Suicide and exposure to organophosphate insecticides: Cause or effect?

BACKGROUND: Suicide using pesticides as agent is recognized as a major cause of pesticide poisoning. METHODS: A literature review of mortality and morbidity studies related to suicide among pesticide-exposed populations, and of human and animal studies of central nervous system toxicity related to organophosphate (OP) pesticides was performed. RESULTS: Suicide rates are high in farming populations. Animal studies link OP exposure to serotonin disturbances in the central nervous system, which are implicated in depression and suicide in humans. Epidemiological studies conclude that acute and chronic OP exposure is associated with affective disorders. Case series and ecological studies also support a causal association between OP use and suicide. CONCLUSIONS: OPs are not only agents for suicide. They may be part of the causal pathway. Emphasizing OPs solely as agents for suicide shifts responsibility for prevention to the individual, reducing corporate responsibility and limiting policy options available for control.     

广东省居民自杀未遂的流行特征及影响因素分析

目的 了解广东省居民自杀未遂的注行特征,探讨自杀未遂的影响因素.方法 通过分层随机抽样抽取广东省21个县区中街道/乡镇的家庭为调查样本户,对每个住户用KISH法确定1名15～69岁的家庭成员进行问卷调查,获得自杀未遂及相关的危险因素.采用SPSS 16.0软件对数据进行分析,筛选自杀未遂的危险凶素.结果 共调查6625人,过去一年内自杀未遂的发生率为0.8%,其中女性(1.1%)高于男性(0.5%),25～35岁女性自杀未遂率最高(1.6%),城市农村间差异无统计学意义.多因素分析显示,女性(OR=2.1)、经历负性事件(OR=15.5)、睡眠状况差(OR=1.6)、孤独感(OR=1.5)、焦虑感(OR=1.8)是自杀未遂的危险因素;而饮酒、吸烟、体力活动情况、文化程度、年龄、城乡、家庭农药存放情况与自杀未遂发生无显著相关.结论 广东省自杀未遂发生率高,影响因素复杂,应该采取综合的措施进行预防控制.     

A Longitudinal Study of Predictors of Suicide Attempts Among Lesbian, Gay, Bisexual, and Transgender Youth

This short-term prospective study examined general and lesbian, gay, bisexual, and transgender (LGBT)-specific risk and protective factors for suicide attempts in an ethnically diverse sample of LGBT youth (N = 237, 47.7 % male). A structured psychiatric interview assessed clinical depression and conduct disorder symptoms, as well as past and prospective suicide attempts over a 1-year follow-up period (91 % retention). Participants completed questionnaires measuring general risk factors for suicide attempts, including hopelessness, impulsiveness, and perceived social support. They also completed measures of LGBT-specific suicide risk factors, including gender nonconformity, age of first same-sex attraction, and LGBT victimization. Correlation and multivariate regression analyses were conducted to examine the relations between predictors and suicide attempt, and to identify mediators. Of nine variables examined, seven were related to lifetime history of attempted suicide: hopelessness, depression symptoms, conduct disorder symptoms, impulsivity, victimization, age of first same-sex attraction, and low family support. Depressive symptoms and hopelessness mediated the relation between multiple risk and resilience factors and suicide attempts. Suicide attempt history was the strongest predictor of prospective suicide attempts. Participants who previously attempted suicide (31.6 % of the sample) had more than 10 times greater odds of making another attempt in the 1-year follow-up period than were those who had made no previous attempt. These results highlight the need for suicide prevention programs for LGBT youth and suggest the importance of addressing depression and hopelessness as proximal determinants and family support and victimization, which have more distal effects.     

Community-based suicide prevention program in Japan using a health promotion approach

Suicide prevention programs at a national level in developed countries were briefly reviewed, and the community-based suicide prevention programs in Akita Prefecture, in the Tohoku Region of Japan, were also outlined. Suicide prevention programs were proposed in Western countries in the 1980s. A famous example is the national prevention program in Finland that was started in 1986. The national suicide prevention programs in Western countries share some common features such as their comprehensiveness and diversity. Typical policies of suicide prevention programs were categorized according to primary, secondary and tertiary prevention. Regarding community-based suicide prevention programs using a health promotion approach, the Akita prefectural government incorporated a suicide prevention program into the local health promotion strategy “Health Akita 21” in 2001. An outline of the four action programs was as follows: to raise awareness of suicide prevention, to increase opportunities for mental health consultation, to promote both primary and secondary prevention of depression, and to create a supportive environment for mental health promotion. Community-based suicide prevention programs were started in some communities of model projects that are financially supported by Akita Prefectural government. Efforts to evaluate the effectiveness of community-based suicide prevention programs are needed in the future.     

