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<div><p>Objective</p><p>The purpose of this study was to assess the health-related quality of life (HRQOL) and investigate the variables contributing to reduced HRQOL in patients with rheumatoid arthritis.</p><p>Methods</p><p>The present cross-sectional study was conducted on patients diagnosed with rheumatoid arthritis at two teaching hospitals in Jordan using a convenience sampling technique. The participants were interviewed face-to-face during the scheduled appointment at the outpatient rheumatology clinic. The HRQOL was evaluated by the validated EuroQol-5 Dimension (EQ-5D) questionnaire, which included the EQ-5D utility index that evaluated HRQOL in terms of 5 domains, including mobility, self-care, usual activities, pain/discomfort, and anxiety/depression, and the EQ-5D visual analogue scale (EQ-5D<sub>VAS</sub>), which evaluated HRQOL on a vertical scale ranging from 0 (worst imaginable health) to 100 (best imaginable health). The validated short version of the 19-item Compliance Questionnaire for Rheumatology (CQR-5) was used to evaluate medication adherence. The Clinical Disease Activity Index (CDAI) was used to assess disease activity among the study participants. A stepwise quantile regression model (q = 0.5) was conducted to explore the factors associated with the EQ-5D<sub>Utility Index</sub> and EQ-5D<sub>VAS</sub> scores.</p><p>Results</p><p>In total, 261 patients with RA participated in the study. The median (interquartile range) of the EQ-5D<sub>Utility Index</sub> and EQ-VAS scores was 0.552 (0.006–0.726) and 0.506 (0.233–0.690), respectively. Regression analysis results demonstrated that medication non-adherence (regression coefficient (β) = -0.348, P<0.01), not performing regular physical activity (β = -0.209, P<0.01), and higher disease activity as measured by the CDAI score (β = -0.015, P<0.01) were significant predictors of a lower EQ-5D<sub>Utility Index</sub> score<sub>.</sub> In addition, medication non-adherence (β = -0.199, P<0.01), not performing regular physical activity (β = -0.117, P<0.01), increased body mass index (BMI) (β = -0.009, P<0.01), and higher CDAI score (β = -0.009, P<0.01) were significant predictors of low EQ-5D<sub>VAS</sub> score.</p><p>Conclusions</p><p>Patients with RA experienced significantly impaired HRQOL. Medication non-adherence, not performing regular physical activity, increased body weight, and increased disease activity were identified as determinants of poor HRQOL among patients with RA in the present study. Treating physicians should encourage regular physical activity, maintaining a healthy body weight, and controlling disease activity to improve HRQOL in patients with RA.</p></div>