What effects did the dietary interventions studied in Evangelista et al and Pritchett et al have on various parameters in patients with heart failure?
The dietary intervention study conducted by Evangelista et al randomized 14 symptomatic patients with HFrEF (NYHA class II III) with type 2 diabetes mellitus and BMI 27 kg/m2 to 12 weeks of a high-protein diet, standard-protein diet, or control. Patients in both intervention groups achieved weight loss, with greater decreases in waist circumference and percentage body fat seen with the high-protein diet. There was also a significant improvement in HF symptoms and QOL associated with weight loss. However, there was no change in cardiac structure or function. Pritchett et al studied 20 obese patients with HFrEF randomized for 3 months to standard therapy (control) versus lifestyle modification, including a portion-controlled diet with meal replacements and an unsupervised walking program. In this study, the intervention group did not have weight loss, and there was no significant difference between the intervention and control groups in terms of metabolic, biomarker, or functional parameters.