HIV-associated dementia

Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at October 22, 2016
StartDiseasesHIV-associated dementia

Decline in cognitive ability is a complication of HIV/AIDS. Although the exact symptoms differ from person to person, HIV dementia (also known as HIV-associated dementia) is a condition defined by cognitive impairment and difficulty functioning in day to day life.

Contents

Definition & Facts

HIV can result in a number of neurological and cognitive problems, collectively known as HIV-associated neurocognitive disorders. HIV dementia typically affects patients with a severe and advanced infection and results from the infection's effect on grey matter in the brain.

HIV dementia results in memory loss, difficulty concentrating, apathy, behavioral changes and mood changes, difficulties with movement, impairment in motor skills. The increased use of antiretroviral therapy has reduced the incidence of HIV dementia greatly.

Symptoms & Complaints

At first, the symptoms of AIDS dementia are subtle and may be underestimated. However, though they vary widely from person to person, with time, these symptoms gradually become severe and can cause sudden death. Symptoms of early HIV dementia include the following:

With time, the disease worsens. Symptoms of worsening HIV dementia include the following:

In rare occasions, an HIV dementia patient can experience more symptoms that include the following:

Without highly active antiretroviral therapy (HAART), these symptoms steadily continue to worsen and eventually lead to a vegetative state. A person who is in this state has minimal awareness of their surrounding and is incapable of interacting.

Causes

Research is still underway to discover exactly how the human immunodeficiency virus (HIV) damages brain cells. Viral proteins may damage nerve cells by triggering an inflammatory response in the central nervous system. Consequently, there is a reduction in neurons and grey matter.

Those who are older than 50 and are infected with HIV are at a higher risk for HIV dementia than those 40 and younger. It is theorized that HIV may speed up the aging process of the brain. HIV patients who also have hepatitis C are at an increased risk of HIV dementia.

Diagnosis & Tests

Diagnosis begins with a physical examination, medical history, and family history. A patient's physician or team of physicians must rule out other possible causes of dementia like metabolic disorders, stroke, tumor, and infections by carrying out thorough evaluations to determine the cause of these symptoms in patients. Assuming that the patient has already been tested as positive for HIV, tests that may be conducted to determine if a patient has HIV dementia include the following:

  • Imaging studies. Magnetic resonance imaging (MRI) and computed tomography (CT) scan can help detect some changes in the brain that support the diagnosis of the disease. Since brain changes in HIV dementia often worsen over time, physicians usually repeat these studies periodically. MRI and CT scans give a detailed 3-dimensional picture of the brain and can show cerebral atrophy (brain shrinkage) that is consistent with HIV dementia and changes in the appearance of different parts of the brain.
  • Electroencephalography. For electroencephalography, doctors attach a series of electrodes to the scalp and read and record the electrical activity of the brain. The electronic activity of the brain is slower than normal in the lower stages of HIV dementia.
  • Neuropsychological testing. This testing is the most efficient method of pinpointing and documenting cognitive abilities. Neuropsychological tests involve the patient answering questions and performing tasks that are linked to specific structures of the brain and thus test their function.
  • Neurological examinations may also be performed to assess motor and sensory responses.

Treatment & Therapy

HIV dementia can be treated and prevented efficaciously with antiretroviral therapy (ART). Antiretroviral therapy can include drugs like zidovudine (AZT). AZT is an effective drug because it crosses the blood-brain barrier.

Other drugs such as stavudine (d4T), nevirapine, efavirenz (this drug is not recommended for patients with psychiatric illnesses because it increases suicide risk), abacavir, and indinavir can also fight HIV infection and HIV dementia. Patients can also take medications such as antipsychotics, anticonvulsants, and antidepressants to relieve some of the symptoms. 

Prevention & Prophylaxis

Prevention of HIV dementia involves prevention of HIV (to the extent it can be prevented) by practicing safe sex and avoiding sharing needles for intravenous drug use. However, an HIV-positive person can still prevent HIV dementia by going on a regimen of antiretroviral therapy. The number of cases of HIV dementia have been greatly reduced as more effective antiretroviral therapies have been developed.

Other than starting to use anti-HIV drugs as early as possible and following the doctor’s prescriptions, one can reduce one's risk by avoiding comorbid conditions like hepatitis C infection.