Dementia is not a specific disease; it is a collection of symptoms that can be caused by a number of disorders, including neurodegenerative disease. The term "dementia" describes a progressive decline in memory or other cognitive functions that interferes in the ability to perform your usual daily activities (driving, shopping, balancing a checkbook, working, communicating, etc.). The deterioration is more than might be expected from normal aging and is due to damage or disease. While dementia often includes memory loss, memory loss by itself does not mean that you have dementia.
Approximately 3.4 million individuals aged 71 and older in the United States have dementia (reference), and an estimated 5.3 million Americans of all ages have Alzheimer’s disease (reference). While a number of different diseases can cause dementia, Alzheimer's disease is the most common cause in older adults. Some other diseases that cause dementia include frontotemporal dementia, stroke (vascular dementia) and dementia with Lewy bodies. For people who are age 65 and older with a degenerative dementia, the most common disorders are Alzheimer's disease and vascular dementia. In people who are under 65, frontotemporal dementia and Huntington's disease are also common. The damage caused by each of these diseases creates a typical pattern of cognitive loss due to the areas of the brain impacted by the underlying disease.
While there are not yet medications available to stop or reverse the damage caused by these neurodegenerative disorders, there are ways to help relieve some of the symptoms. This may improve an individual’s quality of life, ease the burden on caregivers or delay admission to a nursing home.