York Kiat Tan1,2,3, HuiHua Li4, John Carson Allen5, Julian Thumboo1,2,3,4. 1. Department of Rheumatology and Immunology, Singapore General Hospital, Singapore. 2. Duke-NUS Medical School, Singapore. 3. Yong Loo Lin School of Medicine, National University of Singapore, Singapore. 4. Health Services Research Unit, Singapore General Hospital, Singapore. 5. Centre for Quantitative Medicine, Duke-NUS Medical School, Singapore.
Abstract
AIM: To investigate anti-cyclic citrullinated peptide (anti-CCP) and rheumatoid factor (RF) in relation to ultrasound-detected joint inflammation and bone erosion in patients with rheumatoid arthritis (RA) as previous studies have mainly utilized radiographic damage as imaging outcomes. METHOD: In this cross-sectional study, patients were grouped based on their Disease Activity Score at 28 joints (DAS28 < 3.2, DAS28 ≥ 3.2). Ultrasound variables (power Doppler and gray scale joint inflammation graded 0-3 semi-quantitatively; bone erosion graded Yes = 1/No = 0 dichotomously) were correlated with antibodies levels using Pearson correlation. Simple linear regression was used to characterize relationships between variables. Receiver operating characteristic (ROC) analysis was performed to determine statistically optimal cut-off values for identifying patient subgroups with ultrasound erosion scores >25th, >50th and >75th percentiles. RESULTS: One thousand and eighty joints and 1800 joint recesses from 36 peripheral joint sites were scanned in 30 adult RA patients (mean disease duration, 70.3 months; 93.3% female; 93.3% anti-CCP positive; 93.3% RF positive). In the DAS28 < 3.2 group, no significant correlations were found between antibody levels and ultrasound variables. In the DAS28 ≥ 3.2 group, anti-CCP levels correlated significantly (r = 0.46, P = .048) and were predictive (P = .048) of ultrasound erosion scores. Area under the ROC curve based on cut-off anti-CCP level of ≥95.2 to identify patients with ultrasound erosion scores >7 (75th percentile) was 0.72 (sensitivity = 83.3%, specificity = 53.8%). CONCLUSION: The association of anti-CCP and RF with joint damage appears to differ in RA. Among patients with at least moderate disease activity (DAS28 ≥ 3.2), anti-CCP-but not RF-is associated with joint damage, being moderately correlated with ultrasound-detected bone erosion.
AIM: To investigate anti-cyclic citrullinated peptide (anti-CCP) and rheumatoid factor (RF) in relation to ultrasound-detected joint inflammation and bone erosion in patients with rheumatoid arthritis (RA) as previous studies have mainly utilized radiographic damage as imaging outcomes. METHOD: In this cross-sectional study, patients were grouped based on their Disease Activity Score at 28 joints (DAS28 < 3.2, DAS28 ≥ 3.2). Ultrasound variables (power Doppler and gray scale joint inflammation graded 0-3 semi-quantitatively; bone erosion graded Yes = 1/No = 0 dichotomously) were correlated with antibodies levels using Pearson correlation. Simple linear regression was used to characterize relationships between variables. Receiver operating characteristic (ROC) analysis was performed to determine statistically optimal cut-off values for identifying patient subgroups with ultrasound erosion scores >25th, >50th and >75th percentiles. RESULTS: One thousand and eighty joints and 1800 joint recesses from 36 peripheral joint sites were scanned in 30 adult RApatients (mean disease duration, 70.3 months; 93.3% female; 93.3% anti-CCP positive; 93.3% RF positive). In the DAS28 < 3.2 group, no significant correlations were found between antibody levels and ultrasound variables. In the DAS28 ≥ 3.2 group, anti-CCP levels correlated significantly (r = 0.46, P = .048) and were predictive (P = .048) of ultrasound erosion scores. Area under the ROC curve based on cut-off anti-CCP level of ≥95.2 to identify patients with ultrasound erosion scores >7 (75th percentile) was 0.72 (sensitivity = 83.3%, specificity = 53.8%). CONCLUSION: The association of anti-CCP and RF with joint damage appears to differ in RA. Among patients with at least moderate disease activity (DAS28 ≥ 3.2), anti-CCP-but not RF-is associated with joint damage, being moderately correlated with ultrasound-detected bone erosion.
Authors: Thomas Dörner; Edward M Vital; Sarah Ohrndorf; Rieke Alten; Natalia Bello; Ewa Haladyj; Gerd Burmester Journal: Rheumatol Ther Date: 2022-03-31