Search

Despite the recognition that tophus regression is an important outcome measure in clinical trials of chronic gout, there is no agreed method of tophus measurement. A number of methods have been used in clinical trials of chronic gout, from simple physical measurement techniques to complex advanced imaging methods. This paper summarises the methods of tophus measurement that have been used and discusses the properties of these methods. Physical measurement using Vernier calipers fulfils most aspects of the Outcomes Measures in Rheumatology (OMERACT) filter. Rigorous testing of the complex methods, particularly with respect to reliability and sensitivity to change is needed, to determine the appropriate use of these methods. Further information is also required regarding which method of physical measurement is best for use in future clinical trials. The need to develop and test a patient reported measure of tophus burden is also highlighted.

Objective.To summarize the endorsement of measures of patient-reported outcome (PRO) domains in chronic gout at the 2010 Outcome Measures in Rheumatology Meeting (OMERACT 10).Methods.During the OMERACT 10 gout workshop, validation data were presented for key PRO domains including pain [pain by visual analog scale (VAS)], patient global (patient global VAS), activity limitation [Health Assessment Questionnaire-Disability Index (HAQ-DI)], and a disease-specific measure, the Gout Assessment Questionnaire version 2.0 (GAQ v2.0). Data were presented on all 3 aspects of the OMERACT filters of truth, discrimination, and feasibility. One PRO, health-related quality of life measurement with the Medical Outcomes Study Short-form 36 (SF-36), was previously endorsed at OMERACT 9.Results.One measure for each of the 3 PRO of pain, patient global, and activity limitation was endorsed by > 70% of the OMERACT delegates to have appropriate validation data. Specifically, pain measurement by VAS was endorsed by 85%, patient global assessment by VAS by 73%, and activity limitation by HAQ-DI by 71%. GAQ v2.0 received 30% vote and was not endorsed due to several concerns including low internal consistency and lack of familiarity with the measure. More validation studies are needed for this measure.Conclusion.With the endorsement of one measure each for pain, patient global, SF-36, and activity limitation, all 4 PRO for chronic gout have been endorsed. Future validation studies are needed for the disease-specific measure, GAQ v2.0. Validation for PRO for acute gout will be the focus of the next validation exercise for the OMERACT gout group.

Objective.To review a novel approach for constructing composite response criteria for use in chronic gout clinical trials that implements a method of multicriteria decision-making.Methods.Preliminary work with paper patient profiles led to a restricted set of core-set domains that were examined using 1000MindsTM by rheumatologists with an interest in gout, and (separately) by OMERACT registrants prior to OMERACT 10. These results and the 1000Minds approach were discussed during OMERACT 10 to help guide next steps in developing composite response criteria.Results.There were differences in how individual indicators of response were weighted between gout experts and OMERACT registrants. Gout experts placed more weight upon changes in uric acid levels, whereas OMERACT registrants placed more weight upon reducing flares. Discussion highlighted the need for a “pain” domain to be included, for “worsening” to be an additional level within each indicator, for a group process to determine the decision-making within a 1000Minds exercise, and for the value of patient involvement.Conclusion.Although there was not unanimous support for the 1000Minds approach to inform the construction of composite response criteria, there is sufficient interest to justify ongoing development of this methodology and its application to real clinical trial data.

To the Editor: We thank Drs. Dalbeth and McQueen for their kind comments1 on our recent article on radiographic bone damage between chronic gout and inflammatory cytokines2. We assessed radiographic damage of the involved foot joints in patients with chronic gout according to the modified Sharp/van der Heijde … Address correspondence to Dr. S-K. Kim, Department of Internal Medicine, Arthritis and Autoimmunity Research Center, Catholic University of Daegu School of Medicine, 3056-6 Daemyung 4-Dong, Namgu, Daegu 705-718, Republic of Korea. E-mail: kimsk714{at}cu.ac.kr