Table 5

Multivariate analysis of 3-year progression of log (mTSS) by disease activity and treatment at 1 year

Fixed effects model	Pooled estimates after multiple imputation (m=5 / N=496)
	Univariate analysis		Multivariate analysis
	β-Coef. (SD)	t Test p value	β-Coef. (SD)	t Test p value	Global F test p value
Details of continuous variables
Intercept	–	–	0.858 (0.19)	<0.001	<0.001
Age at baseline (years)	0.145 (0.04)	<0.001	0.090 (0.04)	0.025	0.005
Details of categorical variables
Presence of erosion at baseline					<0.001
No	Ref.	–	Ref.	–
Yes	0.551 (0.10)	<0.001	0.433 (0.10)	<0.001
SDAI
At 1 year					<0.001
Remission	Ref.	–	Ref.	–
LDA	0.609 (0.14)	<0.001	0.427 (0.13)	0.002
MDA or HDA	0.682 (0.13)	<0.001	0.518 (0.15)	<0.001
At 2 years					0.096
Remission	Ref.	–	Ref.	–
LDA	0.529 (0.12)	<0.001	0.244 (0.12)	0.046
MDA or HDA	0.275 (0.12)	0.024	0.055 (0.13)	0.671
ACPA presence					<0.001
Absence	Ref.	–	Ref.	–
Low titre	0.365 (0.18)	0.042	0.489 (0.17)	0.004
High titre	0.589 (0.10)	<0.001	0.497 (0.10)	<0.001
Biological DMARDs at 6 months					0.010
Absence	Ref.	–	Ref.	–
Presence	–0.616 (0.32)	0.055	–1.073 (0.32)	0.001
Biological DMARDs at 2 years					0.059
Absence	Ref.	–	Ref.	–
Presence	0.254 (0.15)	0.081	0.338 (0.15)	0.025
Glucocorticoids at 18 months					0.009
Absence	Ref.	–	Ref.	–
Presence	0.005 (0.10)	0.962	–0.275 (0.10)	0.005
DMARDs presence
At baseline					0.124
Absence	Ref.	–	Ref.	–
Presence	0.250 (0.19)	0.161	0.245 (0.16)	0.132
At 6 months					0.753
Absence	Ref.	–	Ref.	–
Presence	0.177 (0.13)	0.181	–0.127 (0.17)	0.465
At 1 year					0.425
Absence	Ref.	–	Ref.	–
Presence	0.243 (0.13)	0.062	0.019 (0.21)	0.928
At 18 months					0.331
Absence	Ref.	–	Ref.	–
Presence	0.293 (0.14)	0.030	0.145 (0.22)	0.519
At 2 years					0.834
Absence	Ref.	–	Ref.	–
Presence	0.312 (0.13)	0.001	–0.033 (0.27)	0.902
At 36 months					0.686
Absence	Ref.	–	Ref.	–
Presence	0.371 (0.13)	0.003	0.084 (0.21)	0.685
Random effects	σ coef.		σ coef.
Between-centre variability (σ_c)	–		0.173
Residual variability (σ)	–		0.916

ACPA, anticitrullinated peptides antibodies; no, low and high titres of ACPA by anti-CCP2 antibodies definition was <50 U/mL, 50–150 U/mL and >150 U/mL, respectively; DMARDs, disease-modifying antirheumatic drugs; HDA, high disease activity; LDA, low disease activity; log (mTSS), log of modified Sharp–van der Heijde total score; MDA, moderate disease activity; SDAI, Simple Disease Activity Index. p<0.05 values are shown in bold.