Monique Séguin

Impulsive-aggressive behaviours and completed suicide across the life cycle: a predisposition for younger age of suicide

BACKGROUND It is unclear whether the association between impulsive-aggressive behaviours and suicide exists across different ages. METHOD Via psychological autopsy, we examined a total of 645 subjects aged 11-87 years who died by suicide. Proxy-based interviews were conducted using the SCID-I & SCID-II or K-SADS interviews and a series of behavioural and personality-trait assessments. Secondarily, 246 living controls were similarly assessed. RESULTS Higher levels of impulsivity, lifetime history of aggression, and novelty seeking were associated with younger age of death by suicide, while increasing levels of harm avoidance were associated with increasing age of suicide. This effect was observed after accounting for age-related psychopathology (current and lifetime depressive disorders, lifetime anxiety disorders, current and lifetime substance abuse disorders, psychotic disorders and cluster B personality disorders). Age effects were not due to the characteristics of informants, and such effects were not observed among living controls. When directly controlling for major psychopathology, the interaction between age, levels of impulsivity, aggression and novelty seeking predicted suicide status while controlling for the independent contributions of age and these traits. CONCLUSIONS Higher levels of impulsive-aggressive traits play a greater role in suicide occurring among younger individuals, with decreasing importance with increasing age.

Familial Aggregation of Suicide Explained by Cluster B Traits: A Three-Group Family Study of Suicide Controlling for Major Depressive Disorder

OBJECTIVE There is substantial evidence suggesting that suicide aggregates in families. However, the extent of overlap between the liability to suicide and psychiatric disorders, particularly major depressive disorder, remains an important issue. Similarly, factors that account for the familial transmission of suicidal behavior remain unclear. Thus, through direct and blind assessment of first-degree relatives, the authors conducted a family study of suicide by examining three proband groups: probands who committed suicide in the context of major depressive disorder, living depressed probands with no history of suicidal behavior, and psychiatrically normal community comparison probands. METHOD Participants were 718 first-degree relatives from 120 families: 296 relatives of 51 depressed probands who committed suicide, 185 relatives of 34 nonsuicidal depressed probands, and 237 relatives of 35 community comparison subjects. Psychopathology, suicidal behavior, and behavioral measures were assessed via interviews. RESULTS The relatives of probands who committed suicide had higher levels of suicidal behavior (10.8%) than the relatives of nonsuicidal depressed probands (6.5%) and community comparison probands (3.4%). Testing cluster B traits as intermediate phenotypes of suicide showed that the relatives of depressed probands who committed suicide had elevated levels of cluster B traits; familial predisposition to suicide was associated with increased levels of cluster B traits; cluster B traits demonstrated familial aggregation and were associated with suicide attempts among relatives; and cluster B traits mediated, at least in part, the relationship between familial predisposition and suicide attempts among relatives. Analyses were repeated for severity of attempts, where cluster B traits also met criteria for endophenotypes of suicide. CONCLUSIONS Familial transmission of suicide and major depression, while partially overlapping, are distinct. Cluster B traits and impulsive-aggressive behavior represent intermediate phenotypes of suicide.

Suicide and no axis I psychopathology

BackgroundIt is unclear why approximately 10% of suicide completers seem to be psychiatrically normal. To better understand this issue, we studied suicide completers without an axis I diagnosis and compared them, on measures of psychopathology other than axis I, to normal controls and suicide cases with axis I psychopathology.Methods168 suicide cases were examined by way of a psychological autopsy with the best possible informant. Sixteen cases did not meet criteria for an axis I diagnosis; each of these cases was then age and gender matched to 52 suicide completers with an axis I disorder and 110 normal controls.ResultsFourteen of sixteen suicide cases without an axis I diagnosis had detectable abnormalities that were more similar to the axis I diagnosed suicide group than to a living group. Both suicide groups were similar in the total number of past suicide attempts, the total number of individuals with an axis II disorder, and similar scores on measures of impulsive-aggressive behaviors.ConclusionsThese findings suggest that most of the individuals who committed suicide and appeared psychiatrically normal after a psychological autopsy may probably have an underlying psychiatric process that the psychological autopsy method, as commonly carried out, failed to detect.

