title: Exploratory investigation of biomarker candidates for suicide in schizophrenia and bipolar disorder.
abstract: BACKGROUND
  Clozapine and lithium increase neurosteroids in rodents, and both drugs demonstrate antisuicidal actions. We therefore hypothesized that neurosteroid levels may be reduced in patients with schizophrenia or bipolar disorder who completed suicide.
  
  
  OBJECTIVE
  To investigate neurosteroid levels in the parietal cortex and posterior cingulate in schizophrenia and bipolar patients who died by suicide, and compare them with patients with these disorders who died of other causes.
  
  
  METHODS
  Neurosteroid levels were quantified by gas chromatography/mass spectrometry in the parietal cortex and posterior cingulate. Mann-Whitney analyses were conducted in exploratory post hoc analyses to investigate neurosteroids as possible biomarker candidates for suicide.
  
  
  RESULTS
  The study showed that pregnenolone was significantly decreased in the parietal cortex in the combined group of patients with schizophrenia or bipolar disorder who died by suicide (n = 13) compared with patients with these disorders who died of other causes (n = 17, p = .02). Pregnenolone levels were also lower in the parietal cortex in the individual group of schizophrenia patients who died by suicide (n = 4) compared with schizophrenia patients who died of other causes (n = 11) p = .04).
  
  
  CONCLUSIONS
  Pregnenolone alterations may be relevant to the neurobiology of suicide in schizophrenia and bipolar disorder.
authors.affiliation: <location>Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA</location> <location>Veterans Affairs Mid-Atlantic Mental Illness Research, Education, and Clinical Center (MIRECC) and Durham VA Medical Center, Durham, NC, USA</location>
authors.forename: Nagy A
authors.initials: NA
authors.lastname: Youssef
authors.affiliation: <location>Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA</location> <location>Veterans Affairs Mid-Atlantic Mental Illness Research, Education, and Clinical Center (MIRECC) and Durham VA Medical Center, Durham, NC, USA</location>
authors.forename: Daniel W
authors.initials: DW
authors.lastname: Bradford
authors.affiliation: <location>Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA</location> <location>Veterans Affairs Mid-Atlantic Mental Illness Research, Education, and Clinical Center (MIRECC) and Durham VA Medical Center, Durham, NC, USA</location>
authors.forename: Jason D
authors.initials: JD
authors.lastname: Kilts
authors.affiliation: <location>Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA</location> <location>Veterans Affairs Mid-Atlantic Mental Illness Research, Education, and Clinical Center (MIRECC) and Durham VA Medical Center, Durham, NC, USA</location>
authors.forename: Steven T
authors.initials: ST
authors.lastname: Szabo
authors.affiliation: <location>Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA</location> <location>Veterans Affairs Mid-Atlantic Mental Illness Research, Education, and Clinical Center (MIRECC) and Durham VA Medical Center, Durham, NC, USA</location>
authors.forename: Jennifer C
authors.initials: JC
authors.lastname: Naylor
authors.affiliation: <location>Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA</location> <location>Veterans Affairs Mid-Atlantic Mental Illness Research, Education, and Clinical Center (MIRECC) and Durham VA Medical Center, Durham, NC, USA</location>
authors.forename: Trina B
authors.initials: TB
authors.lastname: Allen
authors.affiliation: <location>Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA</location> <location>Veterans Affairs Mid-Atlantic Mental Illness Research, Education, and Clinical Center (MIRECC) and Durham VA Medical Center, Durham, NC, USA</location> <location>Center for Health Services Research in Primary Care, Durham, NC, USA</location>
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Strauss
authors.affiliation: <location>Department of Psychiatry, University of North Carolina at Chapel Hill, NC, USA</location>
authors.forename: Robert M
authors.initials: RM
authors.lastname: Hamer
authors.forename: Mira
authors.initials: M
authors.lastname: Brancu
authors.affiliation: <location>Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA</location> <location>Veterans Affairs Mid-Atlantic Mental Illness Research, Education, and Clinical Center (MIRECC) and Durham VA Medical Center, Durham, NC, USA</location>
authors.forename: Mira
authors.initials: M
authors.lastname: Brunca
authors.affiliation: <location>Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA</location> <location>Veterans Affairs Mid-Atlantic Mental Illness Research, Education, and Clinical Center (MIRECC) and Durham VA Medical Center, Durham, NC, USA</location>
authors.forename: Lawrence J
authors.initials: LJ
authors.lastname: Shampine
authors.affiliation: <location>Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA</location> <location>Veterans Affairs Mid-Atlantic Mental Illness Research, Education, and Clinical Center (MIRECC) and Durham VA Medical Center, Durham, NC, USA</location>
authors.forename: Christine E
authors.initials: CE
authors.lastname: Marx
mesh_terms: D000328:Adult; D000368:Aged; D001344:Autopsy; D015415:Biomarkers / Q000378:metabolism; D001714:Bipolar Disorder / Q000378:metabolism*; D001921:Brain / Q000378:metabolism*; D016022:Case-Control Studies; D002851:Chromatography, High Pressure Liquid; D003687:Dehydroepiandrosterone / Q000378:metabolism*; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006179:Gyrus Cinguli / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D010296:Parietal Lobe / Q000378:metabolism; D010865:Pilot Projects; D011280:Pregnanolone / Q000378:metabolism*; D011284:Pregnenolone / Q000378:metabolism*; D012559:Schizophrenia / Q000378:metabolism*; D013405:Suicide; D055815:Young Adult
chemical_list: D015415:Biomarkers; D003687:Dehydroepiandrosterone; D011284:Pregnenolone; D011280:Pregnanolone
keywords: bipolar disorder; neurosteroid; parietal cortex; pregnenolone; schizophrenia; suicide