Supervisors info:
Σωκράτης Παπαγεωργίου, Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Ιωάννης Ζαλώνης, Αν. Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Κων/νος Πόταγας, Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Summary:
Alzheimer’s disease (AD) is the most common cause of dementia. Early-onset Alzheimer’s disease (EOAD) is a form of AD and is defined by onset of symptoms before the age of 65. Early-onset AD differs from typical late-onset Alzheimer’s disease (LOAD); is characterized by higher frequency of non-amnestic clinical subtypes. In the present study, primary object was to study the frequency of clinical subtypes in patients with early-onset Alzheimer’s disease. For this purpose, a group of patients with a diagnosis of AD and onset of symptoms before the age of 65 years was categorized into subgroups, which represent clinical subtypes, based on their predominant impairment on their performance on neuropsychological tests in five cognitive domains; verbal and visual memory, language, visuospatial functions, executive functions and apraxia. As a result, patients were divided into six groups; an amnestic subtype, a language subtype (logopenic variant of primary progressive aphasia - lvPPA), a visuospatial subtype (posterior cortical atrophy - PCA), a dysexecutive syndrome (dysexecutive variant of frontal variant of AD), a subtype with apraxia as prominent deficit and a multidomain cognitive syndrome. The most frequent subtype was the multidomain cognitive syndrome, followed by apraxic subtype, visuospatial subtype (PCA), dysexecutive subtype, amnestic subtype and the least frequent subtype was the language subtype (lvPPA). From statistical analysis, there were significant differences between these clinical subtypes in all cognitive domains, except memory and language. Non-amnestic subtypes had higher frequency than typical amnestic subtype, which represented a minority of patients. Thus, heterogeneity in cognitive domains, in patients with early-onset AD is common. As a result, it is important to mention that early-onset AD is associated with delay in diagnosis and misdiagnosis. In conclusion, there is a need to pay more attention in this disease and to study the neuropsycological profile of its clinical subtypes.
Keywords:
Alzheimer's disease, Early onset Alzheimer’s disease, Clinical subtypes, Frequency, Non-amnestic subtypes
