Threefold analysis of the individual effects of physical activity, processing speed, and aging on structural and functional cardiac variables: from the aging imageomics study

Abstract

Background: Aging constitutes a significant risk factor for cardiovascular diseases, which stand as the leading cause of mortality in Spain. Prior studies have underscored the positive impact of physical activity on lifespan extension and the mitigation of cardiovascular risk factors. However, limited research has explored its influence on cardiac structural and functional alterations. Additionally, while dementia has been associated with cardiac changes, the relationship between processing speed and cardiac parameters within a healthy population remains relatively unexplored. Aging is a complex process, and in itself, it has been associated with various structural and functional cardiac changes, some of which ultimately contribute to an increased cardiovascular risk. Objectives: to analyze the individual effects of physical activity, processing speed, and aging on structural and functional cardiac variables. Methods: Cardiac structure and function parameters were assessed using cardiovascular magnetic resonance (CMR). The study included a sample of 746 participants of both sexes, with an average age of 66.85 years. Physical activity levels were quantified using the International Physical Activity Questionaire (IPAQ), processing speed was evaluated with the Symbol Digit Test, and aging was recorded in years. Statistical analyses included t-tests, Welch test, and linear regression models for the entire sample, sex-stratified, and adjusted for age, sex and cardiovascular risk factors. Results: All cardiac variables were found to be significantly higher in males compared to females, except for the EndoGLS and GRS. In the analysis of physical activity, no statistically significant differences were observed in the left ventricle between ‘high’ and ‘moderate-low’ levels. The only exceptions were an increase of the LV EndoGCS in females (2.64%), and an increase of the LVCO in males (0.14 l/(min*m2)). When considering the right ventricle, the overall sample showed a significant increase in the RVEDV (p-value 0.001) and RVESV (p-value <0.001). Processing speed levels were not found to have any significant associations with cardiac structural and functional variables. When analyzing the impact of increasing age on cardiac structural and functional variables, several associations were found. Both sexes showed an increased LV M/V ratio (p-value <0.001), and a decrease in the RVEDV and RVSV. Moreover, males exhibited a significant reduction of the LVEDV (-0,27 ml/m2 each year of age) as well as a significant decrease of the LVSV, LVCO and RVESV. Conclusions: In a non-athletic community-based population, results suggested a general lack of association between physical activity levels and both structural and functional cardiac variables. Notably, the right ventricle volumes increased with higher activity levels. In contrast, processing speed had no impact on cardiac variables. Increasing age was associated with a decrease in several cardiac parameters. Both males and females had significant changes in LV M/V ratio, RVEDV, and RVSV. However, other variables differed between the sexes