Genetic link to suicide risk

Researchers from Johns Hopkins University in Baltimore have identified a gene that could be linked to an increased risk of attempting suicide. The researchers studied 2,698 people with bipolar disorder, 1,201 of whom had a history of suicide attempts. Those with one copy of a genetic variation on chromosome 2 were 1.4x as likely to have attempted suicide while those with two variations were almost three times as likely. The gene involved - ACP1 - leads to increased levels of a protein called ACP1 in the brains of people who had committed suicide. The protein is thought to influence the same biological pathway - albeit in a different direction - as lithium, a drug known to reduce the rate of suicidal behaviour.

Surveying suicide worldwide

A team of researchers led by Guilherme Borges from the Universidad Autonoma Metropolitana in Mexico has been looking into patterns and risk factors for suicide using information from the World Health Organisation's World Mental Health Surveys. The surveys were carried out between 2001 and 2007 and involved 108,705 adults from 21 countries. The researchers found that being young, being female, being less well-educated, unemployed, single, suffering from certain mental illnesses, having mentally-ill parents and having had a difficult childhood were all associated with increased suicidal behaviour. Suicide rates were similar in developed and developing countries although they were highest in Lithuania, Belarus and Russia and lower in Muslim countries. Social support and access to weapons or lethal substances were also important risk factors for suicide attempts.

Study show suicide peak in December for some groups

Researchers from the U.S. Substance Abuse and Mental Health Services Administration have been studying seasonal variations in drug-related suicide attempts. They analysed data from 2004 to 2008 and found that, on average, emergency departments dealt with 178,423 visits for drug-related suicide attempts by people aged 12 and over. For most groups there was little seasonal variation in suicide attempts but both boys (18.9%) and men over 50 (12.9%) were most likely to try and kill themselves in December. Boys were least likely to try and kill themselves in February (2.5%) while older men were least likely to commit suicide in October (5.5%).

Income inequalities and suicide risk

Because of the recent world economic crisis differences in health between rich and poor people have increased, differences which include mental health. Researchers from the World Psychiatric Association looked into this further in a study of depression, suicidal ideation and suicide attempts in South Korea between 1998 and 2007. The researchers found that these problems were more highly concentrated in lower-income groups. This inequality had got worse in recent years, especially in terms of suicide attempts, doubling over the past 10 years as income inequalities became more pronounced following the economic crisis. Over this period the suicide rate in South Korea doubled from 13 per 100,000 to 26 per 100,000 the highest rate among countries belonging to the Organisation for Economic Cooperatin and Development (OECD).

Suicide and depression - why the greatest risk is on the way back up

Paradoxically people being treated for major depression often experience more suicidal thoughts after they start treatment as they move from a state of complete passivity and acquire enough energy to think about suicide while still being profoundly depressed. A team of researchers led by Paola Rucci from the University of Pittsburgh School of Medicine studied this effect in 291 patients taking part in a trial comparing the effectiveness of interpersonal psychotherapy and treatment with serotonin-specific reuptake inhibitors (SSRIs). Of the 231 patients who weren't thinking of killing themselves at the start of the study 13.8% of them did think about ending it all at some point in the study. The participants taking SSRIs took longer to start thinking about killing themselves than those having psychotherapy. Of the 60 patients who were thinking about killing themselves at the start of the study seven showed more suicidal ideation after starting treatment. Overall though all the patients in the study managed their suicidal ideation successfully within the context of the study.

Rucci, P. ... [et al] - Treatment emergent suicidal ideation during 4 months of acute management of unipolar major depression with SSRI pharmacotherapy or interpersonal psychotherapy in a randomized clinical trial Depression and Anxiety DOI 10.1002/da.20758

Suicide risk and criminal justice

Previous studies have shown that prisoners are substantially more likely to kill themselves but little is known about increased risk among other people who have a brush with the law. Researchers from the University of Manchester and the University of Aarhus in Denmark studied 552,118 people in Denmark 27,219 of whom committed suicide. More than a third of all the men who killed themselves had a criminal-justice history although the relative risk was higher among women with a criminal-justice history. Suicide risk was markedly increased among people who had been in jail but the risk was even greater among people who had been sentenced to psychiatric treatment and who had had charges conditionally withdrawn. The risk of suicide was greater even in people who had not been sent to jail or who had been found innocent and was especially high in people who had had recent or frequent contact with the law or who had been charged with violent offences.

Webb, Roger T. ... [et al] - National study of suicide in all people with a criminal justice history Archives of General Psychiatry doi:10.1001/archgenpsychiatry.2011.7

Parents' divorce linked to increased risk of suicidal thoughts in men

Boys whose parents divorce could be more likely to think about killing themselves when they become adults. Researchers from the University of Toronto studied 6,647 adults of whom 695 had experienced their parents getting divorced while they were children. Once other factors such as parents being unemployed, being drug addicts or physically abusing their children were taken into account girls whose parents had divorced were no more likely to think about committing suicide; however, even after taking all these factors into account boys whose parents had split up were still twice as likely to think seriously about killing themselves.

