Comorbidities do not mitigate the effect of habitual physical activity on the reduction of healthcare costs among adults with cardiovascular diseases: A mediation analysis

Background: Habitual Physical activity (HPA) is a non-pharmacological strategy to prevent and control chronic diseases, and it plays an important role in minimizing healthcare costs. Objectives: This study aimed to investigate the relationship between HPA and healthcare costs from the perspective of the Brazilian National Healthcare System, and to establish the mediating role of comorbidities in this relationship among patients with cardiovascular diseases (CVD). Design and setting: This longitudinal study was conducted in a medium-sized Brazilian city and included 278 participants assisted by the Brazilian National Healthcare System. Methods: Information on healthcare costs were obtained from medical records and included primary, secondary, and tertiary levels. Comorbidities (diabetes, dyslipidemia, and arterial hypertension) were self-reported, and obesity was confirmed with the percentage of body fat. HPA was measured using a questionnaire (Baecke questionnaire). Face-to-face interviews provided information on sex, age, and education level. Statistical analysis included linear regression and Structural Equation Modeling, significance was set at 5 % and the Stata software (version 16.0) was used to perform the analysis. Results: The sample included 278 adults with a mean age of 54.49 (8.32) years. For each score of HPA, there was a reduction in healthcare costs of US$ 83.99/24 months (95 % CI: − 159.15; − 8.84), and the sum of comorbidities did not mediate this relationship. Conclusion: It is concluded that healthcare costs seem to be affected by HPA among patients with CVD, while this phenomenon seems not to be mediated by the sum of comorbidities.