The effect of antipsychotic medication on neuromotor abnormalities in neuroleptic-naive nonaffective psychotic patients: a naturalistic study with haloperidol, risperidone, or olanzapine.

OBJECTIVE: To examine the effect of antipsychotic medication on neuromotor abnormalities in a sample of psychotic patients never exposed to antipsychotic drugs.
METHOD: One hundred psychotic patients were assessed (from January 1998 to December 2002) using DSM-IV criteria for parkinsonism, dyskinesia, akathisia, catatonia, and dystonia at baseline and after 4 weeks of treatment with haloperidol (n = 23), risperidone (n = 52), or olanzapine (n = 25). We examined change scores in neuromotor ratings over the treatment period across treatment groups and rates of drug-responsive and drug-emergent neuromotor syndromes in patients with and without preexisting neuromotor abnormalities.
RESULTS: Overall time effects revealed a worsening of parkinsonism (P = .002) and akathisia (P = .002) ratings and an improvement of dyskinesia (P = .001) and catatonia (P < .001) ratings. Main treatment effects revealed that patients taking haloperidol had a significant mean increase in akathisia scores compared with those of patients taking risperidone (P = .002) or olanzapine (P < .001). A significantly greater percentage of olanzapine-treated patients experienced remission of preexisting parkinsonism than did the other treatment groups (P = .047). Patients without preexisting motor abnormalities were more likely to experience drug-emergent parkinsonism if they were treated with haloperidol or risperidone than with olanzapine (P = .001) and were more likely to experience drug-emergent dystonia (P = .014) and akathisia (P = .013) if they were treated with haloperidol than with risperidone or olanzapine.
CONCLUSIONS: The relationship between antipsychotic medication and neurologic abnormalities is more complex than previously acknowledged since antipsychotic drugs may both improve preexisting abnormalities and cause "de novo" neurologic syndromes. Overall, olanzapine has a more favorable neuromotor profile than risperidone, which in turn has a more favorable profile than haloperidol.