Correlation of Clinical Disease Activity Score with Ultrasound Disease Activity Score in Rheumatoid Arthritis Patients of Kashmir Valley

Abstract

Abstract Background: Musculoskeletal ultrasound can aid in assessing disease activity and deciding to taper off disease-modifying antirheumatic drugs in patients of rheumatoid arthritis (RA). With this background, we conducted a study to compare Clinical Disease Activity Score 28 C-reactive protein (DAS28 CRP) with Ultrasound Disease Activity Score 28 CRP (USDAS28 CRP) and its correlation with disease parameters in RA patients. Materials and Methods: Forty-eight RA patients were subjected to clinical and ultrasound assessment of disease activity after subjecting them to history, clinical, and laboratory investigations. The clinical assessment was done by DAS28 CRP and the US assessment was done by USDAS28 CRP score. The swollen joint count and the tender joint count were replaced by GSUS (grayscale ultrasound) score and power Doppler ultrasound score, respectively, in USDAS28 CRP score. Results: The mean age of the patients was 46.31 ± 13.90 years, with a mean duration of illness being 98.3 months. Nineteen patients had inactive disease and 29 patients had active disease on clinical examination. Six out of 19 (31.6%) patients with the inactive disease on clinical assessment had activity (subclinical synovitis) on US assessment. Two out of 29 (6.89%) patients with the active disease on clinical assessment had inactive disease on US assessment. Patients with subclinical synovitis had a longer disease duration (154 ± 114.2 vs. 73.38 ± 54.9 months, P = 0.05) and higher erythrocyte sedimentation rate (28.5[23] vs. 15[5] mm/H, P = 0.017) as compared to RA patients with the inactive disease on US assessment. Correlations between clinical scales and ultrasound scales were good (Pearson’s r = 0.832, P = 0.01). Conclusion: US scoring for disease assessment is a plausible method to assess subclinical activity in RA patients with inactive disease.