Movement disorders in patients treated with long-acting injectable antipsychotic drugs

Abstract

The frequencies of antipsychotic drug-induced movement disorders documented by physicians and identified by researchers using standardized clinical rating scales were compared, as were the frequencies associated with use of fluphenazine decanoate and haloperidol decanoate. All outpatients at a Veterans Affairs medical center who were being maintained with intramuscular injections of fluphenazine decanoate or haloperidol decanoate and were in otherwise good health were studied. The patients were assessed by a pharmacist using the Abnormal Involuntary Movement Scale to evaluate the presence and severity of tardive dyskinesia (TD) and the Simpson-Angus EPS Rating Scale to evaluate the presence and severity of extrapyramidal symptoms (EPS). The patients' medical records for the previous two years were reviewed to determine whether a movement disorder had been documented, whether the patient's informed consent for antipsychotic drug use had been obtained, and to collect other data about the patient and his or her drug therapy. A total of 50 patients were evaluated. A neurologic examination by a physician had been documented in the chart within six months before clinical testing for 36 patients; abnormal movements had been found in 8 patients. Twenty-one subjects met the study criteria for probable TD or EPS or both. Of these patients, only six had been identified within the previous six months as having a movement disorder. Two patients with medical-record documentation of a movement disorder were not so identified by their test scores. Informed consent had been obtained from only 10 patients. Patients receiving haloperidol decanoate had a higher frequency of EPS but were also receiving higher drug dosages than patients given fluphenazine decanoate.(ABSTRACT TRUNCATED AT 250 WORDS)