Patterns of co-morbidity in male suicide completers

BACKGROUND Psychiatric co-morbidity is thought to be an important problem in suicide, but it has been little investigated. This study aims to investigate patterns of co-morbidity in a group of male suicide completers. METHOD One hundred and fifteen male suicide completers from the Greater Montreal Area and 82 matched community controls were assessed using proxy-based diagnostic interviews. Patterns of co-morbidity were investigated using latent class analysis. RESULTS Three subgroups of male suicide completers were identified (L2 = 171.62, df = 2012, P < 0.05). they differed significantly in the amount of co-morbidity (Kruskal-Wallis chi2 = 71.227, df = 2. P < 0.000) and exhibited different diagnostic profiles. Co-morbidity was particularly found in subjects with disorders characterized by impulsive and impulsive-aggressive traits, whereas subjects without those traits had levels of co-morbidity which were not significantly different from those of controls (chi2 = 8.17, df = 4, P = 0.086). CONCLUSIONS Suicide completers can be divided into at least three subgroups according to co-morbidity: a low co-morbidity group, a substance-dependent group and a group exhibiting childhood onset of psychopathology.

Life trajectories and burden of adversity: mapping the developmental profiles of suicide mortality.

BACKGROUND Little is known about differential suicide profiles across the life trajectory. This study introduces the life-course method in suicide research with the aim of refining the longitudinal and cumulative assessment of psychosocial factors by quantifying accumulation of burden over time in order to delineate distinctive pathways of completed suicide. METHOD The psychological autopsy method was used to obtain third-party information on consecutive suicides. Life-history calendar analysis served to arrive at an adversity score per 5-year segment that was then cluster-analysed and correlated to define victim profiles. RESULTS Two distinct life trajectories emerged: (1) individuals who experienced childhood traumas, developmental adversity and little protection were more likely to present concurrent psychiatric and Axis II disorders; and (2) individuals who experienced less adversity but seemed more reactive to later major difficulties. CONCLUSIONS The life calendar approach presented here in suicide research adds to the identification of life events, distal and recent, previously associated with suicide. It also quantifies the burden of adversity over the life course, defining two distinct profiles that could benefit from distinct targeted preventive intervention.

Suicide and serotonin: study of variation at seven serotonin receptor genes in suicide completers.

Suicide is an important public health problem, accounting for a significant proportion of total mortality among young people, particularly males. There is growing and consistent evidence suggesting that genetic factors play an important role in the predisposition to suicide. Based on several lines of evidence supporting a reduced serotonergic neurotransmission in subjects who committed suicide, we investigated variation at genes that code for serotonin receptor 1B (5‐HTR1B), 1Dα (5‐HTR1Dα), 1E (5‐HTR1E), 1F (5‐HTR1F), 2C (5‐HTR2C), 5A (5‐HTR5A), and 6 (5‐HTR6) in a total sample of 106 suicide completers and 120 normal controls. No differences were observed in allelic or genotypic distributions between groups for any of the loci investigated. Moreover, further analysis according to suicide method or psychopathology also failed to reveal differences between groups. Our results do not support a substantial role of these serotonergic receptors in suicide completion.

Youth and young adult suicide: A study of life trajectory

OBJECTIVES Explore the unique developmental challenges and early adversity faced by youth and young adult who died of suicide. METHOD Sixty-seven suicide victims (SG) were compared with 56 living control with no suicidal ideations in the last year, matched for age, gender, and geographical region. Mixed methods were used: consensus DSM-IV diagnoses were formulated based on Structured Clinical Interview for DSM-IV (SCID)-I and -II interviews complemented by medical charts. Life calendar method was conducted with closest third party informant. Life-history calendar served to measure life events and adversity throughout the life course and were analyzed by attributing burden of adversity score per five-year segment, which was then cluster-analyzed to define suicide victim profiles. RESULTS During the last year, mood disorders, abuse and dependence disorders, and anxiety disorder were between 8 and 63 times more likely to be present in the suicide group. Between 0 and 4 years old, 50% of children in the SG were exposed to abuse, physical and/or sexual violence; 60% between 5 and 9 years old; and by the time they were 10-14 years old, 77% were exposed to these forms of violence. In the control group, the respective figures were 14%, 18% and 34%. In the suicide group, the trajectories leading to suicide are different as we observe two different subgroups, one with early-onset and one with later-onset of adversity. To a large extent, people in the suicide group were exposed to major adversity and they were more likely to present cumulative comorbid disorders.

