HIV and the Brain

HIV can cause real problems for the human central nervous system because it has the ability to cross the blood-brain barrier and gain direct contact with your brain and spinal cord tissues.

Researchers are still working to discover just what HIV does to injure your central nervous system, but we know that the virus itself can damage your ability to think (your “cognitive” ability) and to function in everyday life.

When that happens, healthcare providers refer to the condition as “HIV-associated dementia” or AIDS dementia complex (ADC). If you are HIV-positive, ADC is considered an AIDS-defining condition.

In the early days of the HIV/AIDS epidemic in the U.S., between 40–60% of people living with HIV/AIDS experienced some type of ADC. But since antiretroviral therapy became available, the incidence of ADC has dropped significantly.

Most of the time, HIV-related cognitive issues are associated with advanced HIV disease and low CD4 counts (less than 200 cells/mm3). Taking HIV medications may prevent or delay the onset of ADC—and they may also improve your mental function if you already have symptoms of ADC.

Diagnosing HIV-Related Cognitive Issues

Diagnosis can be a challenge because there are other things besides your HIV disease that can affect your ability to think and function—including opportunistic infections, depression or other mental health issues, medication-related side effects, and aging.

There are also different levels of severity for HIV-related dementia:

Minor Cognitive Motor Disorder (MCMD) (PDF)
This form of HIV-related dementia is milder than full-blown ADC. Some of the symptoms include:

  • Difficulty concentrating
  • Forgetfulness
  • Slowed movements
  • Changes in personality
  • Lack of coordination

AIDS Dementia Complex
ADC is typically seen in the late stages of HIV/AIDS. The symptoms vary widely from person to person and can include:

  • Poor concentration
  • Mental slowness
  • Difficulty learning new things
  • Changes in behavior
  • Forgetfulness/Memory loss
  • Confusion
  • Difficulty finding words
  • Withdrawal from hobbies or social activities
  • Depression

Symptoms of worsening dementia can include:

  • Speech problems
  • Balance problems
  • Muscle weakness
  • Vision problems
  • Loss of bladder/bowel control

It’s important to remember that these symptoms can be caused by a wide range of conditions, including opportunistic infections and HIV-related cancers that particularly affect the brain and central nervous system. These must always be ruled out first.

It takes a team of skilled professionals—including those with training in neurology—to make a diagnosis of ADC. As part of evaluating your condition, your care team will look at all aspects of your health, including:

  • The scope of your HIV disease
  • The state of your physical health
  • The state of your mental health (including any pre-existing conditions like depression)
  • How well you are able to function in your daily life

Treatment Options

If it isn’t treated, ADC can be fatal. Currently, the most effective treatment for ADC appears to be antiretroviral therapy, especially zidovudine (AZT). Medications that are used to treat other mental conditions, like depression, can alleviate some of the behavioral symptoms. Check with your healthcare provider for more details.

For more information, see the National Institute of Neurological Disorders and Stroke’s Neurological Complications of AIDS Information Page.

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Last revised: 06/08/2010