title: Neutrophil-to-lymphocyte ratio predicting suicide risk in euthymic patients with bipolar disorder: Moderatory effect of family history.
abstract: BACKGROUND
  Neutrophil-to-lymphocyte ratio (NLR) has been independently related to bipolar disorder (BD) and factors associated with suicidal risk. The aim of our study was to explore the relationship between NLR and suicide risk in euthymic BD patients. We also sought to propose a model of interaction between NLR and stress-diathesis factors, leading to suicidal risk in BD.
  
  
  METHODS
  The study group consisted of 83 patients diagnosed with BD (36 suicide attempters; 47 suicide non-attempters), compared to the healthy control group (n=73) and matched according to age, gender, and body mass index (BMI). NLR was measured according to the complete blood count. Mood symptoms have been assessed by Young Mania Rating Scale and Montgomery-Asberg Depression Rating Scale. Early trauma and acute stress were evaluated by Early Trauma Inventory Self Report-Short Form and List of Threatening Experiences Questionnaire, respectively. Suicide risk has been assessed by Suicide Behaviors Questionnaire-Revised (SBQ-R).
  
  
  RESULTS
  Significant correlation was found between NLR and SBQ-R score. The main effects of suicide attempts on NLR, after covarying for confounders, were observed, indicating increased NLR in BD suicide attempters compared to healthy controls. We found significant moderatory effects of family history on NLR relationship to suicidal risk, with NLR being significant positive predictor of suicidal risk only in the patients with positive family history of suicide attempts.
  
  
  CONCLUSIONS
  The results suggest an enhancing effect of positive family history of suicide attempts on predictive effect of NLR on suicide risk. Our data support the idea that immune markers can predict suicide attempt risk in BD, but only in the subpopulation of BD patients with family history of suicide attempts. This could lead to prevention in suicide behavior in the patient population at particular risk of suicide.
authors.affiliation: Clinic of Psychiatry, Clinical Centre of Serbia, Pasterova 2, 11000 Belgrade, Serbia; School of Medicine, University of Belgrade, Dr Subotica 8, 11000 Belgrade, Serbia.
authors.forename: Maja
authors.initials: M
authors.lastname: Ivković
authors.affiliation: Clinic of Psychiatry, Clinical Centre of Serbia, Pasterova 2, 11000 Belgrade, Serbia. Electronic address: majapantovic@yahoo.it.
authors.forename: Maja
authors.initials: M
authors.lastname: Pantović-Stefanović
authors.affiliation: Clinic of Psychiatry, Clinical Centre of Serbia, Pasterova 2, 11000 Belgrade, Serbia.
authors.forename: Bojana
authors.initials: B
authors.lastname: Dunjić-Kostić
authors.affiliation: School of Medicine, University of Kragujevac, Svetozara Markovica 69, 11000 Kragujevac, Serbia.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Jurišić
authors.affiliation: Clinic of Psychiatry, Clinical Centre of Serbia, Pasterova 2, 11000 Belgrade, Serbia; School of Medicine, University of Belgrade, Dr Subotica 8, 11000 Belgrade, Serbia.
authors.forename: Maja
authors.initials: M
authors.lastname: Lačković
authors.affiliation: Clinic of Psychiatry, Clinical Centre of Serbia, Pasterova 2, 11000 Belgrade, Serbia; School of Medicine, University of Belgrade, Dr Subotica 8, 11000 Belgrade, Serbia.
authors.forename: Sanja
authors.initials: S
authors.lastname: Totić-Poznanović
authors.affiliation: Clinic of Psychiatry, Clinical Centre of Serbia, Pasterova 2, 11000 Belgrade, Serbia; School of Medicine, University of Belgrade, Dr Subotica 8, 11000 Belgrade, Serbia.
authors.forename: Aleksandar A
authors.initials: AA
authors.lastname: Jovanović
authors.affiliation: Clinic of Psychiatry, Clinical Centre of Serbia, Pasterova 2, 11000 Belgrade, Serbia; School of Medicine, University of Belgrade, Dr Subotica 8, 11000 Belgrade, Serbia.
authors.forename: Aleksandar
authors.initials: A
authors.lastname: Damjanović
mesh_terms: D000328:Adult; D001714:Bipolar Disorder / Q000097:blood* / Q000523:psychology*; D005190:Family; D005260:Female; D006801:Humans; D007958:Leukocyte Count; D018655:Lymphocyte Count; D008214:Lymphocytes; D008297:Male; D008875:Middle Aged; D019964:Mood Disorders / Q000523:psychology; D009504:Neutrophils; D011237:Predictive Value of Tests; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors; D057566:Self Report; D055771:Serbia / Q000453:epidemiology; D012959:Socioeconomic Factors; D013405:Suicide / Q000523:psychology* / Q000706:statistics & numerical data*; D013406:Suicide, Attempted / Q000523:psychology / Q000706:statistics & numerical data; D011795:Surveys and Questionnaires