Dementia is a general term for loss of memory, language, problem-solving and other thinking abilities that are severe enough to interfere with daily life. It is a description of the state of a person’s mental function, which is related to a group of diseases, including Alzheimer’s Disease. It’s estimated that about 50% of people ages 85 and older have dementia, according to the Cleveland Clinic.
Deeper dive
Dementia is characterized by a decline in mental function from a previously higher level that’s severe enough to interfere with daily living. A person with dementia has two or more of these specific difficulties, including a decline in:
- Memory.
- Reasoning.
- Language.
- Coordination.
- Mood.
- Behavior.
Dementia develops when the parts of the brain involved with learning, memory, decision-making or language are affected by disease or deterioration.
The most common cause of dementia is Alzheimer’s disease which accounts for 60-80% of cases, according to the Alzheimer’s Association. However, other types of dementia include:
- Vascular dementia.
- Dementia with Lewy bodies.
- Frontotemporal dementia.
- Mixed dementia (e.g., Alzheimer’s and vascular dementias).
- Parkinson’s disease related dementia.
- Dementia-like conditions due to reversible causes, such as medication side effects, excessive alcohol or drug use, or thyroid problems.
Dementia is caused by damage to brain cells. This damage interferes with the ability of brain cells to communicate with each other. Different types of dementia are associated with particular types of brain cell damage in particular regions of the brain. While most changes in the brain that cause dementia are permanent and worsen over time, thinking and memory problems caused by some conditions may improve when treated or addressed.
While the odds of developing dementia increase with age, especially among those 85 or older, it is not a normal part of aging. Many people live well into their 90s and beyond without any signs of dementia.