Evaluating the Prognostic Role of MRI in Early Rheumatoid Arthritis

Title:

Evaluating the Prognostic Role of MRI in Early Rheumatoid Arthritis

Author(s):

L. G. Suter, R. S. Braithwaite, L. Fraenkel. Yale University, New Haven, CT

Purpose: There is a strong push in the United States to incorporate MRI in the care of patients with RA, as evident by a 245% increase in nonradiologist ownership of outpatient MRIs from 2000 to 2005. Our objective was to evaluate the evidence supporting the use of MRI for prognosis in early RA.

Methods: We used Cochrane Collaboration systematic review guidelines and employed a broad search strategy using medical subject headings (MeSH) “exp Magnetic Resonance Imaging/” and “exp Arthritis/”. We searched Ovid, Cochrane Central Register of Controlled Trials and CINAHL databases. We manually searched: 1) bibliographies of included studies and review articles within the last three years, 2) abstracts and meeting proceedings of relevant journals and professional societies within the last three years, and 3) ClinicalTrials.gov. We included studies that prospectively collected MRI, radiographic and clinical data on early RA patients. Study quality was assessed by adjustment for disease severity and treatment, the length of follow-up, and the use of validated MRI scoring.

Results: The search strategy is shown in Figure 1. Twenty-seven studies met inclusion criteria: 14 did not adequately adjust for disease severity and treatment; 6 had fewer than 6 months of follow-up; and 2 did not use validated scoring. The 5 studies remaining comprised 217 patients with mean disease duration < 9 months and mean follow-up of 1.5 years. Four were therapeutic trials that collected MRI data (one was only in abstract form) and one was an observational cohort study, the only study with a stated objective to evaluate the ability of MRI to predict x-ray erosions. None reported associations between baseline MRI scores and follow-up clinical outcomes. Radiographic and MRI progression in the four peer-reviewed studies was minimal, with maximal increases in mean total Sharp score and OMERACT erosion scores below published smallest detectable differences. The fifth study (an abstract) of 89 patients with < 6 months of disease found that baseline MRI bone marrow edema scores were the only independent predictor of two-year Sharp scores, but 48% of patients had baseline radiographic erosions, suggesting that patients had more severe disease at study onset.

Conclusions: There is inadequate data delineating the prognostic capability of MRI in early RA to support its widespread utilization at this time. Available data are limited by small sample and effect sizes, short follow-up and lack of adjustment for disease severity and treatment. Further evaluation of the prognostic capacity of MRI in early RA is needed with larger studies, multi-year follow-up and adjustment for disease severity and treatment.

Disclosures:

L.G. Suter, None; R.S. Braithwaite, None; L. Fraenkel, None.