Association between Obstructive Sleep Apnea and Left Ventricular Structure by Age and Gender: the Multi-Ethnic Study of Atherosclerosis

Abstract

Study objectives: The presence and severity of obstructive sleep apnea (OSA) are associated with impaired left ventricular (LV) structure and function. Our goal was to quantify the associations between LV systolic function and mass with severity of OSA in an ethnically diverse cohort, assessing variations by age and sex.

Methods: We conducted a cross-sectional analysis of data from 1,412 racially/ethnically diverse participants across 6 US communities from the Multi-Ethnic Study of Atherosclerosis who underwent both overnight polysomnography and cardiac magnetic resonance imaging from 2010-2012. We evaluated the association between the obstructive apnea-hypopnea index (AHI) by clinical category (< 5, 5-15, 15-30, 30-50, > 50) and secondary measures of sleep apnea with the outcomes left ventricular (LV) mass adjusted for height, LV mass/volume ratio, and LV ejection fraction.

Results: After adjusting for potential confounders and mediators, LV mass was significantly increased with increasing AHI category for subjects age 65 y or younger (β = 1.84 ± 0.47 g/m, P = 0.0001). The association between the AHI and LV mass appeared stronger in whites and Chinese compared to blacks and Hispanics, although interaction terms were not statistically significant. Additionally, while both LV mass and LV mass/volume ratio were significantly associated with hypoxia, ejection fraction was not associated with any OSA severity index. Comparable associations were observed in men and women.

Conclusions: Independent of confounders, higher levels of AHI are significantly associated with increased LV mass in both men and women younger than 65 y from a community-based cohort.

Keywords: cardiac magnetic resonance imaging; left ventricular mass; left ventricular mass/volume ratio; obstructive sleep apnea.

Figure 1

Left ventricular (LV) mass/height versus obstructive sleep apnea severity by age groups. This figure demonstrates a significantly steeper rise in LV mass/height with increasing apnea-hypopnea index (AHI) category in those age 65 y or younger, depicted by the blue line, compared to those older than 65 y as depicted by the red line (P interaction = 0.006). Dotted lines represent 95% confidence intervals.

Figure 2

Left ventricular (LV) mass/height versus obstructive sleep apnea severity by race. This figure demonstrate a tendency toward a steeper rise in LV mass/height with increasing apnea-hypopnea index (AHI) category (P interaction = 0.13) in whites (blue line) and Chinese (red line) compared to blacks (green line) and Hispanics (brown line). Dotted lines represent 95% confidence intervals.