A prospective comparison of neuropsychologic function in HIV-seropositive and seronegative methadone-maintained patients.

A prospective longitudinal study of neuropsychological and psychosocial functioning in a methadone-maintained population was initiated to test the hypothesis that cognitive impairments may be present early in the course of HIV infection, before the onset of other physical symptoms. A total of 220 methadone-clinic patients without evidence of HIV-related illnesses were given baseline psychological screening tests, as well as serological testing for HIV antibodies. At baseline, 83 (38%) had antibodies to HIV and 137 (62%) did not. On initial testing, controlling for race/ethnicity, age, sex and drug use, the seropositives were more cognitively impaired than the seronegatives. The differences were statistically significant for three subtests on univariate analysis: finger tapping (dominant), digit span (forward) and similarities. Ninety-one patients whose current serological status was known were given follow-up neuropsychological and psychosocial assessments after a mean interval of 7.4 months from baseline testing. At follow-up, seropositives continued to be more cognitively impaired than seronegatives, but there was no deterioration in the performance of the initial seropositives over the time interval.