Predictors of treatment initiation in nontuberculous mycobacterial pulmonary disease: a real-life retrospective analysis.

Nontuberculous mycobacterial pulmonary disease (NTM-PD) requires prolonged, complex antimicrobial therapy. Identifying predictors of treatment initiation in routine practice is crucial. We conducted a retrospective observational study of consecutive adults with NTM-PD evaluated at a tertiary referral center between 2021 and 2025. Demographic, clinical, radiological, and microbiological characteristics were compared between patients managed with observation and those who initiated treatment. Multivariate logistic regression identified independent predictors of treatment initiation. Among 317 patients, 176 initiated therapy and 141 were observed. Treatment initiation was independently associated with smear positivity, mixed or cavitary radiological patterns, systemic symptoms, particularly fever and weight loss, and immunosuppression. Airway clearance techniques and isolation of Mycobacterium abscessus were associated with a lower likelihood of treatment initiation. Respiratory symptoms did not influence treatment decision. These findings support current guideline recommendations and provide additional insight into the clinical aspects of the disease.