Brain-Derived pTau217 and Plasma Proteomic Profiles Across Cognitive and Dementia Groups in Congolese Older Adults

In 786 Congolese adults aged 65+ in Kinshasa, plasma MME is downregulated across all dementia groups, with the largest effect in each dementia versus cognitively unimpaired comparison.

• Why it matters: Blood biomarkers for Alzheimer disease and related dementias are validated mainly in European-ancestry populations, leaving uncertainty about performance and protein signals in Congolese older adults.
• What they did: Plasma proteins were quantified using the NULISAseq CNS Disease Panel 120 in cognitively unimpaired, mild cognitive impairment, suspected Alzheimer disease, mixed dementia, and vascular dementia groups; a random forest used 10 biomarkers plus age, sex, and APOE ε4 status.
• The result: The random forest achieved mean cross-validated AUC 0.768 versus 0.612 for brain-derived pTau217 alone, and the full-dataset ranking step may make performance optimistic.