Unemployment and work disability due to common mental disorders among young adults: selection or causation?

Unemployment in early adulthood is associated with higher rate of disability due to common mental disorders (CMDs). We investigated to what extent the association between unemployment and sub-sequent long-term sickness absence due to CMDs is direct or whether it is dependent on accumulation of mental health problems and socioeconomic disadvantage.

In this longitudinal study, a population-based 60% sample of Finnish young adults born between 1983 and 1985 (N = 116 878) was followed up for the incidence of CMDs from 2006 to 2010. Sociodemographic and health-related covariates were identified using several nationwide registers. Hazard ratios (HRs) with 95% confidence intervals (CIs), and survival and cumulative hazard functions for CMD were calculated. A matching procedure was applied to account for the systematic differences in the distribution of the baseline characteristics.

A total of 1416 (2.4%) of men and 2539 (4.4%) of women were granted a long-term sickness allowance for CMD during the follow-up. After matching, HR (95% CI) of CMD for men decreased from 2.38 (2.12-2.68) to 1.31 (1.03-1.67) and for women from 1.97 (1.79-2.18) to 1.39 (1.18-1.65). Approximately half of the effect of the unemployment on CMDs was explained by the background variables.

Using a causal approach, our study suggests that unemployment is consistently associated with an increased risk of work disability due to CMDs. Considering the young unemployed as a risk group may help in targeting interventions promoting mental health and improving educational and employment opportunities.