Validity of simplified disease activity index using CRP titer in comparison to disease activity score-28 joints in Iraqi patients with active Rheumatoid arthritis

Objective: Various factors are known to determine the disease activity in patients with rheumatoid arthritis (RA). The simplified disease activity index (SDAI) is new tool of measurement of disease activity. The present study was designed to assess validity of SDAI using C-reactive protein (CRP) titer in comparison to disease activity score in 28 joints (DAS28) in Iraqi patients with active RA. Methods: Sixty nine Iraqi RA patients were included in this study. All patients were active and fulfilled the ACR (American College of Rheumatology) classification criteria. Full history was taken and complete clinical examination was done for all patients. Patients' age, sex, number of swollen joints, visual analogue scale (VAS), and evaluators global assessment (EGA) were documented. Laboratory analysis included erythrocyte sedimentation rate (ESR), CRP, SDAI and DAS28 were measured to assess disease activity. Results: The results revealed direct significant correlation between SDAI and DAS28 (r = 0.903, p < 0.001), and reported a good agreement between SDAI and DAS28 (κ = 0.777, p < 0.001). SDAI was found as a valid measure for disease activity using CRP as a screening test compared to DAS28 (AUC = 0.983, p < 0.001). Conclusion: SDAI is a valid and sensitive measure for assessment of rheumatoid arthritis disease activity that is comparable with the DAS28 using semi quantitative method to estimate CRP. [J Exp Integr Med 2012; 2(3.000): 231-236]