The Contribution of Four Immunogenetic Markers for Predicting Persistent Activity in Patients with Recent-Onset Rheumatoid Arthritis or Undifferentiated Arthritis

Table 4

Univariate and multivariate linear analyses to identify predictors for disease activity score (DAS28) at one year.

Variables^a	Univariate β coeff. (95% CI)	𝑃 value (Student’s 𝑡)	Multivariate β coeff. (95% CI)^b	𝑃 value (Student’s 𝑡)^b
Anti-CCP (neg. versus pos.)	0.57 (0.20, 0.93)	0.003	—	—
RF (neg. versus pos.)	0.56 (0.18, 0.93)	0.004	—	—
SE (−/− versus −/+)	0.74 (0.36, 1.03)	<0.001	0.67 (0.32, 1.01)	<0.001
SE (−/− versus +/+)	0.83 (0.15, 1.51)	0.017	0.73 (0.11, 1.35)	0.021
–308 TNFα (GA/AA versus GG)	0.01 (−0.46, 0.86)	0.980	—	—
Classification criteria (UA versus RA)	−0.29 (−0.31, 0.89)	0.342	—	—
Number of DMARD	0.66 (0.46, 0.86)	<0.001	0.63 (0.43, 0.82)	<0.001
Corticosteroids (yes versus. no)	−0.56 (−1.24, 0.15)	0.125	—	—
Linear regression equation
DAS28 at 1 year = 2.24 + 0.67 SE(−/+) + 0.73 SE(+/+) + 0.63 number of DMARDs
𝑅^2=0.225; 𝐹=20.373; 𝑃<0.001.

^a All variables measured at baseline, except classification criteria and treatments.
^b Values not shown for variables not included in the model, that is, those with 𝑃 values ≥0.15.
Abbreviations: CI: confidence interval. Anti-CCP: anticyclic citrullinated peptide antibodies. RF: rheumatoid factor. SE: shared epitope. −308 TNFα: G-to-A polymorphism at position 308 of the TNFα gene promoter. UA: undifferentiated arthritis. RA: rheumatoid arthritis. DMARD: disease-modifying antirheumatic drugs.