Functional Disability and Its Determinants in Ecuadorian Patients with Rheumatoid Arthritis

Introduction: Disability in RA is associated with loss of workdays, greater use of health resources and a higher prevalence of depression. The purpose of this study was to determine the prevalence of functional disability and the factors associated with it. Methods: A cross-sectional study was carried out during January-June 2019 at a rheumatology clinic in the city of Guayaquil. Patients with pre-established RA were included. Functional disability was measured using the HAQ-DI. Data were analyzed using the statistical program SPSS v22. We compared characteristics between patients with and without disability using Student's t-test and chi-square. A multiple logistic regression model for functional disability was made. Results: We included 395 patients, 87.8% female and 12.2% male with a mean age of 51.4 +/- 12 years and mean duration of disease 13.8 +/- 7 years. Most patients had extra-articular manifestations (80.8%) and comorbidities (81.3%). The mean HAQ-DI was 0.8 +/- 0.9, with a prevalence of disability of 26.6%. We found a statistically significant relationship between disability and female sex (p=0.018), age (p=0.020), presence of extra-articular manifestations (p=0.008), myalgia (p<0.001) and fatigue (p<0.001). In addition, patients with disabilities had a lower employment rate (26.7%) compared to those without disability (45.5%, p=0.001). In the multi-variate logistic analysis, only depression (p=0.029), diabetes (p=0.003), SJC (p=0.001) and VAS of pain (p=0.004) were significantly related to functional disability. Conclusion: Disability affects a quarter of patients with RA. Among the determinants of disability, we found female sex, older age, grade of pain, inflammatory markers and the level of disease activity.