Aerobic physical activity and chronic diseases in Austrian adults aged 65 years and older: a model-based population attributable fraction study.

Introduction: Physical activity (PA) plays an important role in maintaining health and preventing chronic diseases, particularly among older adults. This study aimed to estimate the proportions of four major chronic diseases that could potentially be avoided if all older adults in Austria engaged in sufficient aerobic PA. Methods: Data from the 3,995 participants of the representative Austrian Health Interview Survey 2019 (ATHIS) aged 65+ years was analysed. Sufficient aerobic PA (minimum of 150 minutes moderate aerobic PA per week) was assessed using the European Health Interview Survey Physical Activity Questionnaire (EHIS-PAQ). Self-reported myocardial infarction or related health issues, stroke or resulting health problems, diabetes mellitus, and cancer were investigated as outcomes. Observed and counterfactual risks were estimated using survey-weighted logistic regression models, adjusted for sex, age, education, income, smoking status, and daily portions of fruits or vegetables. Model-based population attributable fractions (PAFs) were calculated from these predictions. Results: The recommendations for aerobic PA were fulfilled by 29.6% of participants. Model-based PAFs indicated that up to 46.6% (95% confidence interval (CI): 21.0 to 67.5%) of strokes, 40.8% (95% CI: 15.5 to 62.1%) of myocardial infarctions, and 35.8% (95% CI: 23.8 to 47.4%) of diabetes mellitus cases could possibly have been prevented if all participants fulfilled the recommendations for aerobic PA. The PAF for cancers (21.3%; 95% CI: -1.6 to 42.7%) was not statistically significant. Conclusions: Insufficient aerobic PA may account for substantial proportions of several chronic diseases in older Austrians. Given the cross-sectional study design and the possibility of reverse causality, the estimates should be interpreted as hypothetical upper bounds. Nonetheless, they underscore the importance of aerobic PA for disease prevention in older adults.