Risk factors for suicidal ideation of the general population

Factors Related to Suicidal Ideation by Gender and Age Group in Korean Adults

BACKGROUND

According to the results of the age-standardized suicide rate (suicide deaths per 100,000 population) published by Organization for Economic Cooperation and Development countries from 2003 to 2019, the suicide rate in Korea is ranked first almost every year, so it should be managed at the national level. To reduce the suicide rate, many scholars are studying suicide. The suicidal process begins with suicidal ideation, progresses through suicide attempts, and ends with suicide. Among them, the frequency of suicidal thoughts was found to be highly correlated with suicide plans and attempts, and it is said that 60% of those who change from suicidal ideation to attempts appear within one year. Therefore, research related to suicidal ideation to lower the suicide rate will contribute to preventing suicide at an early stage.

METHODS

This study used data from the Korea National Health and Nutrition Examination Survey (KNHANES). Among them, data from 2013, 2015, 2017, and 2019 surveyed adults were compared for suicidal ideation among 18,339 adults. Considering the characteristics of the KNHANES data, complex sample analysis was performed considering the primary extraction unit (region), stratification variables, and weights. The Rao-Scott χ² test was stratified by age group to confirm the distribution of suicidal ideation according to general characteristics. Univariate and multiple logistic regression analyses were performed to understand the effect on suicidal ideation.

RESULTS

Among all subjects, the rate of suicidal ideation was 4.75%, and among the age groups, the rate of suicidal thoughts was the highest among those over 80 years old (10.39%). Compared to those who were 50s, those in their 30s had the lowest suicidal ideation (odds ratio [OR], 0.52; 95% confidence interval [CI], 0.39-0.70), and those in their 80s had the highest rate of suicidal ideation (OR, 1.97; 95% CI, 1.38-2.82). Except for those in their 20s, the rate of suicidal ideation tends to increase with age. Overall, the lower 25% of the Euro Quality of Life-5 Dimensions (EQ-5D) index, depression lasting more than two weeks, and subjects with poor subjective health or high stress were more likely to have suicidal ideation. In particular, EQ-5D Index (OR, 5.86; 95% CI, 3.73-9.20), depressive symptoms (OR, 19.65; 95% CI, 9.94-38.83) in 20s, and stress in 80s (OR, 10.87; 95% CI, 5.63-20.96) was the highest, and those had the good subjective health perception in 30s (OR, 0.10; 95% CI, 0.05-0.20) was lowest. Participants in their 30s, 40s, and 60s who were divorced or widowed and those in their 50s and 60s who had never married or lived together were more likely to consider suicide ideation. Except for those in their 20s and 80s, the rate of suicidal ideation tends to increase with lower household income levels.

CONCLUSIONS

In the results of this study, it can be seen that a combination of factors such as a person's personality traits, stress or coping ability to various events, social support, and mental or physical limitations influence suicidal behavior. Suicidal ideation is not simply affected by a single factor but may be influenced by multiple factors.

The Mediating Role of Tolerance for Psychological Pain in the Relationship Between Different Types of Childhood Traumatic Experiences and Suicidal Ideation

The aim of the present research was to evaluate the mediating effects of facets of the tolerance for psychological pain on the relationship between childhood trauma and suicidal ideation. A sample of 437 community individuals and a sample of 316 college students participated. For the community sample, managing the pain mediated the relationship between childhood trauma, the different types of traumatic experiences and suicidal ideation. In the college sample, managing the pain and enduring the pain mediated the relationship between childhood trauma, the different types of traumatic experiences and suicidal ideation, except for the case of sexual abuse. The present results have potential clinical implications. Mental health professionals should be aware of the long-term consequences of exposure to childhood trauma and need to assess the ability to tolerate psychological pain so as to implement appropriate psychological interventions that help individuals cope with their pain.

Increased Levels of Cortisol in Individuals With Suicide Attempt and Its Relation With the Number of Suicide Attempts and Depression

BACKGROUND

Abnormalities in the hypothalamic-pituitary-adrenal axis (HPA) have been reported in individuals with suicide behavior. The aim of the study was to evaluate cortisol levels in peripheral plasma of individuals with more than one suicide attempt.

