"Now that I took TPT, it's affecting my ART adherence, viral load, even my wellbeing in the community". Exploring acceptability and experience of Tuberculosis Preventive Treatment among adolescents living with HIV in Zimbabwe.

Tuberculosis preventive treatment (TPT) is increasingly offered to people living with HIV in high-burden settings, including adolescents and young people (AYPLHIV). Evidence demonstrates that AYPLHIVs' HIV treatment engagement is improved by the provision of tailored support. How to effectively adapt this support to accommodate multimorbidity care, such as TPT alongside ART, warrants attention to deliver sustained optimal outcomes. We conducted qualitative research to better understand AYPLHIVs' experiences when initiating TPT and their related support needs. Peer counsellors (18-24 years) who were offered TPT within routine HIV care participated in two focus groups (n = 16 participants) and in-depth interviews (n = 12) in Harare. Iterative data collection and thematic analysis was conducted September 2023 to February 2024. TPT was presented by healthcare workers as uncomplicated and routine. This contrasted with participants' accounts of the significant disruptive and challenging experience of taking up TPT. This tension led many to stop TPT without support. Those who completed treatment were motivated by personal circumstances (e.g., recently witnessing severe TB illness, pregnancy); however, taking up and completing subsequent courses of TPT was not assured. TPT side effects and stigma led many to discontinue treatment, even when these were not personally experienced. Side effects recalled past experiences of HIV-stigma and discrimination, and undermined ART adherence, HIV viral suppression, and positive mental health. Introducing additional life-protecting treatments can have complicating biosocial effects, with consequences for individuals and public health. To support multimorbidity prevention and care, we outline five principles to guide initiating and maintaining treatment that acknowledges and responds to AYPLHIVs' dynamic immunological and social realities: Supported and safe relationships; Tailored messaging; Adaptable support; Respect for agency and autonomy; Timing: plan, review, revise (START). START emphasises investing in consistent peer support throughout adolescence, and centring AYPLHIVs' agency, embodied knowledge and wellbeing to ensure they are informed decision-makers about their health.