Clinical implications of persistent joint pain after gout flare

Objectives

A subset of gout patients developed persistent joint pain after flares. Analysis of this clinical phenomenon may shed further light on the factors related to worsening gout and even provide clues to its pathogenesis.

Methods

We analyzed the clinical, laboratory, and ultrasound data of gout patients to explore the associations of these data with persistent joint pain after gout flares.

Results

A total of 1029 gout patients were included: 182 (17.7%) patients with persistent joint pain and 847 (82.3%) patients with nonpersistent joint pain. Patients with persistent joint pain had more total involved joints, more gout flares in the past year, and more joints with simultaneous gout flares (P < 0.01). Among the ultrasound-detected lesions, patients with persistent joint pain had a higher incidence of tophus (36.4% vs. 21.1%) and bone erosion (18.6% vs. 8.6%) (P < 0.05). Higher UA and lower TBil were found in patients with persistent joint pain (P < 0.001). Hypertension (54.9% vs. 38.7%) and metabolic syndrome (58.8% vs. 46.4%) were both more frequent in patients with persistent joint pain (P < 0.05). TBil was negatively correlated with the incidence of persistent joint pain (P < 0.001, r = −0.190), UA values (P < 0.001, r = −0.125), and metabolic syndrome scores (P < 0.001, r = −0.192). A correlation curve was fitted using LOESS (locally weighted region).

Conclusion

Persistent joint pain after gout flares is a marker of increased disease burden in gout. The significance of the level of total bilirubin for the exacerbation of gout deserves further study.