Cognitive performance and plasma ADAM10 levels in low‐educated older adults with normal cognition, mild cognitive impairment, and Alzheimer’s disease

Abstract

AbstractBackgroundADAM10 has been investigated as a potential biomarker for Alzheimer’s disease (AD) (Monteiro et al., 2021). However, most of the production in the literature comes from high‐income countries, where the population usually has high educational attainment (Mukadam et al., 2019). Evidence in the literature suggests an effect of education on cognitive performance; thus, low‐educated older adults tend to have worse scores on cognitive tests. Also, low education has been associated with an increased risk of dementia (Mukadam et al., 2019; Suemoto et al., 2022). However, little evidence is available on plasma ADAM10 levels in a sample of older adults with low educational attainment.MethodParticipants were divided into three groups: Healthy (n = 33), MCI (n = 27), and AD (n = 30). Cognitive performance was assessed through MMSE and ACE‐R. SDS‐PAGE and Western‐Blotting were performed to obtain ADAM10 levels in plasma.ResultParticipants were primarily female (62.1%), the mean age was 74.5 (8.2), and the average years of education was 4.6 (4.3). Healthy participants performed better than the MCI group on MMSE (p = 0.04). Compared to the healthy participants, the AD group was older (p = 0.00); had more comorbidities (p = 0.02), was prescribed more medications (p = 0.00); had worse performance both on MMSE (p = 0.00) and on ACE‐R (p = 0.003); and had higher levels of plasma ADAM10 (p = 0.033). Significant differences between MCI and AD groups for age (p = 0.01), years of education (p = 0.008), medication use (p = 0.02), and MMSE score (p = 0.00) were observed. The logistic regression analysis indicated that having lower levels of plasma ADAM10 decreases the chances of an older adult having a diagnosis of AD by 82.3% (Exp(B) = 0.177; p = 0.005; 95%CI [0.053‐0.593]).ConclusionOur results suggested healthy low‐educated older adults had less plasma ADAM10 compared to individuals with AD. Also, despite low education, cognitive test scores differ for each group.