title: Clozapine response and pre-treatment EEG-is there some kind of relationship.
abstract: BACKGROUND
  Clozapine has been used widely in the management of treatment-resistant schizophrenia. The present study aims at determining whether pre-treatment electroencephalography (EEG) abnormalities would serve as a marker for response to clozapine treatment.
  
  
  METHODS
  This was a cross-sectional study done in a tertiary care center in Mumbai where patients diagnosed with schizophrenia using DSM-IV criteria and resistant schizophrenia using Kane criteria were assessed using EEG prior to starting clozapine treatment. They were rated for symptomatic improvement using the Positive and Negative Syndrome Scale (PANSS) along with Clinical Global Improvement for Severity (CGI-S). The results were statistically analysed and presented.
  
  
  RESULTS
  55 out of the 80 patients in the study showed baseline EEG abnormalities. The mean duration of illness in the patients were 2.65 years. Slow wave and background EEG abnormalities were common in pre-treatment EEG. 36.4% patients in the study showed clinical response. Patients with negative symptoms and baseline EEG abnormalities showed better response.
  
  
  CONCLUSIONS
  The study was circumscribed and had many limitations due to a small sample size. The relation between pre-treatment EEG abnormalities and clozapine response could not be statistically correlated and it could not be ascertained to be a marker for response to clozapine therapy.
authors.affiliation: Department of Psychiatry, Elgin Early Intervention Program for Psychosis, The University of Western Ontario, Ontario, Canada ; Mental Health Resource Foundation, Mumbai, Maharashtra, India.
authors.forename: Amresh
authors.initials: A
authors.lastname: Shrivastava
authors.affiliation: Department of Psychology, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Megan
authors.initials: M
authors.lastname: Johnston
authors.affiliation: Department of Psychiatry, Lokmanya Tilak Municipal Medical College, Mumbai, Maharashtra, India.
authors.forename: Nilesh
authors.initials: N
authors.lastname: Shah
authors.affiliation: Department of Epidemiology and Biostatistics, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada.
authors.forename: Larry
authors.initials: L
authors.lastname: Stitt
authors.affiliation: Department of Psychiatry, Lokmanya Tilak Municipal Medical College, Mumbai, Maharashtra, India.
authors.forename: Shivanshu
authors.initials: S
authors.lastname: Shrivastava
authors.affiliation: Department of Psychiatry, Lokmanya Tilak Municipal Medical College, Mumbai, Maharashtra, India.
authors.forename: Avinash De
authors.initials: AD
authors.lastname: Sousa
keywords: Clozapine; electroencephalography; electroencephalography abnormalities; schizophrenia; treatment resistant schizophrenia