Dataset Information

Positron Emission Tomography Studies of the Glial Cell Marker Translocator Protein in Patients With Psychosis: A Meta-analysis Using Individual Participant Data.

ABSTRACT:

Background

Accumulating evidence suggests that the immune system may be an important target for new treatment approaches in schizophrenia. Positron emission tomography and radioligands binding to the translocator protein (TSPO), which is expressed in glial cells in the brain including immune cells, represents a potential method for patient stratification and treatment monitoring. This study examined whether patients with first-episode psychosis and schizophrenia had altered TSPO levels compared with healthy control subjects.

Methods

PubMed was searched for studies comparing patients with psychosis with healthy control subjects using second-generation TSPO radioligands. The outcome measure was total distribution volume (V_T), an index of TSPO levels, in frontal cortex, temporal cortex, and hippocampus. Bayes factors (BFs) were applied to examine the relative support for higher, lower, or no difference in patients' TSPO levels compared with healthy control subjects.

Results

Five studies, with 75 participants with first-episode psychosis or schizophrenia and 77 healthy control subjects, were included. BFs showed strong support for lower V_T in patients relative to no difference (all BFs > 32), or relative to higher V_T (all BFs > 422), in all brain regions. From the posterior distributions, mean patient-control differences in standardized V_T values were -0.48 for frontal cortex (95% credible interval [CredInt] = -0.88 to 0.09), -0.47 for temporal cortex (CredInt = -0.87 to -0.07), and -0.63 for hippocampus (CredInt = -1.00 to -0.25).

Conclusions

The lower levels of TSPO observed in patients may correspond to altered function or lower density of brain immune cells. Future studies should focus on investigating the underlying biological mechanisms and their relevance for treatment.

SUBMITTER: Plaven-Sigray P

PROVIDER: S-EPMC7893597 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Publications

Positron Emission Tomography Studies of the Glial Cell Marker Translocator Protein in Patients With Psychosis: A Meta-analysis Using Individual Participant Data.

Plavén-Sigray Pontus P Matheson Granville J GJ Collste Karin K Ashok Abhishekh H AH Coughlin Jennifer M JM Howes Oliver D OD Mizrahi Romina R Pomper Martin G MG Rusjan Pablo P Veronese Mattia M Wang Yuchuan Y Cervenka Simon S

Biological psychiatry 20180306 6

<h4>Background</h4>Accumulating evidence suggests that the immune system may be an important target for new treatment approaches in schizophrenia. Positron emission tomography and radioligands binding to the translocator protein (TSPO), which is expressed in glial cells in the brain including immune cells, represents a potential method for patient stratification and treatment monitoring. This study examined whether patients with first-episode psychosis and schizophrenia had altered TSPO levels c ...[more]

PMID: 29653835

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Dataset Information

Positron Emission Tomography Studies of the Glial Cell Marker Translocator Protein in Patients With Psychosis: A Meta-analysis Using Individual Participant Data.

Background

Methods

Results

Conclusions

Publications

Positron Emission Tomography Studies of the Glial Cell Marker Translocator Protein in Patients With Psychosis: A Meta-analysis Using Individual Participant Data.

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