73 [P = .07] in the moderate-sodium group; P = .4 between groups). At 6 months, a post hoc analysis based on the dietary sodium intake achieved (> or ≤ 1,500 mg/d) in all patients showed an association between a sodium intake ≤ 1,500 mg/d and improvement in BNP levels and KCCQ scores. A dietary intervention restricting sodium intake was feasible, and achievement of this sodium goal was associated with lower BNP levels and improved quality of life in patients with HF.