The role of the pediatrician in preventing suicide in adolescents with alcohol use disorders

Worldwide, suicide is among the top five causes of mortality in the 15- to 19- year age group. Pediatricians and primary care providers are in a distinctive position to help prevent suicide in adolescents. According to the Guidelines for Adolescent Preventive Services, all adolescents should have at least an annual preventive services visit, which should address both the biomedical and psychosocial aspects of health. Suicide prevention may best be accomplished by detection and management of specific risk factors, rather than by attempting to recognize those youth who are considered most likely to commit suicide. Alcohol use has been regarded as an important risk factor for adolescent suicidal behavior and the diagnosis of an alcohol use disorder indicates an elevated risk for adolescent suicide. Although the causal relationship between alcohol use and suicide remains unknown, a clear and strong relationship exists. Pediatricians and other health care providers should be skilled to recognize risk factors for adolescent suicide, including alcohol and drug misuse, depression, major loss, and recent suicides within a community. The relative frequency of suicidal behavior among adolescents suffering from alcohol use disorders and its distressing effects on individuals, families and society merits further research and development of prevention strategies in general pediatric settings.     

Association of adult body mass index and height with anxiety, depression, and suicide in the general population: the HUNT study

A prospective cohort of 74,332 men and women was used to investigate the association of body mass index and height with suicide, anxiety, and depression. Participants in the Nord-Tr?ndelag Health Study (Norway, 1984-1986) (HUNT 1) were aged 20 years or more and followed up until December 31, 2002. Anxiety and depression were measured with the Hospital Anxiety and Depression Rating Scale (HADS) in 1995-1997. There were 183 suicides. Suicide risk decreased with increasing body mass index at baseline (1984-1986) in men and women. In models controlling for a range of psychological, social, and lifestyle factors, the hazard ratio per standard deviation increase in body mass index was 0.82 (95% confidence interval: 0.68, 0.98). In contrast, in the subset of participants (n = 44,396) with HADS measures, body mass index at baseline (1984-1986) was positively associated with depression. In fully adjusted models, the odds ratio for depression per standard deviation increase in body mass index (HADS-D: > or =8) was 1.11 (95% confidence interval: 1.07, 1.15). In fully adjusted models, there was no association of height with the incidence of suicide or depression. Raised body mass index is associated with an increased risk of depression but reduced risk of suicide in men and women. The mechanisms underlying these different associations require clarification.     

Suicide risk factors among veterans: Risk management in the changing culture of the department of veterans affairs

Suicide risk management in the Department of Veterans Affairs (VA) health care system is particularly challenging because of both patient characteristics and aspects of the delivery system. The prototypical suicide-prone person is an older white male with alcoholism, depression, physical problems, and poor psychosocial support. This describes a large portion of the veteran patient population. Suicide risk factors that are common in VA patients include male gender, older age, diminished social environment support (exemplified by homelessness and unmarried status), availability and knowledge of firearms, and the prevalence of medical and psychiatric conditions associated with suicide. A variety of characteristics of the VA system complicate suicide management. Efforts under way to emphasize ambulatory care and decrease the VA culture of reliance on inpatient treatment heighten the importance of accurate suicide assessment. The authors recommend several strategies that VA administrators can consider for improving the assessment and management of veterans with long-term suicide risk factors.     

