Dietary Sodium Adherence Is Poor in Chronic Heart Failure Patients

Background: We sought to determine the rates and predictors of dietary sodium restriction and to evaluate the reliability of 24-hour urine collection as a tool to estimate dietary sodium intake in heart failure (HF) patients. Methods and Results: We evaluated the 24-hour urinary sodium excretion of 305 outpatients with HF and reduced ejection fraction who were educated on following a <2 g sodium diet. The mean sodium excretion according to a single sample from each participant was 3.15 +/- 1.58 g, and 23% were adherent to the <2 g recommendation. One hundred sixty-eight participants provided 2 samples with urinary creatinine excretion within normative range. Averaging both resulted in a mean sodium excretion of 3.21 +/- 1.20 g and lower adherence rates to the <2-gram diet: 14% versus 23% (P = .019). Multivariate logistic regression showed only male sex and higher body mass index (BMI) to be associated with nonadherence (male: odds ratio [OR] 2.20, 95% confidence interval [CI] 1.25-3.88; 1 unit BMI: OR 1.05, 95% CI 1.01-1.10). Bland-Altman plots of urinary sodium and creatinine showed poor reproducibility between samples. Conclusions: In this chronic I-IF population, sodium consumption probably exceeds recommended amounts, particularly in men and those with higher BMI. Urine analyses were not highly reproducible, suggesting variation in both diet and urine collection.