Characteristics of the Clinical and Neuroimaging Picture in Patients with Early-Onset Alzheimer’s Disease

The most common cause of severe cognitive impairment in adults is Alzheimer’s disease (AD). Depending on the age of onset, AD is divided into early (<65 years) and late (≥65 years) forms. Early-onset AD (EOAD) is significantly less common than late-onset AD, accounting for only about 5–10% of cases. However, its medical and social significance as a disease leading to loss of ability to work and legal capacity, as well as premature death in patients aged 40–64 years, is extremely high. Patients with EOAD, as compared with late-onset AD (LOAD), have a greater number of atypical clinical variants: 25% and 6–12.5%, respectively, which complicates the differential diagnosis of EOAD against other neurodegenerative diseases. Nonetheless, the typical amnestic variant predominates in both LOAD and EOAD. Also, patients with EOAD have characteristic neuroimaging features: brain MRI scans from patients with EOAD often have more severe parietal atrophy and less severe hippocampal atrophy than those from patients with LOAD. This report addresses the features of the clinical and neuroimaging picture in patients with EOAD. A clinical case of a patient with EOAD is presented.