Increased toxicity to invertebrates associated with a mixture of atrazine and organophosphate insecticides

This study examined the joint toxicity of atrazine and three organophosphate (OP) insecticides (chlorpyrifos, methyl parathion, and diazinon) exposed to Hyalella azteca and Musca domestica. A factorial design was used to evaluate the toxicity of binary mixtures in which the lethal concentration/lethal dose (LC1/LD1, LC5/LD5, LC15/LD15, and LC50/LD50) of each OP was combined with atrazine concentrations of 0, 10, 40, 80, and 200 microg/L for H. azteca and 0, 200, and 2,000 ng/mg for M. domestica. Atrazine concentrations (> or = 40 microg/L) in combination with each OP caused a significant increase in toxicity to H. azteca compared with the OPs dosed individually. Acetylcholinesterase (AChE) activity also was examined for the individual OPs with and without atrazine treatment. Atrazine in combination with each of the OPs resulted in a significant decrease in AChE activity compared with the OPs dosed individually. In addition, H. azteca that were pretreated with atrazine (> or = 40 microg/L) were much more sensitive to the OP insecticides compared with H. azteca that were not pretreated with atrazine before being tested. Topical exposure to atrazine concentrations did not significantly increase OP toxicity to M. domestica. The results of this study indicate the potential for increased toxicity in organisms exposed to environmental mixtures.     

大学生自杀危险性与心理健康水平关系的研究

目的考察大学生的自杀危险性与心理健康水平的关系。方法采用大学生自杀危险性评定问卷（SRRS）和症状自评量表（SCL-90），对甘肃省三所高校的300名大学生进行调查。结果对两组变量的典型相关分析发现，两组变量之间存在中等程度的相关（典型相关系数是0．584）。构建的结构模型发现，心理健康的强迫因子对自杀态度和自杀动机有显著的正向作用，心理健康水平的抑郁因子和敌对因子对自杀危险性的负性情绪因子、态度因子、动机因子有显著的正向作用，精神病因子对认知僵化有显著的正向作用。结论大学生的自杀危险性与大学生的心理健康水平有直接的关系。     

Neurotoxicity of organophosphorus and dithiocarbamate compounds

The neurotoxicity of organophosphorus compounds (OPs) including leptophos, TOCP and triphenyl phosphite and dithiocarbamate compounds were reviewed in this study. The major neurotoxicities of OPs were acute toxicity produced by the acetylcholine esterase (AChE) inhibiting action of OPs and delayed neurotoxicity produced by such OPs as leptophos and TOCP. The direct action of OP on the muscarinic and/or nicotinic acethylcholine receptors in the synaptic membranes have lately attracted attention in relation to acute toxicity. Delayed neurotoxicity is a delayed onset of prolonged locomotor ataxia resulting from a single or repeated exposure to an OP. Although neurotoxic esterase (NTE) inhibition might be related to the onset of organophosphate-induced delayed neurotoxicity (OPIDN), the precise mode of action is not yet clear. The effect of dithiocarbamates on the nervous system is also mentioned, because the compounds are currently suspected not only for neurotoxicity, but also as endocrine-disrupting chemicals. Although dithiocarbamates showed weak neurotoxicity in adult animals, we need to pay more attention to developmental neurotoxicity.     

Suicide among nursing home residents: a population-based study

OBJECTIVE: The rate of suicide is highest among the oldest old and is associated with chronic medical illness and functional impairment. These risk factors are prevalent among nursing home (NH) residents, yet little has been published on suicide in this population. METHODS: We performed a population-based, retrospective cohort study to identify clinical features of NH residents attempting or completing suicide. A computerized data-base search was conducted to identify cases of completed suicide in Olmsted County and surrounding communities (846 NH beds) between 1981 and 1997. Subjects' medical records were reviewed to identify clinical details. RESULTS: Five cases of completed suicide and three suicide attempts were identified, including six men and two women. Deaths were the result of drowning, hanging, or medication overdose (the latter following a period of intentional hoarding). Those who died ranged in age from 69 to 87 years. Most had been NH residents for less than 6 months. No deaths occurred in patients with severe cognitive impairment. CONCLUSIONS: Suicide and suicide attempts in the NH seem to be uncommon but are likely underrecognized and underreported. Suicide risk among NH residents seems to be highest among men and those recently admitted to facilities. In addition, suicide methods differ among NH residents compared with community-dwelling older people, likely reflecting environmental restrictions and physical limitations. Suicide and suicide attempts are important resident health issues and risk management concerns for staff in long-term-care facilities.     

