Univariate Analyses | Final Multivariate Model, Backward Selection | |||
---|---|---|---|---|
HR (95% CI) | p | HR (95% CI) | p | |
Diagnosis | ||||
AS | 1 | < 0.0001 | — | — |
Nr-axSpA | 1.41 (1.20–1.67) | |||
Sex | ||||
Men | 1 | < 0.0001 | 1 | 0.002 |
Women | 1.72 (1.46–2.03) | 1.52 (1.16–1.97) | ||
Disease duration, yrs | 0.99 (0.98–0.99) | 0.02 | — | — |
Age | ||||
< 45 yrs | 0.91 (0.77–1.07) | 0.2 | 1.05 (0.83–1.33) | 0.6 |
≥ 45 yrs | 1 | 1 | ||
TNFi start year | ||||
2005–2008 | 0.58 (0.47–0.72) | < 0.0001 | — | — |
2009–2011 | 0.82 (0.67–1.01) | |||
2012–2014 | 1 | |||
HLA-B27+ | 1 | < 0.0001 | 1 | < 0.0001 |
HLA-B27–negative | 1.93 (1.61–2.32) | 2.15 (1.51–3.06) | ||
TNFi drug type | ||||
Adalimumab | 1 | 0.10 | ||
Etanercept | 1.01 (0.79–1.28) | — | — | |
Infliximab | 1.01 (0.82–1.23) | |||
Golimumab | 1.35 (1.05–1.73) | |||
Smoking | ||||
Current | 1.52 (1.25–1.86) | < 0.0001 | ||
Previous | 1.34 (1.04–1.72) | — | — | |
Never | 1 | |||
Baseline BASDAI, mm | 1.01 (1.01–1.02) | < 0.0001 | 1.01 (1.00–1.02) | 0.002 |
Baseline BASMI, mm | 0.99 (0.99–1.00) | 0.6 | — | — |
Baseline CRP | ||||
≤ 10 mg/l | 1.52 (1.26–1.84) | < 0.0001 | 1.36 (1.08–1.71) | 0.01 |
> 10 mg/l | 1 | 1 |
Similar results regarding effects of HLA-B27 and axSpA subdiagnosis were found when (1) applying multiple imputation of missing data; and (2) patients with nr-axSpA diagnosed according to the clinical arm were excluded. AS: ankylosing spondylitis; axSpA: axial spondyloarthritis; TNFi: tumor necrosis factor inhibitor; BASDAI: Bath Ankylosing Spondylitis Disease Activity Index; BASMI: Bath Ankylosing Spondylitis Metrology Index; CRP: C-reactive protein; nr-axSpA: nonradiographic axSpA.