Table 2. Effect of the presence of the shared epitope and the minor rs7574865 allele in STAT4 or rs2476601 in PTPN22 on disease activity (DAS28) and disability (HAQ) in patients with early arthritis.

	DAS28		HAQ
	β Coeff. (95% CI)	p value	β Coeff. (95% CI)	p value
Age (years):
<45	Ref.		Ref.
45–65	0.54 (0.31–0.78)	<0.001	0.06 (−0.01–0.14)	0.108
>65	0.71 (0.46–0.97)	<0.001	0.11 (0.02–0.19)	0.011
Gender
Man	Ref.		Ref.
Woman	0.48 (0.31–0.78)	<0.001	0.09 (0.02–0.17)	0.016
Diagnosis
RA	Ref.		Ref.
UA	−0.50 (−0.81– −0.20)	0.001	−0.10 (−0.19− −0.01)	0.023
Positive ACPA	0.21 (0.01–0.42)	0.049	NS	NS
DAS28	NI	NI	0.30 (0.28–0.31)	<0.001
Shared epitope	NS	NS	NS	NS
STAT4 (rs7574865)
GG	Ref.		Ref.
GT	−0.01 (−0.21–0.20)	0.953	0.07 (0.01–0.14)	0.055
TT	0.42 (0.01–0.83)	0.044	0.19 (0.05–0.32)	0.007
PTPN22 (rs2476601)
CC	Ref.		Ref.
CT	−0.27 (−0.56– −0.01)	0.042	NS	NS
TT	−0.68 (−1.64–0.27)	0.162	NS	NS
Hospital
Center 1	Ref.		Ref.
Center 2	−0.35 (−0.56– −0.13)	<0.001	NS	NS

DAS28, 28-joint Disease Activity Score; HAQ, Health Assessment Questionnaire; Coeff., coefficient; Ref., reference; RA, rheumatoid arthritis; UA, undifferentiated arthritis; ACPA, anti-citrullinated peptide antibodies; NI, not included; NS, non-significant.