Biomarkers

Plasma biomarkers as well as non-invasive measures of frailty are increasingly employed to aid population-wide cognitive screening, phenotyping and preclinical diagnosis. Hand grip strength (HGS), a measure of physical and cardiometabolic health, is indicative of early cognitive decline but its relationship with plasma biomarkers of Alzheimer's Disease (AD) and neurodegeneration is not known. We investigated the association between HGS and plasma markers of AD and neurodegeneration in the Vascular heAlth, fraiLty, and cognItion in Ageing Nigerians (VALIANT) study.

VALIANT is a longitudinal community-based cohort study. One thousand and thirty-six (1036) participants were recruited from Wards 2 and 3 of the Ibadan Northeast local government area of Oyo State, Nigeria through a multi-stage, stratified cluster random sampling method. Initial screening for cognitive dysfunction was performed using the IDEA, and MoCA scores. Patients were then diagnosed as having dementia and MCI via a consensus diagnosis of at least two neurologists. Glial fibrillary acidic protein (GFAP), neurofilament light chain (NfL), phosphorylated tau (p-tau)217 and amyloid beta (Aβ)42/40 were measured using ultra-sensitive immunoassays. Biomarker data were log- and square-root transformed. Multiple linear regression analysis was employed to detect the relationship between HGS and plasma biomarkers, while adjusting for sociodemographic, lifestyle, cardiometabolic, social and cognitive function scores. β coefficient and corresponding 95% CI was reported. (p-value <0.05) RESULT: At baseline, a total of 35 participants (3.4%) and 112 (11%) had dementia and mild cognitive impairment (MCI) respectively. The mean (SD) age of participants was 77.0 (11.3) dementia, 72.6 (9.8) MCI and 63.8 (9.9) normal (p value<0.001). In the simple linear regression, significant bivariate relationship was observed between HGS and all the plasma biomarkers. In the multiple linear regression analysis, HGS showed an independent relationship with respective β (95% CI) of -0.0026 (-0.0051, -0.0001) for pTau217, 0.009 (0.002, 0.016) for Ab42, and -0.013 (-0.021, -0.004) for NfL.

Hand grip strength is independently associated with plasma markers of neurodegeneration in this cohort of community-dwelling older Nigerians individuals. Both measures could serve as potential screening tools for identifying individuals at risk for AD/ADRD, complementing other existing biomarkers.