Schizophrenic outcome in late life: symptom state and platelet monoamine oxidase activity.

Reported here are the results of a study of symptom state, platelet monoamine oxidase (MAO) activity, and demographic variables in a group of elderly neuroleptic-free schizophrenics. Analyzed by both bivariate and multivariate techniques, the data from this sample indicate that after the effects of demographic variables upon the variance of enzyme activity have been controlled for, the patients most likely to continue to manifest schizophrenic symptomatology in the senium are those with low platelet MAO activity. The results are discussed with respect to other studies of platelet MAO and prognosis in schizophrenia and with respect to future studies.