Dietary Sodium Intake and Risk of Incident Heart Failure in the Southern Community Cohort Study

BACKGROUND: The association of dietary sodium intake with incident heart failure (HF) among individuals at high-risk for HF is not established. OBJECTIVES: The objective of the study was to assess the association between dietary sodium intake and incident HF risk. METHODS: We examined 25,306 Southern Community Cohort Study participants (median age 54 years, 63% female, 69% Black, 87% <$25k annual income) without prevalent HF and with Centers for Medicare and Medicaid Services coverage at enrollment (2002-2009). Dietary sodium intake at enrollment was assessed with a validated food frequency questionnaire. Incident HF was ascertained by Centers for Medicare and Medicaid Services claims through 2016. Cox modeling was performed with population-attributable fraction of dietary sodium on incident HF calculated. RESULTS: The mean dietary sodium intake was 4,269 ± 2,502 mg/day. Over 9.8 years median follow-up, 7,039 (27.8%) individuals developed HF. Each 1,000 mg/day greater sodium intake associated with an 8% (95% CI: 4%-11%) higher risk of incident HF, independent of sociodemographics, diet quality, calories, physical activity, and hyperlipidemia. Further adjustment for hypertension, body mass index, sleep, or coronary artery disease yielded similar results. The dietary sodium association with incident HF was similar among individuals with diabetes (HR: 1.08; 95% CI: 1.02-1.15). Population-attributable fraction analysis indicated reducing sodium intake to a maximum of 4,000 mg/day could eliminate 6.6% (95% CI: 3.6%-9.6%) of incident HF over 10 years. CONCLUSIONS: Among low-income Black and White adults in the southeast United States, greater dietary sodium intake associates with a higher risk of incident HF. Modest reduction in sodium consumption may significantly reduce the burden of HF in this high-risk population.