LONG-TERM ZIDOVUDINE REDUCES NEUROCOGNITIVE DEFICITS IN HIV-1 INFECTION

Objective: To determine the efficacy of zidovudine (ZDV) in preventing decline of neurocognitive functions in HIV-1 infection. Design: Retro spective evaluation of subjects enrolled in a natural history study. T wo analyses were made to evaluate the effect of (1) current ZDV, irres pective of length of treatment and (2) long-term ZDV treatment for at least 1 year. Setting: Subjects were recruited from HIV out-patient cl inics. Patients: HIV-1-seropositive subjects were assigned to one of t hree groups according to the Centers for Disease Control and Preventio n classification: asymptomatic infection (n=60), symptomatic infection but without AIDS (n=51), and AIDS (n=32). Main outcome measures: Stan dardized neuropsychological and neurophysiological measures [electroen cephalogram (EEG) and long-latency evoked potentials]. Results: Long-t erm ZDV use was associated with improved cognitive performance in subj ects with early symptomatic HIV-1 infection and AIDS, compared to subj ects in the same clinical stage but without previous ZDV treatment. Th is was corroborated by neurophysiological evidence of reduced slow-wav e EEG amplitude in the ZDV-treated subjects. The advantage of ZDV trea tment was evident despite lower immune status in most treated subjects . Conclusions: The findings in this natural history study indicate tha t long-term ZDV treatment may be an effective prophylactic to reduce n eurocognitive deficits in symptomatic HIV-1 infection, thereby lowerin g the risk for developing HIV-1-associated dementia.