METHODS

Cortisol concentrations in peripheral plasma were measured using the ELISA technique. Suicide attempts were evaluated by the Columbia Suicide Severity Rating Scale, while depression was evaluated by the Hamilton Depression Rating Scale.

RESULTS

We found elevated cortisol levels in the suicide attempt group when compared with healthy controls (F = 7.26, p-value = 0.008), but no statistical differences with the psychiatric diseases group (F = 1.49, p-value = 0.22). Cortisol levels were higher in individuals with depression (F = 8.99, P = 0.004) and in individuals with two or more suicide attempts (F = 13.56, P < 0.001).

CONCLUSIONS

Cortisol levels are increased in individuals who attempt suicide and higher of cortisol concentrations in plasma regard to depression and more attempts of suicide.

Development of Autonomic Nervous System Assays as Point-of-Care Tests to Supplement Clinical Judgment in Risk Assessment for Suicidal Behavior: A Review

PURPOSE OF REVIEW

A biomarker point-of-care (POC) test that supplements the psychiatric interview and improves detection of patients at risk for suicide would be of value, and assays of autonomic nervous system (ANS) activity would satisfy the logistical requirements for a POC test. We performed a selective review of the available literature of ANS assays related to risk for suicide.

RECENT FINDINGS

We searched PubMed and Web of Science with the strategy: "suicide OR suicidal" AND "electrodermal OR heart rate variability OR pupillometry OR pupillography." The search produced 119 items, 21 of which provided original data regarding ANS methods and suicide. These 21 studies included 6 for electrodermal activity, 14 for heart rate variability, and 1 for the pupillary light reflex. The 21 papers showed associations between ANS assays and suicide risk in a direction suggesting underlying hyperarousal in patients at risk for suicide. ANS assays show promise for future development as POC tests to supplement clinical decision making in estimating risk for suicide.

A network analysis of suicidal ideation, depressive symptoms, and subjective well-being in a community population

Although the relationship between subjective well-being (SWB) and suicidal ideation (SI) has been illustrated in previous research, few studies have conceptualized SWB as a comprehensive measure of life satisfaction in multiple domains, nor have they considered possible mediators such as depressive symptoms. Therefore, the present study aimed to identify dimensions of SWB correlated with SI, and to analyze associations among SWB sub-domains, depressive symptoms, and SI in a community population. A total of 1200 community adults in South Korea, aged 20-86 years, completed self-report questionnaires on demographics, depressive mood (Patient Health Questionnaire-9 [PHQ-9]), SI (item 9 of the PHQ-9), and 14 SWB sub-domains (Subjective Well-Being Inventory). Factors associated with SI, and interactions among SI, depressive mood, and SWB, were identified by logistic regression and phenotype network analyses, respectively. The five main factors influencing the regularized partial correlation network were life satisfaction, self-blame, job, hopelessness, and fatigue. Pathways were observed from work-life balance and life satisfaction to hopelessness; from self-blame and fatigue to safety and health; and from sleep disturbance, concentration difficulties, self-blame, and hopelessness to SI. Making job activities more emotionally rewarding, the potential for career progression and regular work hours could address anhedonia, hopelessness and sleep disturbance, respectively, thus enhancing SWB and reducing SI in the community population.

Suicidal Ideation Mediates the Relationship Between Affect and Suicide Attempt in Adolescents

Suicide, as one of the leading causes of death for the adolescent population, both in Chile and globally, remains a complex and elusive phenomenon. This research studies the association between positive and negative affect in relation with suicidal ideation and suicidal attempt, given that affectivity is a fundamental basis on which people make evaluations on their satisfaction with life. First, it examines the reliability, structure, and validity of Watson's positive and negative affect scale (PANAS) scale in a representative random sample of Chilean high school students (N = 4,568). The scale evidences strong reliability coefficients and a confirmatory factor analysis, excluding one positive (excited) and one negative (nervous) item. The scale shows a satisfactory goodness of fit. Secondly, it investigates the association of PANAS positive and negative affect scores with suicidal ideation as well as reported attempt in adolescents, controlling for the potential effect of age and sex (N = 420 high school students). Low positive and high negative affect, but not sex and age, show a significant association with suicidal ideation. Suicidal ideation totally mediates the association of affect with suicide attempt, as expected. Results are discussed regarding prevention and it considers how positive and negative affect can be relevant as indicators for prevention and treatment using widely available technology.

