Non-tuberculous micobacteria in the elderly. Multicentric study.

Background: Nontuberculous mycobacterial (NTM) pulmonary disease is an increasingly common infectious condition that particularly affects patients with pre-existing lung disease, immunosuppression, and the elderly.

Objectives: To determine the incidence of NTM isolation and NTM pulmonary disease (NTM-PD) in older adults and describe their clinical, radiological characteristics, and treatment outcomes.

Methods: A multicenter observational study conducted retrospectively (2012-2017) and prospectively (2018-2020) in five tertiary hospitals in northern Spain. All adults aged ≥18 years with NTM isolation from respiratory samples were included and followed for two years.

Results: Among 594 patients, 220 (37 %) were aged >75 years. NTM-PD was confirmed in 192 cases, with 32 % occurring in elderly patients. The isolation rate was higher in older adults (13.8/100,000 vs. 2.94/100,000 in younger individuals), as was the disease rate (3.82/100,000 vs. 1.02/100,000). Older patients had fewer cavitated forms (27 vs 10 %), were less often diagnosed by bronchoscopy, and received proportionally less treatment despite meeting disease criteria. However, cure rates did not significantly differ between age groups.

Conclusions: Older adults exhibit a higher incidence of NTM isolation and disease but are managed with less aggressive diagnostic and therapeutic approaches, without compromising cure rates.