Shift work disorder in a random population sample--prevalence and comorbidities.
Few studies have investigated the presence of shift work disorder (SWD) in the general community. We addressed many of the limitations in this literature and present new findings. SWD has been treated as an 'all or none' construct but we propose the need to consider the 'severity' of the disorder. Using random digit dialling, we randomly recruited 1163 participants. Participants completed an extensive battery of scales and questions concerning work, health and individual differences. Three questions based on the criteria from the International Classification for Sleep Disorders were used to categorise participants with SWD (n = 176). In addition, we asked participants whether SWD interfered with aspects of their life and high ratings were used to define severe shift work disorder (SSWD). The prevalence of SWD was 32.1% among night workers and 10.1% in day workers (p<.001). SSWD was present in 9.1% of night workers and 1.3% of day workers (p<.001). Adjusted logistic regression analyses found significant associations between SWD and night work (OR = 3.35, CI 2.19-5.12), weekly work hours (OR = 1.02, CI 1.00-1.04), short sleep (≤ 6 h; OR = 2.93, CI 1.94-4.41), languidity (OR = 1.11, CI 1.06-1.16) and resilience (OR = 0.56, CI 0.43-0.81). Night work, short sleep, languidity, and hypertension were significantly associated with SSWD. Overall, participants with SSWD slept 0.80 h less than other participants (p<.001). Night work, short sleep and languidity were associated with both SWD and SSWD. Day workers with SWD symptoms reported significantly shorter sleep duration, higher levels of languidity and worked longer working hours compared to day workers without SWD.
School of Management and the Institute for Health and Social Science Research, Central Queensland University, Rockhampton, Queensland, Australia. v.dimilia@cqu.edu.au
Lee
L
Di Milia
Siri
S
Waage
Ståle
S
Pallesen
Bjørn
B
Bjorvatn
D000328:Adult; D015897:Comorbidity; D005260:Female; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011159:Population Surveillance; D015995:Prevalence; D020178:Sleep Disorders, Circadian Rhythm / Q000453:epidemiology*; D011795:Surveys and Questionnaires