Sex Differences in the Association of Cumulative Body Mass Index from Early Adulthood to Middle Age and Left Atrial Remodeling Evaluated by Three-Dimensional Echocardiography: The Coronary Artery Risk Development in Young Adults Study

Abstract

Background: The relationship between long-term obesity and left atrial (LA) structure and function is not entirely understood. We examined the association of cumulative body mass index (cBMI) with LA remodeling using three-dimensional (3D) speckle-tracking echocardiography (STE).

Methods: The Coronary Artery Risk Development in Young Adults (CARDIA) study is a community-based cohort of black and white, men and women, ages 18-30 years at baseline in 1985-86 from four U.S. centers. This study included 2,144 participants who had satisfactory image quality and body mass index measurements during the entire follow-up period. The 3D STE-derived LA parameters were maximum, minimum, and pretrial contraction volumes; total, passive, and active emptying fraction; maximum systolic longitudinal strain; and early and late diastolic longitudinal strain rates. Multivariable linear regression analyses stratified by sex assessed the relationship between cBMI and 3D STE-derived LA parameters, adjusting for demographics and traditional cardiovascular.

Results: The mean age of the cohort was 55 ± 3.6 years; 54.8% were women, and 46.5% were black. There were statistically significant additive sex interactions for the association between cBMI and LA minimum contraction value, maximum systolic longitudinal strain, and early and late diastolic longitudinal strain rates. In the fully adjusted model, greater cBMI was associated with lower magnitude LA longitudinal deformation (maximum systolic longitudinal strain and early and late diastolic longitudinal strain rates) in men and with higher LA emptying fraction in women. In addition, greater cBMI was associated with higher LA phasic volumes indices in both men and women.

Conclusions: This study showed that while greater cBMI from early adulthood throughout middle age was associated with higher LA volumes in both genders, differences were found for LA function, with lower longitudinal deformation in men and higher reservoir and active LA function in women.

Keywords: 3D echocardiography; Body mass index; Gender; Left atrium remodeling.

Figure 1

Study enrollment flow chart.

Figure 2

Multiplane display of the LA 3D full volume showing five plane views composed of three cross-section slices ([C7], [C5], and [C3]), and two longitudinal orthogonal planes (four-chamber [A] and two-chamber [B] views).

Figure 3

Three-dimensional speckle-tracking volume analysis (A, blue line), strain analysis (B, brown line), and strain rate analysis (C, green line).

Figure 4

Plots showing linear regression fits for men and women with the 3D echo variables on the y-axis and cumulative BMI on the x-axis. The shaded regions around the fitted value lines represent 95% CIs. BSA, Body surface area.