Arcand et al. (2011)
Population size and characteristics Arcand et al. (2011) examined data from 123 New York Heart Association (NYHA)2 Class I/II and class III/IV medically stable CHF patients enrolled in multidisciplinary CHF programs in two tertiary care hospitals in Canada. Patients were between 18 and 85 years of age, had a left ventricular ejection fraction (LVEF) of <35 percent, were medically stable for at least 3 months, and were on standard medical therapy. Patients were excluded if they had significant renal dysfunction or cardiac cachexia. All patients were consuming a self-selected diet.
Study design, purpose, and length This small prospective cohort study followed participants for 3 years to determine whether a high sodium intake is related to acute decompensated heart failure (ADHF) in ambulatory patients.
Sodium intake measure and method Sodium intake was measured using two 3-day food records: at baseline and after 6-12 weeks. Intake estimates were verified by 24-hour urine analysis in a subset of patients.
Range of intake, reference, and adjustments Calorie-adjusted sodium intakes were pooled as tertiles with cut-points at 1,900 mg per day and 2,700 mg per day.
Outcome measure, confounders, and adjustments The primary outcome measure was ADHF. Secondary outcomes were all-cause hospitalization and death or transplantation. Adjustments were made for age, sex, energy intake, LVEF, beta blockers, furosemide, and BMI.
Direction and significance of effect High sodium intake levels (≥2,800 mg per day) were significantly associated with ADHF (HR=2.55 [CI: 1.61, 4.04] p=0.001), all-cause hospitalization (HR=1.39 [CI: 1.06, 1.83]), and mortality (HR=3.54 [CI: 1.46, 8.62] p=0.005).
2 The NYHA Functional Classification system is used to classify heart failure based on severity of symptoms and how the person feels during physical activity. Class I patients have cardiac disease but no limitation of physical activity. Class II patients experience slight limitations in physical activity (e.g., fatigue and palpitation). Patients classified as Class III experience limitation in less than ordinary physical activity. Class IV patients are unable to participate in physical activity without discomfort and may experience heart failure symptoms at rest (AHA, 2011).