Patient demographics and baseline characteristics
| Referral strategy 1 (N=504) | Referral strategy 2 (N=568) | |
|---|---|---|
| Gender, n (%) | ||
| Male | 237 (47.0) | 310 (54.6) |
| Female | 267 (53.0) | 258 (45.4) |
| Age, years | 36.5±9.93 | 37.6±11.73 |
| Race, n (%) | ||
| White | 469 (93.1) | 511 (90.0) |
| Asian | 29 (5.8) | 44 (7.7) |
| Other | 6 (1.2) | 9 (1.6) |
| Not available | 0 (0) | 4 (0.7) |
| ESR, mm/h | 14.8±14.45 (n=418) | 16.4±17.74 (n=496) |
| Range | 1.0–80.0 | 0.0–110.0 |
| CRP, mg/l | 8.7±15.96 (n=409) | 8.5±15.36 (n=477) |
| Range | 0.0–150.0 | 0.0–120.0 |
| BASMI | 2.3±1.37 (n=342) | 2.5±1.50 (n=364) |
| BASFI | 3.4±2.24 (n=341) | 3.4±2.25 (n=362) |
| BASDAI | 4.5±2.12 (n=342) | 4.4±2.02 (n=365) |
| Other SpA manifestations, n (%) | 203 (40.3) | 275 (48.4) |
| Enthesitis | 78 (15.5) | 103 (18.1) |
| Peripheral asymmetric oligoarthritis | 69 (13.7) | 85 (15.0) |
| Family history positive for SpA | 60 (11.9) | 93 (16.4) |
| Anterior uveitis/iridocyclitis | 36 (7.1) | 37 (6.5) |
| Psoriasis | 30 (6.0) | 43 (7.6) |
| Inflammatory bowel disease | 14 (2.8) | 12 (2.1) |
| Dactylitis | 4 (0.8) | 17 (3.0) |
| HLA-B27, %* | 41.3 (n=361) | 35.0 (n=400) |
| Sacroiliitis on imaging, %* | 31.9 (n=461) | 34.2 (n=526) |
| IBP, %* | 82.0 (n=478) | 85.0 (n=514) |
*Collected by rheumatologists.
All data presented as mean±SD unless otherwise noted.
BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; BASFI, Bath Ankylosing Spondylitis Functional Index; BASMI, Bath Ankylosing Spondylitis Metrology Index; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; HLA, human leucocyte antigen; IBP, inflammatory back pain; SpA, spondyloarthritis.