Neurologic abnormalities in schizophrenic patients and their families. I. Comparison of schizophrenic, bipolar, and substance abuse patients and normal controls.

The prevalence of neurologic abnormalities detectable on standard clinical examination by neurologists blind to diagnosis was compared for DSM-III-diagnosed, age- and sex-matched groups consisting of 24 schizophrenic (SCZ) patients, 24 patients with bipolar affective disorder (MDI) with history of psychosis, 24 patients hospitalized for alcohol or other drug abuse (D/A), and 24 normal volunteers (NL). The SCZ group had significantly more total abnormalities than the other three; both the MDI and D/A groups in turn had more total abnormalities than normal controls. After exclusion of findings due to medication or otherwise unrelated to the pathogenesis of psychiatric illness, only the SCZ-NL, SCZ-MDI, and D/A-NL differences remained significant. When neurologic abnormalities were further restricted to those indicating localized dysfunction of the corticospinal tracts, basal ganglia, or cerebellum, the only two persistent significant differences were between SCZ-NL and SCZ-MDI groups.