Abstract TH974: Left Ventricular Mass Index Changes across 20 Years of Follow-up Among Pre-Menopausal Women: The National Growth and Health Study

Abstract

Introduction: Left ventricular mass index (LVMI) is a known risk factor for cardiovascular (CV) disease. However, little is known about changes in LVMI across the lifespan, especially in relation to reproductive history. Hypothesis: We hypothesized that LVMI would increase over time, particularly among women with higher parity or higher CV risk factors in young adulthood. Methods: Participants from the National Growth and Health Study were assessed for LVMI, body composition by DEXA, anthropometry, lab values and blood pressure in young adulthood and midlife using consistent protocols. LVM was assessed by echocardiography and indexed to height 2.7 . Fat free mass index (FFMI, kg/m 2 ) was calculated as FFM divided by height (m) 2 . Systolic and diastolic blood pressures (SBP and DBP) were measured seated using an automated device. Spearman correlations, paired t-tests and general linear models were used in analysis. Results: In 161 women (53% Black), LVMI was assessed at baseline at a mean age of 25.5 ± 1.6 years and at follow up at a mean age of 46.2 ± 0.9 years. Over the 20 year period, LVMI increased by a mean (±SE) of 3.6 ± 0.8 g/m 2.7 and FFMI decreased by a mean of -0.76 ± 0.16 kg/m 2 (both p<0.0001). Baseline LVMI was significantly higher with greater parity at baseline (range 0-6), adjusting for FFMI (p=0.002), but follow-up LVMI was not associated with total parity (range 0-8; p=0.87; Table). Change in LVMI across 20 years were significantly correlated with baseline measures of LVMI (-0.39, p<0.0001), glucose (0.19, p=0.049) and parity at baseline (-0.17, p=0.03), but not baseline lipids, BP or FFMI. Changes in LVMI were also significantly correlated with differences in age (0.20, p=0.009) and FFMI over time (0.40, p<0.0001) and with current measures of DBP (0.17, p=0.04), insulin (0.24, p=0.003), high sensitivity CRP (0.26, p=0.001), HDL-C (-0.19, p=0.02), and total parity at follow-up (-0.18, p=0.03). In adjusted models, increases in LVMI were independently associated with increases in FFMI (p<0.0001), greater current DBP (p=0.01) and lower total parity (p=0.004). Conclusions: Greater increases in LVMI over 20 years of follow-up were seen among women with lower parity but not baseline CV risk factors. However, this negative association is likely due to higher initial LVMI and FFMI among women with greater parity by baseline age 25. Women with early parity should be evaluated for increases in LVMI, which may increase CV risk across the lifespan.