An investigation of work disability and related factors in ankylosing spondylitis patients

Objective To study the characteristics of work disability and its influencing factors in patients with ankylosing spondylitis (AS). Methods The demographic data, work conditons and disease related characteristics of 277 patients with AS were recorded, and randomly selected from the Department of Rheumatology, Chinese PLA General Hospital from November 2014 to January 2016. Work and productivity activity impair-ment questionnaire (WPAI) was used to survey the work disability and productivity loss, then explore its in-fluencing factors and the relationships between patient-reported outcomes and WPAI scores. Logistic regression was used to analyze the associated factors of work disability. Multivariate linear regression was used to analyze the predictive factors of lose of work productivity. Results The prevalence of work disability was 30.3%. Twenty patients were unemployed because of working disability. Two hudreds patients were employed, with average 36.5(24.0, 50.0) hours workingtime in the past week. Average AS related absenteeism was 4.4(0, 10) hour. Average workproductivity loss was 26.4%(2.5%, 40.0%). Logistic multiple regression analysis showed that Bath AS disease activity index (BASDAI), SF-36 physical component summary(PCS) scores might be the important influencing factors among those clinical measures(OR=1.270, 0.959). Presenteeism and overall work impairment were moderately correlated with patients' global assessment of disease activity (VAS), BASDAI, bath AS functional index (BASFI), SF-36 physical Functioning (PF), SF-36 body pain (BP) and SF-36 Physical Component Summary (PCS) (| r|=0.539-0.648). Linear multivariate analyses indicated that work presente-eismand absenteeismwere significantly associated with BASDAI (P<0.01). Conclusion High prevalence of work disability in patients with AS is noted, which is closely related with disease activity and body function; High attention should be paid to AS patients with work disability. Key words: Spondylitis, ankylosing; Work capacity evaluation; Work and productivity activity impairment questionnaire