Suicidal surgeons

A U.S. study by researchers from the Mayo Clinic in Rochester, Minnesota has found alarming levels of depression and suicidal thoughts among surgeons. Doctors are known to have a higher suicide rate than the rest of the population but this is thought to be because they have access to, and knowledge about, drugs. 7,905 surgeons - a response rate of 31.7% - answered a survey about depression and suicidal thoughts. 6.3% said they had thought about killing themselves in the last year. Older surgeons were more likely to report suicidal thoughts with surgeons who were 45 or over having one-and-a-half to three times the rate of suicidal thoughts as the rest of the population. Being married and having children were associated with lower levels of suicidal thoughts but being divorced raised the risk as did recently having made a surgical error or suffering from burnout. Only 26% of those who had had suicidal thoughts had sought help from a psychiatrist or psychologist.

Allergies, cytokines and suicide risk

People who have severe nasal or skin allergies could have a higher risk of suicide. Researchers from Aarhus University in Denmark analyzed the medical records of 27,000 people who had killed themselves. They found that just over 1% had been hospitalized for severe nasal allergies or eczema compared to 0.8% of the general population. Although the risk of suicide was small for both groups those with severe allergies had a 33% greater risk of committing suicide. Apart from the misery caused by the allergies themselves the researchers also thought that substances called cytokines, produced during allergic reactions, could be responsible. Cytokines can have depression-promoting effects and the study found that the people with allergies who had been treated for depression and anxiety actually had a lower suicide risk. This could be because the antidepressants used to treat these conditions also have the effect of damping down cytokines.

Psychosis and suicide

The long-term risk of suicide after a first episode of psychosis is unknown although most researchers think it is probably higher than the rate in the rest of the population. Researchers from the Institute of Psychiatry, King's College London studied 2,723 people in Camberwell, London; Nottingham and Dumfries and Galloway (Scotland) following them for 11 years after their first episode of psychosis. They found that although the rate of suicide was highest in the first year after becoming ill the increased risk persisted for years. Over the course of the study suicide among the participants occured nearly 12 times more than would be expected among the general population. 53 of the participants killed themselves over the course of the study, 49 more than would have been expected in a similar group of unaffected people. Even after ten years the suicide rate among the participants was four times as high as in the general population.

Dutta, Rina ... [et al] - Reassessing the long-term risk of suicide after a first episode of psychosis Archives of General Psychiatry 67(12), December 2010, 1230-1237

Pathological gambling and suicide

People with gambling problems are not only at risk financially they are also far more likely to kill themselves. 5% of people who kill themselves are pathological gamblers and gamblers are three times more likely to kill themselves than people who don't bet. Researchers from the Universite de Montreal studied 122 suicides which took place between 2006 and 2009, 49 of whom were pathological gamblers. The gamblers had twice as many personality disorders as the other suicides and were three times less likely to seek help before they killed themselves.

Parents' death and adolescent suicide risk

Most young people who lose a parent actually adjust remarkably well but a minority go on to develop mental-health problems which are, in turn, known to be a risk factor for suicide, something attempted by 5-8% of adolescents in Western societies. A Danish study - by researchers from the University of Southern Denmark and Odense University Hospital - looked into the links between parental death and suicide in a sample of 72,765 teenagers. They found that young people who had lost one biological parent had a 71% greater risk of going on to kill themselves than those whose parents were still alive while young people who lost more than one parent had a risk that was 2.7 times greater.

Jakobsen, Ida Skytte and Christiansen, Erik - Young people’s risk of suicide attempts in relation to parental death: A population-based register study Journal of Child Psychology and Psychiatry  (2010)doi:10.1111/j.1469-7610.2010.02298.x

Mental disorders and risk of suicide in veterans

Researchers from the Department of Veterans Affairs (VA) Healthcare System and the University of Michigan, Ann Arbor have been looking into the links between mental disorders and suicide in U.S. military veterans. They studied more than 3 million veterans who had received any type of care in a VA facility in 1999. They looked at their psychiatric diagnoses from their 1998 and 1999 treatment records and followed them over a seven-year period. By the end of the study 7,684 veterans had killed themselves. 46.8% of those who committed suicide had at least one psychiatric diagnosis and all of the diagnoses studied - depression, schizophrenia, bipolar disorder, drug abuse, post-traumatic stress disorder (PTSD) and anxiety - led to an increased risk of suicide. In men bipolar disorder was associated with the greatest risk of suicide while in the women drug abuse was - overall bipolar disorder led to the greatest increase in risk.

School grades and suicide risk

People who leave school early with low grades could be more likely to kill themselves. Researchers from the Karolinska Institutet and the Swedish National Board of Health and Welfare used some of the huge amounts of data which the Swedish state records about its citizens. They looked at the school-leaving grades - at age 16 - of almost 900,000 people born between 1972 and 1981 and tracked who later went on to kill themselves between the ages of 25 and 34. They found that those with the highest grades had the lowest risk of committing suicide while those with the lowest grades had a risk three times higher than average. The researchers took into account the educational level of the sample's parents, whether their parents were on benefit or single, the age of their mothers, their parents' mental health and drug use and whether they had been adopted.

