Development and First Validation of a Disease Activity Score for Gout

Carlo Alberto Scirè, Greta Carrara, Cinzia Viroli, Marco A. Cimmino, W. J. Taylor, Maria Cristina Manara, M. Govoni, F. Salaffi, L. Punzi, Carlomaurizio Montecucco, Marco Matucci-Cerinic, G. Minisola, Alarico Ariani, Alessandra Galossi, Ciro Lauriti, Elena Fracassi, Luca Idolazzi, M. Bardelli, E. Selvi, Enrico TirriFederica Furini, F. Inverardi, Andrea Calabrò, F. Porta, Raffaele Bittelli, Francesco Venturino, F. Capsoni, I. Prevete, Gian D. Sebastiani, Carlo Selmi, Carlo Francesco Selmi, Giovanni D'Avola, Giulia Botticella, Francesca Serale, Giulia Seminara, Giuseppe D'Alessandro, Leonardo Santo, Lorena Longato, Eleonora Zaccara, L. Sinigaglia, Marco Atteritano, M. Broggini, Marta Caprioli, Marta Favero, Salvatore Sallì, Marco Scarati, Simone Parisi, Nazzarena Malavolta, Stefania Corvaglia, Salvatore Scarpato, Vittorio Veneto

Research output: Contribution to journalArticlepeer-review

Abstract

Objective: To develop a new composite disease activity score for gout and provide its first validation. Methods: Disease activity has been defined as the ongoing presence of urate deposits that lead to acute arthritis and joint damage. Every measure for each Outcome Measures in Rheumatology core domain was considered. A 3-step approach (factor analysis, linear discriminant analysis, and linear regression) was applied to derive the Gout Activity Score (GAS). Decision to change treatment or 6-month flare count were used as the surrogate criteria of high disease activity. Baseline and 12-month followup data of 446 patients included in the Kick-Off of the Italian Network for Gout cohort were used. Construct- and criterion-related validity were tested. External validation on an independent sample is reported. Results: Factor analysis identified 5 factors: patient-reported outcomes, joint examination, flares, tophi, and serum uric acid (sUA). Discriminant function analysis resulted in a correct classification of 79%. Linear regression analysis identified a first candidate GAS including 12-month flare count, sUA, visual analog scale (VAS) of pain, VAS global activity assessment, swollen and tender joint counts, and a cumulative measure of tophi. Alternative scores were also developed. The developed GAS demonstrated a good correlation with functional disability (criterion validity) and discrimination between patient- and physician-reported measures of active disease (construct validity). The results were reproduced in the external sample. Conclusion: This study developed and validated a composite measure of disease activity in gout. Further testing is required to confirm its generalizability, responsiveness, and usefulness in assisting with clinical decisions.

Original languageEnglish
Pages (from-to)1530-1537
Number of pages8
JournalArthritis Care and Research
Volume68
Issue number10
DOIs
Publication statusPublished - Oct 1 2016

ASJC Scopus subject areas

  • Rheumatology

Fingerprint Dive into the research topics of 'Development and First Validation of a Disease Activity Score for Gout'. Together they form a unique fingerprint.

Cite this