Temperamental and Genetic Predictors of Suicide Attempt and Self-Mutilation

Abstract

Background and Aims: Literature findings mainly support the notion that suicide attempts (SA) and self-mutilating behavior (SMB) are distinct behaviors, although they may share common psychopathological features. In the present paper we aimed to identify behavioral phenotypes in patients with SA, SMB, or both (SAM) and to analyze the association with candidate genes. Methods: One hundred forty-two inpatients with a history of SA (n = 86), SMB (n = 22), and SAM (n = 39) were included in this study. Subjects were evaluated using the Tridimensional Personality Questionnaire (TPQ) and the Buss-Durkee Hostility Inventory (BDHI). Polymorphisms within serotonin transporter (SLC6A4, HTTLPR), catechol-O-methyl transferase (COMT, Val158Met), and tryptophan hydroxylase (TPH, 218C>A) were also analyzed. Results: Principal component factor analysis including the BDHI and TPQ produced 3 factors that could classify the 3 groups of patients with good sensitivity. However, only the ‘pure suicidal' factor had a sufficient positive predictive value. This factor was characterized by high levels of persistence (PS) and, to a lower extent, reward dependence. The distribution of genotypes was not different across patient groups for all polymorphisms, but the SS genotype of HTTLPR was significantly associated with the ‘self-mutilation' factor, characterized by high levels of hostile traits, novelty seeking, and harm avoidance. Conclusion: The results of the present study suggest that different and overlapping temperamental traits in suicidal and self-mutilating patients are present, although only high levels of PS could predict SA repetition. Finally, HTTLPR may mediate the risk for SMB through modulation of some temperamental traits.

Advancing a temporal framework for understanding the biology of nonsuicidal self- injury: An expert review

“…First, several studies have targeted a polymorphism of the serotonin-transporter linked promoter region (5-HTTLPR). No significant main effects of the 5-HTTLPR on the occurrence of NSSI were found in a sample of male prisoners (Gorodetsky et al, 2016) or between groups of adults receiving inpatient care who reported a history of suicide attempts or NSSI (Dell'osso et al, 2013). Steiger et al (2011) failed to find a relationship between variants of the 5-HTTLPR and self-harming behavior, defined as NSSI and/or suicidal behavior, in independent samples of adult females with eating disorders.…”

“…However, in the same study, high-function variants of the monoamine oxidase A (MAOA) gene were associated with increased risk of self-harming behavior (Steiger et al, 2011). With regard to polymorphisms of the catechol-O-methyl transferase (COMT) gene, no significant differences were found between groups of adults receiving inpatient care who reported a history of suicide attempts or engagement in NSSI (Dell'osso et al, 2013). In contrast, Bernegger et al (2018) found a haplotype of COMT polymorphisms (consisting of rs737865, rs6269, and rs4633) was associated with NSSI among adults with affective disorders.…”

Predictors for self‐directed aggression in Italian prisoners include externalizing behaviors, childhood trauma and the serotonin transporter gene polymorphism 5‐HTTLPR

“…High comorbidity has been observed between suicide attempts and self-mutilation (Dulit et al , 1994, Klonsky et al , 2013, Nelson & Grunebaum, 1971, Nock et al , 2006). Persistent self-mutilation may predict repeated suicide attempts (Dell'osso et al , 2013, Klonsky et al , 2013). …”