A Cross-sectional Study on Factors Associated with Poor Work Outcomes in Patients with Axial Spondyloarthritis in Singapore

Aim: Axial spondyloarthritis (axSpA) affects patients in the prime of their economic productivity. We aim to identify factors associated with poor work productivity in patients with axSpA in Singapore.

Methods: A cross-sectional study was performed in two tertiary centers in Singapore. Consecutive adult patients ≥21 years fulfilling Assessment in Spondyloarthritis International Society (ASAS) 2009 criteria for axSpA were recruited. Data on social demographics, clinical, treatment modalities and patient-reported outcome measures (PROMs) were collected. Work productivity was assessed by the Work Productivity and Activity Impairment scale (WPAI:SpA). Factors associated with presenteeism, absenteeism, work productivity loss and activity impairment were evaluated.

Results: A total of 156 patients with axSpA were included: 72.4% employed, 80.1% male, 86.5% Chinese, median (Q1:Q3) age and duration of illness 36.7 (28.7:47.9) years, and 6.3 (1.6:12.2) years respectively. The mean (SD) activity impairment was 28.2% (24.3%). Among employed patients, mean (SD) absenteeism, presenteeism and work productivity loss was 4.5% (13.7%), 24.9% (19.9%) and 27.6% (23.2%), respectively. In multivariable analysis, absenteeism was associated with disease duration (P = .02) and EuroQol-5D (EQ-5D) (P = .04). Presenteeism was associated with Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) ≥4 (P = .04), Bath Ankylosing Spondylitis Functional Index (BASFI) (P < .01) and EQ-5D (P = .02). Work productivity loss was associated with BASFI (P = .02) and EQ-5D (P < .01). Activity impairment was associated with age (P = .04), BASDAI ≥ 4 (P < .01), BASFI (P < .01), EQ-5D (P < .01).

Conclusion: Active disease, reduced physical function and poorer quality of life are associated with reduced work productivity in patients with axSpA in Singapore. Addressing these factors can potentially improve work productivity in patients with axSpA.