Understanding Alzheimer’s & Dementia
Basics of Alzheimer’s & Dementia
What is Alzheimer’s Disease?
Alzheimer’s disease is a brain disorder that slowly destroys memory and thinking skills and, eventually, the ability to carry out the simplest tasks. In most people with the disease — those with the late-onset type symptoms first appear in their mid-60s. Early-onset Alzheimer’s occurs between a person’s 30s and mid-60s and is very rare. Alzheimer’s disease is the most common cause of dementia among older adults.
The disease is named after Dr. Alois Alzheimer. In 1906, Dr. Alzheimer noticed changes in the brain tissue of a woman who had died of an unusual mental illness. Her symptoms included memory loss, language problems, and unpredictable behavior. After she died, he examined her brain and found many abnormal clumps (now called amyloid plaques) and tangled bundles of fibers (now called neurofibrillary, or tau, tangles).
These plaques and tangles in the brain are still considered some of the main features of Alzheimer’s disease. Another feature is the loss of connections between nerve cells (neurons) in the brain. Neurons transmit messages between different parts of the brain, and from the brain to muscles and organs in the body. Many other complex brain changes are thought to play a role in Alzheimer’s, too.
This damage initially takes place in parts of the brain involved in memory, including the entorhinal cortex and hippocampus. It later affects areas in the cerebral cortex, such as those responsible for language, reasoning, and social behavior. Eventually, many other areas of the brain are damaged.
How many Americans have Alzheimer’s disease?
Estimates vary, but experts suggest that more than 6 million Americans age 65 and older may have Alzheimer’s. Many more under age 65 also have the disease. Unless Alzheimer’s can be effectively treated or prevented, the number of people with it will increase significantly if current population trends continue. This is because increasing age is the most important known risk factor for Alzheimer’s disease.
What does Alzheimer’s disease look like?
Memory problems are typically one of the first signs of Alzheimer’s, though initial symptoms may vary from person to person. A decline in other aspects of thinking, such as finding the right words, vision/spatial issues, and impaired reasoning or judgment, may also signal the very early stages of Alzheimer’s disease. Mild cognitive impairment (MCI) is a condition that can be an early sign of Alzheimer’s, but not everyone with MCI will develop the disease.
People with Alzheimer’s have trouble doing everyday things like driving a car, cooking a meal, or paying bills. They may ask the same questions over and over, get lost easily, lose things or put them in odd places, and find even simple things confusing. As the disease progresses, some people become worried, angry, or violent.
How long can a person live with Alzheimer’s disease?
The time from diagnosis to death varies — as little as three or four years if the person is older than 80 when diagnosed, to as long as 10 or more years if the person is younger.
Alzheimer’s disease is currently ranked as the sixth leading cause of death in the United States, but recent estimates indicate that the disorder may rank third, just behind heart disease and cancer, as a cause of death for older people.
Currently, there is no cure for Alzheimer’s disease, though there has been significant progress in recent years in developing and testing new treatments. Several medicines have been approved by the U.S. Food and Drug Administration to treat people with Alzheimer’s.
Learn more about how Alzheimer’s disease is treated.
Types of dementia
- Alzheimer’s Disease
- Frontotemporal Dementia
- Lewy Body Dementia
- Vascular Dementia
What is happening in the brain?
Alzheimer’s disease: Abnormal deposits of proteins form amyloid plaques and tau tangles throughout the brain.
Frontotemporal dementia: Abnormal amounts or forms of tau and TDP-43 proteins accumulate inside neurons in the frontal and temporal lobes.
Lewy body dementia: Abnormal deposits of the alpha-synuclein protein, called “Lewy bodies,” affect the brain’s chemical messengers.
Vascular dementia: Conditions, such as blood clots, disrupt blood flow in the brain.
Note that these changes are just one piece of a complex puzzle that scientists are studying to understand the underlying causes of these forms of dementia and others.
Symptoms of Alzheimer’s disease
- Wandering and getting lost
- Repeating questions
- Problems recognizing friends and family
- Impulsive behavior
- Cannot communicate
Symptoms of Frontotemporal Dementia
Behavioral and Emotional
- Difficulty planning and organizing
- Impulsive behaviors
- Emotional flatness or excessive emotions
- Shaky hands
- Problems with balance and walking
- Difficulty making or understanding speech
There are several types of frontotemporal disorders, and symptoms can vary by type.
Symptoms of Lewy body dementia
- Inability to concentrate, pay attention, or stay alert
- Disorganized or illogical ideas
- Muscle rigidity
- Loss of coordination
- Reduced facial expression
- Excessive daytime sleepiness
Symptoms of vascular dementia
- Forgetting current or past events
- Misplacing items
- Trouble following instructions or learning new information
- Hallucination or delusions
- Poor judgment
Typical age of diagnosis for Alzheimer’s disease: Mid-60s and above, with some cases in the mid-30s to 60s
Typical age of diagnosis of frontotemporal dementia: Between 45 and 64
Typical age of diagnosis of Lewy body dementia: 50 or older
Typical age of diagnosis of vascular dementia: Over 65
You may share the same memories from your youth with us time and time again, but the sheer joy you show in telling those stories with such a big smile goes beyond making up the loss of new stories.