Dissertation committee:
Επίκουρος καθηγητής Χρήστος Χριστοδούλου, Επίκουρος καθηγητής Ρωσσέτος Γουρνέλλης, Καθηγητής Ψυχιατρικής Χαράλαμπος Παπαγεωργίου
Summary:
BACKGROUND: The role of lipids and the function of HPA axis constitute a modern
research field in the neurobiology of suicidal behavior. The present study
focuses on total cholesterol levels and basic morning cortisol and as well as
on the evaluation of the HPA axis through the estimation of dexamethasone
suppression test (DST) in patients with recent suicide attempts. Moreover, the
relationship with psychometric parameters was explored.
METHOD: One hundred fifty seven patients with recent suicide attempts (48men
and 109 women) in the age range of 18 to 91 were studied. Total cholesterol
levels and basic morning cortizol were measured in these patients. DST was used
in 87 of these patients. Psychiatric diagnoses were established according to
DSM-IV-TR. All participants were evaluated using the Suicide Intent Scale
(SIS), the Beck Depression Inventory (BDI), the Agression Questionnaire (AQ)
and the Symptom Checklist-90-R (SCL-90-R). A control group of 160 healthy
individuals (60 men and 100 women) matched by sex and age to the suicide
attempters was used for the comparison of total cholesterol and cortisol levels.
RESULTS: The group of suicide attempters had significantly lower total
cholesterol levels compared to the group of control subjects. Both men and
women had lower total cholesterol levels compared to same sex healthy controls.
The difference was present in all three diagnostic groups (psychosis, affective
disorder, and other diagnosis).
Female, but not male attempters had significantly higher BMI values compared to
healthy controls. Violent attempts were more frequent in male and in psychotic
attempters. There were no differences in total cholesterol levels betw
een violent and non-violent attempters. Basic cortisol levels did not differ
significantly between suicide attempters and healthy controls. No differences
were found in DST results between the two sexes, the three diagnostic groups
and violent-non violent suicide attempts. Total cholesterol and basic morning
cortisol levels did not differ significantly between suppressors and
non-suppressors. The correlations between total cholesterol, basic morning
cortisol, DST results and suicide intent, severity of depression or aggression
were all non-significant.
Violent attempters present a greater range and severity of psychopathology,
and significantly higher levels of perceived distress, more severe depressive
symptoms, and higher levels of obsessivity- compulsivity, anxiety and
psychoticism compared with non-violent attempters. There were, though, no
significant differences in the aggression rating scale score between violent
and non-violent attempters.
CONCLUSIONS: The results support the role of total cholesterol as a risk factor
for suicide attempts at least in psychiatric patients. The hypothesis of HPA
hyperactivity in suicidal behavior is not been confirmed by this study. Violent
methods are associated with severe psychic dysphoria and severe depressive
symptoms in combination with high levels of anxiety, obsessivity- compulsivity
and psychoticism. Total cholesterol levels were not related to any specific
psychiatric symptomatology and the neurobiological mechanisms that connect low
cholesterol levels to auto-destructive behaviors remain unclear.
Keywords:
Dexamethasone suppression test, Total cholesterol, Suicide attempt, Aggression, Suicide intent