Exploring the psychiatric and social risk factors contributing to suicidal behaviors in religious young adults

The religion-suicide relationship is complex, and evidence of the role of religion in suicidal behaviors is inconsistent. This cross-sectional study aims to explore suicidal ideation and attempts among Modern Orthodox Jews and to examine the risk factors for suicidality in the presence of religious practice and affiliation, help-seeking behaviors, and social support. 321 young adults aged 18 to 36 completed self-report questionnaires assessing religious commitment and perception of religion as important, suicidal risk, depression, somatic symptoms, alcohol misuse, social support, and help-seeking patterns. The past 12-month suicide ideation prevalence was 8.7%. 14% of the sample were at risk for suicide. Those at a higher risk for suicide were less involved in religious practices and perceived religion as less important. In addition, depressive symptoms and alcohol misuse at a younger age presented the highest correlation with suicidal risk. The high rate of suicidal ideation among Modern Orthodox young adults highlights their vulnerability in the face of a lack of social support and mental health resources. Due to the limitations inherent in a convenience sampling, i.e., limited generalizability, this study may represent an underestimation of a risk for suicide amongst Modern Orthodox adults.

Insomnia Is Associated With Frequency of Suicidal Ideation Independent of Depression: A Replication and Extension of Findings From the National Health and Nutrition Examination Survey

OBJECTIVE

Insomnia is associated with suicidality, although the mechanisms of this association are unclear. This study sought to replicate previous findings showing that insomnia symptoms but not sleep duration are associated with frequency of suicidal ideation in adults. We further investigated whether depression or sleep duration moderates the association between insomnia symptoms and frequency of suicidal ideation.

MATERIALS AND METHODS

We used the 2005-2006 cycle of the National Health and Nutrition Examination Survey to replicate previously reported findings from the 2007-2008 cycle. We used ordered logistic regression to determine whether insomnia symptoms were associated with frequency of suicidal ideation independently of depression and other potential confounds. To extend these findings, we tested whether depression or sleep duration moderated the association between insomnia symptoms and frequency of suicidal ideation. We further replicated these findings in parallel analyses using the combined data from the 2005-2006 and 2007-2008 cycles.

RESULTS

This study replicated previous results showing that insomnia symptoms are associated with frequency of suicidal ideation in the NHANES 2005-2006 cycle (OR = 1.09, p < 0.05), even after adjusting for potentially confounding variables, including depression. Neither depression nor sleep duration moderated this association. Difficulty with sleep maintenance insomnia symptoms were most robustly associated with frequency of suicidal ideation (OR ≥ 1.97, p < 0.05). Sleep duration was not robustly associated with suicidal ideation.

CONCLUSIONS

In this study, we found that insomnia symptoms were uniquely associated with frequency of suicidal ideation. This association cannot be explained by the shared association with depression or sleep duration.

Predicting Suicide Ideation in the Military: The Independent Role of Aggression

The purpose of this study was to examine the longitudinal relationship between aggression and suicide ideation when controlling for other externalizing (i.e., alcohol misuse and risk-taking) and internalizing (i.e., depression and sleep problems) risk factors in an active duty, military sample. Preexisting data from a longitudinal study were analyzed to assess the wellness of service members across the deployment cycle. Participants were 944 active duty service members (95% male, 48% between 18 and 24 years old) who completed surveys upon initial return from deployment and approximately 3 months later. After controlling for other externalizing (alcohol misuse, risk-taking) and internalizing (depression, sleep problems) risk factors, service members reporting aggression were significantly more likely to report suicide ideation than those reporting no aggression (OR = 3.19; OR 95% CI: 1.16-8.80). The independent nature of the relationship between anger and suicidality suggests aggression may be an important indicator of suicidality for service members. Understanding the role of aggression in suicidality may improve the ability to identify at-risk service members and to develop effective interventions to reduce suicide risk.

Is suicidal ideation associated with allergic asthma and allergic rhinitis?

Objective:

To investigate whether there is an association between suicidal ideation (SI) and allergic diseases in adults.

