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Dementia

Medically reviewed by Drugs.com. Last updated on Feb 13, 2024.

Overview

Dementia is a term used to describe a group of symptoms affecting memory, thinking and social abilities. In people who have dementia, the symptoms interfere with their daily lives. Dementia isn't one specific disease. Several diseases can cause dementia.

Dementia generally involves memory loss. It's often one of the early symptoms of the condition. But having memory loss alone doesn't mean you have dementia. Memory loss can have different causes.

Alzheimer's disease is the most common cause of dementia in older adults, but there are other causes of dementia. Depending on the cause, some dementia symptoms might be reversible.

Symptoms

Dementia symptoms vary depending on the cause. Common symptoms include:

Cognitive changes

Psychological changes

When to see a doctor

See a health care professional if you or a loved one has memory problems or other dementia symptoms. It's important to determine the cause. Some medical conditions that cause dementia symptoms can be treated.

Causes

Dementia is caused by damage to or loss of nerve cells and their connections in the brain. The symptoms depend on the area of the brain that's damaged. Dementia can affect people differently.

Dementias are often grouped by what they have in common. They may be grouped by the protein or proteins deposited in the brain or by the part of the brain that's affected. Also, some diseases have symptoms like those of dementia. And some medicines can cause a reaction that includes dementia symptoms. Not getting enough of certain vitamins or minerals also can cause dementia symptoms. When this occurs, dementia symptoms may improve with treatment.

Progressive dementias

Dementias that are progressive get worse over time. Types of dementias that worsen and aren't reversible include:

Other disorders linked to dementia

Dementia-like conditions that can be reversed

Some causes of dementia-like symptoms can be reversed with treatment. They include:

Risk factors

Many factors can eventually contribute to dementia. Some factors, such as age, can't be changed. You can address other factors to reduce your risk.

Risk factors that can't be changed

Risk factors you can change

You might be able to control the following risk factors for dementia.

Complications

Dementia can affect many body systems and, therefore, the ability to function. Dementia can lead to:

Prevention

There's no sure way to prevent dementia, but there are steps you can take that might help. More research is needed, but it might be beneficial to do the following:

Diagnosis

To diagnose the cause of dementia, a health care professional must recognize the pattern of loss of skills and function. The care professional also determines what the person is still able to do. More recently, biomarkers have become available to make a more accurate diagnosis of Alzheimer's disease.

A health care professional reviews your medical history and symptoms and conducts a physical exam. Someone who is close to you may be asked about your symptoms as well.

No single test can diagnose dementia. You'll likely need a number of tests that can help pinpoint the problem.

Cognitive and neuropsychological tests

These tests evaluate your thinking ability. A number of tests measure thinking skills, such as memory, orientation, reasoning and judgment, language skills, and attention.

Neurological evaluation

Your memory, language skills, visual perception, attention, problem-solving skills, movement, senses, balance, reflexes and other areas are evaluated.

Brain scans

Laboratory tests

Simple blood tests can detect physical problems that can affect brain function, such as too little vitamin B-12 in the body or an underactive thyroid gland. Sometimes the spinal fluid is examined for infection, for inflammation or for markers of some degenerative diseases.

Psychiatric evaluation

A mental health professional can determine whether depression or another mental health condition is contributing to your symptoms.

Treatment

Most types of dementia can't be cured, but there are ways to manage your symptoms.

Medications

The following are used to temporarily improve dementia symptoms.

In 2023, the U.S. Food and Drug Administration (FDA) approved lecanemab (Leqembi) for people with mild Alzheimer's disease and mild cognitive impairment due to Alzheimer's disease.

A phase 3 clinical trial found that the medicine slowed cognitive decline in people with early Alzheimer's disease. The medicine prevents amyloid plaques in the brain from clumping. The phase 3 trial was the largest so far to study whether clearing clumps of amyloid plaques from the brain can slow the disease.

Lecanemab is given as an IV infusion every two weeks. Side effects of lecanemab include infusion-related reactions such as fever, flu-like symptoms, nausea, vomiting, dizziness, changes in heart rate and shortness of breath.

Also, people taking lecanemab may have swelling in the brain or may get small bleeds in the brain. Rarely, brain swelling can be serious enough to cause seizures and other symptoms. Also in rare instances, bleeding in the brain can cause death. The FDA recommends getting a brain MRI before starting treatment. It also recommends being monitored with brain MRIs during treatment for symptoms of brain swelling or bleeding.

People who carry a certain form of a gene known as APOE e4 appear to have a higher risk of these serious complications. The FDA recommends being tested for this gene before starting treatment with lecanemab.

If you take a blood thinner or have other risk factors for brain bleeding, talk to your health care professional before taking lecanemab. Blood-thinning medicines may increase the risk of bleeds in the brain.

More research is being done on the potential risks of taking lecanemab. Other research is looking at how effective lecanemab may be for people at risk of Alzheimer's disease, including people who have a first-degree relative, such as a parent or sibling, with the disease.

Another medicine being studied is donanemab. It targets and reduces amyloid plaques and tau proteins. It was found to slow declines in thinking and functioning in people with early Alzheimer's disease.

Therapies

Several dementia symptoms and behavior problems might be treated initially with therapies other than medicine. These may include:

Lifestyle and home remedies

Dementia symptoms and behavior problems get worse over time. Caregivers and care partners might try the following suggestions:

Alternative medicine

Several dietary supplements, herbal remedies and therapies have been studied for people with dementia. But there's no convincing evidence that these treatments are effective.

Use caution when considering taking dietary supplements, vitamins or herbal remedies, especially if you're taking other medicines. Supplements, vitamins and herbs aren't regulated. Claims about their benefits aren't always based on scientific research.

While some studies suggest that vitamin E supplements may be helpful for Alzheimer's disease, study results have been mixed. Also, high doses of vitamin E can pose risks. Taking vitamin E supplements is generally not recommended. However, including foods high in vitamin E, such as nuts, in your diet is recommended.

Other therapies

The following techniques may help reduce agitation and promote relaxation in people with dementia.

Coping and support

After being diagnosed with dementia, you'll need to consider many details to prepare you and your family members to deal with the condition.

Care and support for the person with the disease

Here are some suggestions you can try to help yourself cope with the disease:

Helping someone with dementia

You can help a person cope with the disease by listening. Offer reassurance that the person can enjoy life. Be supportive and positive, and do your best to help the person retain dignity and self-respect.

Support for caregivers and care partners

Providing care for someone with dementia is physically and emotionally demanding. You might feel angry, guilty, frustrated or worried. Grief and social isolation are common. If you're a caregiver or care partner for someone with dementia:

Preparing for an appointment

Most likely, you'll first see a health care professional if you have concerns about dementia. Or you might be referred to a doctor trained in nervous system conditions, known as a neurologist.

Here's some information to help you get ready for your appointment.

What you can do

When you make the appointment, ask if there's anything that needs to be done in advance, such as fasting before certain tests. Make a list of:

Even in the early stages of dementia, it's good to take a family member, friend or caregiver along to help you remember the information you're given.

For dementia, basic questions to ask a health care professional include:

Don't hesitate to ask other questions.

What to expect from your doctor

You're likely to be asked questions such as:

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