The concept of violent suicide, its underlying trait and neurobiology: A critical perspective

Sleep and circadian rhythms in adolescents with attempted suicide

Sleep and circadian rhythm disorders are very common in adolescents and have been linked to suicidal ideation. However, little is known about adolescent sleep before a suicide attempt (SA). The objectives of this study were to compare the sleep of adolescents aged 13 to 18 over a period of 4 weeks before a SA compared to a non-SA group, then to analyze the association between sleep, support social and well-being based on information from validated questionnaires. In 2015, 250 adolescents were included, 55 were recruited the day after a SA in French hospitals (before SA evaluations were retrospective). Logistic regression analyzes showed that during school days, bedtime was equivalent in both groups, but sleep onset latency was significantly longer in SA (86 min vs. 52 min, p = 0.016), and wake-up time was earlier (6 h 22 vs. 6 h 47, p = 0.002), resulting in a shorter total sleep time of 44 min (OR = 0.76, CI 95% [0.61-0.93]) the month preceding SA. Adolescents with longer sleep time performed better on perceived psychological well-being (p = 0.005), relationship with parents (p = 0.011) and school environment (p < 0.001). Results indicate a significant change in the quantity and quality of adolescents' subjective sleep in the 4 weeks preceding SA requiring objective measures to study the predictive properties of sleep in SA.

Suicide trends in Denmark-An ecological study exploring suicide methods from 1995 to 2019

Suicide is a major public health problem and complex phenomenon, affecting many people around the world. However, the incidence of suicide varies by sex and age, which includes differences in the means used. Therefore, to implement effective preventative interventions, it is important to study these differences to design effective, preventative interventions. This study investigates the trends in suicide rates in Denmark from 1995 to 2019 by analysing changes based on sex, age, and the means used for suicide. Data on all suicide deaths in the study period were extracted from the Danish Register of Causes of Death, and data on the background population were obtained from Statistics Denmark. We used negative binomial regression models to analyse the data, and the obtained estimates as a logarithm of the rate ratios allowed us to compare the results across groups and years. An overall decline in Danish suicide rates was observed during the study period, with the exception of young females aged 15-29 years. The demographic composition did not change significantly, and suicide rates are still highest for males and the elderly aged 60+. Hanging, self-poisoning and firearms remain the most prevalent means of suicide. Suicide prevention initiatives are required, especially interventions targeting males and the elderly. Restricting access to the means of suicide for these groups with high fatality rates may help reduce the overall suicide rate. Moreover, more research is needed to understand the factors that lead to suicide and affect the choice of means, which should also include studying the effects of different suicide prevention strategies on males and females from different age groups.

Longitude-based time zone partitions and rates of suicide

BACKGROUND

Increasing evidence suggests that conditions with decreased morning and increased evening light exposure, including shift work, daylight-saving time, and eveningness, are associated with elevated mortality and suicide risk. Given that the alignment between the astronomical, biological, and social time varies across a time zone, with later-shifted daylight exposure in the western partition, we hypothesized that western time zone partitions would have higher suicide rates than eastern partitions.

METHODS

United States (U.S.) county-level suicide and demographic data, from 2010 to 2018, were obtained from a Centers for Disease Control database. Using longitude and latitude, counties were sorted into the western, middle, or eastern partition of their respective time zones, as well as the northern and southern halves of the U.S. Linear regressions were used to estimate the associations between suicide rates and time zone partitions, adjusting for gender, race, ethnicity, age group, and unemployment rates.

RESULTS

Data were available for 2872 counties. Across the U.S., western partitions had statistically significantly higher rates of suicide compared to eastern partitions and averaged up to two additional yearly deaths per 100,000 people (p < .001).

LIMITATIONS

Ecological design and limited adjustment for socioeconomic factors.

CONCLUSIONS

To our knowledge, this is the first study of the relationship between longitude-based time zone partitions and suicide. The results were consistent with the hypothesized elevated suicide rates in the western partitions, and concordant with previous reports on cancer mortality and transportation fatalities. The next step is to retest the hypothesis with individual-level data, accounting for latitude, photoperiodic changes, daylight-saving time, geoclimatic variables, physical and mental health indicators, as well as socioeconomic adversity and protection.

Conventional and assisted suicide in Switzerland: Insights into a divergent development based on cancer-associated self-initiated deaths

BACKGROUND

We tested the hypothesis of supporters of assisted dying that assisted suicide (AS) might be able to prevent cases of conventional suicide (CS).

METHODS

By using data from the Federal Statistical Office, we analyzed the long-term development of 30,756 self-initiated deaths in Switzerland over a 20-year period (1999-2018; CS: n = 22,018, AS: n = 8738), focusing on people suffering from cancer who died from AS or CS.

RESULTS

While cancer was the most often listed principal disease for AS (n = 3580, 41.0% of AS cases), cancer was listed in only a small minority of CS cases (n = 832, 3.8% of CS cases). There was a significant increase in the absolute number of cancer-associated AS cases: comparing four 5-year periods, there was approximately a doubling of cases every 5 years (1999-2003: n = 228 vs.2004-2008: n = 474, +108% compared with the previous period; 2009-2013: n = 920, +94%; 2014-2018: n = 1958, +113%). The ratio of cancer-associated AS in relationship with all cancer-associated deaths increased over time to 2.3% in the last observation period (2014-2018). In parallel, the numbers of cancer-associated CS showed a downward trend only at the beginning of the observation period (1999-2003, n = 240 vs. 2004-2008, n = 199, -17%). Thereafter, the number of cases remained stable in the subsequent 5-year period (2009-2013, n = 187, -6%), and increased again toward the most recent period (2014-2018, n = 206, +10%).

