NCT01384604

Brief Summary

The overall goal of this project is to identify intermediate phenotypes for psychosis across the schizophrenia and bipolar disorders boundary with implications for future genetic studies. Recent studies provide considerable evidence that schizophrenia and psychotic bipolar disorder may share overlapping etiologic determinants. Identifying disease-related genetic effects is a major focus in schizophrenia and bipolar research, with enormous implications for diagnosis and treatment for these two disorders. Efforts have been multifaceted, with the ultimate goal of describing causal paths from specific genetic variants, to changes in neuronal functioning, to altered brain anatomy, to behavioral and functional impairments. Parallel efforts have identified and refined several alternative endophenotypes that are stable, heritable, have (partly) known biological substrates, and are associated with psychosis liability. Although many such endophenotypes have been individually studied in schizophrenia, and to a lesser extent in bipolar disorder, no study has comprehensively assessed a broad panel of these markers in the two disorders with parallel recruitment, and the extent to which they mark independent aspects of psychosis risk, or their overlap in the two disorders. In this research project, we will examine a broad panel of putative endophenotypes in affected individuals and their first degree, biological relatives in order to: 1) characterize the degree of familial phenotypic overlap between schizophrenia and psychotic bipolar disorders; 2) identify patterns of endophenotypes unique to the two disorders; and, 3) contrast the heritability of endophenotypes across the disorders. We will obtain measures of neurophysiology (e.g., eye tracking, P50 gating, PPI, and P300), neurocognition (e.g., attention/vigilance, episodic and working memory), and brain structure (e.g., volumes of gray and white matter in specified brain regions). Blood samples will also be collected and stored for formal DNA linkage analyses using the independent phenotypes identified above. All volunteers will also be given the option to donate dermal biopsies for future research studies. Establishing similarities and differences in the endophenotypic signatures within schizophrenia and bipolar families will provide important insights for future genetic studies, and clarify concepts about common and distinct aspects of pathophysiology, potentially meaningful heterogeneity with disorders, and the clinical boundaries of the two most common psychotic disorders in adult psychiatry. This line of investigation will potentially impact our conceptualization of psychotic disorders, help us make critical strides to identify the pathophysiology of psychosis, and guide development of new specific treatments targeting particular deficits.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
1,189

participants targeted

Target at P75+ for all trials

Timeline
Completed

Started Dec 2007

Longer than P75 for all trials

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

December 1, 2007

Completed
3.6 years until next milestone

First Submitted

Initial submission to the registry

June 27, 2011

Completed
2 days until next milestone

First Posted

Study publicly available on registry

June 29, 2011

Completed
1.8 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

May 1, 2013

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

May 1, 2013

Completed
Last Updated

January 16, 2019

Status Verified

January 1, 2019

Enrollment Period

5.4 years

First QC Date

June 27, 2011

Last Update Submit

January 15, 2019

Conditions

Keywords

SchizophreniaSchizoaffective disorderBipolar disorderPsychosisGeneticsPhenotype

Eligibility Criteria

Age15 Years - 70 Years
Sexall
Healthy VolunteersYes
Age GroupsChild (0-17), Adult (18-64), Older Adult (65+)
Sampling MethodNon-Probability Sample
Study Population

Individuals with schizophrenia, schizoaffective, or bipolar I disorder.

You may qualify if:

  • DSM-IV diagnosis of schizophrenia, schizoaffective disorder, or bipolar disorder with psychotic features
  • Ages 15-70 years old
  • Must have a first degree, biological relative in the same age range who is willing and available to participate

You may not qualify if:

  • Diagnosis of an organic brain disease
  • Meets criteria for alcohol or substance abuse with the last month; alcohol or substance dependence within the last 3 months; or, has an extensive history of drug dependence
  • History of seizures, serious head injury, concussions, or other evidence of brain disease
  • Medical illnesses that are not currently well-controlled

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

University of Texas Southwestern Medical Center

Dallas, Texas, 75390, United States

Location

Related Links

Biospecimen

Retention: SAMPLES WITH DNA

Blood, no more than 30cc; urine, small collection cup (about 30cc) to administer drug urine screen and pregnancy tests for females; buccal swabs (at least 5 swabs from volunteers that cannot donate blood); and, optional: 4mm punch of skin for dermal biopsy.

MeSH Terms

Conditions

SchizophreniaPsychotic DisordersBipolar Disorder

Condition Hierarchy (Ancestors)

Schizophrenia Spectrum and Other Psychotic DisordersMental DisordersBipolar and Related DisordersMood Disorders

Study Design

Study Type
observational
Observational Model
FAMILY BASED
Time Perspective
CROSS SECTIONAL
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Principal Investigator

Study Record Dates

First Submitted

June 27, 2011

First Posted

June 29, 2011

Study Start

December 1, 2007

Primary Completion

May 1, 2013

Study Completion

May 1, 2013

Last Updated

January 16, 2019

Record last verified: 2019-01

Locations