Academic Biography

Dr. David Mamo is a Staff Psychiatrist at the Centre for Addiction and Mental Health and assistant professor in the Schizophrenia Department of Psychiatry at the University of Toronto and the Centre for Addiction and Mental Health.  His research focus is to optimize the use of available antipsychotic medications to treat schizophrenia, and he uses a combination of clinical and brain imaging studies to find new therapies for treating schizophrenia. 

What is Schizophrenia?

Schizophrenia is a chronic psychiatric disorder characterized by abnormal perception of reality.  There are many possible symptoms, which vary from person to person.  Common symptoms include disorganized speech and thinking, hallucinations, and delusions.  Schizophrenia affects up to 1% of people in their lifetime, with onset typically occurring in the late teens to early 20’s.  While treatment is available for schizophrenia, it is not always effective.  Individuals with schizophrenia are also likely to be diagnosed with depression and anxiety disorders – 10% commit suicide. 

Project Summary

With this grant, Dr. Mamo and his team are conducting a clinical study to investigate whether patients diagnosed with schizophrenia who are taking more than one prescribed antipsychotic medication at a time (polypharmacy) can switch to taking one prescribed antipsychotic medication (monopharmacy) and continue to experience the same mental health benefits. 

Over the course of this clinical study, Dr. Mamo and his team will regularly monitor the clinical symptoms of 100 participants from the Schizophrenia Program at the Centre for Addiction and Mental Health (CAMH) who have been on polypharmacy for schizophrenia for at least 30 days prior to the experiment.  The participants will be randomly assigned to two groups.  Half of the participants will continue to take one of their prescribed medications and will take a placebo in place of their other medication.  The other half of the participants will receive both of their prescribed medications, but one of these medications will be disguised to look like a placebo. 

The participants and Dr. Mamo’s team will not know which group each participant is in.  This experimental set up is called a double-blind experiment.  The results of double-blind experiments are less likely to be influenced by reports of what a participant or researcher thinks they should find.  After all participants have completed the study statistical methods will be used to evaluate whether there is any significant improvement or deterioration in the clinical symptoms of schizophrenia for patients in the two groups.

Background and Rationale

Antipsychotic medications are prescribed to relieve the clinical symptoms of schizophrenia and related disorders.  The majority of patients who take antipsychotic medications continue to experience unpleasant clinical symptoms and up to a third do not benefit from their prescribed medication.  There are many different medications that are classified as antipsychotics and a doctor and patient can choose to try other prescriptions to achieve the desired effect.  However, some doctors choose to prescribe patients who have not achieved satisfactory relief from their clinical symptoms a combination of two or more antipsychotic medications.  Approximately one-third to half of patients diagnosed with schizophrenia or related mental diseases receive more than one antipsychotic medication. 

Prescribing more than one antipsychotic medication to a patient is not supported by current recommendations, and is not backed by a substantial body of psychological research.  Polypharmacy does not necessarily improve a patient’s symptoms.  It does, however, increase medical expenses, and increase the risk of negative drug-drug interactions and side effects.  Some studies even link polypharmacy to increased duration of hospitalization and increased mortality.  Moreover, studies show that patients who are prescribed more than one antipsychotic medication for 30 days are likely to continue on that combination.

Outcome

Dr. Mamo and his team are in the process of conducting clinical studies with participants and are seeking more people to join their clinical study. 

This is the first project to investigate the effectiveness of treating people diagnosed with schizophrenia with more than one antipsychotic that uses a placebo-controlled design.  The results of this clinical study will guide doctors in making appropriately informed decisions regarding the use of multiple antipsychotic medications for treating schizophrenia.