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HIV-Associated Dementia


Juebin Huang

, MD, PhD, Department of Neurology, University of Mississippi Medical Center

Last full review/revision Mar 2021| Content last modified Mar 2021

HIV-associated dementia is progressive deterioration in mental function due to infection of the brain with human immunodeficiency virus (HIV).

  • Unlike almost all other forms of dementia, HIV-associated dementia tends to occur in younger people.
  • Usually, the dementia begins subtly but progresses steadily over a few months or years, typically after other symptoms of HIV infection develop.
  • Doctors diagnose HIV-associated dementia based on symptoms, mental status testing, blood tests for HIV, and imaging tests.
  • Treating HIV infection with antiretroviral therapy sometimes dramatically improves mental function but does not cure the dementia.

(See also Overview of Delirium and Dementia and Dementia.)

In the late stages of HIV infection, the virus may directly infect the brain. HIV damages nerve cells, causing dementia. Dementia is a slow, progressive decline in mental function including memory, thinking, judgment, and the ability to learn.

In people with HIV infection, dementia may also result from other disorders, including lymphomas that affect the brain and infections that people with HIV infection are prone to get because their immune system is weakened. These infections are called opportunistic infections and include progressive multifocal leukoencephalopathy, toxoplasmosis (a parasite infection), and meningitis due to fungi (see table Common Opportunistic Infections Associated With AIDS). Some of these disorders can be treated, resulting in some improvement.

Unlike almost all other forms of dementia, HIV-associated dementia tends to occur in younger people.

Dementia occurs in 7 to 27% people with late-stage HIV infection, but 30 to 40% may have milder forms of HIV-associated dementia.

Dementia differs from delirium, which is characterized by an inability to pay attention, disorientation, an inability to think clearly, and fluctuations in the level of alertness.

  • Dementia affects mainly memory, and delirium affects mainly attention.
  • Dementia typically begins gradually and has no definite beginning point. Delirium begins suddenly and often has a definite beginning point.

Symptoms of HIV-Associated Dementia

HIV-associated dementia usually begins subtly but progresses steadily over a few months or years. It usually develops after other symptoms of HIV infection.

Early symptoms of HIV-associated dementia include

  • Slowed thinking and expression
  • Difficulty concentrating
  • Apathy

But insight is not affected. Movements are slow, muscles are weak, and coordination may be impaired.

In some people, a psychosis, such as hallucinations, delusions, or paranoia, develops. Some people become manic. That is, they become very restless and overactive. They may speak rapidly and act without good judgment.

Without treatment, HIV-associated dementia usually progresses, eventually becoming severe.

Diagnosis of HIV-Associated Dementia

  • A doctor's evaluation for dementia, HIV infection, or both
  • Blood tests to determine how severe HIV infection is
  • Magnetic imaging and usually a spinal tap

Generally, the diagnosis of dementia in people with HIV infection is similar to that of other dementias.

Doctors must determine whether a person has dementia and, if so, whether the dementia is HIV-associated dementia.

Diagnosis of dementia

Doctors base a diagnosis of dementia on the following:

  • Symptoms, which are identified by asking the person and family members or other caregivers questions
  • Results of a physical examination, including a neurologic examination
  • Results of a mental status test
  • Results of additional tests, such as computed tomography (CT) or magnetic resonance imaging (MRI)

Mental status testing, consisting of simple questions and tasks, helps doctors determine whether people have dementia.

Neuropsychologic testing, which is more detailed, is sometimes needed. This testing covers all the main areas of mental function, including mood, and usually takes 1 to 3 hours. This testing helps doctors distinguish dementia from other conditions that can cause similar symptoms, such as age-associated memory impairment, mild cognitive impairment, and depression.

Information from the above sources can usually help doctors rule out delirium as the cause of symptoms (see table Comparing Delirium and Dementia). Doing so is essential because delirium, unlike dementia, can often be reversed if promptly treated.

