I have a dear friend with advanced AIDS. He lives in continuous fear of getting AIDS-related dementia. What are the symptoms? Where can I get more information on the subject of this dementia?

G.L.

Mental decline associated with HIV (the virus that causes AIDS) is one of the most feared complications of the infection. Cognitive (thinking) impairment in people with HIV has many possible causes: tumors or infections, side effects of medications, depression, alcohol abuse and stroke. HIV infection, by itself, also can cause cognitive decline, a syndrome referred to by most authorities as HIV dementia. Dementia is a general term for a decline in a person's intellectual function. Demented patients are awake and alert; they just have varying degrees of cognitive impairment.

HIV dementia can occur at any stage of HIV infection, but significant abnormalities most often occur in the later stages. Like most forms of dementia, it appears gradually. Early on, the affected person may have some difficulty concentrating and be less able to handle complex tasks. As the condition progresses, he or she may lose the ability to perform simpler tasks such as reading. Irritability, violent behavior and other personality changes often occur. Patients often lose coordination and find walking difficult. Remember, as with any other illness, not all patients are affected in the same way and not all people progress at the same rate.

There is no good treatment for HIV dementia. One study showed that high doses of AZT, or zidovudine (Retrovir), can improve cognitive performance. AIDS experts hope the current drugs used to treat HIV, especially the protease inhibitors, will be helpful for patients with this condition, though there are no good studies documenting such benefit. There are many anecdotal reports of patients who make excellent recovery after receiving various anti-HIV treatments. In my own experience, I have treated several patients with HIV dementia who went on to improve greatly. One patient who had been diagnosed with advanced HIV dementia improved to such an extent that he went back to work. Studies are under way to determine whether drugs used for Alzheimer's disease can help patients with HIV dementia. While these treatments are not expected to cure the condition, they may be helpful in diminishing some of the symptoms.