Mortality-related prognostic factors in older adult patients with nontuberculous mycobacterial pulmonary disease: A single centre, retrospective cohort study in Japan

Background: Nontuberculous mycobacterial pulmonary disease (NTM-PD) is becoming increasingly prevalent worldwide and is associated with substantial mortality. However, data on older adult patients with NTM-PD are limited. We aimed to characterize the clinical course and prognostic factors of older adult patients with NTM-PD. Methods: From 2011 to 2025, NTM-PD patients aged 65 years or older at a single centre in Japan were screened, and clinical course and characteristics were reviewed retrospectively. Cox proportional hazards regression analysis and log-rank analyses were performed to identify risk factors for all-cause mortality. Results: A total of 110 older adult patients with NTM-PD were included (deceased group, n = 31; survived group, n = 79). The median age of all patients was 77 years. In univariable analysis, male sex, smoking history, low albumin levels, and high C-reactive protein levels were associated with mortality. In multivariate analysis, smoking history (hazard ratio [HR]: 6.68; 95% confidence interval [CI]: 2.08–21.46) and low albumin level (HR: 3.54; 95% CI: 1.60–7.82) were independently associated with mortality. Log-rank analysis demonstrated poorer survival among patients with low albumin levels and a smoking history. After stratification by sex, smoking history remained associated with mortality in both men and women. Radiologically, mortality was the highest in the unclassified pattern, followed by the fibrocavitary and nodular bronchiectatic patterns. Conclusions: Smoking history and low albumin levels were associated with increased all-cause mortality in older adult patients with NTM-PD. These factors may help identify patients who require closer monitoring.