Dementia

Dementia is a brain disorder that makes it hard for  a person to think clearly and do daily tasks. Dementia happens most often in the late stage of AIDS, when the body is fighting many infections at the same time. 

Symptoms

AIDS dementia complex -- dementia caused by HIV infection – causes changes in a person’s:

• Ability to understand, process and remember information (cognition)
• Behavior
• Coordination
• Emotions or mood

It is easy to mistake signs of dementia for those of depression, drug side effects or opportunistic infections like toxoplasmosis or lymphoma. One person may experience mild symptoms while another person may have severe symptoms.

Symptoms of dementia may include:

• Memory loss
• Speech problems
• Poor concentration
• Poor judgment
• Taking longer to do complicated tasks
• Slowed thinking, eating or writing
• Not being able to do common activities of daily living
• Loss of bladder or bowel control
• Loss of feeling in and control of the legs
• Stiff, awkward or slowed movements
• Unsteady walking and balance
• Changes in handwriting
• Muscle weakness
• Difficulty holding objects
• Emotional changes such as irritability, apathy, withdrawal, depression, personality changes or excitability

Causes

Usually nerve or brain disorders are due to the death of nerve cells. HIV doesn’t directly infect nerve cells. HIV may either infect or disturb cells (macrophages and microglia) that nurture and maintain the brain. The infected macrophages and microglia then produce toxins that set off a chain reaction that kill neurons (brain cells). 

Risk Factors

AIDS-related dementia usually develops after years of HIV infection. It is linked to low CD4+ cells and high viral loads.

Dementia occurs more often in children with HIV than with adults. In children, dementia has similar signs but gets worse faster.

Prevention

Using highly active antiretroviral therapy (HAART) helps prevent or delay dementia. HAART may also improve mental function in people who already have dementia. 

Diagnosis

Diagnosing dementia can be difficult. It is important to rely on experienced doctors. Specialists such as psychiatrists and neurologists may be needed if the symptoms aren’t clear.

One important goal of diagnosing dementia is to rule out other possible causes of symptoms. These include depression, strokes, brain tumors, diabetes, low hormone levels, toxoplasmosis, progressive multifocal leukoencephalopathy (PML) or lymphoma.

Several tests are done to diagnose dementia complex:

• A mental status exam. This helps pinpoint memory loss and problems of concentration and abstract thinking as well as mood swings.
• Computed tomography (CT) or magnetic resonance imaging (MRI) scans. CT scans can show signs of destroyed brain tissue. An MRI may be done if the CT scan is not clear. Both can help rule out other conditions that might be causing the symptoms.
• A spinal tap. This test removes some of the fluid that surrounds the brain and spinal cord to look at under a microscope.
• Electroencephalography (EEG). This records the electrical activity of the brain. People with late stage dementia usually have slower brain activity. An EEG also is used to see whether a person is having seizures.

No lab test can confirm dementia. Lab tests can, however, rule out conditions that might cause similar symptoms. 

Treatment

HAART, which helps control HIV infection, also protects many HIV-positive people from developing dementia. In some cases, HAART can partly or entirely reduce symptoms of dementia.

Drugs that cross the blood-brain barrier are helpful. They include: AZT, d4T (stavudine, Zerit), abacavir (Ziagen), nevirapine (Viramune), amprenavir (Agenerase) and to a lesser degree indinavir (Crixivan) and 3TC (lamivudine, Epivir).

Depression and behavioral disturbances can sometimes be helped with drug therapy. These include antidepressants or antipsychotics. (Antipsychotics help improve agitation, aggression, hallucinations or delusions.)

A doctor has to balance HAART with drugs to treat dementia. Sometimes these drugs interact badly when taken together.

A person with dementia needs to:

• Stay active. Daily exercise helps the brain work better. It also reduces depression and anxiety.
• Challenge the mind. Working puzzles, games, reading and safe hobbies and crafts are like exercise for the brain.
• Stay socially active. See friends and relatives. This keeps the mind active and emotions balancef.
• Eat a balanced, nutritious diet with plenty of fruits and vegetables. This helps keep weight at a healthy level. It also prevents malnutrition and constipation.
• Give up smoking or using tobacco products. The nicotine in tobacco cuts down the flow of blood through the body. Smoking can be dangerous for someone who is forgetful or can’t concentrate.