Alzheimer’s disease symptoms, diagnosis & treatment

What causes Alzheimer's disease?

While the exact cause of most AD is unknown, it is believed to be caused by a combination of genetic, environmental and lifestyle factors. Key features of AD are complex changes in the brain that may be closely related to the formation of abnormal clumps of tissue (beta-amyloid plaques) and tangled bundles of fibers (tau tangles). These toxic brain changes can begin 10 years or more before AD symptoms develop. Most experts believe that the development of amyloid and tau play an important role in blocking communication among the brain’s nerve cells and disrupting processes that cells need to survive. The nerve cells (neurons) stop functioning, or lose their connections to other neurons, and die. Neurons carry messages between parts of the brain, and from the brain to muscles and organs.

Other, less well understood changes also occur in an AD patient’s brain. A genetic mutation is believed to cause, or be closely related to, early onset AD. If a family member has AD, your chances of developing it are increased. Early onset AD is rare, comprising only 10% of all AD cases.

A specific gene that causes late-onset AD has not been identified. However, having a form of the apolipoprotein E (APOE) gene increases a person’s risk of developing AD and at a younger age. More research is needed on the APOE gene. Having this gene does not mean the person will develop AD, and some people without APOE develop AD. Other genetic mutations are associated with AD. Most people with Down syndrome develop AD, and this may be because they have an extra copy of chromosome 21. This chromosome contains the gene that generates AD’s signature amyloid plaques.

Damage caused by AD occurs in parts of the brain (hippocampus and entorhinal cortex) that are essential to the formation of memories and learning. As the disease progresses and more neurons die, other parts of the brain are affected and start to shrink. These brain changes are irreversible. By the final stage of AD, the brain has significantly decreased in size.

Brain changes related to aging can harm brain cells and neurons. These changes include: parts of the brain shrink (atrophy), inflammation, damage to blood vessels, production of free radicals (unstable molecules inside the body), and a loss of cells’ ability to produce energy.

AD research is also focused on the connection between brain deterioration and conditions such as heart disease, stroke, high blood pressure, diabetes and obesity. One theory being studied in clinical trials is that decreasing these very common diseases associated with aging may also decrease the risk of AD. That’s why advice about preventing AD includes encouragement to eat a balanced and nutritious diet, get regular physical activity, and maintain social connections and regular interactions with others.

What are the symptoms of Alzheimer's disease?

Symptoms are progressive and may include:

Difficulty remembering newly learned information or following a conversation. This is more than occasionally forgetting names or a train of thought. Serious memory loss, confusion or other changes in the way the brain works can indicate failing brain cells.
Wandering and getting lost
Difficulty sleeping
Agitation, anxiety, or aggression
Trouble handling money and paying bills
Repeating questions, or something they just said
Disorientation and confusion about events, time and place
Decreased or poor judgment
Misplacing things; inability to retrace steps to find the missing item
Challenges planning things, solving problems, or completing familiar tasks, especially multi step tasks like dressing
Mood, behavior, and personality changes
Difficulty recognizing family and friends
Inability to cope in new situations
Impulsive behavior
Withdrawal from work and social activities
Trouble understanding visual images and spatial relationships
Difficulty speaking or writing
Not understanding that they have memory and confusion problems
Being suspicious or paranoid about the actions or motives of family, friends, co-workers and caregivers
Have hallucinations and delusions
Problems swallowing and walking in the advanced stages of AD

People react differently to AD’s early brain changes or damage. Some memory problems may be a condition called mild cognitive impairment (MCI). It can be diagnosed as having more memory problems than other people the same age. They may lose things more often, forget events or appointments, struggle to find the correct word for something, forget names, have movement difficulties, and problems with the sense of smell. People with MCI can still take care of themselves and accomplish their normal daily activities. They have a greater risk of developing AD, but not all of them do so.

As the disease progresses, patients with moderate AD have worsening problems with language, reasoning, correctly identifying sounds and smells, confusion, and recognizing family and friends. They’re unable to learn new things or accomplish multi step tasks. They may begin to act impulsively, and have hallucinations, delusions and paranoia.

With severe AD, patients can no longer follow a conversation, interact with their environment or other people, and have to rely on others for all their care and normal daily routine. Near the end of life, they may stay in bed most or all of the time as the body shuts down.

