Anorexics are at a higher risk of death by suicide than the average person because they are more likely to choose deadlier methods like hanging and jumping in front of trains, a study suggested.
The findings, which will be published in the Journal of Affective Disorders this spring, provides insight into identifying patients at risk of carrying out lethal acts that would kill any person, regardless of their health, said lead author Jill Holm-Denoma, an assistant professor at the University of Vermont.
Anorexia nervosa is an eating disorder marked by unhealthy weight loss and self-starvation. Anorexics have a distorted self-image and an irrational fear of gaining weight or becoming fat, even when they are underweight.
The condition is often chronic, and anorexia has one of the highest premature death rates of all mental illnesses, according to the National Eating Disorders Association; between 5 and 20 per cent of anorexics will die due to the condition.
Suicide is a leading cause of death for anorexics and they already have a much higher suicide rate than seen in the general population, Holm-Denoma said.
"People with anorexia complete suicide at a rate that's about 57 times higher than the expected rate in similar populations that don't have anorexia."
There are two competing hypotheses for why the rate of suicide is so much higher for anorexics than in the general population, Holm-Denoma said. The first is that due to the nature of their condition, anorexics already have weakened health, which reduces their chances of surviving an attempt on their own lives -- basically, that a suicide attempt that might not kill a normal person could kill an anorexic.
"Therefore, they might be able to engage in what would be a relatively non-lethal suicide attempt for somebody of average health," she explained, "but they would end up dying just because they were so medically compromised."
The second hypothesis is that anorexics often die from suicide attempts because those attempts are more likely to involve lethal methods and scenarios with little chance of rescue.
That explanation is based on a theory Dr. Thomas Joiner published in his book "Why People Die By Suicide," Holm-Denoma said.
"What he predicts is that people who have multiple experiences with self-harm early in their life eventually acquire the capacity to engage in highly lethal forms of self-injury," she said. Individuals who have a history of causing themselves harm or who have endured multiple painful or provocative experiences -- such as abuse or serious injury -- are more likely to harm themselves in ways that could kill them.
The theory does not apply only to anorexics, but the nature of anorexia nervosa involves a significant amount of self-harm, Holm-Denoma said. Anorexics starve themselves to the point of physical pain, and many of the effects of that starvation also lead to suffering.
"Some people are so underweight that even laying in bed is painful to them," she said. Many anorexics also engage in other self-harm behaviors aside from those directly associated with the disease.
"Stemming from this theory," Holm-Denoma said, "we predicted that people with anorexia would have worked themselves up to be able to engage in highly lethal suicide methods."
To test the hypothesis, Holm-Denoma and her team examined case studies of anorexics who had received in-hospital treatment. Looking at patients who had been admitted to a hospital or care facility for treatment of anorexia nervosa, they examined nine who had attempted suicide and died.
The study found the majority of the deceased patients chose methods of suicide that would kill a healthy person: two hung themselves, and three jumped in front of a train. One woman killed herself via carbon monoxide poisoning, and another ingested toilet bowl cleaner. The other patients died of drug overdoses. Several patients had tried to kill themselves previously.
Most of the patients also had taken some measures to prevent someone from interrupting the suicide attempt, for example, by committing suicide in an isolated location, lowering their risk of rescue.
It's not only the severity of the method that's striking, but also the gender of the victims. All nine cases in the study were women, and 90 to 95 percent of people diagnosed with anorexia are female, according to the American Psychiatric Association.
"We have a lot of empirical evidence to suggest that in general, women attempt suicide at higher rates than men, but they actually die by suicide much less frequently than men do," Holm-Denoma said. This is because women generally choose less lethal methods when they attempt suicide - drug overdoses versus firearms, for example and therefore are more likely to survive a suicide attempt.
But because the methods chosen by the subjects in the study were deadlier, they died from them more often - their sample was over 100 times more likely to die from suicide than average, Holm-Denoma said, even higher than other studies have shown for anorexics.
"We're seeing a high rate of completed suicide in this group, which flies in the face of what we know for the general population."
The findings can help increase the awareness of the risk of suicide and suicide attempts in people suffering from anorexia nervosa, Holm-Denoma said, particularly among care-givers like physicians.
Doctors can do regular suicide assessments with their patients, she suggested, asking their patients about self-harm or painful experiences in an attempt to identify those that may be at a higher risk of making attempts on their own lives. When those patients are identified, physicians should intervene specifically with treatments not just for anorexia but also for suicide, she said.
Because the study is not empirical, it doesn't allow for conclusive discussion of cause and effect, Holm-Denoma said. As well, the subjects were followed for about 13 years from the time they first received treatment for anorexia nervosa, she said, which makes these results preliminary; in order to come to conclusive results about the final suicide rates, the patients would have to be followed until they all died, from suicide or other causes.
As well, the people in the study were all anorexics who received intensive treatment for the condition at a hospital, Holm-Denoma pointed out.
"There's actually some literature to suggest that people who end up seeking treatment in these major hospitals have more severe cases of anorexia than maybe the prototypical case," she said, "so it's possible that some of the results that we're seeing could be at least in part explained by the severity of these individuals' anorexia." Further study could look at anorexics who had the disease but didn't reach the point of in-hospital treatment for it.
"I think the first thing is just to remind people that individuals with anorexia are at a much higher risk of dying by suicide than the average person," Holm-Denoma said. "Just having that awareness is important."