You can find out more about this research here.

ADHD increases suicide risk

Children who are diagnosed with attention deficit hyperactivity disorder (ADHD) in early childhood are much more likely to have suicidal tendencies later. Researchers from Maryland University studied 248 children aged between nine and 18. Half of them had been diagnosed with ADHD as young children and half were unaffected. 12% of those who had been diagnosed with ADHD had thought about the practicalities of killing themselves compared to only 1.6% of the unaffected children.

Weight loss surgery and suicide risk

Very fat people sometimes have surgery to make their stomachs smaller and stop them eating so much. Researchers from the University of Pittsburgh studied 16,683 people who had had weight-loss surgery between 1995 and 2004. By 2006 31 of these people had killed themselves, a rate of 14 per 10,000 men per year and 5 per 10,000 women - a rate substantially higher than that for other men (2.5 per 10,000) and women (0.6 per 10,000). The researchers were unclear why more people should kill themselves after weight-loss surgery although previous studies have shown that people who have the operation are more likely to suffer from depression and anxiety beforehand.

Misery in the mountains

Living at high altitude could increase people's risk of committing suicide. Researchers from the University of Utah studied suicide rates in different US states. Those with the highest average altitudes - Montana, Idaho, Wyoming, Utah, Colorado, Nevada, New Mexico, Arizona and Oregon - were all in the top 10 for suicide rates. Although these states both have high levels of gun ownership and sparse populations (both risk factors for suicide) this did not explain the whole of the increased rates of suicide. A similar study in South Korea found that suicide rates increased by 125% in areas over 2,000m in altitude. Other research has shown that lack of oxygen at higher altitudes can lead to worsening mood which can last for up to 90 days - something which might be significant in people already suffering from mood disorders.

You can find out more about this research by clicking on the link in the title of this post.

Could new tests help suicide prediction?

Suicide is the fourth leading cause of death among adults under 65 in the U.S. so predicting who might kill themselves could save a considerable number of lives. At the moment most attempts at prediction are based on people's answers to a series of questions and - because people might not wish to own up to thoughts about suicide - are scarcely better than tossing a coin. Researchers at Harvard University have developed two tests that they hope will improve this process. In the first test the participants had to identify the colour of different words on screen, the idea being that suicidal individuals would pay more attention to words relating to suicide than other words. In the second test participants were tested on how strongly they associated themselves with words related to either life or death/suicide. The first test predicted suicide within the next six months more accurately than well-known risk factors such as a history of suicide attempts, patients' reported likelihood of an attempt and doctor's predictions. In the second test those participants with strong associations between themselves and death/suicide were six times more likely to attempt to kill themselves within the next six months.

You can find out more about this research by clicking on the link in the title of this post.

Drug use and suicide

In the U.S. suicide is the fourth leading cause of death in adults between 18 and 65. There is a link between drug problems and an increased risk of suicide but the specific risk factors among drug users are poorly understood. A team of researchers from the Ann Arbor Department of Veterans Affairs compared 854 drug users who killed themselves between 2002 and 2006 and 4,228 drug users who didn't. Of those people who killed themselves 70% did so by violent means such as shooting or hanging themselves or jumping off a tall building. Diagnoses of depression, anxiety, bipolar disorder and post-traumatic stress disorder (PTSD) were all associated with an increased risk of violent and non-violent (e.g. taking a deliberate overdose, gassing oneself) suicide. People who took drugs from the opium family or who took more than one kind of drug were more likely to kill themselves in a non-violent fashion.

Ilgen, Mark A. ... [et al] - Violent and nonviolent suicide in veterans with substance-use disorders Journal of Studies on Alcohol and Drugs July 2010, 71(4), 473-479

Child abuse and suicide

Suicide is one of the leading causes of death worldwide but what causes it is still not well understood. Mental-health problems are an important risk factor but most people with a mental-health problem do not think about killing themselves. There is strong evidence that people's experiences contribute more towards their mental-health problems than their genes and that bad experiences in people's childhood are linked to more thoughts about, or attempts at, killing oneself in later life. However, there has been less research into this than into genetic factors or mental-health problems. A team of researchers led by Ronny Bruffaerts from Gasthuisberg University Hospital in Belgium studied an international sample of 55,299 people asking them about their experiences in childhood and whether they had thought about, or tried to kill themselves. They found that bad experiences in childhood were associated with an increased risk of suicide attempts and thoughts of suicide. Sexual and physical abuse, especially during adolescence, were consistently the strongest risk factors.

Bruffaerts, Ronny ... [et al] - Childhood adversities as risk factors for onset and persistence of suicidal behaviour. British Journal of Psychiatry, July 2010, 197(1), 20-27