title: Transthyretin in cerebrospinal fluid from suicide attempters.
abstract: BACKGROUND
  Earlier studies have found that transthyretin (TTR) is reduced in cerebrospinal fluid (CSF) from patients with major depressive disorder and that levels correlate negatively with suicidal ideation. The purpose of this study was to examine CSF-TTR in a cohort of suicide attempters with different psychiatric diagnoses and to further assess the relationship between CSF-TTR and suicidal behaviour as well as psychiatric symptoms.
  
  
  METHODS
  TTR was measured using enzyme-enhanced Mancini. Diagnostics were performed with the Diagnostic and Statistical Manual of Mental Disorders. Psychiatric symptoms and suicidal behaviour were rated using the Comprehensive Psychopathological Rating Scale (CPRS), the Suicide Assessment Scale and the Suicidal Intent Scale.
  
  
  RESULTS
  We found no significant difference in CSF-TTR levels between groups of different psychiatric diagnoses and controls. CSF-TTR correlated negatively to the CPRS item 17, "failing memory". No significant correlations between CSF-TTR and suicidal behaviour or suicide intent were found.
  
  
  CONCLUSIONS
  Correlation analysis is an indirect method of investigation and does not demonstrate causal relationships.
  
  
  CONCLUSIONS
  We conclude that CSF-TTR is unlikely to be relevant for suicidal behaviour and that further studies in non-suicidal psychiatric patients are needed before a role of CSF-TTR in depression can be established.
authors.affiliation: Division of Psychiatry, Department of Clinical Sciences, Kioskgatan 19, Lund University Hospital, 221 85 Lund, Sweden. Kristofer.Schultz@med.lu.se
authors.forename: Kristofer
authors.initials: K
authors.lastname: Schultz
authors.forename: Lil
authors.initials: L
authors.lastname: Träskman-Bendz
authors.forename: Asa
authors.initials: A
authors.lastname: Petersén
mesh_terms: D003865:Major Depressive Disorder / Q000134:cerebrospinal fluid / Q000453:epidemiology / Q000523:psychology; D039721:Diagnostic and Statistical Manual of Mental Disorders; D019263:Dysthymic Disorder / Q000134:cerebrospinal fluid / Q000453:epidemiology / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011228:Prealbumin / Q000134:cerebrospinal fluid*; D013406:Suicide, Attempted / Q000523:psychology* / Q000706:statistics & numerical data*
chemical_list: D011228:Prealbumin