CONCLUSION

The assumption that, with the increasingly accessible option of AS for patients with cancer, CS suicide will become "superfluous" cannot be confirmed. There are strong reasons indicating that situations and circumstances of cancer-associated CS are different from those for cancer-associated AS.

Is It Correct to Consider Caustic Ingestion as a Nonviolent Method of Suicide? A Retrospective Analysis and Psychological Considerations

BACKGROUND

Suicide methods chosen by victims are particularly critical in suicide risk research. To differentiate suicide deaths, it is usual to categorize them as violent and nonviolent depending on the detrimental method chosen by the victims. Caustic ingestion, for example, is traditionally considered as a nonviolent suicide method. It results in severe consequences for the human body and it is associated with high levels of lethality.

METHODS

In this study, we retrospectively analyzed suicides that occurred between 1993 and 2021 in Milan (Italy) and that underwent autopsy. We compared a sample of 40 victims that ingested caustic substances with a sample of 460 victims of other chemical ingestion, and a sample of 3962 victims from violent suicide. Univariate analyses and univariate logistic regression models were performed. Suicides from caustic poisoning were significantly older, had a higher mean number of diseases and were more affected by psychiatric diseases compared to other chemical ingestion victims. By contrast, caustic suicides, compared to violent suicides, had a more balanced gender ratio, a higher mean number of diseases, were more affected by psychiatric diseases, had a higher rate of complex suicides (more than one modality), and had victims who died more frequently inside instead of outside. In logistic regression models, age was the only feature differentiating caustic from other chemical ingestion suicides while the features differentiating caustic from violent suicides were gender, mean number of diseases and suicide place.

CONCLUSIONS

Suicides by caustic ingestion showed substantial differences compared to violent suicides, with a higher severe profile. However, some differences were reported comparing caustic ingestion to other chemical ingestion as well. Thus, we argue whether it is more appropriate to differentiate the suicidal ingestion of caustics from both violent and nonviolent suicide methods.

Gene Expression Analysis in Postmortem Brains from Individuals Who Died by Suicide: A Systematic Review

Around the world, more the 700,000 individuals die by suicide every year. It is necessary to understand the mechanisms associated with suicidal behavior. Recently, an increase in gene expression studies has been in development. Through a systematic review, we aimed to find a candidate gene in gene expression studies on postmortem brains of suicide completers. Databases were systematically searched for published studies. We performed an online search using PubMed, Scopus and Web of Science databases to search studies up until May 2023. The terms included were "gene expression", "expressed genes", "microarray", "qRT-PCR", "brain samples" and "suicide". Our systematic review included 59 studies covering the analysis of 1450 brain tissues from individuals who died by suicide. The majority of gene expression profiles were obtained of the prefrontal cortex, anterior cingulate cortex, dorsolateral prefrontal cortex, ventral prefrontal cortex and orbital frontal cortex area. The most studied mRNAs came of genes in glutamate, γ-amino-butyric acid and polyamine systems. mRNAs of genes in the brain-derived neurotrophic factor, tropomyosin-related kinase B (TrkB), HPA axis and chemokine family were also studied. On the other hand, psychiatric comorbidities indicate that suicide by violent death can alter the profile of mRNA expression.

Time trends and geographical patterns in suicide among Greenland Inuit

BACKGROUND

Between 1980 and 2018 Greenland has had one of the highest suicide rates in the world with an average rate of 96 suicides per 100,000 people annually. The aim of this study is to investigate suicide rates in Greenland according to age, birth cohort, period, sex, place of residence and suicide method from 1970 until 2018.

METHODS

Suicide rates were examined using register and census data from 1970-2018 among Greenland Inuit. Rates were calculated by Poisson regression in Stata and by use of Excel. In analyses of the period trends, rates were standardized according to the World Standard Population 2000-2025.

RESULTS

The suicide rate has been declining since a peak at 120 suicides per 100,000 people annually in the 1980s but remained high at a rate of 81.3 suicides per 100,000 people annually from 2015-2018. Descriptive analyses point to the decrease in male suicides as the primary factor for the overall decreasing rates while the rate among women has been increasing. Simultaneously, the proportion of women who used a violent suicide method increased from 60% in 1970-1979 to 90% in 2010-2018. The highest rates are seen among young people, especially young men aged 20-24 years and youth suicide rates increased with later birth cohorts. When the rates started to increase in the 1980s both the capital Nuuk and East Greenland had the highest rates. Since then, the rate in Nuuk has declined while the rate in East Greenland was three times the national rate from 2015-2018.

CONCLUSIONS

From 1970 to 1989 the suicide rate increased from 28.7 to 120.5 per 100,000 people mirroring a rapid societal transition in the post-colonial period. The rate has slowly declined from the peak in the 1980s but remains at a very high level. Young people in general are at risk, but the steady increase in the rate among women is worrying and there is a need to investigate underlying causes for this development.

Hypothalamic-prolactin axis regulation in major depressed patients with suicidal behavior

BACKGROUND

So far, little is known about the control of hypothalamic-prolactin axis activity by dopamine (DA) and thyrotropin-releasing hormone (TRH) in depressed patients with suicidal behavior disorder (SBD).

METHODS

We evaluated prolactin (PRL) responses to apomorphine (APO; a DA direct receptor agonist) and 0800 h and 2300 h protirelin (TRH) tests in 50 medication-free euthyroid DSM-5 major depressed inpatients with SBD (either current [n = 22], or in early remission [n = 28]); and 18 healthy hospitalized controls (HCs).

