Association of hostility with sleep duration and sleep disturbances in an employee population

"Background: Sleep disturbances are common among the general population, and hostile persons have been proposed to be at greater. risk of several serious health problems and diseases. Purpose: This study examined the relationships between hostility, sleep disturbances, and sleep duration in a large non-clinical sample of 5,433 employees working in 12 Finnish hospitals. Method: Data were collected by questionnaire surveys in 1998 and 2000. Results: Higher hostility was cross-sectionally associated with increased sleep disturbances but not with sleep duration after adjustment for gender; age, marital status, education, shift work, smoking, alcohol consumption, physical activity, body mass index, psychiatric morbidity, and somatic disease. A stratified analysis distinguishing individuals with stable hostility across the two measurements and those with transient hostility (> 0.5 SD difference between measurements) replicated the association with increased sleep disturbance in both groups, but among those with transient hostility, there additionally was a cross-sectional association between higher hostility and shorter sleep duration. Conclusion: Our evidence suggests that hostility is an independent risk factor-for sleep disturbances and that transient hostility may also predispose shorter sleep duration. However, the effect sizes for all these associations were small, suggesting limited clinical significance for our findings."