Job strain, long work hours, and suicidal ideation in US workers: a longitudinal study.

PURPOSE: To investigate whether chronic psychosocial work stressors (low job control, high job demands, job strain, low supervisor and coworker support, job insecurity, and long work hours) are longitudinally associated with suicidal ideation in a working population.
METHODS: Five-hundred seventy-eight workers (aged 34-69) were chosen for this analysis from those who participated in both project 1 (2004-2006 at baseline) and project 4 (2004-2009 at follow-up) of the Midlife Development in the United States II study. The median time interval between the two projects was 26 months (range 2-62 months).
RESULTS: About 11% of the workers reported suicidal ideation at follow-up, while 3% of them reported moderate/severe suicidal ideation at follow-up. After controlling for age, marital status, race, family history of suicide, and suicidal ideation at baseline, low skill discretion and job strain (a combination of low job control and high job demands) were associated with total suicidal ideation. After excluding those with suicidal ideation at baseline from analysis and further controlling for other work stressors, job strain was strongly associated with moderate/severe suicidal ideation: ORs, 4.29 (1.30-14.15) for quartile-based job strain and 3.77 (1.21-11.70) for median-based job strain. Long work hours (> 40 h/week vs. ≤ 40 h/week) also increased the likelihood for moderate/severe suicidal ideation: OR 4.06 (1.08-15.19).
CONCLUSIONS: Job strain and long work hours were longitudinally associated with moderate/severe suicidal ideation. Increasing job control and ensuring optimal level of work demands, including 40 h or less of work per week may be an important strategy for the prevention of suicide in working populations.