Sleep parameters associated with cardiometabolic health in older women: a cross-sectional study.

BACKGROUND AND AIMS: Sleep health disturbances have been shown to increase the risk of cardiometabolic diseases. As women age, they experience elevated cardiometabolic risk. The purpose of this study was to examine i) if "good" and "poor" sleepers differed in cardiometabolic risk and ii) which sleep parameters were associated with cardiometabolic risk factors. METHODS AND RESULTS: Women aged 50+ with type 2 diabetes, pre-diabetes, or moderate-high risk for diabetes were recruited. Indices of sleep quantity and quality were measured using the Fitbit Inspire 2 worn continuously for 3-7 days. Good sleepers were categorized as having an average sleep duration of 7-9 h and sleep efficiency ≥80%. Poor sleepers did not meet these criteria. Homeostasis model assessment of insulin resistance (HOMA-IR), Metabolic Z-score (MetS), Cardiometabolic Risk Score and Framingham Risk Score were calculated from measured variables (e.g., blood pressure). All analyses used multiple linear regression adjusted for age, ethnicity, income, physical activity, diet quality, and alcohol consumption. 183 participants enrolled and 168 were included in the analyses. The average age of participants was 60 years (±6), and most were peri/postmenopausal (86%). Differences in cardiometabolic risk factors between good and poor sleepers were not statically different (p > 0.05). Greater sleep duration variability (β = 0.043, 95% Confidence Interval [CI] = 0.02, 0.07; p < 0.001) and wake time variability (β = 0.028, 95% CI = 0.01, 0.05; p = 0.007) were significantly associated with elevated cardiometabolic risk scores. CONCLUSION: Sleep variability is associated with cardiometabolic risk among older women. Improving sleep consistency may promote cardiometabolic health. TRIAL REGISTRATION: The parent trial is registered with clinicaltrials.gov: NCT05454943.