RESULTS

Baseline (BL) PRL levels were comparable across the three diagnostic groups. SBDs in early remission did not differ from HCs regarding PRL suppression to APO (PRLs), PRL stimulation to 0800 h and 2300 h TRH tests (∆PRL), and ∆∆PRL values (difference between 2300 h-∆PRL and 0800 h-∆PRL values). Current SBDs showed lower PRLs and ∆∆PRL values than HCs and SBDs in early remission. Further analyses revealed that current SBDs with a history of violent and high-lethality suicide attempts were more likely to exhibit co-occurrence of low ∆∆PRL and PRL_S values.

CONCLUSIONS

Our results suggest that regulation of the hypothalamic-PRL axis is impaired in some depressed patients with current SBD, particularly those who have made serious suicide attempts. Considering the limitations of our study, our findings support the hypothesis that decreased pituitary D2 receptor functionality (possibly adaptive to increased tuberoinfundibular DAergic neuronal activity) together with decreased hypothalamic TRH drive might be a biosignature for high-lethality violent suicide attempts.

Investigating the Clinical Profile of Suicide Attempters Who Used a Violent Suicidal Means

In our study, we aimed to explore the profile of the high-risk subgroup of suicide attempters that used a violent means compared to suicide attempters that chose a non-violent suicide means. Therefore, we recruited a sample of inpatients with recent suicide attempts in three psychiatric hospitals in Thuringia, Germany. We used a structured clinical interview to assess the psychiatric diagnoses, sociodemographic data, and characteristics of the suicide attempt. Furthermore, we used several validated clinical questionnaires to measure suicidal ideations, suicide intent, depression severity, hopelessness, impulsivity, aggression, anger expression, and childhood trauma. We compared 41 individuals using violent means to 59 using non-violent means with univariate and multivariate statistical analyses. We found significantly (corrected for multiple comparisons) higher levels of impulsivity-related sensation-seeking in violent suicide attempters in univariate and multivariate analyses, and additionally in anger expression directed inward at an uncorrected statistical threshold. Besides that, there were no significant differences between the two groups. We assume that underlying neurocognitive mechanisms, such as impaired decision-making processes and/or differences in risk/loss assessment, could explain the higher levels of questionnaire-based sensation-seeking in subjects who use violent suicide means. Further research is needed, including neuroimaging and biochemical techniques, to gain more insight into the mechanisms underlying the choice of a suicidal means.

The impact of daylight on suicide rates

Since Durkheim and Morselli found a spring peak in suicides in the late 19th century, researchers have presented possible explanations, including daylight variation, for this seasonal pattern. Our identification strategy exploits the idiosyncratic variation in daylight within Norwegian regions, arising from the country's substantial latitudinal range. We use full population data for a period of 45 years in a pre-registered research design. We find a small and non-significant relationship: One extra hour of daylight increases the suicide rate by merely 0.75 % (95 % CI: -0.4 % to 1.9 %).

Accelerated epigenetic aging in suicide attempters uninfluenced by high intent-to-die and choice of lethal methods

Suicide attempts (SA) are associated with excess non-suicidal mortality, putatively mediated in part by premature cellular senescence. Epigenetic age (EA) estimators of biological age have been previously demonstrated to strongly predict physiological dysregulation and mortality risk. Herein, we investigate if violent SA with high intent-to-die is predictive of epigenetics-derived estimates of biological aging. The genome-wide methylation pattern was measured using the Illumina Infinium Methylation EPIC BeadChip in whole blood of 88 suicide attempters. Subjects were stratified into two groups based on the putative risk of later committed suicide (low- [n = 58] and high-risk [n = 30]) in dependency of SA method (violent or non-violent) and/or intent-to-die (high/low). Estimators of intrinsic and extrinsic EA acceleration, one marker optimized to predict physiological dysregulation (DNAmPhenoAge/AgeAccelPheno) and one optimized to predict lifespan (DNAmGrimAge/AgeAccelGrim) were investigated for associations to severity of SA, by univariate and multivariate analyses. The study was adequately powered to detect differences of 2.2 years in AgeAccelGrim in relation to SA severity. Baseline DNAmGrimAge exceeded chronological age by 7.3 years on average across all samples, conferring a mean 24.6% increase in relation to actual age. No individual EA acceleration marker was differentiated by suicidal risk group (p > 0.1). Thus, SA per se but not severity of SA is related to EA, implicating that excess non-suicidal mortality in SA is unrelated to risk of committed suicide. Preventative healthcare efforts aimed at curtailing excess mortality after SA may benefit from acting equally powerful to recognize somatic comorbidities irrespective of the severity inherent in the act itself.

Race, Age, and Lack of Insurance Increase Risk of Suicide Attempt in Trauma Patients

OBJECTIVE

The overall rate of suicide between 1999 and 2017 increased by 33% in the United States. We sought to examine suicide attempts in the trauma patient population, hypothesizing that in adult trauma patients race and lack of insurance status would be predictors of suicide attempt.

METHOD

The Trauma Quality Improvement Program (2010-2016) was queried for trauma patients ≥18 years old. The primary outcome was suicide attempt. A multivariable logistic regression model was performed including covariates that influence risk of suicide attempt.

