Risk Factors and Long-term Prognosis for Coinfection of Nontuberculous Mycobacterial Pulmonary Disease and Chronic Pulmonary Aspergillosis: A Multicenter Observational Study in Japan

Abstract Background and objective Nontuberculous mycobacterial pulmonary disease (NTM-PD) is a chronic respiratory infection with increasing prevalence and mortality worldwide. Chronic pulmonary aspergillosis (CPA) is a significant complication of NTM-PD and is associated with a poor prognosis. In this multicenter, retrospective, cohort study, we examined the epidemiology, comorbidities, risk factors for CPA coinfection, and long-term prognoses of patients with NTM-PD infected with CPA in Japan. Methods Patients aged ≥ 8 years with newly diagnosed NTM-PD who visited 18 acute-care hospitals in Kyushu, Japan, between 2010 and 2017 were included. Medical records were reviewed for patient characteristics, underlying diseases, mycobacterial species, laboratory data, radiological features, Aspergillus coinfection, and all-cause mortality. Risk factors for CPA coinfection were analyzed using multiple logistic regression, and survival analysis was performed before and after propensity score matching with risk factors. Results Among 1,304 patients with NTM-PD, 45 (3.5%) were diagnosed with CPA during the observation period. Risk factors for CPA coinfection included male sex, chronic obstructive pulmonary disease, oral corticosteroid use, and cavity formation. All-cause mortality was significantly higher in patients with NTM-PD with CPA than in those without CPA (log-rank test, P < .001; crude HR, 3.98). Survival analysis after propensity score matching confirmed that CPA was an independent poor prognostic factor (log-rank test, P = .036; adjusted HR, 1.59). Conclusion CPA is an independent poor prognostic factor in patients with NTM-PD. Clinicians must consider CPA when treating patients with NTM-PD, particularly those with high-risk factors, to ensure their timely diagnosis and management. Summary at a Glance A study of 1,304 NTM-PD patients in Japan found that 3.5% had chronic pulmonary aspergillosis (CPA), significantly increasing their mortality risk. Key risk factors for CPA included male sex, COPD, corticosteroid use, and cavity formation. CPA is an independent poor prognostic factor, highlighting the need for timely diagnosis and management.