Predictors of insomnia symptoms in police employees: a longitudinal investigation and comparison of personality and psychosocial work factors

Insomnia is a growing public health concern and a risk factor for reduced health, safety, and performance among workers. This study investigated and compared the predictive value of personality traits and psychosocial factors associated with symptoms of insomnia. The study followed a longitudinal design and included 206 Norwegian police employees (52% men). The predictors of insomnia symptoms were divided into the following groups in the multiple regression analyses: 1) demands, control, and support at work, 2) stress and overcommitment, and 3) the personality traits of the five-factor model. A fourth final model included significant predictors from the initial analyses. The results showed high stability in insomnia symptoms at baseline and follow-up six months later. Neuroticism was the strongest and most stable predictor of insomnia, and associated with an increase in insomnia symptoms after six months. Overcommitment and stress had positive associations with insomnia symptoms but could not predict changes after six months. Social support had a negative association with insomnia, whereas job demands and control at work had no significant association with insomnia symptoms measured at follow-up six months later. The findings demonstrate that the personality trait neuroticism can play an important role in the development and maintenance of insomnia symptoms. Job demands and resources only explained a marginal proportion of variance in insomnia symptoms measured six months later in police employees, indicating that they may be less crucial in the development of insomnia. However, more research on the potential interaction effects between personality and organizational factors is needed. The study highlights the importance of taking personality characteristics into consideration when investigating predictors of insomnia.