Elevated serum uric acid is a predictor of pulmonary artery involvement and subsequent prognosis in patients with Takayasu's arteritis.

Objectives: The aim of this study was to investigate the predictive value of uric acid (UA) in prognosis of pulmonary artery involvement (PAI) in patients with Takayasu's arteritis (TAK).

Methods: A total of 166 TAK patients were enrolled in the study, including 76 with PAI and 90 without. Outcomes of 144 TAK patients were followed up and recorded. The possible associations between serum UA levels and incidence of PAI in TAK and PAI-related prognosis of TAK patients were examined using different statistical models.

Results: The serum UA levels were significantly higher in TAK patient with PAI than TAK patients without PAI. Multivariate logistic regression analysis indicated that serum UA level ≥284.5 umol/L was associated with an increasing incidence of PAI in TAK (OR: 2.108, 95% CI: 1.063 to 4.180; p=0.033). Kaplan-Meier survival analysis showed that TAK patients with serum UA level ≥328.1 umol/L had a significantly higher cumulative incidence of PAI-related adverse events compared to TAK patients with serum UA level <328.1 umol/L (p=0.008). Multivariate Cox proportional hazard regression analysis revealed that serum UA level ≥328.1 umol/L (HR: 2.595, 95% CI: 1.198 to 5.622; p=0.016) was a PAI-related prognostic risk factor for TAK.

Conclusions: Elevation of serum UA level was associated with an increasing risk of PAI and PAI-related adverse event in patients with TAK, indicating its potential as a predictor for identification of PAI onset and worsening in TAK patients.