Table 4

Cox proportional hazards regression models for drug discontinuation

Variable	Reference	Bivariate			Multivariate
Variable	Reference	HR	95% CI	P value	HR	95% CI	P value
All diseases
JAKi	TNFi	1.06	0.98 to 1.14	0.15	0.85	0.78 to 0.92	<0.001
Disease
Psoriatic arthritis	Rheumatoid arthritis	0.98	0.91 to 1.05	0.61	1.07	0.98 to 0.95	0.14
Axial spondyloarthritis	Rheumatoid arthritis	0.80	0.74 to 0.86	<0.001	0.84	0.76 to 0.95	0.003
Concomitant csDMARDs	Monotherapy	0.96	0.90 to 1.02	0.18	0.90	0.84 to 0.96	0.001
Disease duration		1.00	1.00 to 1.00	0.48	0.99	0.99 to 1.00	<0.001
Age at the start of treatment		1.00	1.00 to 1.01	0.002	1.00	1.00 to 1.00	0.57
GCs	No GCs	1.18	1.11 to 1.26	<0.001	1.13	1.05 to 1.21	<0.001
Charlson Comorbidity Index		1.09	1.06 to 1.12	<0.001	1.07	1.03 to 1.11	0.001
Sex, female	Male	1.23	1.16 to 1.31	<0.001	1.16	1.08 to 1.24	<0.001
Lines of treatment	First
Second		1.22	1.13 to 1.32	<0.001	1.30	1.20 to 1.40	<0.001
Third or higher		1.41	1.31 to 1.51	<0.001	1.53	1.41 to 1.65	<0.001
Disease activity (baseline)	Low
Medium		1.19	1.11 to 1.28	<0.001	1.19	1.10 to 1.28	<0.001
High		1.23	1.14 to 1.33	<0.001	1.34	1.23 to 1.46	<0.001
Rheumatoid arthritis
JAKi	TNFi	0.96	0.88 to 1.05	0.36	0.80	0.72 to 0.87	<0.001
Concomitant csDMARDs	Monotherapy	0.88	0.80 to 0.96	0.004	0.92	0.83 to 1.01	0.072
Disease duration		1.00	1.00 to 1.01	0.55	0.99	0.99 to 1.00	0.001
Age at the start of treatment		1.00	1.0 to 1.00	0.61	1.00	1.00 to 1.00	0.65
GCs	No GCs	1.17	1.07 to 1.27	<0.001	1.15	1.05 to 1.25	0.002
Charlson Comorbidity Index		1.08	1.03 to 1.13	0.002	1.07	1.01 to 1.12	0.014
Sex, female	Male	1.01	0.91 to 1.12	0.90	1.01	0.90 to 1.12	0.92
Lines of treatment	First
Second		1.26	1.13 to 1.41	<0.001	1.37	1.22 to 1.53	<0.001
Third or higher		1.57	1.43 to 1.73	<0.001	1.80	1.62 to 2.0	<0.001
Disease activity (baseline)	Low
Medium		1.15	1.04 to 1.27	0.006	1.19	1.08 to 1.32	0.001
High		1.36	1.20 to 1.53	<0.001	1.34	1.18 to 1.52	<0.001
Psoriatic arthritis
JAKi	TNFi	1.30	1.05 to 1.59	0.013	1.04	0.84 to 1.30	0.70
Concomitant csDMARDs	Monotherapy	0.87	0.77 to 0.97	0.014	0.90	0.08 to 1.02	0.10
Disease duration		0.99	0.99 to 1.00	0.10	0.99	0.98 to 1.00	0.004
Age at the start of treatment		1.00	1.00 to 1.01	0.16	1.00	1.00 to 1.01	0.17
GCs	No GCs	1.14	1.01 to 1.30	0.037	1.12	0.98 to 1.28	0.089
Charlson Comorbidity Index		1.01	0.94 to 1.09	0.82	1.00	0.92 to 1.08	0.94
Sex, female	Male	1.44	1.28 to 1.62	<0.001	1.36	1.20 to 1.54	<0.001
Lines of treatment	First
Second		1.23	1.06 to 1.41	0.005	1.26	1.09 to 1.46	0.002
Third or higher		1.31	1.14 to 1.50	<0.001	1.35	1.15 to 1.59	<0.001
Disease activity (baseline)	Low
Medium		1.22	1.06 to 1.40	0.005	1.23	1.07 to 1.42	0.004
High		1.40	1.20 to 1.64	<0.001	1.36	1.16 to 1.60	<0.001
Axial spondyloarthritis
JAKi	TNFi	0.62	0.34 to 1.13	0.12	0.58	0.32 to 1.06	0.079
Concomitant csDMARDs	No csDMARDs	0.86	0.73 to 1.02	0.075	0.85	0.71 to 1.01	0.059
Disease duration		1.00	0.99 to 1.01	0.73	1.00	0.99 to 1.00	0.19
Age at the start of treatment		1.00	1.00 to 1.01	0.12	1.00	1.00 to 1.01	0.45
GCs	No GCs	0.91	0.72 to 1.13	0.38	0.94	0.74 to 1.19	0.59
Charlson Comorbidity Index		1.13	1.06 to 1.21	<0.001	1.12	1.05 to 1.21	0.001
Sex, female	Male	1.21	1.06 to 1.38	0.005	1.20	1.04 to 1.37	0.01
Lines of treatment	First
Second		1.15	0.99 to 1.35	0.074	1.19	1.01 to 1.40	0.033
Third or higher		1.13	0.97 to 1.32	0.11	1.17	0.99 to 1.39	0.059
Disease activity (baseline)	Low
Medium		1.08	0.87 to 1.34	0.45	1.11	0.90 to 1.32	0.34
High		1.25	1.06 to 1.47	0.008	1.26	1.07 to 1.49	0.007

csDMARD, conventional synthetic DMARD; GC, glucocorticoid; JAKi, Janus kinase inhibitor; TNFi, tumour necrosis factor inhibitor.