Baseline characteristics of the BSRBR-AS population.
| Characteristics | Working, n = 1188 | Not Working, n = 733 |
|---|---|---|
| Age, yrs ** | 43.7 (34.6–52.3) | 62.2 (48.1–68.3) |
| Age at rheumatology referral, yrs** | 33 (26–42) | 41 (29–52) |
| Sex, male* | 767 (65) | 529 (72) |
| Classification criteria** | ||
| Modified New York criteria | 635 (53) | 237 (32) |
| ASAS imaging | 475 (40) | 383 (52) |
| ASAS clinical | 78 (7) | 113 (15) |
| HLA-B27 status** | ||
| Positive | 684 (83) | 337 (75) |
| Negative | 145 (17) | 115 (25) |
| Job type | ||
| Sedentary | 715 (55) | – |
| Labor-intensive | 592 (45) | – |
| Absenteeism, % | 0 (0–0) | – |
| Presenteeism, % | 30 (10–50) | – |
| Overall work impairment, % | 30 (10–53) | – |
| Activity impairment (%)** | 30 (10–60) | 60 (30–80) |
| Logistic Regression† | ||
| Likelihood of working** | OR | 95% CI |
| BASDAI (scored: 0 best–10 worst) | 0.74 | 0.70–0.79 |
| BASFI (scored: 0 best–10 worst) | 0.70 | 0.66–0.73 |
| BASMI (scored: 0 best–10 worst) | 0.69 | 0.64–0.75 |
| ASQoL (scored: 0 best–18 poorest) | 0.84 | 0.81–0.86 |
Values are n (%) or median (IQR) unless otherwise indicated.
↵* Statistically significant difference between work and not working of p < 0.05.
↵** Statistically significant difference between work and not working of p < 0.01.
↵† Adjusted for age, sex, and deprivation. BSRBR-AS: British Society for Rheumatology Biologics Register in Ankylosing Spondylitis; ASAS: Assessment of Spondyloarthritis international Society; BASDAI: Bath Ankylosing Spondylitis Disease Activity Index; BASFI: Bath AS Functional Index; BASMI: Bath AS Metrology Index; ASQoL: Ankylosing Spondylitis Quality of Life questionnaire; IQR: interquartile range.