Mortality association of nontuberculous mycobacterial infection requiring treatment in Taiwan: a population-based...

Infection due to nontuberculous mycobacteria (NTM) is an emerging issue worldwide, and we aimed to address the epidemiology and mortality association of NTM infection requiring treatment in Taiwan.

We used the 2003-2018 data of 2 million representative individuals in Taiwan's National Health Insurance Research Database. We identified patients with newly diagnosed NTM infection and received treatment as NTM cases. Age- and sex-matched (1:40) as well as propensity score-matched (PSM) (1:2) non-NTM individuals were selected as non-NTM controls. We used a Cox proportional hazard model to determine hazard ratios (HRs) with 95% confidence intervals (CIs).

We identified 558 patients with NTM infection requiring treatment. The mean age was 62.5 ± 15.4 years, and 57.5% of them were male. The incidence increased from 0.54 per 100,000 person-year in 2003 to 3.35 per 100,000 person-year in 2018. The overall mortality was 35.2%, with a mean follow-up duration of 4.1 ± 3.6 years. We found that NTM infection was independently associated with a greater risk of mortality (HR: 1.71; 95% CI: 1.47-1.98) compared with age- and sex-matched controls, and the association remained consistent (HR: 1.44; 95% CI: 1.19-1.75) compared with propensity-matched controls. We also found that old age, male, high Charlson comorbidity index, and the use of steroids or anti-neoplastic agents/immunosuppressants were associated with mortality risk.

In conclusion, we found a steady increase in patients with NTM infection requiring treatment in Taiwan and further demonstrated that NTM infection was associated with greater risk of mortality using two comparable non-NTM control subjects.