Jean Ikanga1,2 , Kharine Jean1 , Priscilla Medina3 , Saranya Sundaram Patel1,4 , Megan Schwinne5 , Emmanuel Epenge6 , Guy Gikelekele2 , Nathan Tshengele2 , Immaculee Kavugho7, Samuel Mampunza2, Lelo Mananga6, Charlotte E Teunissen8 , Anthony Stringer1 , Julio C Rojas9 , Brandon Chan9 , Argentina Lario Lago9 , Adam L Boxer9, Andreas Jeromin10, Bernard Hanseeuw11, Alden L Gross12 and Alvaro Alonso13

Abstract

Background: Hippocampal atrophy is a key feature of Alzheimer’s disease (AD), but neuroimaging is often inaccessible in low-resource settings. Blood-based biomarkers such as amyloid-β (Aβ42/40), phosphorylated tau-181 (p-tau181), neurofilament light (NfL), and glial fibrillary acidic protein (GFAP) may offer a practical alternative, though their utility in African populations remains understudied.
Objective: This study investigated the ability of plasma biomarkers of AD and AD-related dementias—Aβ42/40, p-tau181, NfL, and GFAP—to predict hippocampal atrophy in older adults in Kinshasa, Democratic Republic of Congo.
Methods: Eighty-five adults aged over 65 (40 healthy; 45 suspected AD) were recruited. Core AD (Aβ42/40, p-tau181) and non-specific (NfL, GFAP) biomarkers were analyzed. Hippocampal volumes were measured using MRI. Linear and logistic regressions assessed biomarker differences by age, sex, and neurological status, and predicted hippocampal atrophy.
Results: Elevated p-tau181 was associated with left hippocampal (LH) atrophy (p=0.020), with 4.2-fold increased odds [OR =4.2 (1.5–18.4)] of LH atrophy per standard deviation increase. The areas under the curve of plasma biomarkers without clinical covariates to discriminate LH, right hippocampal (RH), and total hippocampal (TH) atrophy ranged from 90%–94%, 76%–82%, and 85%–87%, respectively. Models including clinical covariates and biomarkers improved discrimination to 94%–96% (LH), 81%–84% (RH), and 88%–90% (TH).

Conclusions: Consistent with findings from other settings, core AD plasma biomarkers can effectively predict hippocampal atrophy in a Sub-Saharan African population, supporting their potential for scalable dementia screening where imaging is limited.
Keywords  Alzheimer’s disease, biomarkers, Congo, dementia Received: 3 September 2024; accepted: 6 June 2025

Journal of Alzheimer’s Disease
1–13
© The Author(s) 2025
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DOI: 10.1177/13872877251360697
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