Alpha 2A adrenergic receptor gene and suicide

Suicide is a complex trait resulting from the interaction of several predisposing factors, among which genes seem to play an important role. Alterations in the noradrenergic system have been observed in postmortem brain studies of suicide victims when compared to controls. The purpose of this study was to test the hypothesis that genetic variants of the alpha(2A) adrenergic receptor gene are implicated in suicide and/or have a modulatory effect on personality traits that are believed to mediate suicidal behavior. We studied a sample of suicides (N=110) and control subjects (N=130) for genetic variation at four loci, including three in the promoter region (g-1800t, c-1291 g and the g-261a) of the alpha(2A) adrenergic receptor gene, and a potentially functional locus, N251K, which leads to an amino acid change (asparagine to lysine). No significant differences were observed at the promoter loci in terms of allelic or genotypic distribution between suicides and controls. However, analysis of the functional polymorphism N251K revealed that the 251 K allele was only present among suicides, though only three suicide cases had this allele, two of which were homozygous. These results are preliminary. If confirmed, they suggest that variation at the alpha(2A) adrenergic receptor gene may play a role in a small proportion of suicide cases.

Wolfram Syndrome and Suicide: Evidence for a Role of WFS1 in Suicidal and Impulsive Behavior

There is evidence suggesting that subjects affected with the Wolfram syndrome (WFS) and normal carriers present an increased risk of psychiatric disorders, particularly depression and suicidal behavior. We investigated a possible role of the gene involved in WFS (WFS1) in the neurobiology of suicide and the potential modulatory effect on traits associated to suicidal behavior. Genetic variation at WFS1 (H611R, R456H, and I333V) was investigated in 111 suicide victims and 129 normal controls. Possible effects on psychopathology and behavioral traits were investigated in a subsample of suicide cases (N = 31) for whom phenotyping was carried out by means of structured psychiatric interviews and questionnaires adapted for psychological autopsies. We found a significantly higher frequency of the 611R/611R genotype in suicide completers as compared to controls (χ2 = 19.21, df=2, P = 0.001). Suicide completers with this genotype had higher scores on measures of impulsivity (t = −3.15, df = 15.3, P = 0.006); novelty seeking (NS) (t = −3.35, df = 13.8, P = 0.005); and conversely, lower scores of persistence (t = 2.4, df = 16.6, P = 0.028). Scores of impulsivity and NS remained higher in subjects with the associated genotype after adjusting for age, gender, and psychopathology. These results suggest a role for WFS1 in the pathophysiology of impulsive suicide, and are consistent with previous clinical reports suggesting an increased risk of suicidal behavior in WFS homozygotes and heterozygotes. However, these findings are preliminary and should be confirmed in independent samples.

Suicide cases in New Brunswick from April 2002 to May 2003: the importance of better recognizing substance and mood disorder comorbidity.

Objective: To investigate all suicide cases that occurred in New Brunswick in the 14 months spanning April 1, 2002, to May 31, 2003, to determine 6-month and lifetime prevalence rates of psychopathology in the deceased. Method: We used 2 psychological autopsy methods: direct proxy-based interviews and medical chart reviews, together with telephone contacts with informants. Consensus DSM-IV diagnoses were formulated by clinical panels on the basis of the Structured Clinical Interviews I and II for DSM-IV complemented by medical charts. Results: Of the 109 suicide deaths identified by the coroner at the time of the study, we were able to investigate 102. At time of death, 65% of the suicide victims had a mood disorder, 59% had a substance-related disorder, and 42% had concurrent mood and substance-related disorders. The lifetime prevalence of substance-related disorders among these suicide victims was 66%. Finally, 52% of the suicide victims presented with a personality disorder; one-half of these were of the cluster B type. Conclusions: Although treatment of depression has frequently been recognized as the focal point of clinically based suicide-prevention efforts, our results underscore substance-related disorders as a key dimension of completed suicide. Suicide-prevention programs should be designed to address this problem more directly.