Utility of administrative and clinical data to predict major change in medical treatment in US Veterans enrolled in the Veterans Affairs Rheumatoid Arthritis (VARA) registry.

ABSTRACT

OBJECTIVES: To examine factors associated with major therapeutic changes (MTC) among US Veterans with moderate/severe rheumatoid arthritis (RA) based on Disease Activity Score based on 28 joints (DAS28). METHODS: We used data from patients enrolled in the Veterans Affairs Rheumatoid Arthritis (VARA) registry from 1/1/2006 through 12/31/2014. The index date was a clinic visit with DAS28 >3.2 (moderate/severe disease) following an 18-month pre-index period that included ≥2 DAS28 measurements ≥60 days apart. The patients were followed for MTC from 7 days pre-index through 90 days post-index. Poisson multivariable regression models were used to identify associations with MTC. Chart review of a subset of randomly selected patients explored factors that impacted therapeutic decisions. RESULTS: Among 941 patients, 396 (42.1%) had MTC. Of these, 369 (39.2%) patients had worsening DAS28 at index, 118 (12.5%) had DAS28 improvements, and 454 (48.2%) patients had no change in DAS28 versus pre-index DAS28. Of the patients with worsening DAS28, no change in DAS28, and improved DAS28, respectively, 50.5%, 62.6%, and 70.3% had no MTC. Regression analyses showed index DAS28, oral steroid or non-biologic disease-modifying anti-rheumatic drug (nbDMARD) use in the previous year were associated with an increased likelihood of MTC; use of nbDMARDs in the previous 90 days was associated with a decreased likelihood of MTC. The most common reason for not modifying therapy despite DAS28 >3.2 was a judgement of mild disease. CONCLUSIONS: Clinicians frequently do not institute major therapeutic changes despite DAS28 indicating moderate/severe disease activity; multiple factors are involved in real-world treatment decisions.