Midlife blood pressure change and left ventricular mass and remodelling in older age in the 1946 British Birth Cohort Study

Abstract

Aims: Antecedent blood pressure (BP) may contribute to cardiovascular disease (CVD) independent of current BP. Blood pressure is associated with left ventricular mass index (LVMI) which independently predicts CVD. We investigated the relationship between midlife BP from age 36 to 64 and LVMI at 60-64 years.

Methods and results: A total of 1653 participants in the British 1946 Birth Cohort underwent BP measurement and echocardiography aged 60-64. Blood pressure had previously been measured at 36, 43, and 53 years. We investigated associations between BP at each age and rate of change in systolic blood pressure (SBP) between 36-43, 43-53, and 53-60/64 years on LVMI at 60-64 years. Blood pressure from 36 years was positively associated with LVMI. Association with SBP at 53 years was independent of SBP at 60-64 years and other potential confounders (fully adjusted β at 53 years = 0.19 g/m(2); 95% CI: 0.11, 0.27; P < 0.001). Faster rates of increase in SBP from 43 to 53 years and 53 to 60/64 years were associated with increased LVMI. Similar relationships were seen for diastolic, pulse, and mean pressure. Rate of increase in SBP between 43-53 years was associated with largest change in LVMI (β at 43-53 years = 3.12 g/m(2); 95% CI: 1.53, 4.72; P < 0.001). People on antihypertensive medication (43 years onwards) had greater LVMI even after adjustment for current BP (β at 43 years = 12.36 g/m(2); 95% CI: 3.19, 21.53; P = 0.008).

Conclusion: Higher BP in midlife and rapid rise of SBP in 5th decade is associated with higher LVMI in later life, independent of current BP. People with treated hypertension have higher LVMI than untreated individuals, even accounting for their higher BP. Our findings emphasize importance of midlife BP as risk factor for future CVD.

Keywords: Blood pressure; Echocardiography; Left ventricular hypertrophy; Left ventricular mass.

Figure 1

(A) Predicted left ventricular mass index at 60–64 years by systolic blood pressure at 53 years (red) and by systolic blood pressure at 60–64 years (blue) plotted separately for men and women and by antihypertensive treatment status. Vertical lines represent mean systolic blood pressure in the National Survey of Health and Development sample; solid line for men and dashed line for women. (B) Predicted left ventricular mass index at 60–64 years by standard deviation change in systolic blood pressure between 43 and 53 years (magenta) and between 53 and 60–64 years (green) plotted separately for men (solid) and women (dashed), for individuals with an average conditional change in the other periods. Vertical lines represent mean systolic blood pressure change.