Decreased homovanilic acid in cerebrospinal fluid correlates with impairedneuropsychologic function in HIV-1-infected patients

To determine whether dopamine metabolism is abnormal in HIV infected patien ts and whether dopamine metabolism abnormalities are related to specific ne uropsychologic characteristics in HIV-infected patients, we measured cerebr ospinal fluid (CSF) levels of homovanilic acid (HVA), the primary dopamine metabolite, in 10 HIV-infected patients and compared it to HVA levels in CS F in a group of 13 healthy control subjects. HIV-infected patients were als o assessed with a battery of neuropsychologic tests and HVA levels were the n correlated with performance on specific neuropsychologic tests. The mean (+/-SD) HVA level in CSF was 100.9 +/- 29.3 nmol/L in the HIV-infected stud y group and 230.5 +/- 50.0 nmol/L in the non-HIV-infected control group (p < 0.0001). The decrease in concentrations of HVA in CSF correlated with imp airment on performance on neuropsychologic testing (Spearman r = 0.67; p = 0.03). When the relationship between HVA levels and specific cognitive doma ins was evaluated, we observed trends for positive correlation between HVA levels and tests that measure motor speed (r = 0.59; p = 0.074) and those t esting attention, concentration, and executive control (r = 0.54; p = 0.108 ). There was no relationship between performance on memory tests and CSF HV A levels (r = -0.0061; p = 0.987). These results further support the hypoth esis that dopaminergic dysfunction plays an important role in the pathogene sis of AIDS dementia complex (ADC) and suggest that specific motor and cogn itive abnormalities may be related to depressed dopaminergic activity. This may have important implications for the development of treatments or preve ntive strategies for ADC.