UCSF

Objective

We examined whether human mobility was associated with antiretroviral treatment adherence, measured via antiretroviral hair concentrations.

Design

This is a cross-sectional analysis of adults on antiretroviral treatment in East Africa at baseline in an observational cohort study.

Methods

Participants reported recent mobility (overnight travel) and histories of migration (changes of residence), including reasons, frequency/duration, and locations. Hair antiretroviral concentrations were analyzed using validated methods. We estimated associations between mobility and antiretroviral concentrations via linear regression adjusted for age, sex, region, years on treatment.

Results

Among 383 participants, half were women and the median age was 40. Among men, 25% reported recent work-related mobility, 30% nonwork mobility, and 11% migrated in the past year (mostly across district boundaries); among women, 6 and 57% reported work-related and nonwork mobility, respectively, and 8% recently migrated (mostly within district). Those reporting work-related trips 2 nights or less had 72% higher hair antiretroviral levels (P = 0.02) than those who did not travel for work; in contrast, nonwork mobility (any duration, vs. none) was associated with 24% lower levels (P = 0.06). Intra-district migrations were associated with 59% lower antiretroviral levels than nonmigrants (P = 0.003) while inter-district migrations were not (27% higher, P = 0.40).

Conclusion

We found that localized/intra-district migration and nonwork travel-more common among women-were associated with lower adherence, potentially reflecting care interruptions or staying with family/friends unaware of the participants' status. In contrast, short work-related trips-more common among men-were associated with higher adherence, perhaps reflecting higher income. Adherence interventions may require tailoring by sex and forms of mobility.