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Anticholinergic Burden in Schizophrenia

This study has been terminated.
(Insufficient subject accrual)
Information provided by (Responsible Party):
Ariel Graff, Centre for Addiction and Mental Health Identifier:
First received: July 11, 2008
Last updated: August 21, 2015
Last verified: August 2015
Anticholinergic antiparkinsonian agents often cause side-effects including cognitive impairment, dry mouth, and constipation while they diminish antipsychotic-induced parkinsonian symptoms. The introduction of second generation antipsychotics (SGA) brought fewer neurological side effects. However, anticholinergic coprescription rates are still as high as 12-65% in patients on SGA that are much higher than the incidence of EPS reported in clinical trials (3-20%). This apparently discrepancy is likely explained, in part, by the established tradition of routine use of this medications. Older patients are particularly sensitive to anticholinergic side-effects due to age-related changes in pharmacokinetics and pharmacodynamics. In this study, we will examine the safety and benefits of reducing the dose of a frequently prescribed anticholinergics, benztropine, on cognitive function, extrapyramidal symptoms, and psychotic symptoms in older subjects with a primary psychotic disorder.

Condition Intervention
Schizophrenia Schizoaffective Disorder Schizophreniform Disorder Delusional Disorder Psychotic Disorders Drug: Benztropine

Study Type: Interventional
Study Design: Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Anticholinergic Burden in Schizophrenia

Resource links provided by NLM:

Further study details as provided by Ariel Graff, Centre for Addiction and Mental Health:

Primary Outcome Measures:
  • percentage of participants who successfully withdraw from anticholinergic antiparkinsonian agents. [ Time Frame: at the end of the study ]

Secondary Outcome Measures:
  • effect of reducing the dose of benztropine on EPS and anticholinergic side-effects including cognitive impairments. [ Time Frame: intermittent ]

Enrollment: 2
Study Start Date: June 2007
Study Completion Date: December 2011
Primary Completion Date: December 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: 1 Drug: Benztropine
Patients aged ≥ 50 years suffering from a primary psychotic disorder treated with a SGA and benztropine concomittantly at any dose steadily for at least 3 months will be eligible to participate in this study. The dose of benztropine will be reduced by 0.5mg per week. During this 8-week study period, extrapyramidal symptoms will be assessed on a weekly basis. The clinical assessments will be repeated 8 weeks after the initial assessments.

  Show Detailed Description


Ages Eligible for Study:   50 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Age of 50 and older
  • DSM-IV/SCID diagnosis of schizophrenia, schizoaffective disorder, schizophreniform disorder, delusional disorder, or psychotic disorder NOS
  • Having been treated with benztopine at a steady daily dose of 3 mg or less for at least three months
  • Having been treated with risperidone, quetiapine, olanzapine, or clozapine at a steady dose for at least two weeks.
  • Willingness to provide consent for investigator to communicate with their physician of record regarding their participation in the study.

Exclusion Criteria:

  • Unstable physical illness or clinically significant neurological disorder
  • A history of severe or life-threatening dystonia
  • Presence of EPS defined as a total score of 7 or more or a score of 3 or more on any individual item on the SAS at baseline
  • Positive urine drug screen for illegal drugs
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00715377

Canada, Ontario
Centre for Addiction and Mental Health
Toronto, Ontario, Canada, M5T 1R8
Sponsors and Collaborators
Centre for Addiction and Mental Health
Principal Investigator: Ariel Graff, MD Centre for Addiction and Mental Health
  More Information

Additional Information:
Responsible Party: Ariel Graff, Principal Investigator, Centre for Addiction and Mental Health Identifier: NCT00715377     History of Changes
Other Study ID Numbers: 118/2007
Study First Received: July 11, 2008
Last Updated: August 21, 2015

Keywords provided by Ariel Graff, Centre for Addiction and Mental Health:
Anticholinergic antiparkinsonian agents
elderly population

Additional relevant MeSH terms:
Psychotic Disorders
Mental Disorders
Schizophrenia, Paranoid
Pathologic Processes
Schizophrenia Spectrum and Other Psychotic Disorders
Cholinergic Antagonists
Cholinergic Agents
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Physiological Effects of Drugs
Antiparkinson Agents
Anti-Dyskinesia Agents
Autonomic Agents
Peripheral Nervous System Agents
Muscarinic Antagonists
Dopamine Uptake Inhibitors
Neurotransmitter Uptake Inhibitors
Membrane Transport Modulators
Dopamine Agents processed this record on July 19, 2017