Occupational distress in a group of nurses: the moderator role of insomnia

Objectives: The Job Strain theory proposed by Karasek and Theorell (1990) suggests that health risks are greater among people who experience high job demands (e.g., time pressure), coupled with low control (e.g., decision authority) over how their work is conducted. Demanding jobs, accompanied with low decision latitude, have been associated with various physical and psychological stress related disorders. The present cross sectional study examined in a group of nurses the possible moderator role of insomnia in the relationship between job strain (High Demands/Low Control) and emotional exhaustion and somatic complaints. Methods.: Participants were 215 nurses (female = 84%; mean age: 44.8 ± 7.4); Predictor Variables were: 1. Measures of the occupation demands and control specific for the nursing profession (Leiden Quality of Work Life Questionaire for Nurses, Maes. et al., 1999). 2. Impact of the insomnia evaluated through the Sleep Disorder Questionnaire (Violani, et al., 2004), a brief questionnaire which evaluates the presence of insomnia according to DSM-IV criteria and its impact based on the number of daytime consequences. Criterion Variables were: 1. Emotional Exhaustion measured through the Maslach Burnout Inventory (Maslach et al., 1996). 2. Somatic complaints measured through a scale from the Symptom Checklist (Derogatis, 1983). Results: Results show that both levels of demands and insomnia are positively correlated with emotional exhaustion beta = 0.21; P < 0.05; beta = 0.33; P < 0.005), and with somatic complaints (beta;=0.39; P < 0.000; beta = 0.30; P < 0.005). For both criterion variables the three way interaction is significant, explaining respectively 4%; P < 0.01 and 6%; P < 0.009 of the variance. In both cases, the Slopes analyses show that the condition characterized by high demands-low control and insomnia was more detrimental for the well being of participants than the other conditions. The final model explained 45% of variance in the case of emotional exhaustion (F7,83 = 9.73; P < 0.001) and 37% of variance in the case of somatic complaints (F(7,88)= 6.69; P < 0.001). Conclusion: Insomnia seems to act as exacerbator of the effects of perceived job strain on psychological distress (emotional exhaustion and somatic complaints). These findings suggest to include sleep hygiene workshop in stress management programs for nurses.