Comparative study of clinical features between elderly and non-elderly patients with pulmonary nontuberculous mycobacterial disease

Objective: To compare the clinical features between elderly amd non-elderly patients with pulmonary nontuberculous mycobacterial (NTM) disease. Patients: The subjects consisted of 114 patients over 75 years (elderly) and 193 patients under 74 years (non-elderly) with pulmonary NTM disease diagnosed with criteria proposed by ATS between 2008 and 2019. Results: The ratio of males/females was higher in elderly than non-elderly patients. The presence of underlying diseases was more frequent in elderly than non-elderly patients. The detection method frequently involved periodical health examinations in non-elderly patients and bronchoscopy was positively performed for a definite diagnosis. Regarding laboratory findings, the positive response rate of MAC antibody was similar in both patient groups. The causative microorganism was frequently M.intracellulare in elderly patients and M.kansasii in non-elderly patients. Although small nodules with bronchiectasis were frewuntly noted in non-elderly patients as radiological findings, there were no significant differences. Combined chemotherapy including CAM was performed for 55% of elderly patients and 73% of non-elderly patients. However, there were no significant differences in clinical efficacy rates or adverse reactions. Conclusions: Combined chemotherapy was performed for elderly patients with a good performance status (PS) and pulmonary NTM disease, achieving a favorable clinical effect equal in that of non-elderly patients. Therefore, it may be appropriate to actively perform diagnosis and treatment for elderly patients with pulmonary NTM disease showing a good PS.