VIRUS ASSOCIATION TO COGNITIVE FUNCTION IN SCHIZOPHRENIA

Schizophr Res. 2008 Dec;106(2-3):268-74. Epub 2008 Sep 17.
Antibodies to cytomegalovirus and Herpes Simplex Virus 1 associated with cognitive function in schizophrenia.

Shirts BH, Prasad KM, Pogue-Geile MF, Dickerson F, Yolken RH, Nimgaonkar VL.
Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States.

BACKGROUND: Cognitive impairment in the form of decreased working memory and executive functions has been recognized as a key deficit in schizophrenia. Neurotropic viruses have been associated with focal gray matter deficits in patients with schizophrenia. We evaluated whether such agents alter cognitive function in schizophrenia.

METHODS: The sample consisted of 329 patients diagnosed with schizophrenia or schizoaffective disorder. We evaluated associations between exposure to selected agents (Herpes Simplex Viruses 1 and 2 (HSV1, HSV2 respectively) cytomegalovirus (CMV) and Toxoplasma gondii) and scores on the Trail Making Test (TMT), controlling for relevant variables.

RESULTS: Serological evidence of exposure to CMV was associated with impaired performance on TMT part A time to completion (p=0.044), a measure of visual search, working memory, and psychomotor speed. Both CMV and HSV1 were significantly associated with increased errors on TMT part B

PSYCHOSIS CAUSED BY MICROBIAL AGENTS?

Mol Psychiatry. 2008 May;13(5):470-9. Epub 2008 Feb 12.

Are some cases of psychosis caused by microbial agents? A review of the evidence.

Yolken RH, Torrey EF.

The Stanley Laboratory of Developmental Neurovirology, Department of Pediatrics, Johns Hopkins University Medical Center, Baltimore, MD 21287-4933, USA. yolken@mail.jhmi.edu

The infectious theory of psychosis, prominent early in the twentieth century, has recently received renewed scientific support. Evidence has accumulated that schizophrenia and bipolar disorder are complex diseases in which many predisposing genes interact with one or more environmental agents to cause symptoms. The protozoan Toxoplasma gondii and cytomegalovirus are discussed as examples of infectious agents that have been linked to schizophrenia and in which genes and infectious agents interact. Such infections may occur early in life and are thus consistent with neurodevelopmental as well as genetic theories of psychosis. The outstanding questions regarding infectious theories concern timing and causality. Attempts are underway to address the former by examining sera of individuals prior to the onset of illness and to address the latter by using antiinfective medications to treat individuals with psychosis. The identification of infectious agents associated with the etiopathogenesis of schizophrenia might lead to new methods for the diagnosis, treatment and prevention of this disorder.

PMID: 18268502 [PubMed - indexed for MEDLINE]