Dietary Sodium Intake and Outcomes: a Secondary Analysis From Sodium-HF

Abstract

This post hoc analysis of SODIUM-HF (Study of Dietary Intervention under 100 mmol in Heart Failure) assessed the association between baseline dietary sodium intake and change at 6 months with a composite of cardiovascular (CV) hospitalizations, emergency department visits and all-cause death at 12 and 24 months. Dietary sodium restriction is common advice for patients with heart failure (HF). Randomized clinical trials have not shown a beneficial effect of dietary sodium restriction on clinical outcomes. A multivariable Cox proportional hazard regression model was used to assess the association of dietary sodium intake measured at randomization with primary and secondary endpoints. The study included 792 participants. Baseline sodium intake was ≤ 1500 mg/day in 19.9% (n = 158), 1501-3000 mg/day in 56.5% (n = 448) and > 3000 mg/day in 23.4% (n = 186) of participants. The factors associated with higher baseline sodium intake were higher calorie consumption, higher body mass index and recruitment from Canada. Multivariable analyses showed no association between baseline sodium intake nor magnitude of 6-month change or 12- or 24-month outcomes. In a responder analysis, participants achieving a sodium intake < 1500 mg at 6 months showed an association with a decreased risk for the composite outcome (adjusted HR 0.52 [95% CI 0.25, 1.07] P = 0.08) and CV hospitalization (adjusted HR 0.51 [95% CI 0.24, 1.09] P = 0.08) at 12 months. There was no association between dietary sodium intake and clinical outcomes over 24 months in patients with HF. Responder analyses suggest the need for further investigation of the effects of sodium reduction in those who achieve the targeted dietary sodium-reduction level.