Patients with Alzheimer disease most commonly present with insidiously progressive memory loss, to which other spheres of cognitive impairment are added over several years. After memory loss occurs, patients may also have language disorders (eg, anomia) and impairment in their visuospatial skills and executive functions.
The cause of Alzheimer disease is unknown. Several investigators now believe that converging risk factors, which include advancing age, lipoprotein E epsilon 4 genotype, obesity, insulin resistance, vascular factors, dyslipidemia, hypertension, and inflammatory markers trigger a pathophysiologic cascade that, over decades, leads to Alzheimer pathology and dementia.
Alzheimer disease affects both men and women; however, Plassman et al found the risk of developing Alzheimer disease to be significantly higher in women than in men, primarily due to the higher life expectancy in women compared with men.
Alzheimer disease is most prevalent in individuals older than 60 years. Some forms of familial early-onset Alzheimer disease can appear as early as the third decade, but this represents a subgroup of the less than 10% of all familial cases of Alzheimer disease.More than 90% of cases of Alzheimer disease are sporadic and occur in individuals older than 60 years.
Of interest, results of some studies of nonagenarians and centenarians suggest that the risk may decrease in individuals older than 90 years. If so, age is not an unqualified risk factor for the disease, but further study of this matter is needed...
tags:Alzheimer,Alzheimer disease , 60 years. ,the less than. Alzheimer disease is unknown,