Plasma ADAM10 Levels and Their Association with Alzheimer’s Disease Diagnosis in Older Adults with Fewer Years of Formal Education

Abstract

<b><i>Introduction:</i></b> Low educational attainment is a potential risk factor for Alzheimer’s disease (AD) development. Alpha-secretase ADAM10 plays a central role in AD pathology, attenuating the formation of beta-amyloid peptides and, therefore, their aggregation into senile plaques. This study seeks to investigate ADAM10 as a blood-based biomarker in mild cognitive impairment (MCI) and AD in a diverse group of community-dwelling older adults, focusing on those with limited educational attainment. <b><i>Methods:</i></b> Participants were recruited from public health services. Cognition was evaluated using Mini-Mental State Examination (MMSE) and Addenbrooke’s Cognitive Examination – Revised (ACE-R) batteries. Blood samples were collected to analyze plasma ADAM10 levels. A logistic regression was conducted to verify the influence of plasma ADAM10 on the AD diagnosis. <b><i>Results:</i></b> Significant differences in age, years of education, prescribed medications, and cognitive test scores were found between the MCI and AD groups. Regarding cognitive performance, both ACE-R and MMSE scores displayed significant differences between groups, with post hoc analyses highlighting these distinctions, particularly between AD and cognitively unimpaired individuals. Elevated plasma ADAM10 levels were associated with a 4.5-fold increase in the likelihood of a diagnosis of MCI and a 5.9-fold increase in the likelihood of a diagnosis of AD. These findings suggest ADAM10 levels in plasma as a valuable biomarker for assessing cognitive status in older individuals with low education attainment. <b><i>Conclusion:</i></b> This study underscores the potential utility of plasma ADAM10 levels as a blood-based biomarker for cognitive status, especially in individuals with low educational backgrounds, shedding light on their relevance in AD development and diagnosis.