ABSTRACT
Dementia is the loss of cognitive function, a chronic, persistent, and progressively degenerative decline in brain function that negatively affects mental processes causing functional impairment. Alzheimer disease (AD) is the sixth leading cause of death in the United States and the fifth leading cause of death in people 65 years of age and older. Alzheimer's is the most common form of dementia. Most people diagnosed with dementia who are over the age of 65 have Alzheimer dementia. People whose onset of the disease occurs at age 65 or older are said to have late-onset AD. According to the Alzheimer's Association, the late-onset form of AD is marked by a gene called apolipoprotein E. Traumatic brain injuries may contribute to AD by disrupting normal brain function. There is no cure and no known prevention for AD. AD places an enormous emotional, physical, and financial stress on informal caregivers, including family members and friends.
