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

Abstract

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. 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. 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. 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.