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Double-Blind Trial of a Probiotic Supplement to Reduce the Symptoms of Schizophrenia

This study has been completed.
Stanley Medical Research Institute
Information provided by (Responsible Party):
Faith Dickerson, PhD, MPH, Sheppard Pratt Health System Identifier:
First received: November 16, 2010
Last updated: January 7, 2014
Last verified: January 2014
The investigators intend to explore the hypothesis that symptoms of schizophrenia may be reduced by the administration of a probiotic supplement when used in addition to standard antipsychotic medications.

Condition Intervention
Schizophrenia Schizoaffective Disorder Dietary Supplement: Probiotic Supplement Dietary Supplement: Identical-appearing Placebo

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: A Double-Blind Placebo-Controlled Trial of a Probiotic Supplement to Reduce the Symptoms of Schizophrenia

Resource links provided by NLM:

Further study details as provided by Faith Dickerson, PhD, MPH, Sheppard Pratt Health System:

Primary Outcome Measures:
  • Change in Positive and Negative Syndrome Scale (PANSS) Score From the Start to the End of the Double-blind Treatment Phase (Week 0 to Week 14) [ Time Frame: 14 weeks (week 0 to week 14) ]
    The Positive and Negative Syndrome Scale (PANSS) measures psychiatric symptomatology, especially related to psychosis. The complete PANSS contains ratings for 30 symptoms, including 7 positive symptoms, 7 negative symptoms, and 16 general psychiatric symptoms. The severity of each symptom is rated on a scale ranging from 1 (minimal) to 7 (extreme); higher scores indicate increased symptomatology. Total PANSS scores include scores from all categories and range from 30 to 210 units on a scale.

Secondary Outcome Measures:
  • Gastrointestinal Functioning From the Beginning to the End of the Double-blind Treatment Phase Weeks 0-14 [ Time Frame: 14 weeks (weeks 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 & 14) ]
    Self report rating of difficulty moving bowels on a 4 point scale from "no difficulty" to "severe difficulty"

  • Measurement of Gliadin and Casein Antibody Levels [ Time Frame: 16 weeks (baseline prior to placebo run in to week 14) ]

Enrollment: 65
Study Start Date: August 2010
Study Completion Date: August 2012
Primary Completion Date: August 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Probiotic Supplement
Probiotic supplement 1 tablet by mouth daily for 14 weeks after 2 week placebo run-in
Dietary Supplement: Probiotic Supplement
Probiotic Supplement 1 tablet by mouth daily
Placebo Comparator: Identical-appearing Placebo
Identical appearing placebo 1 tablet by mouth daily for 14 weeks after 2 week placebo run-in
Dietary Supplement: Identical-appearing Placebo
Probiotic identical placebo 1 tablet by mouth daily

Detailed Description:

The primary aim of the current study is:

  1. To evaluate the safety and efficacy of a supplemental probiotic therapy, containing the microorganisms Lactobacillus rhamnosus GG and Bifidobacterium lanimalis subsp. lactis (BB12), for individuals with schizophrenia who have residual psychotic symptoms of at least moderate severity.

    Secondary aims of the study are:

  2. To assess the effect of probiotic treatment on patients' gastrointestinal functioning
  3. To study the effect of probiotic treatment in lowering the levels of antibodies to casein and gliadin.
  4. To investigate the association between the efficacy of probiotic therapy and initial levels of antibodies to gliadin and casein.

Ages Eligible for Study:   18 Years to 65 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Age 18-65.
  • Capacity for written informed consent.
  • Primary Axis I diagnosis (DSM-IV) of schizophrenia, any type, OR schizoaffective disorder (APA, 1994).
  • Currently an outpatient at the time of enrollment.
  • Residual psychotic symptoms which are at least moderately severe as evidenced by one or more PANSS positive symptom scores, and/or PANSS negative symptom scores of 4 or more; OR a total PANSS score of 50 or more, containing at least three positive or negative items with scores of 3 or more at screening.
  • Conformance to PORT Treatment Recommendation re Maintenance Antipsychotic Medication Dose (Buchanan et al., 2010).
  • Receiving antipsychotic medication for at least 8 weeks prior to starting the study with no medication changes within the previous 21 days.
  • Proficient in the English language.

Exclusion Criteria:

  • Diagnosis of mental retardation.
  • Any clinically significant or unstable medical disorder as determined by the investigators, including congestive heart failure, abnormal liver function or disease, renal failure, acute pancreatitis, any diagnosis of cancer undergoing active treatment, HIV infection or other immunodeficiency condition.
  • History of IV drug use.
  • Primary diagnosis of substance abuse or dependence according to DSM-IV criteria within the last three months.
  • Participated in any investigational drug trial in the past 30 days.
  • Pregnant or planning to become pregnant during the study period.
  • Receipt of antibiotic medication within the previous 14 days (as anaerobic organisms residing in the gastrointestinal tract may be minimally affected by antibiotics).
  • Documented celiac disease (as such persons should be on a gluten-free diet as this is the standard care).
  • Of note, the investigators are not limiting the study to individuals with elevated levels of gliadin or casein antibodies as the investigators intend to look at these levels as a predictor of response.
  Contacts and Locations
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Please refer to this study by its identifier: NCT01242371

United States, Maryland
Sheppart Pratt Health System
Towson, Maryland, United States, 21204
Sponsors and Collaborators
Sheppard Pratt Health System
Stanley Medical Research Institute
Principal Investigator: Faith B Dickerson, PhD, MPH Sheppard Pratt Health System
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Faith Dickerson, PhD, MPH, Head, Stanley Research Program, Sheppard Pratt Health System Identifier: NCT01242371     History of Changes
Other Study ID Numbers: SMRI/SPHS 2010-01
Study First Received: November 16, 2010
Results First Received: August 29, 2013
Last Updated: January 7, 2014

Keywords provided by Faith Dickerson, PhD, MPH, Sheppard Pratt Health System:
Probiotic supplements

Additional relevant MeSH terms:
Psychotic Disorders
Schizophrenia Spectrum and Other Psychotic Disorders
Mental Disorders processed this record on August 22, 2017