Neurobiology of Impulsivity and Aggression As Substrates of Suicidal Behavior: A Narrative Focus on the Involvement of Serum Lipids

Abstract

Previous incidental findings of an increase of suicidal risk among subjects with low cholesterol levels have drawn attention to the role of lipids in suicidal behavior. To date, multiple lines of evidence acquired from clinical studies have confirmed an association between low cholesterol levels and suicidal behavior, but the involvement of dimensional traits including impulsivity and aggression in this association remains elusive. In this narrative review, we aimed to address and synthesize the literature regarding the involvement of lipids in the neurobiology of suicidal behavior and its underlying psychological substrates, impulsivity and aggression. An electronic database search was performed using different combinations of relevant keywords. Both preclinical and clinical studies matching the scope of this article were reviewed and filtered through an inspection of the abstracts to recruit the most suitable articles that contributed essential and substantial findings to the literature. Although subject characteristics and study designs vary across studies, current research has demonstrated that impulsivity and aggression might have shared neurobiologic substrates involved in altered serotonergic neurotransmission. Despite the association between low serum lipid levels and suicidal behavior being well documented, the involvement of lipid subtypes in the pathophysiology of impulsive and aggressive traits remains elusive. Further work is warranted to recognize the roles of lipids in neuronal membrane functions and serotonin metabolism, promote a greater appreciation of identifying biomarkers that could be used to determine at-risk individuals, and develop potential interventions to disrupt the pathogenesis of behavioral phenotypes of suicide.

Relationship between blood cholesterol and suicidal behaviour

“…Similarly, a literature review conducted by Troisi A. it reflects contradictory data, and therefore, it becomes obvious to the author that there are certain subgroups of vulnerable people who, unlike most people in the general population, are subject to adverse psychological and behavioural consequences associated with a low level of CH [76]. The authors of another literature review, who have covered the literature for 40 years, found more evidence of the existence of a connection, but still could not miss the contradictions [77]. There is conflicting information about the role of statins in suicidal behaviour.…”

“…There is conflicting information about the role of statins in suicidal behaviour. Several authors note that in patients treated with statins, the frequency of suicidal thoughts increased, but no connection was found with dietary habits, diets [77,78]. In a meta-analysis that studied methods of reducing cholesterol and the relationship with suicide, it was noted that statins do not affect suicide in any way, unlike nutrition [79].…”