Background: Physical activity and appetite are important for maintaining physical health. Yet, sedentary lifestyle and poor appetite are frequently observed in the heart failure (HF) population. However, the relationships between these phenomena are not yet clearly understood. 

Purpose: To investigate the relationship between physical activity and appetite in patients with stable HF.

Methods: In this cross sectional study, a consecutive sample of 186 patients with confirmed HF with NYHA class II-IV (median age 72y, 70% men, NYHA class II 61%) participated in the study. Patients were recruited from three HF outpatient clinics in central Sweden. Physical activity measures included total energy expenditure (TEE), active energy expenditure (AEE) above 3 METs, average daily METs and number of steps per day during four days using a validated multi-sensor wearable armband (SenseWear®, Body Monitoring System). Patients also self-reported their physical activity on a ten point numeric rating scale, from extremely low (1) to extremely high (10). Self-reported appetite was measured by Council on Nutrition Appetite Questionnaire (CNAQ), an 8-item instrument (score range 8-40) where CNAQ ≤28 indicate poor appetite. Associations between physical activity and appetite were analyzed by Spearman correlation while differences in physical activity between poor vs good appetite were analyzed using Mann Whitney U test.

Results: There was a significant positive relationship between physical activity and appetite assessed by TEE (r_s=.184, p=.012), AEE of moderate intensity >3 METs (r_s=.262, p=.000), number of steps (r_s=.292, p=.000), average METs intensity (r_s=.249, p=.001), and self- reported physical activity (r_s=.191, p =.009). Levels of physical activity in the low appetite group differed significantly from the group with better appetite, this was seen in all physical dimensions, TEE (U=3225, z=-2.26, p=.024), AEE (U=2902, z=-3.178, p=.001), number of steps (U=2706, z=-3.734, p=.000), average METs intensity (U=3128, z=-2.541, p=.011), levels of self-reported physical activity (U=3185, z=-2.47, p=.013).

Conclusion: This study shows that physical activity is associated with appetite and that levels of physical activity differs between patients with poor and good appetite. These findings has implications for both research and practice and underlines the importance in monitoring both physical activity and appetite. Further research is needed to determine whether interventions targeting physical activity also improve appetite and vice versa in the HF population.