Haavardsholm EA, Østergaard M, Hammer HB et al. Ann Rheum Dis 2009;68:1572–9.
Evaluation of new treatments needs a responsive measurement of change. This enables the treating physician (in this case, the rheumatologist) to determine as accurately as possible the response of a patient, and allows government/industry to evaluate the smallest possible sample sizes in the investigation of new drugs. In this comparative study of clinical measures, conventional radiography, ultrasound and magnetic resonance imaging (MRI), it was observed that the most responsive measure of inflammation was a composite measure comprising MRI-determined synovitis, tenosynovitis, and bone marrow edema.
In this investigation, the responsiveness of magnetic resonance imaging (MRI) and ultrasonography, in terms of treatment response, was compared with conventional measures of disease activity and structural damage in 36 patients with rheumatoid arthritis (RA) during the first year of treatment with an anti-tumor necrosis factor (anti-TNF) agent. Measurements were taken at baseline and every 3 months for 1 year. MRI synovitis (one wrist) and the MRI total inflammation score comprising synovitis, tenosynovitis, and bone marrow edema were found to be highly responsive. Moderate responsiveness was found for MRI tenosynovitis and bone marrow edema, each of the composite clinical indices (28-joint count disease activity score [DAS28], simplified disease activity index [SDAI], and clinical disease activity index [CDAI]), and the 28-swollen joint count. Ultrasonography (one wrist) displayed low-to-moderate responsiveness. With regard to measures reflecting structural damage, the MRI erosion score was more responsive than conventional radiography; however, responsiveness was still low.