Associations of Wearable Ring Measured Sleep, Sedentary Time, and Physical Activity With Cardiometabolic Health: A Compositional Data Analysis Approach.

Movement behaviors within the 24-h day, including physical activity (PA), sedentary time, and sleep, are associated with cardiometabolic health. We aimed to determine the association between 24-h movement composition and cardiometabolic health while accounting for sleep efficiency. Altogether, 1134 participants from the Northern Finland Birth Cohort 1986 study, free from prior cardiovascular disease, provided at least 4 days of 24-h activity and sleep efficiency measured with a wearable ring. Participants' body composition was assessed with bioimpedance, blood pressure, and waist circumference were measured, and lipids and glucose were analyzed from a fasting blood sample. Linear regression models for cardiometabolic outcomes were created with 24-h movement composition and covariates, including sleep efficiency and behavioral and socioeconomic factors. Isotemporal time reallocations were used to demonstrate the dose-dependent associations between time use and outcomes. Beneficial associations with the outcomes were detected when sedentary time was reallocated to light PA, moderate-to-vigorous PA (MVPA), or sleep. For example, substituting 30 min of sedentary time with MVPA was associated with 7.2% (95% CI from -9.8% to -4.5%) lower visceral fat area, 4.9% (95% CI from -6.5% to -3.3%) lower body fat percentage, 1.6% (95% CI from -2.3% to -0.9%) smaller waist circumference, and 2.4% (95% CI from 1.2% to 3.5%) higher high-density lipoprotein (HDL) cholesterol after accounting for gender, marital status, education level, employment, smoking, alcohol consumption, and sleep efficiency. Substituting sedentary time with sleep or light PA showed beneficial but smaller differences in adiposity measures and HDL cholesterol. Limiting sedentary time should be encouraged in adulthood.