Normal prepulse inhibition and habituation of acoustic startle response in suicidal depressive patients without psychotic symptoms.
BACKGROUND
Until now, there is a lack of useful biological markers to predict suicidal behavior in depressive patients. However, it is consistently found that suicidality is associated with a central serotonin deficit. Animal data suggest that prepulse inhibition (PPI) as well as habituation of the acoustic startle response (ASR), which are established as operational measures for sensorimotor gating, decreases after serotonin depletion. Thus, we investigated PPI and habituation of ASR in suicidal patients with depressive disorders as potential biological markers for suicidal behavior.


METHODS
PPI and habituation of ASR was measured in 20 depressive patients who had at least one suicide attempt within the last three month. Eighteen healthy matched controls were examined likewise.


RESULTS
Suicidal depressive patients did not differ from healthy controls in PPI, startle reactivity and habituation of ASR. Subgroup analyses showed that factors such as severity of depression, impulsiveness, gender, smoking, lethality of the last suicide attempt, number of suicide attempts, and medication had no influence on the results.


CONCLUSIONS
These results suggest that neither PPI nor habituation of ASR could serve as useful markers for suicidality.
Quednow
Boris B
BB
Department of Psychiatry, University of Bonn, Germany. quednow@bli.unizh.ch
Westheide
Jens
J
Kühn
Kai-Uwe
KU
Werner
Petra
P
Maier
Wolfgang
W
Hawellek
Barbara
B
Wagner
Michael
M
D000161:Acoustic Stimulation; D000293:Adolescent; D000328:Adult; D015415:Biomarkers; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology*; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006185:Habituation, Psychophysiologic; D006801:Humans; D008297:Male; D008875:Middle Aged; D011618:Psychotic Disorders / Q000453:epidemiology*; D011931:Reactive Inhibition; D013216:Reflex, Startle; D013406:Suicide, Attempted / Q000523:psychology* / Q000706:statistics & numerical data*
D015415:Biomarkers