Zambian Cohort of Healthy Aging and Dementia (ZCHAD) Study

About This Grant

Project Abstract Alzheimer’s Disease and Alzheimer’s Disease-Related Dementias (AD/ADRD) affect 51 million people worldwide, a prevalence expected to triple by 2050. Two-thirds of those with AD/ADRD live in low- and middle- income countries (LMICs) where the greatest growth in AD/ADRD prevalence is expected, but where services to diagnose and manage this condition are scarce and data regarding dementia burden are limited. Although the Lancet Commission on Dementia, Prevention, Intervention, and Care has identified 14 modifiable risk factors that contribute to 45% of AD/ADRD cases worldwide, there are limited data regarding the prevalence and role of these modifiable risk factors in LMICs. Thus, interventions targeting these factors may have limited impact on AD/ADRD risk in LMIC settings. This proposal’s overall objective is to assess the prevalence rate of AD/ADRD and associated risk factors among adults age ≥55 years in urban and rural Zambia, a LMIC in sub- Saharan Africa. Based on our pilot work, we hypothesize that the prevalence rate of AD/ADRD among adults age ≥55 years will be approximately 9.5% and prevalence of associated risk factors will differ between urban and rural participants. These hypotheses will be tested through a population-based study of adults age ≥55 years in the urban Lusaka and rural Mazabuka Districts of Zambia. AD/ADRD prevalence will be assessed using formal neuropsychological testing, participant, and informant report according to DSM-V criteria. Additional validated questionnaires, a physical examination, and laboratory investigations will assess AD/ADRD risk factors. This project will also build and expand the neuropsychiatric expertise and workforce necessary to conduct prospective AD/ADRD research by providing training and AD/ADRD research experience for a Zambian neuropsychologist, neuropsychologists-in-training, and a cohort of community health workers. The proposed research is highly innovative because it examines AD/ADRD prevalence in a population with limited existing data and expected growth in rates of AD/ADRD and associated risk factors. Knowledge gained from this work will determine (1) the prevalence of AD/ADRD and (2) the prevalence of modifiable risk factors which have the greatest impact on AD/ADRD prevalence in this rapidly aging population. This project will have a significant impact by expanding the capacity for AD/ADRD studies in Zambia and will lay the groundwork for the conduct of future longitudinal studies and trials assessing low-cost interventions to reduce AD/ADRD prevalence and improve patient care.