RESULTS

From 1,403,466 adult trauma admissions, 16,263 (1.2%) patients attempted suicide. Death after suicide attempt occurred in 30.2% of patients. Independent predictors of suicide attempt were age < 40 years old (odds ratio [OR] = 1.46, 95% confidence interval [CI] [1.41, 1.51], p < .001) and no insurance (OR = 1.92, 95% CI [1.85, 2.00], p < .001). Black (vs. White) race was associated with decreased risk of suicide attempt (OR = 0.63, 95% CI [0.60, 0.67], p < .001). Hispanic (versus non-Hispanic) patients demonstrated lower associated risk of suicide attempt by gun (OR = 0.50, 95% CI [0.45, 0.54], p < .001), while Asian (vs. White) patients exhibited higher risk of suicide attempt overall (OR = 1.25, 95% CI [1.12, 1.39], p < .001) and more specifically by knife (OR = 2.55, 95% CI [2.16, 3.00], p < .001).

CONCLUSIONS

Age younger than 40 years and lack of insurance were associated with higher risk of suicide attempt in adult trauma patients. Asian race was associated with the highest risk of suicide, with >2.5 times increased risk of attempt by knife. Awareness of these demographic-specific risk factors for suicide attempt, and in particular violent mechanisms of suicide attempt, is critical to implementation of effective suicide prevention efforts.HighlightsAge younger than 40 and no insurance were associated with risk of suicide attempt.Black (vs. White) race was associated with decreased risk of suicide attempt.Asian race was associated with an increased risk of suicide attempt with a knife.

Genetics and Brain Transcriptomics of Completed Suicide

OBJECTIVE

The authors sought to study the transcriptomic and genomic features of completed suicide by parsing the method chosen, to capture molecular correlates of the distinctive frame of mind of individuals who die by suicide, while reducing heterogeneity.

METHODS

The authors analyzed gene expression (RNA sequencing) from postmortem dorsolateral prefrontal cortex of patients who died by suicide with violent compared with nonviolent means, nonsuicide patients with the same psychiatric disorders, and a neurotypical group (total N=329). They then examined genomic risk scores (GRSs) for each psychiatric disorder included, and GRSs for cognition (IQ) and for suicide attempt, testing how they predict diagnosis or traits (total N=888).

RESULTS

Patients who died by suicide by violent means showed a transcriptomic pattern remarkably divergent from each of the other patient groups but less from the neurotypical group; consistently, their genomic profile of risk was relatively low for their diagnosed illness as well as for suicide attempt, and relatively high for IQ: they were more similar to the neurotypical group than to other patients. Differentially expressed genes (DEGs) associated with patients who died by suicide by violent means pointed to purinergic signaling in microglia, showing similarities to a genome-wide association study of Drosophila aggression. Weighted gene coexpression network analysis revealed that these DEGs were coexpressed in a context of mitochondrial metabolic activation unique to suicide by violent means.

CONCLUSIONS

These findings suggest that patients who die by suicide by violent means are in part biologically separable from other patients with the same diagnoses, and their behavioral outcome may be less dependent on genetic risk for conventional psychiatric disorders and be associated with an alteration of purinergic signaling and mitochondrial metabolism.

A Descriptive Cohort of Suicidal Cancer Patients: Analysis of the Autopsy Case Series from 1993 to 2019 in Milan (Italy)

Suicide in cancer patients has always been a subject of clinical studies, but the contribution of forensic pathology to this phenomenon is poorly reported. With the aim of at least partially filling this gap in information, at the Institute of Forensic Medicine of Milan, Italy, we assessed all suicides that occurred in cancer patients. A descriptive and retrospective analysis was carried out by examining the database of the Institute and autopsy reports. We included 288 suicide cases with proven cancer diseases. For each suicide, sex, age, country of origin, body area affected by cancer, further pathological history, medications, previous suicide attempts and suicidal communications, as well as the place where the suicide occurred, were assessed. Furthermore, from a forensic point of view, we considered the chosen suicide method and any involved means. The majority of cases were male older adults affected by lung, colon and prostate cancer. Violent suicide methods were prevalent, and the most represented suicide method was falling from height regardless of the body area affected by cancer. Such data may be of clinical use for clinicians engaged in the front lines in order to address suicide risk prevention strategies among cancer patients.

Sleep complaints are associated with increased suicide risk independently of psychiatric disorders: results from a national 3-year prospective study

Prior research suggests that sleep disturbances are associated with increased risk of suicide. However, sleep disturbances are associated with a wide range of psychiatric disorders, and it is unknown whether this association is independent of psychopathology. In a large nationally representative prospective survey, the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), we used structural equation modeling to examine the shared and specific effects of three sleep complaints (i.e., trouble falling asleep, early morning awakening, and hypersomnia) on the 3-year occurrence of attempting suicide. Because psychiatric disorders increase the risk of suicide attempt almost exclusively through a general psychopathology factor representing their shared effect, covariates included that factor, prior history of suicide attempt, and a wide range of sociodemographic and clinical characteristics. The 3-year prevalence rate of suicide attempt was 0.6% (n = 241). Compared with participants who did not attempt suicide between the two waves, those who did reported significantly more frequently having trouble falling asleep (44.6% vs. 16.6%), early morning awakening (38.9% vs. 12.7%), and hypersomnia (35.0% vs. 10.7%). Following adjustments, effects of sleep complaints on this risk were significant and exerted almost exclusively through a general sleep complaints factor representing the shared effect across all sleep complaints. There were no residual associations of any individual sleep complaint with attempting suicide above that association. Sleep complaints are associated with an increased risk of attempting suicide independently of psychopathology, and should be included in suicide risk assessments as these symptoms may provide targets for reducing the risks of suicidal behaviors.

