Low CSF 5-HIAA level in high-lethality suicide attempters: fact or artifact?

Total serum cholesterol levels and suicide attempts in child and adolescent psychiatric inpatients

Associations between cholesterol and suicidal behavior in adolescent patients have not been explored in depth. In this study, 66 patients consecutively admitted to a psychiatric inpatient unit following attempted suicide were compared with a control group of 54 patients with no history of suicide attempts. The age range of the sample was from 8 to 18 years old. Cholesterol levels were significantly lower in attempted suicide patients than in controls (p < 0.02), supporting the hypothesis that lower cholesterol levels might be associated with suicidal behavior in patients with similar acute phase of their disorder.

Suicidality, impulsivity and aggression--is there a link to 5HIAA concentration in the cerebrospinal fluid?

In biological suicide research, low cerebrospinal fluid-5-hydroxyindolacetic acid (CSF-5HIAA) concentrations have been associated with suicidality, aggression and impulsivity. However, it frequently appears that the interpretation of existing study results is flawed. The analysis of various published findings suggests that contaminating factors like impulsivity or depressive symptoms in suicide attempters are often not taken into consideration at the time of suicide. The seemingly 'robust' association of low CSF-5HIAA concentration with 'suicidality' and 'aggression' is in fact rather weak. Reported associations of subgroups of suicidal behavior (e.g. violent suicide attempts) with low CSF-5HIAA concentrations are likely to represent somewhat premature translations of findings from studies that have flaws in methodology. Furthermore, the perception of 'suicidal behavior' as autoaggressive behavior or inwardly directed aggression in the view of the authors may not be useful in biological suicide research. The construct of aggressivity is insufficiently defined, resulting in difficulties to interpret empirical data. Some evidence exists, however, that reduced CSF-5HIAA concentrations might be related to certain depressive symptoms and changes in impulsivity. More carefully designed studies are required to overcome the existing methodological shortcomings.