Flare rate thresholds for patient assessment of gout disease activity states.

Objective To determine the relationship between gout flare rate and self-categorization into remission, low disease activity (LDA), and patient acceptable symptom state (PASS). Methods Patients with gout self-categorised as remission, LDA, and PASS, and reported number of flares over the preceding 6 and 12 months. Multinomial logistic regression was used to determine the association between being in each disease state (LDA and PASS were combined) and flare count and self-reported current flare. A distribution-based approach and extended Youden index identified possible flare count thresholds for each state. Results Investigators from 17 countries recruited 512 participants. Remission was associated with a median recalled flare count of zero over both 6 and 12 months. Each recalled flare reduced the likelihood of self-perceived remission compared with being in higher disease activity than LDA/PASS by 52% for 6 months and 23% for 12 months, and the likelihood of selfperceived LDA/PASS by 15% and 5% for 6 and 12 months, respectively. A threshold of 0 flares in preceding 6 and 12 months was associated with correct classification of self-perceived remission in 58% and 56% of cases, respectively. Conclusion Flares are significantly associated with perceptions of disease activity in gout and zero flares over the prior 6 or 12 months are necessary for most people to self-categorise as being in remission. However, recalled flare counts alone do not correctly classify all patients into selfcategorised disease activity states, suggesting that other factors may also contribute to selfperceived gout disease activity.