Alzheimer’s Disease

What is Alzheimer’s disease?

Alzheimer’s disease is the most common cause of dementia. It is caused by a buildup of proteins in the brain that damage and eventually kill neurons (brain cells). This causes significant declines in cognitive abilities like memory, comprehension, attention, and behavior.

Alzheimer’s is a progressive disease that gets worse over time. There is no cure for it, but treatments can help control symptoms, slow the progression of the disease, and make living with Alzheimer’s more manageable.

Most common symptoms

Alzheimer’s disease causes memory loss and other cognitive problems.

• Memory loss is often the earliest symptom. Short-term memory is affected first. People may forget everyday things like the day of the week, where they parked the car, or a monthly payment. As the disease progresses, long-term memory is affected. This can be very upsetting. People with late-stage disease often do not remember who they are or who their family members are.
• Cognitive dysfunction: People with Alzheimer’s lose executive functions, which are the mental skills and processes needed to plan, solve problems, focus, and control their emotions and impulses. Eventually, they have difficulty performing everyday activities like getting dressed, bathing, and going to the bathroom. And they need others to take care of them.

The stages of Alzheimer’s

Alzheimer’s disease worsens gradually over the years, from people having no symptoms at all to having very severe symptoms. Understanding the stages can help reduce its impact and help people plan and prepare for the future.

• Preclinical (before symptoms appear)
  People in this stage do not have any noticeable symptoms of Alzheimer’s. If they were tested though, there would be early signs of it. An imaging test, like an MRI or biomarkers on a blood test, can detect the development of the disease. This testing is still being studied and is not yet routinely used by doctors.
• Mild cognitive impairment
  Individuals will begin to experience minor memory loss and cognitive decline. It may cause small problems, but generally, people can continue to function independently, work, and socialize. In this stage, it is important to review current lifestyle and medications to see if any habits or medications may be contributing to cognitive problems. In addition, it’s important to start setting goals and plans for care in the later stages.
• Early dementia
  Short-term memory loss and cognitive problems start to interfere with work, independence, and interactions with other people. Individuals may have trouble concentrating or communicating. They may need someone to organize their schedule, prepare meals, and supervise the use of appliances in their home. Driving ability is likely to be affected. In addition, they may experience trouble sleeping, depression, personality changes, or irritability. It is possible that the individual will not be able to communicate their own medical decisions or goals for medical care.
• Moderate dementia
  Cognitive problems begin to affect the ability to do basic things like bathe, get dressed, or use the bathroom. Individuals may need someone to prompt them to do basic self care, or even provide hands-on help. It is highly likely that individuals will not be able to communicate their own medical decisions.
• Severe dementia
  At this point, the individual with dementia has problems with basic functions of communication, walking, swallowing, and maintaining control of the bladder and bowels. They are completely dependent on others for their care. If a person in this stage is losing weight or having repeated infections, this may be a sign that the end of life is near.

Causes of Alzheimer’s disease

Alzheimer’s disease is caused by two types of proteins—amyloid and tau—accumulating in the brain. Scientists do not know how to prevent this from happening.

When amyloid builds up in the brain, it forms plaque that damages and eventually kills neurons. When tau accumulates, it forms tangles within brain cells that prevent neurons from making important connections.

Over time, these plaques and tangles cause areas of the brain to shrink, leading to a decline in the functions that those areas govern. The areas of the brain that often shrink first are those responsible for memories.

Risk factors for Alzheimer’s include having a family history of Alzheimer's. Having a first-degree relative (parent or sibling) with Alzheimer's increases the risk by 10% to 30%. People with two or more siblings with Alzheimer’s are three times more likely to get it than the general population.

How is Alzheimer’s disease diagnosed?

There is not one single test or biomarker that diagnoses Alzheimer's. Your doctor will do a comprehensive exam and will look for signs that the symptoms might be caused by a different, reversible problem that can mimic dementia.

The evaluation includes cognitive tests, a physical examination, and blood tests. The cognitive tests objectively assess how your memory and skills of executive function are working. They may refer you to a neurologist or neuropsychiatrist for additional testing.

The specialist might want to view the structure of the brain with a CT scan or MRI—imaging tests that show detailed pictures of the brain to rule out other problems that can cause cognitive changes. Imaging may show atrophy (shrinking) of different parts of the brain. Other more detailed testing may be necessary.

Next steps

The symptoms of Alzheimer’s progress over years.

An individual with Alzheimer’s and their family may start to notice subtle changes in memory or behavior. For example, a person with Alzheimer's may forget very simple things, or mix up words or have difficulty remembering what objects are called.

Contact your healthcare provider if you start to notice any symptoms of Alzheimer's. It is important to have a careful evaluation for all possible causes of cognitive change.

Treatment

There are treatments available that can help control symptoms, slow the progression of the disease, prevent complications, and make living with the disease easier.

Medication

As the brain cells in Alzheimer’s disease are damaged and start to die, there is a decrease in important chemical messengers (called neurotransmitters) that these brain cells send. Several medications can enhance these neurotransmitters. Acetylcholinesterase inhibitors (donepezil, galantamine, rivastigmine) and the NMDA receptor antagonist called memantine may help slow the progression of the disease.

Therapies

Physical, occupational, speech, and nutritional therapies are very important parts of treatment. They help a person maintain independence as long as possible. They can also help a person and their family adapt to changing needs over time. Group activities, such as dementia day programs, can be very helpful.

Preventative tips

Cardiovascular disease has been linked to an increased risk of Alzheimer's disease. You may be able to slow down developing Alzheimer’s by improving your cardiovascular health. Some changes to make include:

• Stop smoking
• Keep alcohol to a minimum
• Eat a healthy, balanced diet
• Exercise regularly
• Make sure your blood pressure is checked and managed
• If you have diabetes, follow the diet plan and take your medication

It may also be possible to reduce your risk of Alzheimer's and other types of dementia by staying social and keeping your mind active. Here are some ways to keep the brain stimulated:

• Reading
• Learning foreign languages
• Playing musical instruments
• Volunteering in your local community
• Taking part in group sports, such as bowling
• Trying new activities or hobbies
• Maintaining an active social life