Suicide and Suicidal Behavior

Suicidal behavior is a leading cause of injury and death worldwide.Information about the epidemiology of such behavior is importantfor policy-making and prevention. The authors reviewed governmentdata on suicide and suicidal behavior and conducted a systematicreview of studies on the epidemiology of suicide published from1997 to 2007. The authors' aims were to examine the prevalenceof, trends in, and risk and protective factors for suicidalbehavior in the United States and cross-nationally. The datarevealed significant cross-national variability in the prevalenceof suicidal behavior but consistency in age of onset, transitionprobabilities, and key risk factors. Suicide is more prevalentamong men, whereas nonfatal suicidal behaviors are more prevalentamong women and persons who are young, are unmarried, or havea psychiatric disorder. Despite an increase in the treatmentof suicidal persons over the past decade, incidence rates ofsuicidal behavior have remained largely unchanged. Most epidemiologicresearch on suicidal behavior has focused on patterns and correlatesof prevalence. The next generation of studies must examine synergisticeffects among modifiable risk and protective factors. New studiesmust incorporate recent advances in survey methods and clinicalassessment. Results should be used in ongoing efforts to decreasethe significant loss of life caused by suicidal behavior. psychiatry • public health • risk factors • self-injurious behavior • suicide • suicide, attempted     

Suicide and attempted suicide in eating disorders, obesity and weight-image concern

Suicide in anorexia nervosa and bulimia nervosa is a major cause of death. Meta-analyses have shown that individuals suffering from anorexia nervosa and bulimia nervosa commit suicide more often than their counterparts in the general population; also a few studies have suggested that suicide is the major cause of death among patients with anorexia nervosa, refuting the assumption that inanition generally threatens the life of these patients. Data concerning suicide in bulimia nervosa, on the other hand, are still scarce but suicide attempts are easily found among cohorts of patients with bulimia nervosa, which constitutes a risk factor for completed suicide. Suicidality in obesity and individuals with disturbed weight status has been reported. Both in the case of bulimia nervosa and obesity more long-term follow-up studies need to be completed before the risk of suicide for such disorders may be compared with that for anorexia nervosa.     

Anti-depressants and suicide

Suicide takes the lives of around a million people each year, most of whom suffer from depression. In recent years there has been growing controversy about whether one of the best-selling anti-depressants – selective serotonin reuptake inhibitors (SSRIs) – increases or decreases the risk of completed suicide. Randomized clinical trials are not informative in this application because of small samples and other problems. We present what we believe are the most scientifically credible estimates to date on how SSRI sales affect suicide mortality using data from 26 countries for up to 25 years. We exploit just the variation in SSRI sales that can be explained by institutional differences in how drugs are regulated, priced, and distributed, as reflected by the sales growth of new drugs more generally. We find an increase in SSRI sales of 1 pill per capita (12% of 2000 sales levels) reduces suicide by 5%.     

家庭环境和应对方式对大学生自杀意念影响

目的 探讨家庭环境因素及应对方式对大学生自杀意念的影响.方法 采用随机抽样方法对某城市3所高校不同年级585名学生进行自杀意念、自伤行为、抑郁自评量表以及家庭环境和简明应对方式调查.结果 被调查者中有过自杀意念的占20.9％,5.7％有过≥1次自杀行为;11.6％的大学生有过自伤行为;自杀意念组的女生比例明显高于男生,曾经有过自杀和自伤行为的比例明显高于正常组(P＜0.001);多因素逻辑回归分析表明,女生(OR=2.391)、消极应对方式(OR =2.796)、抑郁状态(OR=1.071)、存在自伤行为(OR =4.003)以及有过≥1次自杀行为(OR =5.492)是大学生自杀意念的危险因素,而家庭环境亲密度(OR=0.879)可能是自杀意念的保护性因素;未发现童年时期父母的关系以及童年时期是否受到成年人虐待与大学生自杀意念相关.结论 大学生自杀意念较高,受性别、抑郁状态、家庭环境、消极应对以及曾经的自杀和白伤行为经验影响.     

