Research
Antiretroviral Therapy

Investigator: Eileen Martin, Ph.D.

Dementia is common in advanced HIV-1 disease and patients with less advanced infection often experience mild mental slowing and difficulty with concentration. Zidovudine crosses the blood-brain barrier and clinical and laboratory indices of HIV-1 infection of the CNS improve following initiation of zidovudine therapy. Patients' performance of standard clinical neuropsychological tests improve following initiation of zidovudine therapy, but these tests are not sensitive to minor HIV-related neurocognitive deficits and are difficult to interpret when administered to patients with limited education or a history of substance abuse

In a series of publications, Drs. Martin and Pursell and their colleagues have shown that computerized reaction time (RT) tasks are more sensitive to HIV-related cognitive deficits than standard clinical tests and thus are appropriate for evaluating patients with a wider range of disease severity, require less time to administer and can be performed reliably by patients with varying levels of education or a positive substance abuse history.

The current project is a longitudinal pilot study of reaction times of 30 HIV-seropositive patients on combination antiretroviral therapy with zidovudine and lamivudine. Lamivudine appears to slow the development of zidovudine resistance and patients treated with lamivudine in combination with zidovudine may show more pronounced or longer-duration neurologic benefits. The purpose of this pilot study is to determine if patients on zidovudine-lamivudine combination therapy show a detectable decrease in reaction times, which would suggest that antiretroviral treatment results in improved neurocognitive functioning; and to correlate changes in reaction time performance with changes in viral activity and viral load.