Comparing Sodium Intake Strategies in Heart Failure

In the past 2 decades, heart failure (HF) research has focused primarily on drugs and devices. In contrast, evidence remains scarce and mostly observational for dietary sodium restriction,1–3 arguably the most widely recommended self-care measure for patients with HF. In recent studies, patients with HF consumed an average of 3600 to 4200 mg sodium daily by 24-hour urinary sodium excretion,4 with 65% consuming >3000 mg.5 Although the evidence suggests that high-sodium intake worsens outcomes, the level of sodium intake that achieves optimal outcomes for patients with HF is unknown.6–12 All current guidelines emphasize sodium intake restriction; however, there is no consensus on the actual level. Recommendations are either nonspecific or ranging between 2000 and 3000 mg/d,9 largely based on opinions or observational studies. In explicit acknowledgment of the evidence gap, the recent European Society of Cardiology guidelines for HF12 have not assigned a level of evidence to sodium intake recommendations. The recent American College of Cardiology Foundation and American Heart Association guidelines recommend (class IIa) that sodium restriction is reasonable for patients with HF with congestive symptoms, but do not recommend a specific target level.13 The inconsistency of guidelines underlines the weak database that supports this cornerstone treatment. Current data indicate limited adherence with recommended sodium restriction among patients with HF. In a recent interventional study, when instructed to limit sodium intake to 2500 mg/d, patients with HF averaged a daily intake of 2700 to 3900 mg/d by 24-hour urinary sodium, depending on the assigned arm, after 8 months of intervention.4 Sodium intake reduction is difficult to adhere to even among patients with symptomatic HF, with less than one third of patients reporting sodium intake ≤2500 mg/d by 3-day food diaries, which underestimate actual sodium intake.4 Congruent …