What happens to the brain in Alzheimer's disease?
Although we still don’t know how the Alzheimer’s disease process begins, it seems likely that damage to the brain starts a decade or more before problems become evident. During the preclinical stage of Alzheimer’s disease, people are free of symptoms, but toxic changes are taking place in the brain. Abnormal deposits of proteins form amyloid plaques and tau tangles throughout the brain, and once-healthy neurons begin to work less efficiently. Over time, neurons lose the ability to function and communicate with each other, and eventually they die. Before long, the damage spreads to a nearby structure in the brain called the hippocampus, which is essential in forming memories. As more neurons die, affected brain regions begin to shrink. By the final stage of Alzheimer’s, damage is widespread, and brain tissue has shrunk significantly. How many Americans have Alzheimer’s disease? Estimates vary, but experts suggest that as many as 5.1 million Americans have Alzheimer’s disease. Unless the disease can be effectively treated or prevented, the number of people with it will increase significantly if current population trends continue. That’s because the risk of Alzheimer’s increases with age, and the U.S. population is aging. The number of people with Alzheimer’s doubles for every 5-year interval beyond age 65. How long can a person live with Alzheimer’s disease?
Alzheimer’s is a slow disease that progresses in three stages—an early, preclinical stage with no symptoms, a middle stage of mild cognitive impairment, and a final stage of Alzheimer’s dementia. The time from diagnosis to death varies—as little as 3 or 4 years if the person is older than 80 when diagnosed to as long as 10 or more years if the person is Not everyone will experience the same symptoms or progress at the same rate the 7 stages that I will be going over was developed by Dr.Barry Reisberg clinical director of the New York University of Medicine Silberstein Aging and Dementia Research Center.
Stage 1:| No impairment (normal function)
The person does not experience any memory problems. An interview with a medical professional does not show any evidence of symptoms of dementia.|
Stage 2: | Very mild cognitive decline (may be normal age-related changes or earliest signs of Alzheimer's disease) The person may feel as if he or she is having memory lapses — forgetting familiar words or the location of everyday objects. But no symptoms of dementia can be detected |
| Stage 3: Mild cognitive decline (early-stage Alzheimer's can be diagnosed in some, but not all, individuals with these symptoms) Friends, family or co-workers begin to notice difficulties. During a detailed medical interview, doctors may be able to detect problems in memory or concentration. Common stage 3...