Cross-sectional relationships of circadian misalignment and rest-activity rhythms with occupational attainment in UK Biobank participants

Circadian misalignment and disrupted rest-activity rhythms have been linked to adverse health and educational outcomes, yet few studies have considered their relationships with economic outcomes. We investigate associations between multiple accelerometer-measured circadian misalignment traits (Composite Phase Deviation and the Sleep Regularity Index) and rest-activity rhythm traits (Inter-daily Stability, Intra-daily variability and relative amplitude), with occupational attainment, measured using the average wage paid to an individual's occupation. We use data from 20 356 UK Biobank participants who wore an accelerometer (2013-16), provided employment data for the year they wore the accelerometer, and supplied covariate data at recruitment (2006-10). We use linear regression, with incremental adjustments for four sets of covariates, and stratify our analysis by sex. Our findings provide mixed evidence on the relationship between circadian misalignment and occupational attainment, varying by the measure of circadian misalignment used, and sex. We find fragmented rest-activity rhythms to be associated with higher occupational attainment, which is counterintuitive. Since circadian misalignment is a modifiable trait, our results suggest potential benefits of policies aimed at reducing circadian misalignment, such as altering work schedules and reducing bright light exposure in the evening. Further research is needed to elucidate the mechanisms through which rest-activity rhythms may impact economic outcomes.