Three gram sodium intake is associated with longer event-free survival only in patients with advanced heart failure.

BACKGROUND

There is limited evidence to support the recommendation that patients with heart failure (HF) restrict sodium intake. The purpose of this study was to compare differences in cardiac event-free survival between patients with sodium intake above and below 3 g.

METHODS

A total of 302 patients with HF (67% male, 62 ± 12 years, 54% New York Heart Association [NYHA] Class III/IV, ejection fraction 34 ± 14%) collected a 24-hour urine sodium (UNa) to indicate sodium intake. Patients were divided into 2 groups using a 3-g UNa cutpoint and stratified by NYHA Class (I/II vs. III/IV). Event-free survival for 12 months was determined by patient or family interviews and medical record review. Differences in cardiac event-free survival were determined by Kaplan-Meier survival curve with log-rank test and Cox hazard regression.

RESULTS

The Cox regression hazard ratio for 24-hour UNa ≥ 3 g in NYHA Class I/II was 0.44 (95% confidence interval [CI] = 0.20-0.97) and 2.54 (95% CI = 1.10-5.84) for NYHA III/IV after controlling for age, gender, HF etiology, body mass index, ejection fraction, and total comorbidity score.

CONCLUSIONS

These data suggest that 3 g dietary sodium restriction may be most appropriate for patients in NYHA functional Classes III and IV.