title: Extrapyramidal Symptoms During Risperidone Maintenance Treatment in Schizophrenia: A Prospective, Multicenter Study.
abstract: The risperidone maintenance treatment in schizophrenia study was designed to identify the duration of maintenance treatment required with an initial therapeutic dose in contrast to reducing the dose over time. This study investigated extrapyramidal symptoms (EPSs) in different risperidone maintenance treatment paradigms over 1 year. Clinically stabilized patients with schizophrenia (n = 374) were randomized to a no-dose-reduction group and 4-week and 26-week reduction groups, in which the dose was gradually reduced by 50% over 8 weeks and maintained. Extrapyramidal symptoms were assessed at baseline and monthly for 6 months, followed by every 2 months. The Simpson-Angus Scale of Extrapyramidal Symptoms-Chinese version assessed EPS severity. Data were analyzed by a generalized linear mixed model (GLMM). The frequency of EPS at baseline was 23.2%, 20.0%, and 21.3% in the 4-week, 26-week, and no-dose-reduction groups, respectively. Risperidone dosage, positive symptoms, and disorganized thoughts at baseline predicted development of EPS. The GLMM indicated that a significant decrease in EPS was maintained, and different trajectories occurred over time across groups. In the 235 patients who continued treatment after 1 year, the incidence of EPS decreased to 4.1%, 2.8%, and 10.0% in the 4-week, 26-week, and no-dose-reduction groups, respectively, whereas the numbers of dropouts because of intolerable EPS were not significantly different (4.8%, 6.7%, and 6.2%, respectively). These novel findings indicate EPSs were tolerable and differentially decreased depending on the dose paradigm during the 1-year treatment period. Future studies should implement a GLMM to investigate antipsychotic adverse effects during long-term treatment.
authors: From the *Beijing Key Laboratory of Mental Disorders, Department of Psychiatry, Beijing Anding Hospital, Capital Medical University; and †Center of Schizophrenia, Beijing Institute for Brain Disorders, Laboratory of Brain Disorders (Capital Medical University), Ministry of Science and Technology, Beijing, China.
authors: Qi-Jing
authors: QJ
authors: Bo
authors: Xian-Bin
authors: XB
authors: Li
authors: Zhi-Min
authors: ZM
authors: Wang
authors: An-Ning
authors: AN
authors: Li
authors: Xin
authors: X
authors: Ma
authors: Chuan-Yue
authors: CY
authors: Wang
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects*; D001480:Basal Ganglia Diseases / Q000139:chemically induced* / Q000453:epidemiology*; D004334:Drug Administration Schedule; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018967:Risperidone / Q000009:adverse effects*; D012559:Schizophrenia / Q000188:drug therapy* / Q000453:epidemiology*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D014150:Antipsychotic Agents; D018967:Risperidone