Background/Purpose: Treatment targets for gout generally focus on serum urate, but patient-centred targets may be equally important. We seek to determine the relationship between gout flare rates and patient self-classification into 3 disease activity states: remission (no symptoms of disease), low disease activity (LDA, no symptoms of disease that require additional therapy), and patient acceptable symptom state (PASS, level of symptoms acceptable to the patient).

Methods: Patients with 2015 ACR/EULAR gout criteria attending rheumatology clinics in 17 countries were asked to recall the number of flares over the preceding 6 and 12 months. For each time horizon they were asked to consider whether they thought their gout had gone away (remission), didn’t require any additional or stronger therapy (LDA) or was controlled to their satisfaction (PASS). Multinomial logistic regression was used to determine the association between being in each disease state, flare count and self-reported current flare. A distribution-based approach and 3-state analysis of the volume under a ROC surface (VUS) with extended Youden index identified possible flare count thresholds for each state.

Results: 512 patients were recruited with mean (SD) age 58 (14) years, 89% were male, and disease duration of 12 (10) years. The states of LDA/PASS were combined since the distribution of recalled flares was very similar for these states. Each recalled flare reduced the likelihood of self-classified remission by 52% for 6 months and 23% for 12 months, and the likelihood of LDA/PASS by 15% and 5% for 6 and 12 months, respectively (Table).  Not currently self-reporting a flare was strongly associated with self-classification into remission (OR 15.20 for 6 months and 15.13 for 12 months) or LDA/PASS (OR 5.74 for 6 months and 5.13 for 12 months) (Table). The VUS for 6-month flare count was 0.41 (95%CI 0.36 to 0.46) and the thresholds identified from the extended Youden index were 0 and 3.5; for 12-month flare count, the VUS was 0.38 (95%CI 0.33 to 0.43) and thresholds were 0 and 4.5. A threshold of 0 flares in preceding 6 and 12 months was associated with accurate classification  of remission in 58% and 56% of cases, respectively.

Conclusion: Recalled flares are significantly associated with patient perceptions of disease activity in gout, supporting flare as an important target of therapy. Zero flares over prior 6 or 12 months were necessary for most patients to self-categorise as remission. Current flare is strongly associated with perception of disease activity, independently of the number of prior flares. However, recalled flare counts alone do not fully predict self-categorised states, suggesting that other factors may also contribute to perception of gout disease activity.