Patterns of lung diseases predict survival in patients with MPO-ANCA-associated vasculitis: a single-center...

This study aimed to explore differences in clinical features and prognosis among patients with varied myeloperoxidase (MPO) antineutrophil cytoplasmic antibody-associated vasculitis (MPO-AAV) associated lung diseases.

Patients with MPO-AAV-associated lung diseases were enrolled in this retrospective cohort study at a single center. Clinical features and laboratory data at the time of diagnosis were compared among patients with various lung disease patterns. Kaplan-Meier and Cox regression analyses were performed to analyze overall survival.

A total of 155 patients were finally included and categorized into five groups, as follows: 72 had a usual interstitial pneumonia (UIP) pattern, 40 had non-UIP interstitial pneumonia, 18 had bronchiectasis (BR), 13 had necrotizing granuloma (NG), and 12 had diffuse alveolar hemorrhage (DAH). Among the five groups, patients with DAH had higher dyspnea and hemoptysis frequencies, lower PaO₂/FiO₂ levels, elevated C-reactive protein levels, and the poorest prognosis. The overall survival (OS) in the DAH group (median OS: 3.2 months) was significantly poorer than that in the NG group (median OS: not reached, log rank P < 0.001), the BR group (median OS: not reached, log rank P < 0.001), and the non-UIP IP group (median OS: 61.1 months, log rank P = 0.001). The UIP group had significantly more ex-smokers than the other groups (P < 0.001) and the second poorest survival (median OS: 39.1 months). The NG group tended to have female predominance, a higher incidence of ENT involvement, less severe renal involvement, and the best survival. After adjusting for multi-model Cox regression analysis, DAH and UIP (hazard ratio: 19.301 and 9.940, respectively, compared with NG) were independent predictors of all-cause mortality.

Various patterns of lung disease-associated MPO-AAV may potentially predict patient survival. Key Point • The present study described the clinical and prognostic features of various lung diseases-associated MPO-AAV, indicating the potential prediction for the survival of MPO-AAV patients.