title: Additive effects of elevated C-reactive protein and exposure to Herpes Simplex Virus type 1 on cognitive impairment in individuals with schizophrenia.
abstract: OBJECTIVE
  We investigated the effect of elevated levels of C-reactive protein (CRP) and exposure to Herpes simplex virus type 1 (HSV-1) on the severity of cognitive impairment in individuals with schizophrenia.
  
  
  METHODS
  We measured the levels of CRP and of antibodies to HSV-1 in serum samples from 588 individuals with schizophrenia by enzyme immunoassay tests. Cognitive functioning was measured with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and psychiatric symptoms with the Positive and Negative Syndrome Scale (PANSS). The effects of HSV1 and CRP on cognitive functioning were analyzed with linear and logistic regression analyses adjusting for demographic and clinical variables.
  
  
  RESULTS
  The individuals with elevated CRP levels and HSV-1 seropositivity had lower RBANS cognitive scores. The strongest effect was found in individuals who had both serological evidence of HSV-1 exposure and elevated levels of CRP. These individuals had odds of 2.35 to have an RBANS Total score<=60 as compared to individuals who were HSV-1 seronegative and who did not have elevated levels of CRP (p=.002). The risks of decreased cognitive functioning associated with HSV-1 exposure and elevated levels of CRP were independent and additive. There was no effect of HSV-1 exposure and CRP levels on the severity of symptoms as measured by the PANSS (all p>.5).
  
  
  CONCLUSIONS
  Elevated levels of CRP and exposure to HSV-1 are associated with the severity of cognitive impairment in schizophrenia. These findings indicate that infection and inflammation may play a major role in the cognitive deficits associated with schizophrenia.
authors: Stanley Research Program at Sheppard Pratt, Sheppard Pratt Health System, 6501 North Charles, St., Baltimore, MD 21204, USA. fdickerson@sheppardpratt.org
authors: Faith
authors: F
authors: Dickerson
authors: Cassie
authors: C
authors: Stallings
authors: Andrea
authors: A
authors: Origoni
authors: Crystal
authors: C
authors: Vaughan
authors: Sunil
authors: S
authors: Khushalani
authors: Robert
authors: R
authors: Yolken
mesh_terms: D000328:Adult; D000914:Antibodies, Viral / Q000097:blood*; D002097:C-Reactive Protein / Q000378:metabolism*; D003072:Cognition Disorders / Q000097:blood / Q000150:complications / Q000821:virology; D005260:Female; D006561:Herpes Simplex / Q000276:immunology*; D018259:Herpesvirus 1, Human / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D012559:Schizophrenia / Q000097:blood / Q000150:complications / Q000821:virology
chemical_list: D000914:Antibodies, Viral; D002097:C-Reactive Protein