Abstract
Timely initiation and sustained adherence to antiretroviral therapy (ART) are essential to improving the health outcomes of people living with HIV and preventing onward HIV transmission. However, women who use heroin often face challenges to initiating and adhering to ART. In this paper we identify spatial, temporal, and social factors that affect HIV treatment engagement among women who use heroin, drawing from a time geography framework. We conducted in-depth interviews with 30 heroin-using women living with HIV in Dar es Salaam, Tanzania between January and March 2019. We found that unstable housing, high mobility, HIV-related stigma, and unpredictable daily paths due to heroin use and involvement in sex work spatially and temporally constrained women who use heroin from incorporating HIV treatment behaviors into daily routines. Some women, however, were able to overcome these time-space constraints to HIV treatment engagement through social support and social role performance. Time geography, including concepts of time-space constraints and daily paths, is a useful framework for identifying barriers to ART engagement. Structural, relational, and individual interventions aimed at eliminating time-space constraints hold the potential to improve HIV treatment engagement among particularly vulnerable and mobile populations.