Withdrawal from labour force due to work disability in patients with ankylosing spondylitis
- A Boonena,
- A Chorusb,
- H Miedemac,
- D van der Heijded,
- R Landewée,
- H Schoutenf,
- H van der Tempelg,
- S van der Lindena
- aDepartment of Internal Medicine, Division of Rheumatology, University Hospital Maastricht, The Netherlands, bDivision of Public Health, TNO Prevention and Health, Leiden, The Netherlands, cNetherlands Expert Centre for Work-related Musculoskeletal Disorders, University Hospital Dijkzigt and Erasmus University Rotterdam, The Netherlands, dDepartment of Internal Medicine, Division of Rheumatology, University Hospital Maastricht, The Netherlands and Limburg University Centre, Diepenbeek, Belgium, eDepartment of Internal Medicine, Division of Rheumatology, University Hospital Maastricht and Atrium Medical Centre, Heerlen, The Netherlands, fDepartment of Methodology and Statistics, University of Maastricht, The Netherlands, gMaasland Ziekenhuis, Sittard, The Netherlands
- Dr A Boonen, Department of Internal Medicine, Division of Rheumatology, University Hospital Maastricht, P O Box 5800, 6202 AZ Maastricht, The Netherlands
- Accepted 4 April 2001
OBJECTIVE To investigate withdrawal from the labour force because of inability to work owing to ankylosing spondylitis (AS) and to determine the characteristics of patients with no job because of work disability attributable to AS.
METHODS A postal questionnaire was sent to 709 patients with AS aged 16–60 years followed up by a rheumatologist. Kaplan-Meier survival statistics were used to assess the time lapse between diagnosis and withdrawal from work. Standardised incidence ratios were calculated to compare withdrawal from the labour force in patients with AS and the general population. Determinants of withdrawal were assessed by Cox's proportional hazard regression analysis using variables assumed to be time independent. Cross sectional characteristics of patients without a job owing to disability were further analysed by simple and multiple regression analyses.
RESULTS A total of 658 patients returned the questionnaire. Of 529 patients with a paid job before diagnosis of AS, 5% had left the labour force within the first year after the diagnosis, 13% after 5 years, 21% after 10 years, 23% after 15 years, and 31% after 20 years. Age and sex adjusted risk for withdrawal was 3.1 (95% CI 2.5 to 3.7) times higher than in the general population. In patients with AS, determinants of withdrawal from work were older age at diagnosis, manual work, and coping strategies characterised by limiting or adapting activities. Patients with work disability at the time of the study were older, came from a lower social class, and were more likely to have total hip replacement, peripheral arthritis, or comorbidity. Moreover, they reported worse physical function (BAS-FI), experienced lower quality of life, and more often had extraspinal disease than those with a job.
CONCLUSION Withdrawal from work is 3.1 times higher in patients with AS than expected in the general population. Within patients, higher age at diagnosis, manual work, and unfavourable coping strategies are important determinants of withdrawal. Patients without a job experience a lower quality of life.