Common mental disorders and disability pension award: seven year follow-up of the HUSK study.

OBJECTIVE

Rates of disability pension (DP) awards remain high in most developed countries. We aimed to estimate the impact of anxiety and depression on DPs awarded both for mental and for physical diagnoses and to estimate the relative contribution of sub case-level anxiety and depression compared with case-level symptom loads.

METHODS

Information from a large cohort study on mental and physical health in individuals aged 40-46 (N=15,288) was linked to a comprehensive national database of disability benefits. Case-level and sub case-level anxiety and depression were defined as scores on the Hospital Anxiety and Depression Scale of >or=8 and 5-7, respectively. The outcome was incident award of a DP (including ICD-10 diagnosis) during 1-7-year follow-up.

RESULTS

DP awards for all diagnoses were predicted both from case-level anxiety [HR 1.90 (95% CI 1.50-2.41)], case-level depression [HR 2.44 (95% CI 1.65-3.59] and comorbid anxiety and depression [HR 4.92 (95% CI 3.94-6.15)] at baseline. These effects were only partly accounted for by adjusting for baseline somatic symptoms and diagnoses. Anxiety and depression also predicted awards for physical diagnoses [HR 3.26 (95% CI 2.46-4.32)]. The population attributable fractions (PAF) of sub case-level anxiety and depression symptom loads were comparable to those from case-level symptom loads (PAF anxiety 0.07 versus 0.11, PAF depression 0.05 versus 0.06).

CONCLUSION

The long-term occupational impact of symptoms of anxiety and depression is currently being underestimated. Sub case-level symptom loads of anxiety and depression make an important and previously unmeasured contribution to DP awards.