Table 4.

Cox regression analysis for predictors of TNFi discontinuation in patients with axial inflammatory arthritis. Values are HR (95% CI).

Variables	Final Model, Adjusted
Variables	Univariable	Baseline Variables Only	Baseline Variables and First-year BASDAI50 Response	Baseline Variables and First-year ASDAS-ID Response
Sex, male vs female	0.67 (0.52–0.87)^{^b}	0.74 (0.56–0.98)^{^a}	0.62 (0.40–0.95)^{^a}	0.66 (0.43–1.02)^*
Age, per 10 yrs	0.92 (0.73–1.17)
Symptom duration, < vs ≥ 5 years	1.40 (1.08–1.82)^{^a}
TNFi agent used, ETN vs other	1.94 (1.44–2.61)^{^c}	1.68 (1.24–2.28)^{^b}		1.88 (1.40–2.53)^{^a}
Clinical diagnosis
AS (ref)	1.00 (ref)
PsA	1.06 (0.76–1.48)
Other	1.52 (1.09–2.14)^{^a}
Year of TNFi therapy start, per 2 yrs	1.20 (1.10–1.31)^{^c}	1.13 (1.03–1.24)^{^a}
Previous csDMARD, yes vs no	0.84 (0.66–1.07)^**	0.68 (0.52–0.88)^{^b}	0.64 (0.42–0.96)^{^a}	0.71 (0.48–1.05)^*
MTX co-therapy, yes vs no	0.96 (0.73–1.25)
Peripheral disease, yes vs no	1.41 (1.08–1.84)^{^a}	1.47 (1.12–1.93)^{^b}
CRP, > vs ≤ 1.2 mg/dl	0.72 (0.54–0.96)^{^b}
VAS global, > vs ≤ 60	1.15 (0.88–1.53)
PGA, > vs ≤ 2	0.87 (0.64–1.19)
BASDAI, > vs ≤ 5	1.09 (0.81–1.48)
BASFI, > vs ≤ 5	1.15 (0.83–1.59)
BASDAI50, yes vs no	0.49 (0.34–0.72)^{^c}		0.49 (0.34–0.71)^{^c}
ASDAS-ID, yes vs no	0.33 (0.22–0.51)^{^c}			0.33 (0.26–0.41)^{^c}

↵* p < 0.1.
↵** p < 0.2.
↵a p < 0.05.
↵b p < 0.01.
↵c p < 0.001. TNFi: tumor necrosis factor inhibitor; BASDAI50: 50% improvement of Bath Ankylosing Spondylitis Disease Activity Index; ASDAS-ID: Ankylosing Spondylitis Disease Activity Score–Inactive Disease; ETN: etanercept; AS: ankylosing spondylitis; PsA: psoriatic arthritis; csDMARD: conventional synthetic disease-modifying antirheumatic drugs; MTX: methotrexate; CRP: C-reactive protein; VAS: visual analog scale; PGA: physician’s global assessment; BASFI: Bath Ankylosing Spondylitis Functional Index.