Alzheimer’s used to be an obscure disease, but is now the sixth leading cause of death in the United States. The reason for this increase is as puzzling as the disease itself.
- Alzheimer’s is a disease that destroys brain cells. This destruction causes problems with memory, thinking, behavior, and eventually the very functioning of the body.
- Alzheimer’s is a progressive disease that starts with mild mental and physical changes and leads to severe problems that end in death.
- It is the most common form of dementia (loss of memory and intellectual abilities).
- But despite its prevalence, scientists are still puzzled by what exactly causes the disease.
The brains of people with Alzheimer’s disease look atrophied and have damage that is visible on autopsy - called plaques and tangles. The plaques build up between nerve cells and contain a protein called beta-amyloid. The tangles are twisted fibers of another protein called tau protein.
Some plaques and tangles are found in normal brains, but Alzheimer’s disease patients develop many more than a normal person. What causes the plaques and tangles is unknown - as is just how these brain changes destroy the nerves. The disease appears to attack the outer layer of the brain known as the cortex, especially in areas of the brain responsible for memory and learning. The cells of the brain lose function and eventually die.
It is a mistake to think Alzheimer’s disease only occurs in older people. While the vast majority of people who get the disease are over 65, people in their 30s, 40s and 50s also can also get the disease. Currently, there are no cures, only treatments that stall the progression of the disease. The average life expectancy after diagnosis is 7 years.