Delayed sleep phase disorder risk is associated with absenteeism and impaired functioning

Abstract Study objectives The absence of a screening questionnaire for delayed sleep phase disorder (DSPD) remains a barrier to its detection and subsequent clinical evaluation. We developed a questionnaire to screen for DSPD risk and assessed its impact on self-reported absenteeism and functioning in work/school, social, and family life. Design Cross-sectional, with 13,844 individuals responding to a survey through an Internet survey provider, from which 1315 completed surveys were obtained from eligible participants. Participants A total of 1315 individuals who self-identified as evening type (n = 979) or as non-evening type (n = 356). Measurements and results A total of 295 participants were at high risk for DSPD, which is 5.1% of the total eligible survey respondents and 22.4% of our final sample with completed surveys. Compared to those who were not at high risk for DSPD, those who were at high risk were more likely to report frequent absenteeism, frequent loss of productivity, disruption to work or school activities, disruption to social life or leisure activities, and disruption to family life or home responsibilities. Difficulty with daytime sleepiness was more common in those at high risk for DSPD than those who were not. Increased sleep deficit on nights before school or work was also associated with more frequent difficulties with daytime sleepiness; 15.4% of those with no sleep deficit reported always or usually having difficulties with daytime sleepiness compared to 55.7% of those with a sleep deficit of 3 hours or more. Conclusions DSPD risk is associated with increased absenteeism and impaired functioning in work/school, social, and family life.