Objectives
We investigated the relationship of body mass index (BMI) and its 25-year change to left ventricular (LV) structure and function.
Background
Longstanding obesity may be associated with clinical cardiac dysfunction and heart failure. Whether obesity relates to cardiac dysfunction during young adulthood and middle age has not been investigated.
Methods
The Coronary Artery Risk Development in Young Adults (CARDIA) enrolled white and black adults aged 18-30 years in 1985-86 (Year-0). At the Year-25, cardiac function was assessed by conventional echocardiography, tissue Doppler imaging (TDI), and speckle tracking echocardiography (STE). Twenty-five year change in BMI (classified as Low:<27 Kg/m2 and High:≥27 Kg/m2) was categorized into four groups (Low-Low, High-Low, Low-High, and High-High). Multiple linear regression was used to quantify the association between categorical changes in BMI (Low-Low as reference) with LV structural and functional parameters obtained in middle age, adjusting for baseline and 25-year change in risk factors.
Results
The mean BMI was 24.4 kg/m2 in 3,265 participants included at Year-0. Change in BMI adjusted for risk factors was directly associated with incipient myocardial systolic dysfunction assessed by STE (High-High:β-coefficient=0.67; Low-High:β-coefficient=0.35 for longitudinal peak-systolic strain) and diastolic dysfunction assessed by TDI (High-High:β-coefficient=-074; Low-High:β-coefficient=-0.45 for e′) and STE (High-High:β-coefficient= -0.06 for circumferential early-diastolic strain rate). Greater BMI was also significantly associated with increased LV mass/height (High-High:β-coefficient=26.11; Low-High:β-coefficient=11.87).
Conclusions
Longstanding obesity from young adulthood to middle age is associated with impaired LV systolic and diastolic function assessed by conventional echocardiography, TDI, and STE in a large bi-racial cohort of adults aged 43-55 years.