title: Abnormalities in chemokine levels in schizophrenia and their clinical correlates.
abstract: Chemokines are promising biomarkers of immune activation and inflammation, but evidence for chemokine abnormalities in schizophrenia and their relationship to clinical factors remains inconclusive. We aimed to understand chemokine-related diagnostic differences and clinical correlates using a comprehensive panel and studying a large, well-characterized sample of adults with and without schizophrenia. We studied 134 outpatients with schizophrenia or schizoaffective disorder and 112 healthy comparison (HC) individuals, 26 to 65years of age. Clinical measures were obtained, and plasma levels of 11 chemokines were assessed using multiplex immunoassay. Schizophrenia vs. HC differences were tested for each chemokine, adjusting for age, gender, body mass index, and current smoking status. We also examined whether age and gender relationships differed between diagnostic groups. Using logistic regression, we created a Chemokine Index (CI) and explored its clinical correlates. Levels of monocyte chemoattractant protein-1 (MCP-1/CCL2), macrophage inflammatory protein-1β (MIP-1β/CCL4), Eotaxin-1 (CCL11), thymus and activation-regulated chemokine (TARC/CCL17), and macrophage-derived chemokine (MDC/CCL22) were significantly higher in persons with schizophrenia than HCs. Group differences in TARC were reduced after adjusting for covariates. The CI, a linear combination of Eotaxin-1 and MDC levels, was positively associated with age, duration of schizophrenia, and severity of negative symptoms. Levels of chemokines with neuroimmune regulatory effects were higher in individuals with schizophrenia, particularly in older and chronic patients. Treatments aimed at normalizing chemokine levels might improve mental and physical health among schizophrenia patients as they age.
authors.affiliation: Department of Psychiatry, University of California, San Diego, USA; Department of Family Medicine and Public Health, University of California, San Diego, USA.
authors.forename: Suzi
authors.initials: S
authors.lastname: Hong
authors.affiliation: Department of Psychiatry, University of California, San Diego, USA.
authors.forename: Ellen E
authors.initials: EE
authors.lastname: Lee
authors.affiliation: Department of Psychiatry, University of California, San Diego, USA; Sam and Rose Stein Institute for Research on Aging, University of California, San Diego, USA.
authors.forename: Averria Sirkin
authors.initials: AS
authors.lastname: Martin
authors.affiliation: Department of Psychiatry, University of California, San Diego, USA.
authors.forename: Benchawanna
authors.initials: B
authors.lastname: Soontornniyomkij
authors.affiliation: Department of Psychiatry, University of California, San Diego, USA.
authors.forename: Virawudh
authors.initials: V
authors.lastname: Soontornniyomkij
authors.affiliation: Department of Psychiatry, University of California, San Diego, USA.
authors.forename: Cristian L
authors.initials: CL
authors.lastname: Achim
authors.affiliation: Department of Psychiatry, University of California, San Diego, USA; Sam and Rose Stein Institute for Research on Aging, University of California, San Diego, USA.
authors.forename: Chase
authors.initials: C
authors.lastname: Reuter
authors.affiliation: Cousins Center for Psychoneuroimmunology, Semel Institute for Neuroscience, University of California, Los Angeles, USA.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Irwin
authors.affiliation: Department of Psychiatry, University of California, San Diego, USA; Desert-Pacific Mental Illness Research Education and Clinical Center, Veterans Affairs San Diego Healthcare System, San Diego, USA.
authors.forename: Lisa T
authors.initials: LT
authors.lastname: Eyler
authors.affiliation: Department of Psychiatry, University of California, San Diego, USA; Sam and Rose Stein Institute for Research on Aging, University of California, San Diego, USA; Department of Neurosciences, University of California, San Diego, USA. Electronic address: djeste@ucsd.edu.
authors.forename: Dilip V
authors.initials: DV
authors.lastname: Jeste
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000097:blood / Q000276:immunology; D015415:Biomarkers / Q000097:blood; D018925:Chemokines / Q000097:blood*; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007118:Immunoassay; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011618:Psychotic Disorders / Q000097:blood* / Q000276:immunology*; D012559:Schizophrenia / Q000097:blood* / Q000276:immunology*; D012727:Sex Characteristics
chemical_list: D015415:Biomarkers; D018925:Chemokines
keywords: Aging; Chemokines; Immune system; Inflammation; Schizophrenia