 |
|
|
 |
Predictors of Clinical Response to Intraarticular Hylan Injections — A Prospective Study Using Synovial Fluid Measures, Clinical Outcomes, and Magnetic Resonance Imaging ANANTHILA ANANDACOOMARASAMY, HANISH BAGGA, CHANGHAI DING, DANIEL BURKHARDT, PHILIP N. SAMBROOK, and LYN M. MARCH
ABSTRACT. Methods. Thirty-two patients with mild to moderate osteoarthritis (OA) of the knee [OsteoArthritis Research Society International (OARSI) grades I-II] were followed over 6 months. SF and clinical and radiographic measures were assessed. Patella and tibial cartilage volume and cartilage defect scores were measured at baseline and 6 months using magnetic resonance imaging (MRI). The primary outcome measure was the relationship between SF measures and clinical response as defined by the OARSI-Outcome Measures in Rheumatology Clinical Trials responder criteria for OA ("High improvement" ≥ 50% improvement in pain or function; absolute change ≥ 20 NU on Western Ontario and McMaster University Osteoarthritis Index questionnaire). Secondary outcomes included MRI outcomes (change in cartilage volume and cartilage defect scores). Results. Fifteen patients achieved "High improvement." High baseline SF hyaluronic acid (HA) concentration was a statistically significant predictor of clinical response with odds ratio (OR) 6.04 (p < 0.02). HA concentration was divided into tertiles and fitted to a univariate regression model against clinical response. A baseline HA concentration value of > 2 mg/ml provided the greatest tradeoff between sensitivity and specificity with values of 60% and 77%, respectively, a likelihood ratio of 2.55, and OR of 4.88. Baseline clinical and radiological measures did not predict clinical response in this cohort with mild to moderate OA. Nineteen subjects had MRI at both timepoints. No change was noted in cartilage volumes or cartilage defect scores over 6 months. There was no association between baseline HA concentration and baseline cartilage volume. Conclusion. Baseline SF HA concentration predicts clinical response in patients receiving intraarticular Hylan. This has implications for the selection of patients who are likely to respond to this therapy. (J Rheumatol First Release Feb 15 2008) Key Indexing Terms:
HYALURONIC ACID From the Institute of Bone and Joint Research, Royal North Shore Hospital, University of Sydney, Sydney; and Menzies Research Institute, University of Tasmania, Hobart, Australia. Dr. Anandacoomarasamy holds a National Health and Medical Research Council Medical Postgraduate Research Scholarship (no. 402901). Our study was supported by a grant from Bayer Pharmaceuticals Australia and Genzyme Corporation. Dr. Bagga was a recipient of a Doctoral Scholarship from the Lincoln Centre for Research into Bone and Joint Disease. A. Anandacoomarasamy, MBBS (Hons), BSc (Med), FRACP, Research Fellow; P.N. Sambrook, MBBS, FRACP, Phd, LLB, Professor; L.M. March, MBBS, FRACP, PhD, MSc, FAFPHM, Associate Professor, Institute of Bone and Joint Research; D. Burkhardt, BSc, Senior Scientist, Raymond Purves Laboratory, Royal North Shore Hospital, University of Sydney; H. Bagga, BMed, FRACP, Consultant Rheumatologist, Rural Clinical School, University of New South Wales, Coffs Harbour; C. Ding, MBBS, MD, Senior Research Fellow, Menzies Research Institute. Address reprint requests to Prof. L. March, Department of Rheumatology, Royal North Shore Hospital, St Leonard's, NSW 2065, Australia. Accepted for publication October 24, 2007.
|