High-lethality of suicide attempts associated with platelet to lymphocyte ratio and mean platelet volume in psychiatric inpatient setting

OBJECTIVES

A wide range of potential psychosocial, biological, genetic and environmental factors may interact with each other in determining suicidal behaviours. The aim of this study was to evaluate several biological parameters referred to the complete blood count values in 259 suicide attempters (SA) and 164 non-suicide attempters (control group), according to the lethality of suicidal behaviour.

METHODS

After attempting suicide, subjects were admitted to the emergency ward of the IRCCS Ospedale Policlinico San Martino and later to the section of Psychiatry from 1 January 2014 to 31 June 2019. Socio-demographic and clinical characteristics, as well as blood cells, were collected.

RESULTS

Individuals with high-lethality suicide attempts had a higher number of neutrophils, mean platelet volume, neutrophil-lymphocyte ratio, platelet-lymphocyte ratio, and lower number of lymphocytes relative to both those with low-lethality suicide attempts and control group. After regression analysis, only the mean platelet volume and platelet to lymphocyte ratio resulted associated with a high-lethality suicide attempt (HLSA).

CONCLUSIONS

Our findings provide potential and useful peripheral biological markers able to help clinicians in understanding the complex phenomenon of suicide. However, further studies are needed to confirm the present findings.

Risky decision-making in suicide attempters, and the choice of a violent suicidal means: an updated meta-analysis

BACKGROUND

Studies showed disadvantageous decision-making in suicide attempters. The present meta-analysis aims to examine the stability of these findings and related questions.

METHODS

EMBASE and Pubmed databases were searched for studies published between 01/01/2000 and 01/01/2020 with an additional search through bibliographical references. English or French articles published in peer-reviewed journals, reporting quantitative task-based measures of decision-making in suicide attempters were included: 3,582 records were identified, 33 full-text articles screened, and 21 articles finally included.

RESULTS

All studies were conducted in mood disorders; 18 used the Iowa Gambling Task (IGT) and 3 the Cambridge Gamble Task (CGT). With the IGT, suicide attempters showed riskier choices than patient controls (Hedges' g=-0.28 95%CI (-0.44 - -0.12)) and healthy controls (g=-0.54 (-0.83 - -0.25)) with no significant difference between control groups. The difference between suicide attempters and patient controls was not related to age group, mood disorder type, author, or research center while an effect of time of publication was found (p=0.006). Poorer performance was also found in suicide attempters compared to patient controls when using the CGT (g=-0.57 95%CI (-0.82 - -0.31)). Suicide attempters who used a violent means showed poorer IGT performance than those who used a non-violent means (3 studies).

LIMITATION

Limited number of studies outside mood disorders. No data to calculate a gender effect.

CONCLUSION

The present meta-analysis confirmed riskier decision-making in suicide attempters. Although group differences appear to be of modest effect size in general, they were particularly marked in the subgroup of those who used a violent suicidal means.

Impulsivity as a Risk Factor for Suicide in Bipolar Disorder

The accurate assessment of suicide risk in psychiatric, especially affective disorder diagnosed patients, remains a crucial clinical need. In this study, we applied temperament and character inventory (TCI), Barratt impulsiveness scale 11 (BIS-11), PEBL simple reaction time (SRT) test, continuous performance task (CPT), and Iowa gambling task (IGT) to seek for variables linked with attempted suicide in bipolar affective disorder group (n = 60; attempters n = 17). The main findings were: strong correlations between self-report tool scores and objective parameters in CPT; the difference between attempters and non-attempters was found in the number of correctly responded trials in IGT; only one parameter differed between attempters and non-attempters in BPI diagnosis; and no significant differences between suicide attempters and non-attempters in TCI, BIS-11, and SRT were found. These justify the conclusion that impulsivity itself is not a strong predictor, and used as a single variable might not be sufficient to indicate the high suicide risk group among bipolar patients.

Meteorological Variables and Suicidal Behavior: Air Pollution and Apparent Temperature Are Associated With High-Lethality Suicide Attempts and Male Gender

This study analyzed the impact of meteorological variables and high-lethality suicide attempts (HLSA) to assess a potential time shift of HLSA affected by climate evolution to predict the suicide attempt cases over different periods of the year. After attempting suicide, 225 subjects were admitted to the emergency ward of the IRCCS Ospedale Policlinico San Martino and later to the psychiatric unit from March 2016 to July 2018. Socio-demographic and clinical characteristics as well as the meteorological variables were collected. The Mann-Kendall test as well as redundancy and cross-correlation analyses were performed to analyze the trends, statistically correlations, and correspondence of the trends, respectively between suicidal behaviors and climatic factors. Sixty-seven (29.8%) committed a HLSA. Our findings indicate a significant association between HLSA and male gender and apparent temperature with a strong correlation of 75% with a phase shift of -1 month. Solar radiation and air pollution (PM_2.5) have a positive correlation of 65 and 32%, respectively, with a zero-time lag. Limitations include that the data are limited to a single hospital; psychological factors, or other clinical variables that could be ruled out as a trigger have not been considered. Meteorological variables may not mirror the temperature that the patient is exposed to due to the air conditioning systems. Exploring those environmental factors associated with HLSA in a more detailed manner could lead to early intervention and prevention strategies for such distressing admissions.

