The association between level of job control and suicide and suicide attempt in middle aged men

Introduction
The aim of this study was to investigate the association between low job control at age 40 and suicide and suicide attempt among Swedish men 40-56 years of age.

Methods
The study is based on a cohort of 40 035 Swedish males, born 1949-51, with data on job control attributed from occupational titles collected from censusus information in 1990 (at ages 39-41). For the study we have used information on unfavourable social and behavioural factors collected at compulsory conscription for military training in 1969/70 (at 18-20 years of age), information on achieved education and civil status at ages 39-41, and follow up data on suicide (164 cases) and suicide attempts (298 cases) between the years 1991-2006.

Results
An increased relative risk of suicide (OR=2.14 CI95%= 1.34-3.40) and of suicide attempts (OR=3.79 CI95%= 2.63-5.47) were found among workers in the lowest job control quartile compared with those in the highest quartile. In multivariate analyses, adjusting for social and behavioural factors measured at age 18-20 (heavy alcohol consumption, psychiatric diagnoses, social misbehaviour) the increased relative risk in low control jobs was reduced with 18% (suicide) and 23% (suicide attempts). After also adjusting for achieved education, income, and marital status in middle age a significantly increased relative risk of suicide attempt remained in the low control category (OR=2.48 CI95%= 1.62-3.79). The risk of suicide in the low control category was reduced with 79% and were no longer significantly increased.

Discussion
Low job control was associated with an increased risk of suicide attempt. The results suggest that the association between low job control, measured as in this study, and suicide and suicide attempt is confounded by other risk factors accumulated over the life-course.