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

Knudsen, Ann Kristin; Øverland, Simon; Aakvaag, Helene Flood; Harvey, Samuel B.; Hotopf, Matthew; Mykletun, Arnstein

doi:10.1016/j.jpsychores.2010.03.007

« Previous Next »Journal of Psychosomatic Research
Volume 69, Issue 1 , Pages 59-67, July 2010

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

Ann Kristin Knudsen
- Research Section of Mental Health Epidemiology, Department of Health Promotion and Development, Faculty of Psychology, University of Bergen, Bergen, Norway
- Corresponding author. Research Section of Mental Health Epidemiology, Department of Health Promotion and Development, Faculty of Psychology, University of Bergen, Bergen, Norway Christiesgt. 13, N-5020 Bergen, Norway. Tel.: +47 55 58 83 55; fax: +47 55 58 98 87.
Simon Øverland
- Research Section of Mental Health Epidemiology, Department of Health Promotion and Development, Faculty of Psychology, University of Bergen, Bergen, Norway
Helene Flood Aakvaag
- Research Section of Mental Health Epidemiology, Department of Health Promotion and Development, Faculty of Psychology, University of Bergen, Bergen, Norway
Samuel B. Harvey
- Kings College London, Institute of Psychiatry, London, UK
Matthew Hotopf
- Kings College London, Institute of Psychiatry, London, UK
Arnstein Mykletun
- Research Section of Mental Health Epidemiology, Department of Health Promotion and Development, Faculty of Psychology, University of Bergen, Bergen, Norway
- Norwegian Institute of Public Health, Division of Mental Health, Oslo, Norway

Received 6 September 2009; received in revised form 2 March 2010; accepted 9 March 2010. published online 05 May 2010.

Abstract

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 ≥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.

Abbreviations: CI, Confidence Intervals, DP, Disability pension, HADS, The Hospital Anxiety Depression Scale, HR, Hazard Ratio, HUSK, The Hordaland Health Study, ICD, International Classification of Diseases, OECD, Organisation for Economic Co-operation and Development, PAF, Population Attributable Fractions