Bridging the Diversity Gap: Why Alzheimer’s Research in Africa Matters
Many countries in Africa have genetically diverse populations that are rapidly aging. Despite this, Alzheimer’s remains understudied there — but researchers are working to change that.
Populations across many African nations have more genetic variation than any other populations in the world. Scientists already know of certain genetic risk factors for diseases like Alzheimer’s (like ApoE4, the strongest genetic Alzheimer’s risk factor so far identified). But there may be many other, as-yet-undiscovered genes that shape a person’s risk for disease — and Alzheimer’s scientists in particular think that better studying Africa’s diverse populations could be key to finding them.
But leading African researchers say there are still “vast gaps in knowledge” about Alzheimer’s on the continent.
It’s urgent to fill those gaps: In addition to its genetic diversity, Africa has one of the world’s fastest-aging populations. The number of people in Africa with Alzheimer’s disease is growing rapidly. In 2015, 2.13 million people in Sub-Saharan Africa had the disease, and Alzheimer’s Disease International projects it will see almost 3.5 million cases of Alzheimer’s by 2030.
Even still, experts say researchers and drug companies have largely ignored this population when it comes to studying Alzheimer’s here or testing new treatments in African populations. As of June 2025, there were no Alzheimer’s disease clinical trials recruiting participants in Africa. More than 3,400 Alzheimer’s trials have been conducted worldwide. A 2023 Politico analysis found that only 60 trials have ever included African patients — and 90 percent took place in just five of Africa’s 54 countries: South Africa, Egypt, Morocco, Tunisia, and Uganda.
Why is Africa — and all it could have to teach scientists — being left in the dark when it comes to Alzheimer’s research?
“The reason there are no trials in Africa is a lack of infrastructure to run long trials,” Vaibhav Narayan, executive vice president for strategy and innovation at the Davos Alzheimer’s Collaborative, told Being Patient. “They require clinical diagnoses. They require expensive infrastructure like PET scans or MRIs, and some of this infrastructure is not available in Africa.”
The Davos Alzheimer’s Collaborative is focused on accelerating dementia research by building global collaborations to change that.
Many scientific advances have been made that can slow cognitive decline in Alzheimer’s, but most participants in these studies have been white and from high-income countries like the U.S. Because of this, there are concerns that new diagnostics and treatments, including blood tests and anti-amyloid drugs, may be less effective for non-white populations. Researchers say the key to developing better tools and treatments is to study more diverse groups of people to better understand the genetics of Alzheimer’s.
By including African study populations, researchers can better understand how genetics, environmental exposures, and co-occurring health conditions — like cardiovascular disease — interact to affect dementia risk.
“Studying the disease in people with different genetic backgrounds, different environmental risk factors, different co-morbidities that were not controlled in their mid-life, gives a fuller picture of how this disease develops and progresses, and can lead to more targeted solutions,” Narayan said.
Dr. Mohamed Salama, a neurologist at the American University in Cairo, is leading the Egyptian Longitudinal Study of Aging in partnership with DAC to track these factors in 20,000 adults over 50 as they age. Since Salama and his team will spot risk factors before the disease starts, it also gives them the “luxury of early intervention” and may allow them to test out new prevention strategies.
Overcoming research barriers
For Salama, one of the challenges is putting dementia on the public health agenda. Low- and middle-income countries are often balancing many different health problems, from infectious diseases to building infrastructure. Policymakers want more evidence before prioritizing dementia funding. Projects like the Egyptian aging study aim to provide that evidence.
Salama added that compared to Western countries, awareness of dementia is lower in many African regions, and cognitive decline is often considered a normal part of aging. “People think that it is normal to have cognitive decline when you are growing old,” said Salama. “You are supposed to grow old — but cognitively healthy.”
Cultural differences also affect how dementia is understood. In some regions, there isn’t a specific word for dementia. In parts of Zambia, for example, people with the disease may face stigma, including accusations of witchcraft. To address these challenges, DAC began work in Kenya within the community to understand the best way to run the study.
“We call it the ‘Living Lab’ approach, where you make sure that the community is fully involved in the design of the protocol, and we get their input up front,” Narayan explained.
Adapting diagnostic tools in African populations
Many common Alzheimer’s diagnostic tools in higher-income countries — like amyloid PET scans and lumbar punctures — are expensive and require infrastructure that may be lacking in many African settings. DAC and its partners, including Aga Khan University in Kenya and the American University in Cairo, rely instead on more affordable methods like voice recordings, smell tests, and retinal scans. These can be collected even in remote areas without advanced medical equipment.
DAC has also supported local initiatives like the North African Dementia Registry, which collects bio-samples, cognitive assessments, and digital biomarkers (such as speech and smell) to better understand dementia risk. While much of this work so far has been in Kenya and Egypt, researchers hope to expand across the continent.
According to Salama, who helps lead the registry, the key is making sure that the data collected from one population can be compared to another. His team has been validating and adapting cognitive assessments across different languages and cultural contexts so that data is comparable across regions.
From bio-samples to treatments
Alzheimer’s drugs are only effective when people can access them — and treatments need to be scalable globally.
Narayan explained that the Davos Alzheimer’s Collaborative is promoting research to push these kinds of low-cost drugs forward: “They are oral, small molecules and they don’t require very expensive PET scans and monitoring.”
This could be more feasible than infusions of anti-amyloid drugs like Leqembi or Kisunla, which require specialized infusion centers and expensive monitoring for side effects such as brain swelling.
Instead, researchers are investigating whether targeting risk factors such as diabetes, insulin resistance, and vascular disease could help prevent or delay dementia. That opens the possibility of repurposing existing drugs, like metformin or semaglutide, as potential treatments.
If genetic variants identified in African cohorts lead to new therapies, researchers stress that drug companies must also ensure these treatments are accessible and affordable in the regions where the discoveries were made.
“It makes no sense to conduct [drug] research in Europe, and try to apply the drugs developed based on this research in Africa,” said Salama. Drug companies not only need to invest more in African countries, he said, but they must make sure that drugs that are developed based on research there will remain affordable.
Expanding Alzheimer’s research in Africa could help improve care locally: Narayan believes that studying a genetically diverse population could help scientists better understand the biology of Alzheimer’s and how it interacts with the environment… and this understanding could lead to treatments that benefit people everywhere.
