High levels of recurrent TB in the Philippines: results from a rural community cohort using a pragmatic design

BACKGROUND TB remains a major public health problem in the Philippines, which is among the 30 highest TB-burden countries. While treatment success rates are often used as indicators of programme performance, recurrence rates provide a more objective measure of long-term treatment effectiveness. Currently, the Philippines has limited data on recurrent TB. METHODS This cohort from an active TB surveillance study in San Juan, Batangas (2013–2015), was followed up from March 2018 to January 2022. Recurrent TB, defined as an active TB case diagnosed and treated before with anti-TB drugs, was identified using national guidelines. Socio-demographic and clinical data were obtained from interviews and medical records. Incidence rates (per 1,000 person-years) and factors associated with recurrence were analysed using Cox proportional hazards models. RESULTS A total of 284 individuals were followed up for a median of 7.1 years, during which 71 participants (25%) developed recurrent TB, corresponding to an incidence rate of 38.3 cases per 1,000 person-years. Most recurrent cases were clinically diagnosed (87%) and occurred more than 2 years after the initial episode. Older age and lower socio-economic status were significantly associated with recurrence ( P < 0.01). CONCLUSION Using pragmatic study design, we found TB recurrence is common in this high-burden setting.