Homovanillic acid in the cerebrospinal fluid: patterns of response after four weeks of neuroleptic treatment.

Lumbar cerebrospinal fluid (CSF) homovanillic acid (HVA) concentrations were measured before and after 4 weeks of neuroleptic treatment in schizophrenic (n = 15) and schizoaffective (n = 4) patients. Neuroleptic treatment induced a nonsignificant (17%) increase in CSF HVA group mean levels. For the total group, no correlations were found between pretreatment CSF HVA and clinical measures, or between changes in HVA and clinical response. An alternative interpretation was attempted by defining "tolerant" and "nontolerant" subgroups. A "tolerant" response was defined as a reduction in posttreatment HVA values below pretreatment levels, whereas a "nontolerant" response was characterized by posttreatment values above pretreatment levels. When thus defined, nontolerant patients had a significantly inferior clinical response to neuroleptics, in contrast to their tolerant counterparts. Further, although there was no difference in pretreatment CSF HVA values between these two groups, pretreatment clinical profiles did differ significantly. Also, in a retrospective analysis, nontolerant patients were found to have a significantly earlier age of illness onset, a greater number of prior psychiatric hospitalizations, and more time spent in psychiatric hospitals.