Is the serotonin transporter polymorphism (5-HTTLPR) a potential marker for suicidal behavior in bipolar disorder patients?
BACKGROUND
Suicide prediction is a huge challenge for mental health workers. Structured interviews based on epidemiological and clinical factors don't show effectiveness for suicide prevention. Biological markers, such as 5-HTTLPR, could help for identification of potential suicide attempters.


METHODS
We evaluated 198 bipolar patients and 103 health controls, using a structured interview according to DSM-IV criteria. Genotyping, blind of clinical assessment for identification of S carriers and structured interviews were performed in order to describe clinical and epidemiological factors which could be associated with suicide behavior. Statistical analyses were calculated by the x(2) test and logistic regression model.


RESULTS
We found that 26.77% and 16.67% had a lifetime history of non violent suicide attempt and violent suicide attempt, respectively. The clinical factors associated with violent and non violent suicide attempt had several differences. Violent suicide attempters had an earlier illness onset and had a higher number of psychiatric comorbidities (borderline personality disorder, panic disorder and alcoholism). The frequency of S allele carriers was higher only in those patients who had made a violent suicide attempt in their lifetime (x(2)=16.969; p=0.0001). In a logistic regression model including these factors, S allele carrier (5-HTTLPR) was the only factor associated with violent suicide attempt.


CONCLUSIONS
Sample size and retrospective assessment of suicide behavior history are the limitations of this study.


CONCLUSIONS
Our study showed that serotonin polymorphism (5-HTTLPR) is strongly associated with violent suicidal behavior in BD patients. If confirmed, our results could be an important step to create a genetic tool for long-term suicide prediction.
Neves
Fernando Silva
FS
Department of Mental Health, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil. fneves.bhz@terra.com.br
Malloy-Diniz
Leandro Fernandes
LF
Romano-Silva
Marco Aurélio
MA
Aguiar
Gabriel Costa
GC
de Matos
Lorena Oliveira
LO
Correa
Humberto
H
D000328:Adult; D017668:Age of Onset; D000437:Alcoholism / Q000175:diagnosis / Q000235:genetics / Q000523:psychology; D000483:Alleles; D001714:Bipolar Disorder / Q000175:diagnosis / Q000235:genetics* / Q000523:psychology; D001883:Borderline Personality Disorder / Q000175:diagnosis / Q000235:genetics / Q000523:psychology; D015897:Comorbidity; D005260:Female; D006580:Genetic Carrier Screening; D005819:Genetic Markers / Q000235:genetics*; D020022:Genetic Predisposition to Disease / Q000523:psychology; D005838:Genotype; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016584:Panic Disorder / Q000175:diagnosis / Q000235:genetics / Q000523:psychology; D011110:Polymorphism, Genetic / Q000235:genetics*; D012307:Risk Factors; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*; D013406:Suicide, Attempted / Q000523:psychology*; D014754:Violence / Q000523:psychology
D005819:Genetic Markers; C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins