Year: 2026
Type: preprint
Study design: Observational Study
Abstract: INTRODUCTION Dementia research in sub-Saharan Africa remains limited despite rapid population aging and substantial ancestral, environmental, and vascular diversity. The Study of Ancestry, Health, Environment, and Late-Life Neurodegeneration (SAHEL) characterizes late-life cognitive decline and neurodegeneration in north-eastern Nigeria. METHODS SAHEL comprises community and hospital cohorts of adults aged 55 years or older in Yobe and Borno States. Participants undergo cognitive, functional, environmental, cardiovascular, metabolic, neuropsychiatric, and neurological assessments. Blood is collected for clinical profiling and biobanking, and consenting hospital participants provide skin biopsies for induced pluripotent stem cell generation. Planned analyses will integrate gut microbiota profiling, retinal imaging, and brain magnetic resonance imaging to investigate biological pathways and markers associated with healthy aging and cognitive outcomes. RESULTS From August 2025 through February 2026, 1,044 community participants were screened (mean age, 69.4 years; 56.4% female); 379 (36.3%) screened positive for cognitive concern and entered longitudinal follow-up. The hospital cohort enrolled 102 participants (mean age, 73.5 years; 57.8% male), including participants with Alzheimer’s disease, vascular dementia, mixed dementia, and mild cognitive impairment. Blood was collected from 809 community participants and all hospital participants. The cohort includes Kanuri, Fulani, Hausa, Babur/Bura, and Shuwa Arab participants. DISCUSSION SAHEL has established a large, deeply characterized aging and dementia research platform in north-eastern Nigeria. Its linked clinical, environmental, biomarker, genomic, imaging, microbiome, and cellular resources will enable investigation of population-specific risk and resilience mechanisms and strengthen dementia research and precision medicine in African populations.
Source: medRxiv
Authors: Suleiman Hamidu Kwairanga, Halima Jafiya Iwar, Amina Umar Faruk, Ibrahim Abdu Wakawa, Umar Baba Musami, Placidus Nwankuba Ogualili, Mohammed Yusuf Mahmood, Muhammad Abba Fugu, Mohammed Mala Gimba, Muktar Mohammed Allamin, Zaharadeen Umar Abbas, Muhammad Kawu Sunkani, Zainab Bukar Yaganami, Fatima Mustapha Kadau, Nasir Muhammad Sani, Peter Danmallam, Luka Emmanuel Nanjul, Larema Babazau, Zaid Muhammad, Dawoud Usman, Abdulrahman Idris Alkhamis, Baba Waru Goni, Babagana Kundi Machina, Cecilia S. Lee, Ibrahim Alkali Allamin, Adam Mustapha, Murtala Bindawa Isah, Salihu Joji, Olugbenga Oguntunde, Yaw Aniweh, Robert Lee Grossman, Takeshi Yoshimatsu, Udunna Anazodo, Chinedu Udeh-Momoh, Thomas K. Karikari, Celeste M. Karch, Chiadi U. Onyike, Mahmoud Bukar Maina
Institutions: Yobe State University, University of Maiduguri, University of Sussex, Washington University in St. Louis, University of Ghana, West African Centre for Cell Biology of Infectious Pathogens, University of Chicago, Montreal Neurological Institute and Hospital, Medical Artificial Intelligence Laboratory, McGill University, University of California, San Francisco, Karolinska Institutet, Aga Khan University Nairobi, Global Brain Health Institute, University of Sheffield, University of Pittsburgh, University of Pittsburgh Medical Center, Johns Hopkins University, Johns Hopkins Medicine, Newgate University Minna
Language: English
Subfield: Psychiatry and Mental health
Field: Medicine
Domain: Health Sciences
Open Access status: green
Funders: Alzheimer's Association, Wellcome Trust
Award: G2545128280
OpenAlex ID: W7214148741