Moderate Physical Activity in Healthy Adults Is Associated With Cardiac Remodeling.

Timothy J.W Dawes,Ben Corden,Roddy Walsh,Declan P O’Regan,Stuart A Cook,Antonio De Marvao,Sorcha Cotter,James S Ware

doi:10.1161/circimaging.116.004712

Abstract

Cardiac mass and volumes are often elevated in athletes, but it is not known whether moderate physical activity is also associated with cardiac dilatation and hypertrophy in a healthy adult population. In total, 1096 adults (54% female, median age 39 years) without cardiovascular disease or cardiomyopathy-associated genetic variants underwent cardiac magnetic resonance imaging to determine biventricular volumes and function. Physical activity was assessed using a validated activity questionnaire. The relationship between cardiac parameters and activity was assessed using multiple linear regression adjusting for age, sex, race, and systolic blood pressure. Logistic regression was performed to determine the effect of activity on the likelihood of subjects having cardiac dilatation or hypertrophy according to standard cardiac magnetic resonance normal ranges. Increasing physical activity was associated with greater left ventricular (LV) mass (β=0.23; P<0.0001) and elevated LV and right ventricular volumes (LV: β=0.26, P<0.0001; right ventricular: β=0.26, P<0.0001). Physical activity had a larger effect on cardiac parameters than systolic blood pressure (0.06≤β≤0.21) and a similar effect to age (-0.20≤β≤-0.31). Increasing physical activity was a risk factor for meeting imaging criteria for LV hypertrophy (adjusted odds ratio 2.1; P<0.0001), LV dilatation (adjusted odds ratio 2.2; P<0.0001), and right ventricular dilatation (adjusted odds ratio 2.2; P<0.0001). Exercise-related cardiac remodeling is not confined to athletes, and there is a risk of overdiagnosing cardiac dilatation or hypertrophy in a proportion of active, healthy adults.

Highlights

Cardiac mass and volumes are often elevated in athletes, but it is not known whether moderate physical activity is associated with cardiac dilatation and hypertrophy in a healthy adult population
Physical Activity In an average week, 8% of the cohort reported engaging in no regular exercise at all, 41% light activity, 35% moderate physical activity, and 16% >5 hours
In adults with no known comorbidities of cardiovascular disease and no genetic variants associated with cardiomyopathy, increasing physical activity is an independent predictor of elevated biventricular volumes and left ventricular (LV) mass

Summary

Methods

Circ Cardiovasc Imaging is available at http://circimaging.ahajournals.org. Heart Project (www.digital-heart.org) between March 2011 and January 2015. We excluded participants at screening who had known cardiovascular disease or were being treated for hypertension, diabetes mellitus, or hypercholesterolemia, or had a first degree relative with cardiomyopathy. All subjects were sequenced for disease-causing cardiomyopathy and channelopathy genes using a comprehensive sequencing assay,[8] and 62 individuals with putative pathogenic genetic variants were excluded.[9] Female subjects were excluded if they were pregnant or breastfeeding but were eligible if they took oral contraceptives. Standard published safety contraindications to magnetic resonance imaging were applied.[10] All subjects provided written informed consent for participation in the study, which was approved by a research ethics committee

Results

Discussion

Conclusion