Senile dementia - Alzheimer's type (SDAT); SDAT
Dementia is a loss of brain function that occurs with certain diseases. Alzheimer's disease (AD), is one form of dementia that gradually gets worse over time. It affects memory, thinking, and behavior.
Memory impairment, as well as problems with language, decision-making ability, judgment, and personality, are necessary features for the diagnosis.
Age and family history are risk factors for AD.
Other risk factors that are not as well proven include:
There are two types of AD -- early onset and late onset.
The cause of AD is not entirely known, but is thought to include both genetic and environmental factors. A diagnosis of AD is made when certain symptoms are present, and by making sure other causes of dementia are not present.
The only way to know for certain that someone has AD is to examine a sample of their brain tissue after death. The following changes are more common in the brain tissue of people with AD:
When nerve cells (neurons) are destroyed, there is a decrease in the chemicals that help nerve cells send messages to one another (called neurotransmitters). As a result, areas of the brain that normally work together become disconnected.
The buildup of aluminum, lead, mercury, and other substances in the brain is no longer believed to be a cause of AD.
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