Objectives: To identify the determinant of patients' perspectives of quality of life (QOL) and working status out of analysis-derived components underlying a set of assessment measures of the status of patients with rheumatoid arthritis (RA).
Methods: From the NinJa database in Japan (2012-2014), 1455 RA patients with DAS28 > 3.2 were recruited. Components explaining RA status were derived from principal component analysis of 15 assessment measures. Multivariate regression was used to examine the relative contribution of each identified component to the EuroQOL-5 Dimension Questionnaire score and working status.
Results: Among the identified components (patient symptoms, physical disability, evaluated symptoms, patient distress, inflammatory marker, and serological marker), patient distress showed highest contribution to EuroQOL for both male (44.6%) and female patients (39.3%). Physical disability was associated with significantly less participation in paid work in male (odds ratio [OR]; 0.63) and both household and paid work in female (OR; 0.82 and 0.54, respectively), though patient distress showed the strongest association with less participation in both household and paid work in female (OR; 0.64 and 0.45, respectively).
Conclusion: The approach to latent patient distress using psychological screening tools, concurrently with the treatment to control the activity of arthritis, can be help to improve health-related QOL (HRQOL) including work participation.
Keywords: Principal component analysis; psychological distress; quality of life; rheumatoid arthritis; working status.