COMPOSITIONAL ASSOCIATIONS OF SLEEP AND ACTIVITIES WITHIN THE 24-H CYCLE WITH CARDIOMETABOLIC HEALTH MARKERS IN ADULTS

Purpose To examine how compositions of 24-hour time-use, and time reallocations between movement behaviors, are associated with cardiometabolic health in a population-based sample of middle-aged Finnish adults. Methods Participants were 3,443 adults aged 46 years from the Northern Finland Birth Cohort 1966 study. Participants wore a hip-worn accelerometer for 14 days from which time spent in sedentary behavior (SB), light (LPA), and moderate-to-vigorous physical activity (MVPA) were determined. These data were combined with self-reported sleep to obtain the 24-hour time-use composition. Cardiometabolic outcomes included adiposity markers, blood lipid levels, and markers of glucose control and insulin sensitivity. Multivariable-adjusted regression analysis, using a compositional data analysis approach based on isometric log-ratio transformation, was used to examine associations between movement behaviors with cardiometabolic outcomes. Results More daily time in MVPA and LPA, relative to other movement behaviors, were consistently favorably associated with all cardiometabolic outcomes. For example, relative to time spent in other behaviors, 30 min/day more MVPA and LPA were both associated with lower 2-hour post glucose load insulin level (-11.8% and -2.7%, respectively). Relative to other movement behaviors, more daily time in SB was adversely associated with adiposity measures, lipid levels and markers of insulin sensitivity, and more daily time asleep was adversely associated with adiposity measures, blood lipid, fasting plasma glucose and 2-hour insulin. For example, 60 min/day more SB and sleep relative to the remaining behaviors were both associated with higher 2-hour insulin (3.5% and 5.7%, respectively). Conclusions Altering daily movement behavior compositions to incorporate more MVPA at the expense of any other movement behavior, or more LPA at the expense of SB or sleep, could help to improve cardiometabolic health in mid-adulthood.