Education as a domain-specific moderator: Shaping the impact of cerebral structural changes on clinical manifestations in Alzheimer's disease

Background Global cognitive performance is influenced by change in cerebral structure and educational background. However, little is known about how education moderates the impact of cerebral structural changes on different cognitive domains and other non-cognitive dysfunction across the clinical stages of Alzheimer's disease (AD). Objective To explore the moderating effect of education on relationship between cerebral structure and various clinical manifestations across the AD continuum, ranging from mild cognitive impairment (MCI) to AD. Methods This cross-sectional study included data of 570 patients diagnosed with MCI or AD. The total years of education were used as a moderating variable, and AD-related cerebral structure changes were assessed through visual ratings on magnetic resonance imaging (MRI). Multiple linear regressions were performed to examine whether education moderated the association between cerebral structure and clinical characteristics at different diagnostic stages of AD. Results Patients with higher levels of education demonstrated better cognitive ability, enhanced activities of daily living, and milder neuropsychiatric symptoms. The moderating effect of education was most prominent during the MCI or early AD stages, showing cognitive domain-specific effects. In these stage, education alleviated the negative impacts of neurostructural changes on immediate learning but exacerbated the detrimental effects of cerebral structural changes on speed/executive function, language, and episodic memory. Conclusions Education serve as a moderator in relationship between cerebral structure and various clinical characteristics. The moderating effect of education is domain-specific and most noticeable in the early stage of AD.