Methods:

This was a comparative cross-sectional study involving individuals ranging from 20 to 50 years of age recruited from a university hospital in the city of Guadalajara, Mexico. We included patients with a confirmed diagnosis of allergic asthma, those with a confirmed diagnosis of allergic rhinitis, and healthy controls. All subjects completed the Beck Depression Inventory-II (BDI-II), which includes an item that evaluates the presence of suicidal thoughts or desires within the last two weeks, in order to identify SI.

Results:

The sample comprised 115 patients with allergic asthma, 111 patients with allergic rhinitis, and 96 healthy controls. The number of individuals identified with SI in the three groups were, respectively, 17 (14.8%), 13 (11.7%), and 8 (8.3%). Regarding the presence of SI, no statistically significant association was found in the allergic asthma group (OR = 1.98; 95% CI: 0.78-4.64; p = 0.154) or in the allergic rhinitis group (OR = 1.46; 95% CI: 0.58-3.68; p = 0.424) when they were compared with the control group. However, the presence of depression was associated with SI in the three groups: allergic asthma (OR = 12.36; 95% CI: 2.67-57.15; p = 0.001); allergic rhinitis (OR = 6.20; 95% CI: 1.66-23.14; p = 0.006); and control (OR = 21.0; 95% CI: 3.75-117.36; p < 0,001).

Conclusions:

In comparison with the control group, no association was found between SI and the groups with allergic diseases. In contrast, there was association between SI and depression in the three groups.

Relative handgrip strength in relation to depressive mood and suicidal ideation in Koreans using the 2015 KNHANES data

OBJECTIVES

This study aimed to examine the association of relative handgrip strength (RHGS) with depressive mood and suicidal ideation.

METHODS

A cross-sectional study was conducted among 2167 men and 2643 women (aged 50.9 years ± 16.7 years) who participated in the 2015 Korean National Health and Nutrition Examination Survey. RHGS was defined by the handgrip strength/body mass index (BMI) ratio. Depressive mood and suicidal ideation were assessed using self-reported questionnaires. Logistic regression analysis was conducted after adjusting for sex, concurrent illness, age, education, income, smoking status, alcohol use, physical activity, and depressive mood (in the analysis for suicidal ideation).

RESULTS

Among participants, 4.0% men and 5.7% women reported serious suicidal ideation while 9.5% men and 16.0% women reported serious depressive mood. After adjusting for confounding factors, RHGS was associated with depressive mood (odds ratio [95% confidence interval] per RHGS [kg/BMI], 0.82 [0.69-0.99]) and suicidal ideation (0.73 [0.54-0.99]). In sex-specific relationship, RHGS was associated with depressive mood and suicidal ideation in women (0.71 [0.55-0.93] and 0.54 [0.34-0.85], respectively) but not in men.

CONCLUSIONS

Poorer RHGS indicates higher risk of depressive mood as well as suicidal ideation regardless of depressive mood among women.

Correlates of depressive symptoms in late middle-aged Taiwanese women: findings from the 2009 Taiwan National Health Interview Survey

Background

Previous studies have shown that depressive symptoms in middle-aged women were associated with a number of factors such as climacteric symptoms. Nevertheless, studies based on population-based data with a wide range of potential correlates are still scarce. Therefore, the aim of this study was to investigate the correlates of depressive symptoms in late middle-aged Taiwanese women using data from a nationally-representative, population-based survey.

Methods

Women aged 50.0–65.0 years were identified from the dataset of the 2009 Taiwan National Health Interview Survey. The outcome measure was depressive symptoms in the past week, evaluated using the Center for Epidemiologic Studies Short Depression Scale (CES-D 10) with a cut-off score of 10 or greater. Univariate and multiple logistic regression analyses were used to evaluate the correlates of depressive symptoms.

Results

The mean age of the 533 respondents was 56.7 years. Depressive symptoms were present in 53 respondents (9.9%). Multiple logistic regression analysis revealed that an education level of elementary school or below (adjusted odds ratio [AOR] = 3.19, P = 0.003), nulliparity (AOR = 8.10, P = 0.001), living alone (AOR = 5.47, P = 0.003), never having worked (AOR = 4.14, P = 0.008), lack of regular exercise (AOR = 3.01, P = 0.003), a perceived health status of fair or bad (AOR = 4.34, P < 0.001), and somatic climacteric symptoms (AOR = 2.32, P = 0.012) were independent and significant factors of depressive symptoms in late middle-aged Taiwanese women.

