Experience of using the molecular genetic studies to assess the risk of suicide

In the recent decades, there has been widespread the opinion that genetic markers of the suicidal behavior (suicide, suicidal attempts, suicidal thoughts) can be used to predict the suicidal behavior.The purpose of the study was to determine the possibility of using the method of molecular genetic research to assess the risk of suicide in men of 18‒27 years.The study used the case-control method. The control group included 100 men of 18‒27 years who never had mental disorders. The suicide group included the persons who committed highly traumatic methods of self-harm and were motivated to commit suicide (30 persons). DNA isolation was performed using a NucleoSpin Blood kit (Macherey‒Nagel, Germany) according to the manufacturer’s protocol. Each DNA sample was analyzed for polymorphism by allelic discrimination using the real-time polymerase chain reaction (PCR).The frequencies of occurrence of genotypes and alleles of the following genes were analyzed: HTR1A, rs6295 (G/C); BDNF, rs6265 (G/A); COMT, rs4680 (G/A); SKA2, rs7208505 (C/T); SLC6A4 (5HTT), rs25531 (T/C); 5HTR2A, rs6313 (G/A); TPH2, rs4570625 (G/T); TPH1, rs1800532 (G/T).A statistically significant difference was found for the frequency of occurrence of genotypes and alleles of the rs25531 polymorphism of the SLC6A4 (5HTT) gene. The chance of being in the suicide group with a heterozygous genotype (T/C) carriage was 2.346 times higher.The significance of the rs25531 polymorphism of the SLC6A4 (5HTT) gene for the formation of the suicidal behavior was confirmed.

Development of a Suicide Prediction Model for the Elderly Using Health Screening Data

Suicide poses a serious problem globally, especially among the elderly population. To tackle the issue, this study aimed to develop a model for predicting suicide by using machine learning based on the elderly population. To obtain a large sample, the study used the big data health screening cohort provided by the National Health Insurance Sharing Service. By applying a machine learning technique, a predictive model that comprehensively utilized various factors was developed to select the elderly aged > 65 years at risk of suicide. A total of 48,047 subjects were included in the analysis. Individuals who died by suicide were older, and the number of men was significantly greater. The suicide group had a more prominent history of depression, with the use of medicaments significantly higher. Specifically, the prescription of benzodiazepines alone was associated with a high suicide risk. Furthermore, body mass index, waist circumference, total cholesterol, and low-density lipoprotein level were lower in the suicide group. We developed a model for predicting suicide by using machine learning based on the elderly population. This suicide prediction model can satisfy the performance to some extent by employing only the medical service usage behavior without subjective reports.

Let’s Live Healthier: The Relationship between Suicidal Behavior and Physical Activity in an Age-, Gender-, and Body Mass Index-Matched Adults

The purpose of this study was to identify the association between physical activity (PA) and predictors of suicidal behaviors and to investigate whether the different PA measurements influence the association between PA and suicidal behaviors in South Korean adults. This study analyzed data from the National Health and Nutrition Examination Survey 2014–2015 data. The study selected participants who checked suicide-related questions as “Yes” (n = 99) and checked suicide-related questions as “No” (n = 99) in the questionnaire. The age, gender, and body mass index of participants between the two groups were matched. The moderate to vigorous PA (p = 0.000) and sedentary PA (p = 0.000), measured by accelerometers, were a significant risk factor for suicidal behaviors. Furthermore, the number of steps was a considerable difference between the two groups (healthy group: 61,495.76 steps; suicide group: 40,517.34 steps), and the accelerometer and questionnaire also showed significant differences. The study demonstrated that there were significant associations with physical activity and socioeconomic status and suicidal behaviors in anthropometry (i.e., age, gender, height, weight) matched groups. Additionally, this study highlights the importance of the assessment of PAs, and increasing PA levels could reduce the incidence of suicidal behaviors.