Completed Suicide With Violent and Non-violent Methods by the Elderly in Rural China: A Psychological Autopsy Study

Background: Late-life suicide is a severe public health problem in rural China; however, knowledge regarding the specific characteristics and risk factors for completed suicide via violent and non-violent methods among elderly individuals in rural China is limited. Methods: Subjects aged 60 years or older were selected from rural areas in Shandong, Hunan, and Guangxi provinces in China. This study was a 1:1 matched case-control design conducted by using the psychological autopsy method. Results: According to the univariate analyses, the presence of mental disorder, higher degree of depression, loneliness, lack of social support, hopelessness, impulsivity, and increased quantity of life events were associated with suicide in both violent and non-violent methods. For violent suicide, another risk factor was the lack of pesticides at home. For non-violent suicide, other risk factors were not currently married, family suicide history, and alcohol use disorder (P < 0.05). Variables that remained in the logistic regression model were the severity of depressive symptoms for both violent and non-violent suicide. For non-violent suicide, the degree of hopelessness was another independent risk factor. In addition, violent suicides were more likely to lack pesticides at home, choose the spring season and have an increased quantity of life events than those who died by suicide via non-violent methods. Conclusion: The major risk factor for both violent and non-violent suicide was the severity of depressive symptoms. Suicide prevention measures that focus on depression among this vulnerable population are urgently needed. Moreover, the characteristics of suicides via violent methods differed from those via non-violent methods among elderly individuals. Suicide prevention efforts should be tailored to the specific characteristics of the different suicide methods utilized by older adults in rural areas.

Monoamino Oxidase A Gene Single-Nucleotide Polymorphisms and Methylation Status and the Risk of Violent Suicide Attempts in Affective Disorder Patients

Background: When investigating the neurobiology of suicidal behavior, Monoamino Oxidase A (MAOA) is one of the prime suspects to consider. Interestingly, MAOA dysregulation has also been associated with violent behavior in previous publications. In the present study, we aimed to establish an association between polymorphisms of the MAOA gene and methylation status of the MAOA gene Exon I, and suicide attempts with violent methods in a sample of affective disorder patients. Methods: Eight hundred fourteen Caucasian affective disorder patients were assessed at the Department of Psychiatry and Psychotherapy of the Medical University Vienna, the Karl Landsteiner University for Health and Science and Zentren für seelische Gesundheit, BBRZ-Med Leopoldau. An assemblage of psychiatric interviews was performed (e.g., SCAN, HAMD, SBQ-R, CTQ) and DNA samples of peripheral blood cells were collected for Sequenom MassARRAY® iPLEX Gold genotyping and Multiplexed and Sensitive DNA Methylation Testing. Results: Female affective disorder patients with a history of violent suicide attempt were found to have a significantly increased frequency of the AA genotype in the rs5906957 single nucleotide polymorphism (p = 0.003). Furthermore, the MAOA gene exon I promoter region showed significantly decreased methylation in female violent suicide attempter(s) as opposed to female affective disorder patients who had no history of suicide attempt or no history of suicide attempt with violent method. Limitations: The small sample size hampers to reveal small genetic effects as to be expected in psychiatric disorders. Conclusions: This study offers promising findings about associations between the MAOA gene and violent suicide especially in women.

Sex-dependent grades of haematopoietic modulation in patients with major depressive episodes are associated with suicide attempts

Suicide is the leading cause of non-natural death worldwide, and major depressive disorder (MDD) is the mood disorder with the highest prevalence among individuals with suicidal behaviour (SB). The role of inflammation and immunomodulation in mood disorders has raised interest in recent years, as inflammation biomarkers have been reported to be increased in mood disorder patients, suggesting a role of inflammation in their pathogenesis. The influence of inflammation on the haematopoietic production is well known; however, a comprehensive study of the haematopoietic production in patients with major depressive episodes (MDE) is lacking. We examined global haematopoietic parameters from complete blood counts (CBC) of patients with MDE, in search of prognostic patterns. MDE patients presented differences in several CBC parameters, differences that were clearly pronounced and/or significant in concurrence with suicide attempts (SA). Red and white blood cell lineage parameters were affected, suggesting general haematopoietic modulation or imbalance. We observed distinct haematological parameter changes in women versus men, with men presenting milder alterations than women. Interestingly, we found that the List of Threatening Experiences (LTE) score, but not the Childhood Trauma Questionnaire (CTQ), was associated with the haematopoietic alterations observed exclusively in women and, more importantly, served as a parameter to stratify female MDE patients based on concurrence or non-concurrence with SA. In conclusion, grades of haematopoietic modulation in MDE patients are associated with absence or presence of SA. Haematopoietic manifestations differ between men and women and, in the latter, are markedly influenced by late, and not early, traumatic events.

Rates, characteristics and manner of cannabis-related deaths in Australia 2000-2018

BACKGROUND

The most commonly used illicit substance worldwide is cannabis. To date, no national level study of cannabis-related death has been undertaken in Australia. The current study aimed to investigate the rates, characteristics and manner of cannabis-related deaths recorded in Australia (2000-2018).

METHODS

A retrospective case review of medicolegal files was undertaken through the National Coronial Information System (NCIS) (1/07/2000-31/12/2018).

