Adherence trajectory as an on-treatment risk indicator among drug-resistant TB patients in the Philippines.

INTRODUCTION: High levels of treatment adherence are critical for achieving optimal treatment outcomes among patients with tuberculosis (TB), especially for drug-resistant TB (DR TB). Current tools for identifying high-risk non-adherence are insufficient. Here, we apply trajectory analysis to characterize adherence behavior early in DR TB treatment and assess whether these patterns predict treatment outcomes. METHODS: We conducted a retrospective analysis of Philippines DR TB patients treated between 2013 and 2016. To identify unique patterns of adherence, we performed group-based trajectory modelling on adherence to the first 12 weeks of treatment. We estimated the association of adherence trajectory group with six-month and final treatment outcomes using univariable and multivariable logistic regression. We also estimated and compared the predictive accuracy of adherence trajectory group and a binary adherence threshold for treatment outcomes. RESULTS: Of 596 patients, 302 (50.7%) had multidrug resistant TB, 11 (1.8%) extremely drug-resistant (XDR) TB, and 283 (47.5%) pre-XDR TB. We identified three distinct adherence trajectories during the first 12 weeks of treatment: a high adherence group (n = 483), a moderate adherence group (n = 93) and a low adherence group (n = 20). Similar patterns were identified at 4 and 8 weeks. Being in the 12-week moderate or low adherence group was associated with unfavorable six-month (adjusted OR [aOR] 3.42, 95% CI 1.90-6.12) and final (aOR 2.71, 95% 1.73-4.30) treatment outcomes. Adherence trajectory group performed similarly to a binary threshold classification for the prediction of final treatment outcomes (65.9% vs. 65.4% correctly classified), but was more accurate for prediction of six-month treatment outcomes (79.4% vs. 60.0% correctly classified). CONCLUSIONS: Adherence patterns are strongly predictive of DR TB treatment outcomes. Trajectory-based analyses represent an exciting avenue of research into TB patient adherence behavior seeking to inform interventions which rapidly identify and support patients with high-risk adherence patterns.

Impact of shelter-in-place orders on TB case notifications and mortality in the Philippines during the COVID-19 pandemic.

BACKGROUND: Policies implemented to slow transmission of COVID-19 are expected to have disrupted delivery of routine health services, including tuberculosis (TB) care. METHODS: We analyzed daily counts of drug-susceptible (DS)-TB case notifications from all health facilities affiliated with the Philippines National TB Program (NTP) before and after implementation of community quarantine (January 1-December 31, 2020). Using an interrupted time series design, we assessed the immediate and sustained effects of community quarantine on TB case reporting. Using 2019 WHO estimates of national TB incidence, treatment, and mortality rates for the Philippines, we modeled excess mortality from TB, assuming a national decline in TB case reporting were extended for 12 months, followed by a return to pre-community quarantine trends. RESULTS: The analysis included 192,918 DS-TB case notifications from 2,986 facilities located in 113 provinces and highly urbanized cities across 17 regions and covered 49 observations days before and 174 days after community quarantine implementation. We found an significant drop and steeper decline in daily TB case notifications after the implementation of community quarantine, resulting in 44.6% (95% CI 38.3-50.1) fewer daily TB case notifications 60 days after implementation of community quarantine. During 2020, DS-TB case notifications never returned to pre-quarantine levels. Assuming a 12-month disruption of TB case reporting, we estimate there will be 56.3% increase in TB-related deaths in the Philippines. CONCLUSION: Modified delivery of TB prevention and care should be prioritized alongside efforts to combat COVID-19.