Suicide amongst the Inuit of Nunavut: An Exploration of Life Trajectories

This article reports results of the life trajectories from 92 Inuit who died by suicide, matched for age and gender with 92 living-controls. A proxy-based procedure and semi-structured interviews with informants were conducted to obtain trajectories of developmental events occurring over the life course for suicide and community-matched controls. Results from this research indicate two different trajectories that differentiate the control-group from the suicide-group throughout the life course. Even though the number of suicide attempts are similar between both groups, the suicide-group had a more important burden of adversity, which seemed to create a cascading effect, leading to suicide.

Distinguishing suicides of people reported missing from those not reported missing: retrospective Scottish cohort study

BackgroundUnderstanding what distinguishes the suicide of individuals reported missing (missing-suicides) from those of individuals not reported missing (other-suicides) may have preventative and/or operational utility and inform our knowledge of suicide.AimsTo assess whether specific epidemiological, sociodemographic or circumstantial characteristics differ between individuals reported missing and those not reported missing who take their own life.MethodContent analysis of Scottish Police Death Reports, detailing 160 suicides/undetermined deaths over a 3-year period in the North-East of Scotland.ResultsThose in the missing-suicide group were more likely to be older but did not differ from the other-suicide group on any other epidemiological or sociodemographic characteristics. Individuals in the other-suicide group were more likely to be found inadvertently by people known to them. The missing-suicide group took longer to find and were more likely to be located in natural outdoor locations by police/searchers or members of the public.ConclusionsIndividuals who die by suicide and who are reported as a missing person differ from those not reported as missing in terms of factors relating to location and how they are found but not epidemiological or sociodemographic characteristics.Declaration of interestNone.

Evaluation of human pineal gland acetylserotonin O-methyltransferase immunoreactivity in suicide: A preliminary study

Disorders of the serotonergic system are especially known to be present in the neurobiology of suicidal behavior. Studies investigating melatonin levels show that changes in pineal gland functions may also play a role in the pathogenesis of suicide. However, to our knowledge, there are no studies evaluating the activity of pinealocytes responsible for melatonin synthesis in suicide. This preliminary study aimed to investigate the relationship among pinealocyte, acetylserotonin O-methyltransferase (ASMT) immunoreactivity, and suicide. Samples of pineal gland, cerebrospinal fluid, blood, and urine were obtained from 21 suicide and 21 non-suicide cases on which medicolegal autopsies were performed. Expression of ASMT in human pineal gland was evaluated by immunohistochemical methods. A scoring system was used to define the anti-ASMT-positive staining in the sections. Enzyme-linked immunosorbent assays were employed to assess serum and cerebrospinal fluid melatonin levels and blood and urine noradrenaline levels. The ASMT-immunopositive pinealocyte count was observed to be lower in suicide cases compared to the non-suicide cases. With the exception of two cases (with moderate staining), all graded scores were 3 (strong staining) in non-suicide group, whereas scores were 1 (mild staining) or 2 (moderate staining) in the suicide group. Melatonin levels in the blood were lower among the suicide victims. These results support decreased pineal gland activity in suicide. However, further studies are needed to assess whether these changes are related to a psychiatric disorder.

Suicide and body mass index

IntroductionIt has been suggested that there is a relationship between BMI and suicide. Thus, BMI of subjects who commit suicide would be lower than the BMI of other unnatural deaths (Flaig 2013).ObjectivesExplore the possible relationship between BMI and suicide.Material and methodsA total of 1197 suicides and 473 unnatural deaths (not by suicide) were collected systematically for 60 months at the Institute of Legal Medicine of Seville. Age, sex, weight, height and cause of death were recorded. Statistical analysis was performed using SPSS v19.0.Results(Figure 1)DiscussionIn our study we found that suicide (of all age groups and both sexes) have a lower BMI than controls. However, the relationship between these two variables is complex and not all studies support it. Moreover, the relationships between depression, suicide and overweight point in different directions. More and more studies indicate the existence of a relationship between depression and overweight, suggesting that perhaps the “epidemic” of depression and overweight that we see in Western societies has some connection. In addition, depression is a risk factor for suicide well established. Our results indicate that suicide group tends to have lower BMI (less weight in relation to its size) than the controls.Disclosure of interestThe authors have not supplied their declaration of competing interest.