Diagnosis of HIV-associated dementia

If people who are not known to have HIV infection develop symptoms of dementia and have risk factors for HIV infection, doctors may suspect HIV-associated dementia and do tests to check for HIV as well as for dementia.

When HIV infection is diagnosed or when mental function changes in people with HIV infection, magnetic resonance imaging (MRI) is done to check for other causes of brain dysfunction, such as toxoplasmosis or lymphoma. When mental function changes suddenly, the cause must be identified quickly because early treatment can prolong life. Untreated, HIV-associated dementia may cause death within 6 months.

Unless results of CT or MRI suggest that pressure within the skull is increased, doctors usually do a spinal tap (lumbar puncture) to obtain a sample of cerebrospinal fluid, which is analyzed. Findings can support but not confirm the diagnosis of HIV-associated dementia.

If people have HIV infection or if HIV-associated dementia is suspected, doctors also do blood tests to measure the following:

  • The number of white blood cells called CD4 lymphocytes (the CD4 count)
  • The amount of HIV (viral load)

These tests help determine how severe the HIV infection is. Having with a very low CD4 count and a very high viral load increases the risk of developing brain infections, lymphoma, and HIV-associated dementia.

Treatment of HIV-Associated Dementia

  • Antiretroviral drugs

Without treatment, HIV-associated dementia can be fatal. However, when HIV infection is treated with antiretroviral therapy (ART), mental function sometimes dramatically improves. ART consists of combinations of the drugs used to treat HIV infection. However, because the infection is not cured, dementia may recur.

Treatment also includes general measures to provide support, as for other dementias.

Safety and supportive measures

Creating a safe and supportive environment can be very helpful.

Generally, the environment should be bright, cheerful, safe, stable, and designed to help with orientation. Some stimulation, such as a radio or television, is helpful, but excessive stimulation should be avoided.

Structure and routine help people with HIV-associated dementia stay oriented and give them a sense of security and stability. Any change in surroundings, routines, or caregivers should be explained to people clearly and simply.

Following a daily routine for tasks such as bathing, eating, and sleeping helps people with HIV-associated dementia remember. Following a regular routine at bedtime may help them sleep better.

Activities scheduled on a regular basis can help people feel independent and needed by focusing their attention on pleasurable or useful tasks. Such activities should include physical and mental activities. Activities should be broken down in small parts or simplified as the dementia worsens.

Care for caregivers

Caring for people with dementia is stressful and demanding, and caregivers may become depressed and exhausted, often neglecting their own mental and physical health. The following measures can help caregivers (see table Caring for Caregivers):

  • Learning about how to effectively meet the needs of people with dementia and what to expect from them: Caregivers can get this information from nurses, social workers, organizations, and published and online materials.
  • Seeking help when it is needed: Caregivers can talk to social workers (including those in the local community hospital) about appropriate sources of help, such as day-care programs, visits by home nurses, part-time or full-time housekeeping assistance, and live-in assistance. Counseling and support groups can also help.
  • Caring for self: Caregivers need to remember to take care of themselves. They should not given up their friends, hobbies, and activities.

End-of-life issues

Before people with HIV-associated dementia become too incapacitated, decisions should be made about medical care, and financial and legal arrangements should be made. These arrangements are called advance directives. People should appoint a person who is legally authorized to make treatment decisions on their behalf (a health care proxy). They should discuss their health care wishes with this person and their doctor. Such issues are best discussed with all concerned long before decisions are necessary.

As HIV-associated dementia worsens, treatment tends to be directed at maintaining the person’s comfort rather than at attempting to prolong life.

More Information

The following are some English-language resources that may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

  • This web site provides information about the causes, symptoms, treatments, and stages of dementia.
  • Health Direct: Dementia Video Series: These videos provide general information about dementia, recommendations about the warning signs of dementia, treatment and research, and caring for a person with dementia. It also provides links to articles on similar topics.
  • National Institute of Neurological Disorders and Stroke's Dementia Information Page: This web site provides information about treatments and prognosis, and links to clinical trials.

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