RESULTS

A total of 559 cases were identified, with a mean age of 35.8 years, 81.2% were male. The crude mortality rate per 100,000 people ranged between 0.10 (CI = 0.06-0.15) and 0.23 (CI = 0.17-0.30). The manner of deaths were: accidental injury (29.9%), suicide (25.0%), polysubstance toxicity (17.0%), natural disease (16.1 %), natural disease and drug effect/toxicity (7.9%), assault (3.0%) and unascertained (1.1%). No deaths were solely due to cannabis toxicity. Men were over-represented in this group and were three times as likely to die of accidental injury than women who died from cannabis-related deaths. Motor vehicle accidents were the leading cause of accidental injury. Cardiovascular (14.3%) and respiratory conditions (9.7%) were the most common disease types recorded in cause of death. The median Δ-9-tetrahydrocannabinol blood concentration was 0.008 mg/L (range 0.0005-19.00 mg/L). Other drugs were cited in the cause of death alongside cannabis (81.4%), the most common being alcohol (47.2%).

CONCLUSIONS

Low all-cause crude mortality rates remained relatively stable over the study period. No deaths were due to direct cannabis toxicity, but death due to accidental injury was prominent.

Predictors of relapse in high lethality suicide attempters: a six-month prospective study

BACKGROUND

This study is aimed to investigate the association between clinical, metabolic, inflammatory and environmental (photoperiod defined as daily sunlight exposure) parameters and suicide re-attempts after the index suicide attempt. Possible predictors of suicide re-attempts were also explored.

METHODS

Overall, 432 subjects with suicide attempts, of which 79 relapsed within the following six months were included in this prospective study. We adopted the Joiner's definition of suicide lethality, as "the acquired ability to enact lethal self-injury". The Cox regression was used to test the association between the mentioned variables and Kaplan-Meier plots showed the trend of suicide re-attempts.

RESULTS

Among participants, 30.8% committed a high-lethality suicide attempt. Cox regression confirmed the association between lifetime suicide attempts and number of suicide attempts in the study time-frame and suicide-reattempts. The longer photoperiod (Spring/Summer) was associated with suicide re-attempts, particularly patients with admission in June/July for the index event. Total cholesterol (TC), low-density lipo-protein cholesterol and c-reactive protein serum levels were significantly associated with suicide re-attempts but Cox regression confirmed only the association between lower TC serum levels and suicide re-attempt.

LIMITATIONS

Patients' seasonal environment, psychological factors, presence of acute life-events fostering the suicidal crisis and detailed medical history have been not investigated. Findings were derived from a single psychiatric unit.

CONCLUSIONS

Lifetime suicide attempts, higher number of previous suicide attempts, lower total cholesterol levels, and suicide attempt during longer photoperiod were significant predictors of suicide re-attempts. Further studies are needed in order to better characterize single- vs. multiple suicide attempter's profiles.

Correlates of violent suicide attempts in patients with bipolar disorder

BACKGROUND

Suicide is one of the leading causes of death in bipolar disorder (BD); violent suicide attempts are associated with the highest level of lethality. We aimed to evaluate factors related to the risk of violent suicide in a large naturalistic sample of patients with BD; in addition, we analyzed the rates of lifetime suicide attempts and the variables associated with suicidal behavior.

METHODS

We recruited 847 patients with BD. Patients were grouped according to whether they had a lifetime history of suicide attempts and, among suicide attempters, subjects who had used a violent suicide method were compared with those who had attempted suicide with a nonviolent method. Comparisons were performed using χ2 tests for categorical variables and ANOVA for continuous variables. Logistic regression (LogReg) was used to identify explanatory variables associated with violent suicide attempts (dependent variable).

RESULTS

Two hundred and two patients (24%) had a lifetime history of suicide attempts. Subjects with at least one lifetime suicide attempt showed longer duration of illness (22.4±14.1 years vs 19.9±14.2 years: p 0.028), more lifetime hypomanic episodes (3.3±4.3 vs 2.3±3.1: p0.001), more lifetime depressive episodes (6.0±4.4 vs 4.7±4.1: p<0.001), higher rates of lifetime psychiatric comorbidities (50.0% vs 41.3%: p 0.029), higher rates of lifetime medical comorbidities (58.0% vs 48.9%: p 0.028) and higher rates of reduced HDL cholesterol (46.2% vs 36.7%: p 0.030). Among suicide attempters, fifty-two patients (30.6%) attempted suicide with a violent method. We found more men in the group of violent suicide attempters than in the group of nonviolent suicide attempters (65% vs 28%; p: <0.001). Moreover subjects with previous violent attempts showed higher mean values of weight (80.5±18.3 vs 69.4±14.7: p<0.001), body mass index (27.8±5.6 vs 25.2±4.7: p<0.003) and waist circumference (98.7±18.5 vs 92.4±14.3: p 0.032). The LogReg analysis confirmed the association of violent attempts with male gender (p: <0.001; Phi: 0.35) and higher waist circumference (p: <0.001; Cohen's d: 0.39).

LIMITATIONS

In our research we analyzed lifetime suicide attempts, but the sample does not include completed suicides, meaning that we are unable to test whether the results are generalizable to suicide deaths. Moreover, some relevant variables, such as medical comorbidities/metabolic parameters at the time of suicide attempts and previous medication, were not collected. Another limitation concerns the heterogeneity of recruited patients in terms of clinical characteristics (e.g.: medical conditions, drug treatments), with potential confounding factors.

CONCLUSIONS

The present study confirms the association between male gender and violent suicide and suggests a correlation between obesity and the use of violent suicide methods. The relationship between obesity and suicidal behaviour is worthy of interest and deserves to be explored by further studies.

The role of seasonality and photoperiod on the lethality of suicide attempts: A case-control study

BACKGROUND

The risk factors related to suicidal behaviors are complex and not yet fully known. Several studies underline how suicide results from the combination of psycho-social, biological, cultural, and environmental factors. The aim of this study was to investigate the potential role of seasonality and photoperiod on high-lethality suicide attempts (HLSA) compared with low-lethality suicide attempts (LLSA) in a sample of psychiatric inpatients.

