title: Suicidal thoughts are associated with platelet counts in adolescent inpatients.
abstract: OBJECTIVE
  Platelets (PLT), which serve as the primary hemostatic indicator, can be used as a peripheral model for studying monoamine turnover in the brain. Therefore, they are attractive targets as circulatory biomarkers for the detection of psychiatric disorders. However, PLT counts have not been utilized as a peripheral biomarker of psychopathology.
  
  
  METHODS
  This study was a retrospective analysis of PLT counts upon admission of 108drug-naïve adolescents hospitalized in an inpatient psychiatric department. PLT counts of patients with suicidal ideation (SI) were compared with those of nonsuicidal in patients (NSI) and those of 77 healthy adolescents, serving as a control group. The patients' disorders were diagnosed and classified by one of four American Psychiatric Association, Diagnostic and Statistical Manual of Mental Disorders, 4th ed. (DSM IV) diagnoses, that is, unipolar depression, bipolar depression, schizophrenia, and a pooled group of conduct and borderline personality disorders.
  
  
  RESULTS
  Significantly higher PLT counts were observed in SI patients, as compared with NSI patients (300,200±53.3/mL vs. 253,900±53.2/mL, respectively; p=0.0001). A significant difference in PLT counts in SI patients, relative to the control group, was also noted (300,200±53.3/mL vs. 254,000±52/mL, respectively; p=<10(-26)). Finally, a significant difference in PLT counts was observed between conduct/borderline personality disorders patient with and without suicidal ideation (292,000±55/mL vs. 246,000±64/mL, respectively; p=0.001).
  
  
  CONCLUSIONS
  PLT counts are higher in suicidal hospitalized adolescents than in nonsuicidal inpatients, as well as than in controls.
authors: The Beer-Sheva Mental Health Center, Beer-Sheva, Israel. ragolsky@bgu.ac.il
authors: Micha
authors: M
authors: Ragolsky
authors: Hady
authors: H
authors: Shimon
authors: Hadar
authors: H
authors: Shalev
authors: Abraham
authors: A
authors: Weizman
authors: Eitan
authors: E
authors: Rubin
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000523:psychology*; D001792:Blood Platelets / Q000166:cytology* / Q000502:physiology; D016022:Case-Control Studies; D002648:Child; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006801:Humans; D007297:Inpatients / Q000523:psychology; D008297:Male; D001523:Mental Disorders / Q000097:blood* / Q000523:psychology*; D010976:Platelet Count; D012189:Retrospective Studies; D059020:Suicidal Ideation