Responsiveness of patient-reported outcomes measurement information system measures in rheumatoid arthritis patients starting or switching a disease-modifying antirheumatic drug

Objective. The Patient-Reported Outcomes Measurement Information System (PROMIS) is a calibrated item bank used to assess patient-reported outcomes across multiple domains. The purpose of this study was to describe the performance of selected PROMIS measures in patients with rheumatoid arthritis (RA) with active disease who were initiating a disease-modifying antirheumatic drug (DMARD). Methods. Participants in an ongoing prospective observational study completed 8 PROMIS measures before and after DMARD initiation. Linear regression models were performed to identify cross-sectional associations between baseline PROMIS measures and disease activity, measured using the Clinical Disease Activity Index (CDAI). Paired t-tests were performed to evaluate responsiveness after 12 weeks of DMARD treatment. Associations between changes in PROMIS measures and changes in the CDAI score were assessed using linear regression. Results. Among the 156 participants who completed the first study visit, the mean ± SD baseline CDAI score was 25.5 ± 14.0. Baseline scores for PROMIS measures of physical health, pain, and sleep were associated with the baseline CDAI score (P ≤ 0.05). Among the 106 participants with 12-week data, all PROMIS scores improved after DMARD initiation (P ≤ 0.05). With the exception of depression, changes in all assessed PROMIS measures were correlated with changes in the CDAI score (standardized βs from |0.23| to |0.38|). Conclusion. These data provide support for the utility of PROMIS measures for the assessment of physical and mental health in individuals with active RA. All PROMIS measures improved significantly after DMARD initiation, with the magnitudes of association between changes in PROMIS measures and changes in the CDAI score in the low-to- moderate range.