Conclusions

Findings from this secondary analysis of a population-based survey suggested independent associations of somatic climacteric symptoms, and a number of socio-demographic and health-related factors with depressive symptoms in late middle-aged Taiwanese women.

Factors Associated with Perceived Depression of Korean Adults: Secondary Data from the Korean Community Health Survey

This study was aimed to identify factors related with Korean adults' depression in a community population using secondary data from the Korean Community Health Survey. The results showed factors associated with the Korean adults' perceived depression were subjective health, alcohol drinking, smoking, hypertension, diabetes mellitus, hours of sleep, activity impairments, and stress. Result of this study proposes that community mental health services are required to the population who has problems of activity impairment due to acute or chronic health status, which suggests having mental health problems such as alcohol drinking, smoking, depression, or stress.

Gender-Specific Factors Associated with Suicide Attempts among the Community-Dwelling General Population with Suicidal Ideation: the 2013 Korean Community Health Survey

We identified traditional risk factors and investigated poorly understood risk factors for suicide attempts according to gender in a large Korean population. We analyzed the data from 6,768 males and 12,475 females with suicidal ideation obtained from the nationwide 2013 Korean Community Health Survey. The dependent variable was suicide attempts within the past year. There was a significant trend towards an increase in suicide attempts with decreasing age in both genders. Compared with those who were married, suicide attempts were significantly higher among those who were widowed, divorced, or separated for males (odds ratio [OR], 2.07; 95% confidence interval [CI], 1.34-3.20), but lower for females (OR, 0.66; 95% CI, 0.45-0.98). Current smoking and depression were significant risk factor for suicide attempts in males and females. However, monthly household income, myocardial infarction, and osteoporosis were significantly associated with suicide attempts only in males, whereas education level, recipient of National Basic Livelihood Security, family contact, leisure activity, and drinking frequency were significantly associated only in females. These findings indicate that gender difference should be considered in the assessment, prevention, and management of future suicide attempts by community policy-makers and clinicians.

Decreased regional gray matter volume in suicide attempters compared to suicide non-attempters with major depressive disorders

OBJECTIVE

This study investigated regional gray matter (GM) volume differences between suicide attempters and suicide non-attempters with major depressive disorder (MDD) and their relationship with psychological risk factors for suicidality.

METHODS

MDD patients with and without a suicide attempt history (n=19 in each group) participated. The Hamilton Depression Rating Scale, Clinical Global Impression (severity subscale), Scale for Suicide Ideation (SSI), Risk-Rescue Rating (RRR), Beck Hopelessness Scale (BHS), Barrett Impulsivity Scale, Eysenck Personality Questionnaire, and Ways of Coping Checklist (WCCL) were administered. T1-weighted structural magnetic resonance imaging scans were acquired to evaluate changes in GM volume. Voxel-based morphometry was performed using the SPM 8 software package. Two-sample t-tests were used during second-level group comparison analysis; partial correlation analysis controlling for gender and age identified associations between regional GM volume and psychological measures.

RESULTS

Suicide attempters exhibited significantly decreased GM volume in the left angular gyrus (p<0.001, uncorrected) and right cerebellum (p<0.001, uncorrected). GM volume in the left angular gyrus was inversely correlated with BHS scores (r=-0.55, p<0.01) and positively correlated with the Seeking Social Support subscale of the WCCL (r=0.43, p<0.01).

CONCLUSION

These findings provide evidence of a neural basis of suicidal behaviors in MDD. In particular, reduced GM volume in the left angular gyrus may be a neurobiological marker of suicidality in depressed patients.

