Epidemiology and Impact of the HIV, NCD, and Urbanization Syndemic in Africa

非洲目前感染艾滋病毒的人数占世界的绝大多数（69%），有2600万人感染艾滋病毒

Africa bears the vast majority (69%) of the world’s current HIV infections with 26 million persons living with HIV (PLHIV). Increased access to antiretroviral therapy (ART) in Africa has markedly extended the lives of PLHIV and is shifting morbidity and mortality among PLHIV toward non-communicable diseases (NCDs), including high burden cardiopulmonary NCDs (CP-NCDs) such as congestive heart failure, hypertension, asthma, and chronic obstructive pulmonary disease. In addition, Africa is experiencing rapid urbanization with its associated increases in air pollution and changes in lifestyle and the social, structural, and health service environment. This remarkable convergence of HIV, CP-NCDs, and urbanization has profound implications for the future of global health. Unfortunately, there is a paucity of data on the impact of urbanization and air pollution on CP- NCDs and the potential role of HIV as an effect modifier, e.g. PLHIV may be more susceptible to urban ills due to existing chronic inflammation despite suppressed HIV viremia or from sequelae of past tuberculosis or other pulmonary infections. In addition, little is known about HIV and CP-NCDs health service utilization patterns as people migrate to urban settings and how HIV and CP-NCD care might be better integrated. Finally, HIV and CP-NCDs research in Africa has primarily been cross-sectional and often without HIV-negative comparison groups, major limitations in understanding causal factors and accurately calculating attributable fractions for traditional and non-traditional risk factors. Longitudinal, population-level approaches are needed to better guide future research, programs, and policies. The Rakai Community Cohort Study (RCCS), established in 1994, is an open, population-based cohort in 40 communities in south-central Uganda with survey rounds conducted over ~18 month intervals (RCCS census population ~33,000 adults, HIV prevalence ~18%). RCCS communities are non-urban; however, the cohort experiences an out-migration of ~950 participants per round to two large urban centers (Kampala and Masaka) where RCCS has satellite offices. With this unique research infrastructure, RCCS offers a novel opportunity to conduct longitudinal, population-based research on the HIV, CP-NCDs, and urbanization syndemic within a comprehensive health determinants framework. This study proposes to (i) Characterize HIV-related and -unrelated risk factors for cardiopulmonary non-communicable diseases in a novel Rural-to-Urban (R2U) African cohort; (ii) Characterize the impact of air pollution and moderating effects of HIV on cardiopulmonary outcomes among R2U migrants; and, (iii) Assess HIV and CP- NCDs health services utilization patterns among R2U migrants. To our knowledge, this would be the first population-based, longitudinal cohort study of the HIV, CP-NCDs, and urbanization syndemic in Africa. Our unique ability to leverage a rural-to-urban cohort, the excellent research infrastructure, and novel Aims will generate vital data needed for designing new research, interventions, and policies to combat the evolving HIV and CP-NCDs epidemic.