PROJECT SUMMARY Epidemiologic models have predicted that by 2040, 27% of the population living with HIV in sub-Saharan Africa (SSA) will be 50 years of age or older; however, these models appear to underestimate both the timing and magnitude of the age shift. As of 2022, 21% of all people on antiretroviral therapy (ART) in countries supported by the President's Emergency Plan for AIDS Relief are 50 years of age and older. As the HIV epidemic in SSA comes under control—with more people living with HIV (PLWH) diagnosed, placed on ART, and achieving viral suppression—updated models are needed to more accurately predict and plan for coming demands on the HIV-related healthcare system. The burden of HIV-associated noncommunicable diseases (NCD) is well documented, and risk rises markedly with age. With increases in life expectancy among PLWH, healthcare resource limitations, increased focus on integrating NCD management into HIV platforms, and the imperative to achieve and sustain HIV control in all subpopulations, models that accurately capture and predict the age distribution and NCD burden of PLWH are critical to address knowledge gaps and support precision program implementation. We posit that countries in SSA with high HIV burden will experience the shift in the age distribution to greater than 50% of PLWH over the age of 50 at least a decade sooner than predicted by more commonly used models. Botswana and Zambia are two settings with different epidemic characteristics, providing a unique opportunity to develop and test a new demographic prediction model for more accurate prediction of this “silver tsunami” in PLWH and NCD burden. The goal of this study is to use repeated nationally representative data from Botswana and Zambia to develop a cohort model with age-stratified transmission risk that predicts the age distribution and NCD burden among PLWH through 2050. The proposed Epidemiologic Predictions to Inform Programs for Long-term Aging Needs among people living with HIV (EPI-PLAN HIV) project will generate a framework for accurate prediction of both the age shift and NCD risk in aging populations of PLWH through the following aims 1) Characterize sexual networks in Botswana and Zambia using repeated HIV population-based survey data, 2) Build a cohort model with age- stratified HIV transmission risk to predict the age distribution among PLWH over time, and 3) Predict the burden of NCD among PLWH in Botswana and Zambia over time. The outcomes of this project will be used to accelerate the health system's response and serve as the foundation for future research into the growing burden of NCD in PLWH in SSA.