Associations between Extreme Weather Events, Mobility, and Resource Insecurities with HIV Vulnerabilities Among Older Adults In Moshi, Tanzania

Background and Purpose: Extreme weather events affect HIV vulnerabilities through the interplay of complex pathways in Sub-Saharan Africa, yet limited evidence includes older adults. These pathways connecting extreme weather event exposure to HIV prevention and care outcomes may be understood through an ecosocial approach that considers social hazards, such as poverty, and environmental hazards, including extreme weather events and related mobility. We examined associations between extreme weather event exposure, recent weather and seasonal-related mobility, and resource insecurities, with HIV vulnerabilities among older adults in Moshi, Tanzania.

Methods: We conducted a community-based cross-sectional survey in Moshi with adults aged >50 randomly sampled from the Prospective Urban Rural Epidemiology (PURE) cohort. We conducted multivariable regression analyses to examine associations between ecosocial exposures (past-year extreme weather event exposure; past month and 6-month seasonal/weather-related mobility; food, water, and/or sanitation insecurity) and HIV vulnerabilities (condom use self-efficacy; sexual relationship power; lifetime intimate partner violence). We also examined protective factors including resilience and social support. Models were adjusted for age, gender, education, and relationship status.

Results: Among participants (n=250; mean age: 60.6 years, standard deviation [SD]=11.1; 72.8% cisgender women), most (56.0%) reported multiple past year extreme weather event exposure. One-third (33.9%) reported low food security, and 28.9% very low food security. The majority (94.0%) reported water security. Nearly one-fifth reported recent seasonal or weather-related mobility, with 14.8% reporting past 6-month travel and 3.6% past month travel. In multivariable analyses, past-year extreme weather event exposure (1 extreme weather event vs. none) (adjusted beta [aβ]= -1.09, 95% Confidence Interval [CI]: -2.08 to -0.10), past 1-month seasonal/weather-related mobility (aβ=-2.25, 95%CI: -3.45 to -1.06), past 6-month seasonal/weather-related mobility (aβ=-1.83, 95%CI: -3.17 to -0.48), and low food security (vs. high/marginal) (aβ=-0.94, 95%CI: -1.72 to -0.15) were associated with lower condom use self-efficacy, while higher social support (aβ=0.11, 95%CI: 0.06- 0.16) and resilience (aβ=0.28, 95%CI: 0.12-0.44) were associated with increased condom use self-efficacy. Past one-month (aβ=-5.03, 95%CI: -7.04 to -3.02) and six-month (aβ=- 2.59, 95% CI: -4.72 to -0.48) seasonal/weather-related mobility were associated with lower sexual relationship power. Past one-month seasonal/weather-related mobility (adjusted odds ratio [aOR]=12.31, 95% CI: 2.67–56.80) and sanitation insecurity (aOR=1.20, 95% CI: 1.10–1.32) were associated with higher intimate partner violence odds.

Conclusions: Exposure to multiple past-year extreme weather events, recent mobility related to weather or season, and resource insecurity (i.e., food, water, sanitation) were associated with a range of relational-level HIV vulnerabilities, including lower condom use self-efficacy, reduced sexual relationship power, and a higher likelihood of lifetime IPV among older adults in Moshi, Tanzania. Findings signal the importance of including older adults in HIV and climate change related research—where they are often overlooked—and the relevance of an ecosocial approach that considers the role of social and environmental hazards in shaping older adults’ HIV vulnerabilities. Findings underscore the need to integrate violence prevention and multiple material needs support within climate-responsive HIV prevention programs that meaningfully include older climate-affected populations. Future research can further explore HIV prevention opportunities with mobile older populations in climate-affected settings such as Tanzania.