Early detection and diagnosis of dementia

Early detection and differential diagnosis of dementia are essential for choosing proper therapies aimed at removing the causes of reversible dementias or adequately treating cognitive and behavioral symptoms of progressive dementias such as Alzheimer's disease (AD). The most difficult aspect in the detection of mental deterioration is to discriminate normal aging from the early stage of dementia or from depression. The current criteria for the formal diagnosis of AD require that the disease is well-established. However, several recent studies demonstrated that early diagnostic markers of AD can be detected many years before these criteria are satisfied. Low linguistic abilities and selective impairment of episodic memory, especially verbal memory, have been found to be preclinical markers for the development of AD. A successful approach to the early detection of AD should consider the typical and atypical presentations of the disease. Finally, the recognition of qualitative differences in cognitive impairment of patients with AD and patients with other types of dementia is crucial as early as possible, to establish clinical differential diagnosis between degenerative dementias.