Is the serum oxytocin level altered by treatment in rheumatoid arthritis patients complicated with depression?

Abstract

Objective: The objective of this study was to investigate the factors associated with depression, in-cluding serum oxytocin (OXT) levels, disease activity, activities of daily living (ADL), and quality of life(QOL), and their effects on rheumatoid arthritis (RA).Methods: This study included 42 RA patients who received treatment with a biological agent. Wemeasured the following variables before and after 6 months of treatment: baseline characteristics, in-cluding age, sex, disease duration, smoking, and body mass index (BMI); prednisolone and methotrex-ate dose; serum level of matrix metalloproteinase-3 (MMP-3); erythrocyte sedimentation rate (ESR);and C-reactive protein (CRP) level. The disease activity of RA was assessed using the Simplified DiseaseActivity Index (SDAI); depression was assessed using the Hamilton Depression Rating Scale (HAM-D);ADL was assessed using the Health Assessment Questionnaire; and QOL was assessed using the ShortForm (SF)-36. Serum OXT levels were determined using enzyme-linked immunosorbent assay.Results: The HAM-D score significantly correlated with the SDAI, and the mental component sum-mary (MCS) score of SF-36. However, the serum OXT levels did not correlate with the HAM-D score.Regression analysis using the HAM-D score as the objective variable identified female sex, smoking,BMI, and all the three component scores of SF-36, but not serum OXT levels, as significant factors.Comparisons between before and after treatment showed that the HAM-D score improved from 5 to1.5; however, the serum OXT levels did not change.Conclusion: The variables of female sex, smoking, BMI, and QOL correlated with depression complicat-ed with RA. However, serum OXT levels did not correlate directly.