Background Depression and anxiety have been recognized as prevalent in patients with rheumatoid arthritis (RA), but the exact prevalence among Japanese RA patients is unclear.
Objectives We aimed to analyze the prevalence and factors associated with depression and anxiety in RA patients using data from a large Japanese cohort database.
Methods The 7,479 patients analyzed in this study were enrolled in the National Database of Rheumatic Diseases by iR-net in Japan (NinJa database), one of the largest clinical databases for RA patients in Japan during the fiscal year of 2013 with results from the Hospital Anxiety and Depression Scale (HADS). For depression, RA patients were divided into two groups: a depression group (DG) with score ≥11, suggesting probable depression; and non-DG, with score ≤10. Differences in clinical data were analyzed between groups. For anxiety, an anxiety group (AG) with score ≥11 and non-AG with score ≤10 were also analyzed.
Results The frequency of DG was 9.2%, which is the same as the frequency in the previous year (9.3%) and that of AG 7.0%, which was lower than that in the previous year (8.6%). Mean age was significantly higher in DG and AG than in non-DG and non-AG. In addition, DG and AG showed significantly longer duration of disease, modified Health Assessment Questionnaire (mHAQ) score and higher disease activity score 28 using C-reactive protein (DAS28-CRP), than in non-DG. Furthermore, DG showed a higher stage of progression of joint damage and a higher class of functional impairment. Univariate analyses identified mHAQ and class of functional impairment as factors independently associated with DG and AG. Multivariate logistic regression analyses identified mHAQ as factors independently associated with DG (p<0.001, odds ratio (OR) 1.870, 95% confidence interval (CI) 1.492-2.344). Similar results were observed for tender joint count and patients' global assessment (p<0.01, OR 1.067, 95%CI 1.020-1.115). Work or housework (p<0.05, OR 0.755, 95%CI 0.607-0.939) and age (p<0.001, OR 0.984, 95%CI 0.977-0.992) were observed as negative factors for DG. Likewise, mHAQ was observed as independently associated with AG (p<0.001, OR 2.297, 95%CI 1.796-2.939). Similar results were observed for female sex (p<0.005, OR 1.795, 95%CI 1.281-2.516) and patients' pain assessment ((p<0.001, OR 1.176, 95%CI 1.0120-1.236).
Conclusions On this study the prevalence of two important constructs, depression and anxiety, in Japanese RA patients were examined using NinJa 2013 database. Some differences were identified between factors for depression and those for anxiety. These findings suggested that anxiety should be considered as a distinct construct in RA patients.
Covic et al. BMC Psychiatry 2012, 12:6.
Acknowledgements We thank all members of iR-net (Division of Rheumatology, Immunological Disorder Network of National Hospital Organization).
Disclosure of Interest None declared