METHODS

After attempting suicide, subjects were admitted in the emergency/psychiatric ward of the IRCCS Ospedale Policlinico San Martino from 1st August 2013 to 31st July 2018. Socio-demographic and clinical characteristics were collected.

RESULTS

The sample consisted of four hundred thirty-two individuals admitted for suicide attempt. One hundred thirty-three subjects (30.8%) of the sample committed a HLSA. The HLSA group peaked in the months with a higher sunlight exposure (June and July). Bivariate correlation analyses between seasonality/photoperiod in the whole sample and HLSA were positively associated with summer and highest solar intensity period.

LIMITATIONS

Data were limited to a single hospital, patients' seasonal environment, meteorological variables and psychological factors. In addition, the presence of acute life-events fostering the suicidal crisis has not been investigated.

CONCLUSIONS

The current study provides a novel perspective on the questions surrounding the impact of seasonality and daylight exposure on lethality of suicide attempts. further studies are needed to provide deeper understandings on the delicate molecular network that links suicide behaviors, seasonality and daylight in order to develop more effective prevention and treatment strategies in the future.

Sleep and circadian rhythms as possible trait markers of suicide attempt in bipolar disorders: An actigraphy study

BACKGROUND

The poor prognostic of Bipolar disorders (BD) is closely linked to deaths by suicide. Sleep and circadian abnormalities are observed during all phases of BD and are also associated with suicide attempt (SA). In this context, this study sought to identify specific sleep and circadian rhythms markers associated with suicidal attempt in euthymic patients with BD.

METHODS

The sample (N = 236) comprised 3 groups: 147 patients with BD including 57 with a history of SA and 90 without (NoSA), and 89 healthy controls (HC). All participants were recorded during 21 days with actigraphy.

RESULTS

SA was associated with women gender (p = 0.03), familial history of SA (p = 0.03), mixed episodes (p = 0.001), and benzodiazepines (p = 0.019). SA, compared to noSA, had a morning phase preference (p = 0.04), and were more vigorous on the circadian type inventory (p = 0.04), and tended to suffer more from insomnia (45% versus 25% respectively, p = 0.10). SA was also associated with an earlier onset of daily activity assessed with actigraphy (M10 onset: p = 0.01). Backward stepwise linear regression indicated that a combination of four variables (Gender, vigour, insomnia, M10onset) significantly differentiated patients with SA from NoSA (p = 0.03).

LIMITATIONS

Cross-sectional design, and no examination of suicidal behaviors' subgroups such as first attempters or repeaters, or violent suicide attempt.

CONCLUSIONS

Woman gender, vigorous circadian type, insomnia and an earlier daily activity appeared independently associated with SA in BD. If these biomarkers are confirmed in prospective studies, they should be screened and used to prevent suicide, with the development of personal and targeted chronobiological treatments.

The Association Between Dyslipidemia and Lethality of Suicide Attempts: A Case-Control Study

Evidence supports the existence of an association between dyslipidemia, psychiatric disorders, and suicide risk due to the effects of altered lipid profiles on serotoninergic neuron membranes. The aim of this study was to investigate the differences in c-reactive protein (CRP), thyroid functioning, total cholesterol, high lipoprotein density cholesterol (HDL-c), low-lipoprotein density cholesterol (LDL-c), and triglycerides (TG) serum levels in low lethality (LLSA) vs. high lethality suicide attempters (HLSA) within 24 h from the suicide attempt and inpatients who never attempted suicide (NAS). After attempting suicide, subjects were admitted to the emergency ward of the IRCCS Ospedale Policlinico San Martino and later to the section of Psychiatry from 1st August 2013 to 31st July 2018. Socio-demographic and clinical characteristics, serum lipids profile, CRP, and thyroid functioning were collected. The sample consisted of 133 individuals with a HLSA, 299 subjects with LLSA, and 200 patients NAS. HLSA subjects were more likely to be males and diagnosed as having a bipolar disorder. Furthermore, HLSA subgroup showed significantly lower total cholesterol and LDL-c levels and higher CRP serum levels compared to LLSA and control group, respectively. LLSA subgroup showed higher HDL-c levels compared to HLSA subgroup (no differences between HLSA and control group were observed). Additionally, the control group reported higher triglycerides levels compared to patients admitted to psychiatric ward for a suicide attempt. Only male gender, having a diagnosis of bipolar disorder, lower total cholesterol, and higher CRP serum levels predicted HLSA. Investigating the relation between dyslipidemia and the severity of suicide attempts may contribute to reveal the complex determinants underlying at-risk behaviors such as suicide, thus playing a relevant role in the possible prevention of this disabling phenomenon.

Mean platelet volume and neutrophil to lymphocyte ratio as parameters to indicate the severity of suicide attempt

This study was designed to compare the complete blood count (CBC) values of 38 violent suicidal attempt (VSA) and 38 nonviolent suicidal attempt (NVSA) patients and 38 healthy controls, particularly mean platelet volume (MPV) and neutrophil to lymphocyte ratio (NLR). MPV was found to be significantly higher (P = 0.000), and PLT was found to be significantly lower in the VSA group (P = 0.001). NLR was found to be significantly higher (P = 0.005) in the VSA group. The area under the receiver operating characteristic curve of MPV levels for VSA was 0.78 and 0.68 for NLR in the VSA group when compared with the NVSA group.