Effects of Nutrition Therapy in Heart Failure: a Systematic Review and Meta-Analysis

This systematic review aimed to assess the effects of nutritional therapy on the clinical outcomes and exercise capacity of patients with HF.

Protocol for this systematic review was registered with PROSPERO (CRD42023467011). We conducted a systematic review according to the PRISMA guidelines. The CENTRAL and MEDLINE databases were systematically searched for relevant articles published on March 31, 2023. Randomized controlled trials (RCTs) reporting the effects of nutritional therapy on exercise capacity and clinical outcomes in out- and inpatients with HF were included. Two researchers independently performed the screening, selection, data extraction, and bias risk assessment using the Cochrane Risk of Bias Tool ver. 1. Review Manager 5.4 was used for the meta-analysis, with the pooled risk ratio (RR) and mean difference (MD) estimated using a random-effects model with 95% confidence interval (CI). A subgroup analysis was conducted if high heterogeneity (I² >50%) was observed.

We included 20 RCT with 1,876 patients. Regarding the 6-min walk test outcomes, four out of seven studies showed a high bias risk in the blinding of participants and personnel, and two studies had incomplete outcome data. Nutrition therapy did not reduce all-cause mortality (RR; 0.79, 95% CI; 0.54–1.15, I²=38%, p=0.22) or rehospitalization (RR; 0.93, 95% CI; 0.48–1.81, I²=12%, p=0.84), whereas it decreased the risk of cardiovascular events (RR 0.64; 95% CI 0.48–0.85, I²=0%, p0.01). There was no significant improvement in exercise capacity with nutrition therapy (peak oxygen uptake; MD 0.36 mL/kg/min, 95% CI; -0.83–1.54, I²=53%, p=0.55, 6-min walk test; MD 10.91 m, 95% CI; -8.93–30.75, I²=68%, p=0.28). Subgroup analysis showed significant improvements in exercise capacity in multicenter studies (peak oxygen uptake; MD 1.90 mL/kg/min, 95% CI; 0.05–3.75, p=0.04, 6-min walk test; MD 95.00 m, 95% CI 2.69–187.31, p=0.04), but not in single-center studies.

Meta-analysis indicated that nutrition therapy for out- and inpatients with HF reduces the risk of cardiovascular events. However, its effect on exercise capacity improvement remains unclear.

Nutritional therapy improves clinical outcomes in patients with HF. Further high-quality multicenter RCTs are needed to clarify their effects on exercise capacity. Future research should explore the combined effects of nutritional and exercise therapy.