How is Alzheimer's disease diagnosed?

To determine if a person with memory problems has AD, doctors use several methods, including:

Asking about the person’s health history, ability to carry out daily activities, and any changes in behavior or personality.
Conducting tests to evaluate memory, problem solving, attention, counting and language.
Ruling out other possible causes by conducting standard medical tests (blood, urine, others). Other treatable diseases can cause many of the same symptoms associated with AD.
Brain scans (CT, MRI, or PET) are done to support an AD diagnosis or rule out other causes for symptoms.
Repeating any/all of the above tests to track how cognitive functions are changing over time.

Advances in brain imaging are letting researchers see the development and spread of abnormal amyloid and tau proteins in the living brain, as well as changes in brain structure and function. Scientists are also studying the early changes in the brain and body fluids that can occur years before AD symptoms appear.

It’s important to talk with your doctor if you’re having any of the symptoms listed above. Getting an early diagnosis permits early treatments to begin, as well as helping the family plan for the future. Because AD is progressive and irreversible, it’s important to take care of financial and legal matters, establish a living will, address future living arrangements and caregiving, and develop support networks.

Are there any treatments for Alzheimer's disease?

AD treatments focus on maintaining brain function, treating the underlying biological disease process and managing behavioral symptoms. There is no cure for AD; no treatment can restore lost memories or cognitive function.

The U.S. Food and Drug Administration (FDA) has approved the drug aducanumab for use with AD patients. The FDA gave it accelerated approval because, as the first drug to address the biology of AD, it may slow the progression of AD symptoms. It works by removing amyloid deposits from the brain, with the reasonable likelihood that it will reduce cognitive and functional decline. It was tested on AD patients in the early stages of the disease and in patients with MCI. To increase its effectiveness, aducanumab should be given as soon as symptoms begin to have an impact on daily life. The FDA’s accelerated approval process requires additional testing to confirm the anticipated benefits. The FDA can withdraw the drug if it fails to produce the expected results. Test results are not expected until 2030.

Other medications can temporarily show the worsening of symptoms and behavior problems, and improve quality of life for AD patients. They work by regulating neurotransmitters, the chemicals that transmit messages between the brain’s nerve cells. However, they cannot change the underlying disease process and are not effective for all patients. If they are effective, it’s only for a limited time. Donepezil, rivastigmine, and galantamine are used to treat mild to moderate AD symptoms. Moderate to severe AD is treated with donepezil, memantine, the rivastigmine patch, and a combination of memantine and donepezil. Because AD is such a complex disease, researchers think it’s unlikely that one medication will successfully treat all AD patients.

Treating the behavioral symptoms of AD (agitation, anxiety, aggression, sleeplessness) can make the patient more comfortable and make caregiving easier. Providing care and assistance to family members and other caregivers of AD patients is an indirect but very important part of treatment. AD care demands a significant amount of physical, emotional and financial commitment. Teaching caregivers coping skills, helping them develop a support network, and providing respite care (a break from caregiving to help them continue to be caregivers) can greatly improve quality of life.

Alzheimer’s Association. (N.d.). What is Alzheimer’s Disease? Retrieved 10-20-21, {https://www.alz.org/alzheimers-dementia/what-is-alzheimers}

National Institute on Aging. (N.d.). Alzheimer’s Disease Fact Sheet. Retrieved 10-20-21, {https://www.nia.nih.gov/health/alzheimers-disease-fact-sheet}

Mayo Clinic. (June 2021). Alzheimer’s Disease. Retrieved 10-20-21, {https://www.mayoclinic.org/diseases-conditions/alzheimers-disease/symptoms-causes/syc-20350447}

Mayo Clinic. (June 2021). Alzheimer’s Disease: Diagnosis and Treatment. Retrieved 10-20-21,

{https://www.mayoclinic.org/diseases-conditions/alzheimers-disease/diagnosis-treatment/drc-20350453}

Medically reviewed by:

Dr. Desiree Levyim

Dr. Desiree Levyim is a board eligible neurologist in practice since 2020. She joins TeleMed2U in our mission to provide increased access to healthcare.

‍Meet our doctors

‍

Alzheimer’s Disease