Pulmonary Tuberculosis in Older Adults: Increased Mortality Related to Tuberculosis Within Two Months of Treatment Initiation

Background The proportion of tuberculosis (TB) patients who are older adults is increasing worldwide. Nearly 60% of TB patients in Japan are 70 years or older, and the TB incidence rate in Japan is one of the highest among high-income countries. The previous TB treatment guidelines prior to 2018 in Japan recommended excluding pyrazinamide (PZA) from the initial regimen for patients aged over 80 years. Objectives We aimed to examine differences in TB treatment outcomes among different age groups, and between those who received PZA and those who did not. Methods We performed a retrospective cohort study of patients with pulmonary TB who were managed at a single medical center in Japan. We compared treatment outcomes and adverse events that resulted in treatment interruption across the age groups. Results Of 246 patients, 117 (48%) were aged 75 years or older. Compared with patients aged < 74 years, those ≥ 75 years were less likely to have PZA in the initial regimen (53.0% vs 89.9%; p < 0.0001), more likely to die during treatment (38.5% vs 6.2%; p < 0.0001), and more likely to experience adverse events (30.8% vs 19.4%; p < 0.05). The mortality rate related to TB at 2 months after TB treatment initiation was 28% in those aged ≥ 84 years. Furthermore, among patients aged ≥ 84 years, those who did not receive PZA were significantly more likely to die than those who did (65.8% vs 36.8%; p < 0.05). Conclusions Patients aged ≥ 75 years with pulmonary TB experienced increased mortality related to TB during treatment and more frequent adverse events than younger patients, even though PZA was often avoided among older patients.