Mental fatigue, work and sleep.
OBJECTIVE
The study examined the multivariate relationship between mental fatigue and different work-related (work load, work hours) and background/life style factors, as well as disturbed sleep.


METHODS
A total of 5720 healthy employed men and women living in the greater Stockholm area participated in a questionnaire study on cardiovascular risk factors. The data were analysed using a multiple logistic regression analysis with self-rated fatigue as the dependent variable.


RESULTS
Fatigue was predicted by disturbed sleep (4.31; 3.50-5.45, high immersion in work (4.17; 2.93-5.94), high work demands (2.39; 1.54-3.69), social support, being a female, being a supervisor and high age. Shift work, work hours (including overtime) and influence at work did not become significant predictors. With control for work demands a high number of work hours was associated with lower fatigue.


CONCLUSIONS
Disturbed sleep is an important predictor of fatigue, apparently stronger than previously well-established predictors such as work load, female gender, lack of exercise, etc.
Akerstedt
T
T
National Institute for Psychosocial Factors and Health, Department of Public Health Sciences, Karolinska Institute, Stockholm, Sweden. torbjorn.akerstedt@ipm.ki.se
Knutsson
A
A
Westerholm
P
P
Theorell
T
T
Alfredsson
L
L
Kecklund
Göran
G
D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D005221:Fatigue / Q000523:psychology*; D005260:Female; D006801:Humans; D007587:Job Description; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010561:Personnel Staffing and Scheduling; D012307:Risk Factors; D012737:Sex Factors; D012893:Sleep Wake Disorders / Q000523:psychology*; D016526:Workload