Assessment of work disability in seronegative spondyloarthritis

Seronegative spondyloarthropathy (SpA) such as ankylosing spondylitis (AS) affects patients during their working years and may contribute to work disability (WD). We determined the prevalence of WD (not working due to illness) and limitations in work productivity in AS using surveys, including the Work Limitations Questionnaire (WLQ).

This cross sectional study consisted of 203 patients with SpA received a mailed questionnaire asking about work status, the WLQ, HAQ, BASDAI, BASFI, BAS-G and Functional Comorbidity Index. Relationships between WD, WLQ, demograghics and disease activity were assessed through bivariate correlations and independent t-tests.

Response rate was 40%; 64% had AS; 18.5% were work disabled. Those with WD were significantly older than non-WD, and had significantly higher scores on BASFI, BAS-G and patient global assessment of health. WD also had significantly more comorbid diseases than non-WD. WD prevalence was not associated with current longer duration of disease, higher HAQ scores or higher BASDAI scores. Using the WLQ, the average decrease in work productivity attributable to health was 8.3%. Decreases in time management (37.3%), physical demands (28.5%), mental-interpersonal demands (23.0%) and output (33.1%) were noted. Reduced productivity was not associated with demographic factors. Productivity loss for those still working was highly correlated (r>0.6) with the HAQ, BASFI, BASDAI, and BAS-G. Subjects with primary AS had less WD than those with other SpA (related to psoriasis, inflammatory bowel disease or reactive arthritis). WD was associated with older age and, HAQ scores and self-reported function on the BASFI. Losses in work productivity in those still working were highly correlated with the HAQ, BASFI, BASDAI and BAS-G. AS had less work disability than other SpA. Adjusting for gender, age, and duration of diseased did not affect the results.

WD occurred in 18.5% of SpA, and work productivity (in those working) was reduced by 8.3%. WD was associated with older age and greater SpA disease activity. Losses in work productivity were highly correlated with currently used clinical outcome measures such as HAQ, BASFI, BASDAI and BAS-G.