Serial determination of cyclic citrullinated peptide autoantibodies predicted five-year radiological outcomes in a prospective cohort of patients with early rheumatoid arthritis

Table 3 Correlation between worsening of radiographic Sharp score and mean serial anti-CCP2 concentration or baseline anti-CCP2 concentration

Sharp score	Mean anti-CCP2 concentration Δ(M0 + M12 + M36)/3		Anti-CCP2 concentration baseline (M0)
	r (95% CI)	Pa	r (95% CI)	Pa
Erosions	0.264 (0.06–0.44)	0.008	0.196 (-0.007–0.383)	0.052
Joint space narrowing	0.204 (0.002–0.392)	0.042	0.147 (-0.057–0.340)	0.145
Total	0.238 (0.037–0.421)	0.017	0.182 (-0.02–0.372)	0.069

The serial anti-CCP2 concentration is the mean of three determinations. aSpearman test. CI, confidence interval; M0, month 0; M12, month 12; M36, month 36; r, correlation.

ISSN: 1478-6362