Prevalence of daytime sleeping in the working population from estimates of nocturnal work shift

Abstract

Background: Sunlight has been linked the circadian rhythms that regulate sleep. Few studies have attempted to provide estimates on the size of the "daytime sleeper" population. Specific aims: Estimate prevalence of daytime sleepers in the labor force population and identify which demographic characteristics are risk factors for daytime sleeping. Methods: Cross-sectional, community-dwelling, nationally representative, observational study used information on 6,405,063 labor force participants representing 132,682,344 individuals in the contiguous United States. Data from the American Community Survey (ACS), Public Use Microdata Sample (PUMS), 2009-2013 (5-year) file was used to identify daytime sleepers (i.e., those who arrived at work between 7:00 PM and 2:59 AM). Findings: While nighttime sleepers represented 65.9% (n = 87,426,814) of those in the labor force population, daytime sleepers represent 3.3% (n = 4,344,311). Race-ethnic minority status, being disabled, and having low levels of educational attainment were found to be risk factors for daytime sleeping. Conclusions: Even though relatively small, the objectively large (≈ 4.3 million) number of daytime sleepers requires sleep research to invest resources in understanding how health varies in this population relative to those who primarily sleep in the absence of sunlight.