Adult life course determinants of cardiac structure and function in the Medical Research Council 1946 birth cohort

Abstract

Background: Elevated blood pressure (BP) and body mass index (BMI) are associated with abnormalities of cardiac structure and dysfunction in cross-sectional studies. However the consequence of elevated BP and BMI over the adult life course on cardiac structure and function is unknown. Methods: Participants in the Medical Research Council National Survey of Health and Development (MRC NSHD) 1946 birth cohort (n=1653) underwent investigations including echocardiography and BP and BMI measurement at age 60-64y. BP had been measured previously at ages 36, 43 and 53y and BMI had previously been measured at ages 20, 26, 36, 43 and 53y. The relationships between BP, treatment for hypertension (HTT) and BMI and echocardiographic determinants of cardiac structure and function at age 60-64y were investigated. Results: Increased BP from age 36y onwards was associated with increased left ventricular mass index (LVMI) and poorer diastolic function (E/e’). This was independent of BP at age 60-64y for BP measured at age 53y. Faster rises of BP across mid-life were associated with greater increases in LVMI and E/e’. HTT was associated with increased LVMI and E/e’ after adjustment for BP at age 60-64y. Associations with systolic function were inconsistent. Increased BMI and overweight from the age of 20y onwards was associated with increased LVMI and poorer diastolic function. On including BMI/overweight at ages 60-64y, the associations remained for some ages (e.g. for ages 26y and 43y for LVMI and from age 36y onwards for E/e’). Earlier age at first detection of overweight was associated with increased LVMI and diastolic dysfunction. Associations with systolic function were inconsistent. Conclusions: Increased adult life course BP and BMI are associated with increased LVMI and diastolic dysfunction. Increased rate of change in BP is associated with detrimental effects to cardiac structure and function as is HTT. Earlier age of first detection of overweight is associated with increased LVMI and diastolic dysfunction. Earlier interventions to prevent rapid rises in BP and the development of obesity may be key in preventing future abnormalities in cardiac structure and function.