Body Composition, Sarcopenia, and Suicidal Ideation in Elderly Koreans: Hallym Aging Study

This study was conducted to assess the relationship between body composition and suicidal ideation among the Korean elderly population (n = 302; ≥ 65 years) who participated in the Hallym Aging Study in 2010. Body composition was measured using dual-energy X-ray absorptiometry, and obesity was measured by the indices of body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), and body fat percentage. Sarcopenia was defined as presence of both low muscle mass and low muscle function. Suicidal ideation was assessed using the Beck Scale for Suicide Ideation. We found no differences in body composition measures between subjects with suicidal ideation and those without. In the logistic regression analyses, there were no significant relationships for suicidal ideation according to body composition measures, including BMI, WC, WHR, WHtR, and body fat percentage in both sexes. After adjusting for age, smoking status, alcohol drinking, regular exercise, medical comorbidities, monthly income, education level, and presence of depressive symptoms, the odds ratio (OR) of suicidal ideation was higher in elderly men with sarcopenia compared to those without, whereas no significant relationships were observed in elderly women (OR 8.28, 95% confidence interval [CI] 1.20-61.34 in men; OR 0.79, 95% CI 0.07-8.43 in women). Sarcopenia is closely associated with an increased risk of suicidal ideation in elderly men.

Determinants of Mental Health Care Utilization in a Suicide High-risk Group With Suicidal Ideation

Objectives:

The suicide rate in Korea is increasing every year, and is the highest among the Organization for Economic Cooperation and Development countries. Psychiatric patients in particular have a higher risk of suicide than other patients. This study was performed to evaluate determinants of mental health care utilization among individuals at high risk for suicide.

Methods:

Korea Health Panel data from 2009 to 2011 were used. Subjects were individuals at high risk of suicide who had suicidal ideation, a past history of psychiatric illness, or had utilized outpatient services for a psychiatric disorder associated with suicidal ideation within the past year. The chi-square test and hierarchical logistic regression were used to identify significant determinants of mental health care utilization.

Results:

The total number of subjects with complete data on the variables in our model was 989. Individuals suffering from three or more chronic diseases used mental health care more frequently. Mental health care utilization was higher in subjects who had middle or high levels of educational attainment, were receiving Medical Aid, or had a large family size.

Conclusions:

It is important to control risk factors in high-risk groups as part of suicide prevention strategies. The clinical approach, which includes community-based intervention, entails the management of reduction of suicidal risk. Our study identified demographic characteristics that have a significant impact on mental health care utilization and should be considered in the development of suicide prevention strategies. Further studies should examine the effect of mental health care utilization on reducing suicidal ideation.

Joint Consensus Statement of the American Academy of Sleep Medicine and Sleep Research Society on the Recommended Amount of Sleep for a Healthy Adult: Methodology and Discussion

The American Academy of Sleep Medicine and Sleep Research Society recently released a Consensus Statement regarding the recommended amount of sleep to promote optimal health in adults. This paper describes the methodology, background literature, voting process, and voting results for the consensus statement. In addition, we address important assumptions and challenges encountered during the consensus process. Finally, we outline future directions that will advance our understanding of sleep need and place sleep duration in the broader context of sleep health.

Joint Consensus Statement of the American Academy of Sleep Medicine and Sleep Research Society on the Recommended Amount of Sleep for a Healthy Adult: Methodology and Discussion

The American Academy of Sleep Medicine and Sleep Research Society recently released a Consensus Statement regarding the recommended amount of sleep to promote optimal health in adults. This paper describes the methodology, background literature, voting process, and voting results for the consensus statement. In addition, we address important assumptions and challenges encountered during the consensus process. Finally, we outline future directions that will advance our understanding of sleep need and place sleep duration in the broader context of sleep health.

The Effect of Sleep Problems on Suicidal Risk among Young Adults in the Presence of Depressive Symptoms and Cognitive Processes

We aimed to investigate the effect of sleep problems, depression, and cognitive processes on suicidal risk among 460 young adults. They completed self-report questionnaires assessing suicidal behavior, sleep quality, depressive symptoms, emotion regulation, rumination, and impulsivity. Suicidal participants exhibited higher rates of depressive symptoms, sleep problems, expressive suppression, rumination, and impulsivity. A confirmatory factor analysis model revealed pathways to suicidal risk that showed no direct pathways between sleep problems and suicidal risk. Instead, sleep was related to suicidal risk via depression and rumination, which in turn increased suicidal risk. These results suggest that addressing sleep problems will be useful in either the treatment or prevention of depressive and rumination symptoms and reduction in suicidal risk.

