0550 Insomnia is Associated with Greater Arterial Stiffness and Cardiac Dysfunction

Abstract

Introduction: Insomnia is a novel and modifiable risk factor for incident cardiovascular disease (CVD). However, identification of early markers of subclinical CVD in diagnosed insomnia is understudied. Our aim for this ongoing study is to contrast markers of cardiovascular structure and function between people with insomnia and good-sleeping controls. Methods: Persons with insomnia (met ICSD-III criteria) and good sleeping controls (<8 Insomnia Severity Index, mean 8-night SOL and WASO<31min) were recruited from the community. Twentytwo adults (21-39y; 55% women) with no history of CVD, diabetes, inflammatory conditions, significant hypertension, or current sleep-disordered breathing (WatchPat200, Itamar Medical) were enrolled and underwent fasting cardiovascular testing. Testing included: Central augmented aortic pressure (AP) and carotidfemoral pulse wave velocity (cfPWV) for vascular stiffness; brachial artery flow mediated dilation (FMD) to assess endothelial function; and 2D echocardiography to assess ejection fraction (EF%), left ventricular global longitudinal strain (LVGLS), left atrial volume index (LAVI), mitral valve E/e' ratio (E/e'), and lateral e'. ANCOVA models, adjusting for age, comparing persons with insomnia (n=6) to good sleeping controls (n=16) on each cardiovascular measure were conducted. Results: AP (range:-5,10mmHg), cfPWV (range: 4.8-7.6m/s), EF% (range:55.0-72.0%), LVGLS (range:-26,-19%) LAVI (range:14.1- 26.7mL/m2), E/e' (range:3.2-7.8), and lateral e' (range:0.09-0.22cm/ sec) were all within normal ranges according to age and sex normative standards. Mean FMD was 8.8% (SD=4.3, range:4.3-19.8%). Age adjusted ANCOVA models indicated that the insomnia group had significantly worse cardiovascular function than good sleeping controls on cfPWV (M=6.8±0.3 vs. M=5.7±0.2; p=0.004), EF% (M=60.0±1.7 vs. M=65.2±1.0; p=0.017), LVGLS (M=-21.6±0.6 vs. M=-24.3±0.4; p=0.001), and lateral e' (M=0.12±0.01 vs. M=0.18±0.01; p=0.003). No group differences were found for AP, FMD, LAVI, and E/e'. Conclusion: Among relatively healthy young adults, people with insomnia had greater arterial stiffness and worse left ventricular systolic and diastolic functioning.