Karen Amaral Tavares Pinheiro - Universidade Católica de Pelotas

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prefrontal cortices of suicide victims compared with both psychiatric patients who have not
attempted suicide and control subjects 18,19 .
Despite the high lifetime rate of suicide, most people with depression never attempt
suicide. This fact raises the question as to why some people with depression are at risk for
attempting suicide and others are not 10 . Considering that various clinical and epidemiological
studies have identified stressors as an important risk factor for suicide, we additionally
investigated whether SLEs during pregnancy influence BDNF levels. By regression analysis,
three or more SLEs correlated with smaller differences in BDNF levels than did suicide risk
(three- and eight-fold changes in risk, respectively).
However, we do not discount the clinical relevance of SLEs as a factor that influences
suicidal behavior. Indeed, alterations in the stress system (particularly hyperactivation of the
HPA axis) are well documented in suicide victims and in depressed suicide attempters who
subsequently complete suicide. However, time between the suicide attempt and the
examination could account for the differences reported in some studies 20,21,22,23 .
Furthermore, several arguments suggest that suicidal behavior is a disorder of its own,
although psychiatric disturbances (such as depression) are major contributing factors. The
presence of psychopathology is a strong predictor of suicide; however, there is a certain
predisposition to suicide that is independent of the main psychiatric disorders 5 . Considering
the variety of psychological events and biological changes that occur during the course of a
pregnancy, it is reasonable to believe that factors beyond SLEs and PPADs may be affecting
BDNF levels and suicide risk. Thus, further investigation is required to determine whether the
observed differences in serum BDNF levels are specifically related to either mental disorders
or suicide risk during the perinatal period. Several studies have proposed that impaired
structural and functional plasticity are involved in the molecular and cellular events that lead
to psychiatric disorders, such as mood disorders and suicidal behavior. Support for this theory