Suicidal ideation and distress in family members bereaved by suicide in Portugal

The present study assessed the impact of suicide and distress on suicidal ideation in a sample of 93 Portuguese family members bereaved by suicide. A control community sample of 102 adults also participated. After controlling for educational level, those bereaved by the suicide of a family member were found to have higher levels of suicidal ideation. Forty-two percent of family members had Suicide Ideation Questionnaire scores at or above the cutoff point. General distress, depression, anxiety, and hostility related to suicidal ideation, whereas time since suicide also interacted with general distress and depression in predicting suicidal ideation.

Suicidal ideation and occupational pesticide exposure among male farmers

BACKGROUND

The occupation of farming has been reported to be associated with a high suicide rate, and suicidal ideation is an important risk factor for suicide. The objective of this study was to explore the association between occupational pesticide exposure or poisoning history and suicidal ideation among male farmers in South Korea.

METHODS

Through a nationwide sampling survey, a total of 1958 male farmers were interviewed in 2011 in South Korea. Detailed occupational pesticide exposure and pesticide poisoning information were obtained from face-to-face interviews. Suicidal ideation was defined as whether they had thought of harming themselves or trying to take their own lives over the preceding year. Logistic regression analyses were conducted to examine the effect of pesticide poisoning on suicidal ideation.

RESULTS

Among all farmers, 4.7% (n=92) reported suicidal ideation in 2010. After controlling for potential confounders, lifetime hospitalization due to pesticide poisoning showed a 2.48-fold increase in risk (95% CI: 1.26, 4.91). Those with multiple poisonings showed more significant associations with suicidal ideation (OR=2.33 for once, OR=3.02 for more than once). Moderate- or severe-symptom severity of acute pesticide poisoning cases (OR=2.23; 95% CI: 1.21-4.11) also showed increased risks of suicidal ideation than the milder classes did. However, no significant association was identified with cumulative lifetime pesticide application and suicidal ideation.

CONCLUSIONS

Our findings suggest that risk of suicidal ideation is related to occupational pesticide poisoning among male farmers.

Relationship between current sleep duration and past suicidal ideation or attempt among Korean adolescents

Objectives

To comprehensively examine the relationship between current sleep duration and past suicidal idea or attempt among Korean adolescents.

Methods

Data came from the 2009 Korea Youth Risk Behavior Web-based Survey with 75 066 participants (with the participation rate of 97.6%) in 800 middle and high schools. Binary logistic regression was conducted by gender and depressed mood to identify significant factors for suicidal ideation/attempt. The dependent variable was the log odds of suicidal ideation/attempt, while the independent/control variables were sleep duration and other demographic, socio-economic and health-related factors.

Results

A negative association between sleep duration and suicidal ideation or attempt was weaker for those with depressed mood than for those without such experience in Korea for Year 2009. The odds ratio of suicidal ideation/attempt regarding less than 4 hours of sleep compared to 6 to 7 hours of sleep, was smaller in a group with depressed mood than in a group without such experience, for example, 1.64 (95% confidence interval [CI], 1.29 to 2.08) vs. 2.06 (95% CI, 1.34 to 3.17) for men's suicidal ideation, 2.50 (95% CI, 1.69 to 3.69) vs. 3.89 (95% CI, 1.74 to 8.66) for men's suicidal attempt. A negative association between age (or self-rated health) and suicidal ideation/attempt was also weaker for those with depressed mood than for those without such experience in the nation for the year.

Conclusions

There was a negative association between sleep duration and suicidal ideation/attempt in Korea for Year 2009 and this association was weaker for those with depressed mood than for those without such experience. Based on the findings of this study, adolescents' better mental health and longer, more comfortable sleep might help to prevent their suicidal ideation and attempt in Korea.

The link between suicide and insomnia: theoretical mechanisms

Insomnia has been established as a risk factor for depression and mental illness for decades, but a growing body of evidence has recently exposed insomnia to be an independent risk factor for suicide that encompasses all age ranges. This discovery has invigorated investigation to elucidate the relationship between insomnia and suicide, and over 20 studies reinforcing this association in adults have been published since 2010 alone. This article analyzes relevant research and emphasizes studies published within the last three years with the intent of proposing theoretical mechanisms explaining the link between suicide and insomnia. These mechanisms may then be used as targets for future investigation of treatment.