Associations of substance use, abuse, and dependence with subsequent suicidal behavior

General population survey data are used to disaggregate the associations of substance use disorders with suicide attempts in order to evaluate a number of hypotheses about the processes leading to these associations. Data are from the US National Comorbidity Survey (1990-1992). Discrete-time survival analysis is used to study the effects of retrospectively reported temporally prior substance use, abuse, and dependence in predicting first onset of suicidal behavior. Alcohol and drug use predict subsequent suicide attempts after controlling for sociodemographics and comorbid mental disorders. Previous use is not a significant predictor among current nonusers. Abuse and dependence are significant predictors among users for three of the 10 substances considered (alcohol, inhalants, and heroin). The number of substances used is more important than the types of substances used in predicting suicidal behavior. Disaggregation shows that the effects of use are largely on suicidal ideation and nonplanned attempts among ideators. In comparison, the effects of use on suicide plans and planned attempts among ideators are not significant. Clinicians need to be aware that current substance use, even in the absence of abuse or dependence, is a significant risk factor for unplanned suicide attempts among ideators.     

Joint Toxicity of Triazine Herbicides and Organophosphate Insecticides to the Midge Chironomus tentans

A series of recent studies demonstrated that the triazine herbicide atrazine, although not itself acutely toxic, potentiated the toxicity of certain organophosphate insecticides (OPs) to the midge Chironomus tentans. In the current study, a series of triazine herbicides and triazine herbicide degradation products were tested to determine if other triazines potentiate OP toxicity to midges. Chlorpyrifos and diazinon were the OPs tested. Toxicity tests were conducted using a factorial design and analysis of variance to statistically determine if each triazine had an effect on expected toxicity. Log-probit procedures were also used to evaluate the magnitude of change in median effective concentration (EC₅₀) values during coexposure with each triazine. All of the triazine herbicides tested (atrazine, simazine, cyanazine, and hexazinone) were capable of potentiating the toxicity of the OPs, whereas the degradation products (s-triazine, deethylatrazine, and deisopropylatrazine) had less effect. In most cases, a triazine concentration of 100 μg/L was necessary to significantly increase OP toxicity, and higher concentrations of triazine caused a greater degree of potentiation. Changes in EC₅₀ values ranged from no change to a 2.5-fold increase in toxicity. Generally, EC₅₀ values changed by less than a factor of 2, indicating that the effect may be of limited concern in regard to future risk assessments of OPs.     

Development of toxicity identification evaluation procedures for pyrethroid detection using esterase activity

Recent agrochemical usage patterns suggest that the use of organophosphate (OP) pesticides will decrease, resulting in a concomitant increase in pyrethroid usage. Pyrethroids are known for their potential toxicity to aquatic invertebrates and many fish species. Current toxicity identification evaluation (TIE) techniques are able to detect OPs, but have not been optimized for pyrethroids. Organophosphate identification methods depend upon the use of piperonyl butoxide (PBO) to identify OP-induced toxicity. However, the use of PBO in TIE assays will be confounded by the co-occurrence of OPs and pyrethroids in receiving waters. It is necessary, therefore, to develop new TIE procedures for pyrethroids. This study evaluated the use of a pyrethroid-specific antibody, PBO, and carboxylesterase activity to identify pyrethroid toxicity in aquatic toxicity testing with Ceriodaphnia dubia. The antibody caused significant mortality to the C. dubia. Piperonyl butoxide synergized pyrethroid-associated toxicity, but this effect may be difficult to interpret in the presence of OPs and pyrethroids. Carboxylesterase activity removed pyrethroid-associated toxicity in a dose-dependent manner and did not compromise OP toxicity, suggesting that carboxylesterase treatment will not interfere with TIE OP detection methods. These results indicate that the addition of carboxylesterase to TIE procedures can be used to detect pyrethroids in aquatic samples.     

Suizidprävention im Alter

Elderly have the highest suicide rates and in the same time accept help only seldom. Suicide prevention in old age tries to reach persons with acute suicidality through screenings in depression and suicidality, but also with crisis intervention, psychotherapy and psychiatrical treatments. Further more groups with risk of suicide are reached especially through “gatekeeper”-trainings. Interventions on society level are concerned with the view on age and aging.