Serum C-Reactive Protein to Albumin Ratio in Egyptian Rheumatoid Arthritis Patients and its Relation to Disease Activity, Physical Function and Psychological Status

Abstract Background: Rheumatoid arthritis (RA) is an autoimmune disease that involves small peripheral joints in a bilateral and symmetric pattern. In RA, joint destruction and/or physical dis-abilities are associated with a reduced quality of life (QOL) and premature death. C-reactive protein (CRP) is an acute phase reactant, which is mainly synthesized by the liver. Its synthesis is induced by pro-inflammatory cytokines. On the other hand, albumin breakdown is enhanced in the inflammatory states, leading to reduced albumin concentrations. The CRP/Albumin ratio (CRP/Alb-R) is an indicator of the degree and activity of several inflammatory conditions and is believed to be superior to CRP or albumin alone in monitoring inflammation. Aim of Study: To investigate CRP/Alb-R in RA patients and its association with disease activity (DA), physical state, and psychological state. Subjects and Methods: This case-control study enrolled 71 RA cases and 71 matched healthy subjects. The clinical and serological markers of disease activity were recorded, and DA score-28 CRP (DAS-28 CRP) was calculated to determine DA in cases with RA. The CRP/Alb-R underwent calculation and was compared among both groups. The functional state was as-sessed using the Health Assessment Questionnaire Disability Index (HAQ-DI). Anxiety and depression levels underwent assessment with the Hospital Anxiety and Depression Scale (HADS) questionnaire. Results: RA cases had significantly higher CRP/Alb-R than controls (p<0.001). CRP/Alb-R had a significant correlation with clinical parameters and serological markers of DA as well as the DAS28 in RA cases. The ROC curve analysis demon-strated a significant ability of the CRP/Alb-R to discriminate active and inactive RA patients based on DAS28-CRP with an area under curve (AUC) = 0.842, stronger than CRP or serum albumin alone. CRP/Alb-R had a significant correlation with HAQ-DI score, HADS-Depression score and HADS-Anxiety score among RA cases (p<0.001, p=0.042 and p=0.032, respec-tively). In the linear regression analysis, CRP/Alb-R was found to be the strongest determinant that can predict the DAS28-CRP and DAS28-ESR compared to CRP or serum albumin alone. Conclusion: RA cases had significantly higher CRP/Alb-R compared to healthy controls. CRP/Alb-R can be a promising marker for assessment of RA activity, effect of RA on func-tional state and psychological affection in RA patients. CRP/ Alb-R was superior to CRP or albumin alone in discriminating active and inactive RA cases and in prediction of RA activity.