title: Blood lactate levels as a biomarker of antipsychotic side effects in patients with schizophrenia.
abstract: BACKGROUND
  Antipsychotic drugs (APs) are widely prescribed in psychiatry primarily for the treatment of psychosis in schizophrenia and bipolar disorders. An issue related to poor prognosis in patients with chronic illness relates to the accumulation of lactate levels in blood, leading to patients that become critically ill. It is suggested that haloperidol and olanzapine, as common therapy for schizophrenia, are associated with increased levels of blood lactate, which may contribute towards the extra-pyramidal side effects.
  
  
  OBJECTIVE
  In this study, 88 patients attending the psychiatry outpatient clinic of Mansoura University Hospital, under treatment with typical APs (chlorpromazine or haloperidol) or the atypical APs (risperidone, olanzapine or quetiapine) were followed over a three-month period. Blood lactate levels were assessed at diagnosis, ten days and 90 days after the start of AP treatment. Extra-pyramidal symptoms (EPSs) were studied in participants during the course of this study.
  
  
  RESULTS
  Chlorpromazine and haloperidol caused significant increases in lactate levels within the first ten days of therapy, while after 90 days, all APs showed significant increases in arterial blood lactate levels in comparison with the first baseline measurement (for all APs, p-values <0.0001). Dystonia was reported by patients on chlorpromazine, haloperidol and risperidone therapies, while Parkinsonian-like manifestations were reported with all APs tested except for quetiapine. Both dystonia and Parkinsonian-like manifestations were also observed alongside the significant increases in arterial blood lactate levels in comparison to patients on therapy not displaying EPSs.
  
  
  CONCLUSIONS
  These findings suggest elevated blood lactate levels may serve as early biomarkers for occurrence of extra-pyramidal symptoms in patients on chronic APs treatment.
authors.affiliation: Department of Forensic Medicine and Clinical Toxicology, Faculty of Medicine, Mansoura University, Mansoura, Egypt.
authors.forename: Ekramy
authors.initials: E
authors.lastname: Elmorsy
authors.affiliation: Psychiatry department, Faculty of Medicine, Mansoura University, Mansoura, Egypt.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Shahda
authors.affiliation: Psychiatry department, Faculty of Medicine, Mansoura University, Mansoura, Egypt.
authors.forename: El-Hassanen M
authors.initials: el-HM
authors.lastname: Mahmoud
authors.affiliation: Clinical Pathology department, Faculty of Medicine, Mansoura University, Mansoura, Egypt.
authors.forename: Shirien A
authors.initials: SA
authors.lastname: Rakha
authors.affiliation: Institute of Neuroscience, Medical School, Newcastle University, Newcastle upon Tyne, UK mohammed.shoaib@newcastle.ac.uk.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Shoaib
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D015415:Biomarkers / Q000097:blood; D001714:Bipolar Disorder / Q000188:drug therapy; D016022:Case-Control Studies; D004409:Dyskinesia, Drug-Induced / Q000097:blood / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D019344:Lactic Acid / Q000097:blood*; D008297:Male; D012559:Schizophrenia / Q000188:drug therapy*; D055815:Young Adult
chemical_list: D014150:Antipsychotic Agents; D015415:Biomarkers; D019344:Lactic Acid
keywords: Neuroleptic; Parkinsonian-like; atypical; dystonia; typical