Implementation of enhanced 99DOTS for TB treatment supervision in Uganda: An interrupted time series analysis

Abstract

Rationale: Digital adherence technologies are being scaled-up for tuberculosis treatment despite limited evidence of their effectiveness and concerns about accessibility. Objectives: To determine whether an enhanced 99DOTS-based treatment supervision improves uptake of 99DOTS and tuberculosis treatment outcomes. Methods: We included all adults initiated on treatment for drug-suceptible pulmonary tuberculosis between August 2019 and June 2021 at 18 99DOTS-experienced health (n=6,382) facilities and 12 99DOTS-naive health facilities (n=4,253) in Uganda. Using an interrupted time series design, we compared the proportions with treatment success (primary outcome) and enrolled on 99DOTS in the 9 months before and the 12 months after implementing an 'enhanced 99DOTS' intervention that included components to increase uptake (providing low-cost phones to people with TB when needed) and enhance treatment monitoring and support (task shifting to community health workers and automated task lists). Data on treatment initiation and outcomes were derived from routine TB treatment registers. Measurements and Main Results: At 99DOTS-experienced facilities, the proportion enrolled on 99DOTS increased from 49.2% to 86.4%. The proportion completing treatment remained similar across periods (78.3% vs. 78.6%). There was no immediate level change in treatment success following the intervention but there was a significant change in monthly slope (proportion ratio 1.01, 95% CI 1.00-1.02), reflecting an improved treatment success trend following the intervention. Results were similar at 99DOTS-naive facilities, except there was no significant change in treatment success slope. Conclusions: Enhanced 99DOTS had high uptake and did not negatively affect treatment outcomes. Equity in access should be prioritized during implementation.