Brain imaging using fMRI and its impact on the monitoring of pharmacotherapy in schizophrenia – latest report

iStock_000011113599XSmallThe scientists from New York discovered that functional nuclear MRI scan allows to monitor patient’s response to antipsychotic drugs used schizophrenia. The results were published in The American Journal of Psychiatry.

Schizophrenia is a severe and debilitating mental illness that affects approximately 1% of the population. Its etiology is multifactorial with a strong participation of genetic and environmental factors. The disease appears as subtle structural and functional disorders within various brain structures such as the striatum, hippocampus and prefrontal cortex. At the molecular level, dopamine is traditionally associated with schizophrenia, as evidenced by the fact that dopamine D2 receptor antagonists attenuate the symptoms, and the drugs that release dopamine exacerbate the positive symptoms of schizophrenia. Abnormalities are closely associated with the deficits of glutamate and GABA, which is hypothesized to play a role in the pathophysiology of schizophrenia.

The study conducted by American scientists included 24 patients with the first episode of psychosis and 24 healthy people. All of the patients were 15-40 years old.

The patients underwent imaging using functional nuclear MRI scan, both at the baseline and after 12 weeks of being treated with antipsychotics. Symptoms were monitored using the psychiatric scale – The Brief Psychiatric Rating Scale. Second group (healthy people) underwent brain imaging twice.

The researchers checked their functional connectivity in the striatal regions. Changes were compared with the parallelly appearing reduction of psychotic symptoms.

It was observed that every time psychosis intensified, functional connectivity between areas of the striatum and the anterior cingulate, dorsolateral prefrontal cortex and limbic regions of the hippocampus increased. An inverse relationship was observed between the reduction of psychosis and functional communication structures of striatal regions in the parietal lobe.

The researchers point out that the increased functional connectivity of the prefrontal areas with the striatum can serve as a biomarker indicating improvement in symptoms associated with antipsychotic treatment.

Dr. Deepak Sarpal points out that this study reports the predictive value of fMRI (functional nuclear MRI scan) approved in the independent study group of patients taking antipsychotics. What is more, he adds that the results of this study allow fMRI images to be an important tool in the treatment of psychiatric disorders.


Written by: Agata Zwierz, Katarzyna Gałaszkiewicz, Klaudia Zyzak

Source:
1. Deepak K. Sarpal, Miklos Argyelan, Delbert G. Robinson, Philip R. Szeszko, Katherine H. Karlsgodt, Majnu John, Noah Weissman, Juan A. Gallego, John M. Kane, Todd Lencz, Anil K. Malhotra. Baseline Striatal Functional Connectivity as a Predictor of Response to Antipsychotic Drug Treatment. American Journal of Psychiatry, 2015; appi.ajp.2015.1
2. van Os J, Rutten BP, Poulton R. Gene-environment interactions in schizophrenia: Review of epidemiological findings and future directions. Schizophr Bull 2008; 34 :1066–1082
3. Harrison PJ, Weinberger DR. Schizophrenia genes, gene expression, and neuropathology: On the matter of their convergence. Mol Psychiatry 2005; 10 :40–68;
4. Lisman JE, Coyle JT, Green RW, Javitt DC, Benes FM, Heckers S, Grace AA. Circuit-based framework for understanding neurotransmitter and risk gene interactions in schizophrenia. Trends Neurosci 2008; 31 :234–242
5. Howes OD, Kapur S. The dopamine hypothesis of schizophrenia: Version III–the final common pathway. Schizophr Bull 2009; 35 :549–562.
6. Davis KL, Kahn RS, Ko G, Davidson M. Dopamine in schizophrenia: A review and reconceptualization. Am J Psychiatry 1991; 148 :1474–1486
7. Laruelle M, Kegeles LS, Abi-Dargham A. Glutamate, dopamine, and schizophrenia: From pathophysiology to treatment. Ann N Y Acad Sci 2003; 1003 :138–158


Would You like to know more? Watch on MEDtube.net: Hippocampal Malrotation – Head MRI

No Comments.

Leave a Reply

(required)

(required)

Time limit is exhausted. Please reload the CAPTCHA.