Work instability and associated factors among patients with rheumatoid arthritis in Greater Poland

OBJECTIVES: Rheumatoid arthritis (RA) affects patients’ capacity to work. The Rheumatoid Arthritis Work Instability Scale (RA-WIS) is a reliable method to measure work instability (WI) (1–3). We lack data on the relationship between RA and work instability among Polish patients. Our study aimed to assess WI and associated factors among patients with RA. MATERIAL AND METHODS: The authors conducted a multi-centre cross-sectional observational study. 315 patients from three rheumatology centres were enrolled and filled in questionnaires, including demographic and self-reported clinical data, RA-WIS, and the Health Assessment Questionnaire (HAQ). Swollen and tender joint counts (SJC, TJC) were assessed by the attending physician, and current erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were collected. We excluded 41 patients due to an incorrectly filled in form and analysed questionnaires of 274 patients. DAS28 (Disease Activity Score in 28 joints) and DAS28-CRP were calculated. We performed statistical analysis with Statistica v. 13.3 using the Mann-Whitney U test, χ(2) test, and Spearman’s correlation. RESULTS: 140 (51%) patients were currently employed and their characteristics were analysed. In univariable analysis we identified the following risk factors for high risk WI: moderate-to-high disease activity (DAS28 ≥ 3.2 – OR 2.29, 95% CI 1.06–4.96, p = 0.033; DAS28-CRP ≥ 3.2 – OR 2.34, 95% CI 1.04–5.27, p = 0.038), ESR ≥ 30 mm/h in women and ≥ 20 mm/h in men (OR 2.65, 95% CI 1.20–5.89, p = 0.010), CRP ≥ 1 mg/dl (OR 4.02, 95% CI 1.78–9.10, p < 0.001), HAQ-DI > 1.0 (OR 2.23, 95% CI 1.04–4.81, p = 0.037) and at least moderate pain on the visual analogue scale (VAS p ≥ 4.5 cm – OR 5.31, 95% CI 2.36–11.96, p < 0.001). Correlations were moderate between RA-WIS and VASp (RS = 0.59, p < 0.001) and HAQ-DI (RS = 0.52, p < 0.001) but weak with disease activity indices (DAS28 [RS = 0.31, p < 0.001]; DAS28-CRP [RS = 0.28, p < 0.001]). CONCLUSIONS: Pain and disability are the main factors strongly associated with work instability among patients with RA.