Abstract 33: Parity is Associated with Aortic Remodeling: The Multi-Ethnic Study of Atherosclerosis (MESA)
Introduction: Several lines of evidence suggest that increased gravidity and/or parity is associated with increased risk for clinical cardiovascular events and left ventricular remodeling. However, the mechanism(s) that account for these associations remain unclear. Recent analyses from MESA indicate that parity is also associated with increased carotid stiffness; consistent with the hypothesis that extra-cellular matrix remodeling that occurs to facilitate child birth may also lead to adverse effects on arterial structure and function. To date there are few data on the effects of gravidity or parity on central aortic structure and function. To study this we examined the relationship between reproductive history and MRI-based measures of aortic dimensions in women enrolled MESA.
Methods: Study subjects included 1908 women aged 45-84, from four race/ethnic groups who were free from cardiovascular disease. Women were classified as having 0 to ≥ 5 live births and 0 to ≥6 pregnancies. Minimum and maximum cross-sectional area and average diameter of the descending aorta at the level of the right pulmonary artery were measured using thoracic MRI. After exploratory data analysis and data cleaning, univariate and multivariable models were used to describe the relationship between number of pregnancies or live births and aortic dimensions, after adjustment for potential confounders including age, race-ethnicity, height, weight, smoking, diabetes, total and HDL cholesterol, SBP, use of anti-hypertensive medications and education as a proxy for socio-economic status.
Results: Of 1908 participants, 41.1% were Caucasian, 31.1% African-American, 16.7% Hispanic and 11.1% Chinese-American. The mean (±SD) age was 61.1±10.0 years, 46% had HTN, and 19% had diabetes mellitus or impaired fasting glucose. In univariate analyses, minimum and maximum aortic area were 14 mm2 larger and average diameter was 0.28 mm greater for each live birth (all p<0.001). In fully adjusted models the number of live births remained significantly associated with min and max area and average diameter (all p<0.005). Qualitatively similar results were seen using number of pregnancies.
Conclusions: Increasing number of pregnancies and live births is associated with greater aortic remodeling. Further studies are needed to determine if specific physiologic effects of pregnancy are responsible for the apparent deleterious consequences on arterial remodeling and whether these changes translate into adverse cardiovascular outcomes.
Author Disclosures: S.R. Aggarwal: None. D.A. Bluemke: None. W.G. Hundley: None. J.A. Lima: None. M.A. Mittleman: None. P. Ouyang: None. N.I. Parikh: None. D. Vaidya: None. J. Yeboah: None. D.M. Herrington: None.
- © 2014 by American Heart Association, Inc.