Paid care work and depression: a longitudinal study of antidepressant treatment in female eldercare workers before and after entering their profession.

BACKGROUND: Previous studies have reported that employees in paid care work (e.g., child, health, and elderly care) have increased rates of hospitalization with depression and treatment with antidepressants. It is unclear, however, whether these findings reflect a causal effect of the work on employee mental health or a selection into these professions.
METHODS: We examined prevalences of antidepressant purchases during 1995-2008 in a cohort of female eldercare workers who entered their profession in 2004 (n = 1,946). These yearly prevalences were compared to those of a representative sample of the female Danish working population (n = 4,201). Trends in antidepressants prevalences were examined using generalized estimation equations. Further, to account for bias by treatment seeking, we compared self-reported depressive symptoms in 2005 measured by the mental health scale from the SF-36.
RESULTS: Female eldercare workers had consistently higher prevalence of antidepressant treatment than the general female working population. The eldercare workers were also more likely to suffer from depressive symptoms in 2005 (standardized prevalence ratio = 1.28, 95% CI = 1.09-1.49). Prevalences of antidepressant treatment increased during follow up for both cohorts, with similar estimated odds ratios of about 1.15 per year. The trend in the antidepressant prevalences for the eldercare workers was unchanged by entering eldercare work.
CONCLUSIONS: These findings indicate that female eldercare workers are at increased risk of depression. Further, as the trend in the antidepressant prevalences among the eldercare workers was similar before and after entering their profession, the results suggest that this increased risk is due to selection into the profession.