(CNN) Surgery is meant to improve a person's health and quality of life, but there are some cases where it may have the opposite effect.
Bariatric surgery may be one of these, because it could increase a person's risk of self-harm, according to a new study.
Researchers in Canada included nearly 9,000 adults in Ontario who had bariatric surgery, most commonly Roux-en-Y gastric bypass, between 2006 and 2011. They looked at how many times those patients went to the emergency room for trying to harm themselves, such as by drug overdose or physical injury, in the three years before and after surgery.
The researchers found that, even before surgery, people in the study were about twice as likely to hurt themselves as the general population. There were 2.33 incidents out of 1,000 patients each year before surgery in the study group.
However, the risk increased even more after surgery; there were 3.63 incidents for every 1,000 people each year during this period. Many of the cases overall had to be rushed to the hospital and involved a hospital stay.
People with obesity, such as those in this study, have higher rates of mental health problems, such depression and substance misuse, although the reasons are not clear. Experts have suggested that increases in stress hormones and inflammation associated with obesity could contribute to depression.
There are also a lot of reasons why having bariatric surgery could drive up that risk even further, said Dr. Amir A. Ghaferi, assistant professor of surgery at the University of Michigan Health System. Ghaferi was not involved in the current study, but he wrote an editorial about it, and both were published Wednesday in the medical journal JAMA Surgery.
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Although the risk of self-harm is still small, there is an important increase in the years before and after surgery, Ghaferi said, adding that he would be "extremely shocked" if it did not have something to do with the operation.
"The operation affects so much physiologically but also socially for the patient and I think all of those are going to contribute to the increased risk" of self-harm, and potentially suicide, Ghaferi said.
For example, some of Ghaferi's patients have told him they feel stigmatized for having bariatric surgery and that their peers might think they should have been able to lose weight through diet and exercise. Others lack the support of loved ones who are overweight and may feel threated by their weight loss.
One of the biggest problems is that many patients stop coming to follow-up appointments, which are recommended every few weeks or months in the first year following surgery and annually afterward. Surgery is a lot less traumatic these days, and patients recover faster, but the downside is they are evaluated less regularly, both for physical and mental health, Ghaferi said.
The study found that most of the self-harm emergencies took place in the second and third year after surgery. In addition, they were more common in people older than 35, and those who were low income or lived in rural areas. The latter two groups in particular might have a harder time making follow-up appointments.
Typically people have to receive a mental health evaluation before getting approval for bariatric surgery because nearly every insurance carrier requires it, Ghaferi said. During these sessions, a mental health expert takes a thorough look at whether the candidate will likely be able to cope with, and have enough social support for, life after surgery, which includes drastic dietary restrictions.
These experts are often able to identify patients who are at risk for mental health problems. And although they can require the patients to get help before surgery, all they can do after surgery is recommend follow-up visits, Ghaferi said. "It would be nice if insurance could mandate this but how do you enforce it," he added, "and do you withhold reimbursement" for patients if they do not?
Even if patients make it to follow-up visits and a clinician recommends they get some kind of mental health care, "it's up to them to carry through with that, and it's not always covered through insurance programs," said Dr. William S. Richardson, a specialist in bariatric surgery and section head of general surgery at Ochsner Medical Center in New Orleans. There needs to be better mental health coverage and less stigma around getting help, he added.
"What this study really shows overall is that we are not taking psychiatric care in general as seriously as we need to ... and certainly in the obese population. We need to work on their psychiatric problems," Richardson said.
However, neither Richardson nor Ghaferi said they think mental health therapy should be required after bariatric surgery because rates of self-harm are still low overall. In addition, it would not be fair to treat these patients any differently than the general population, Ghaferi said.
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Several other types of surgery typically require patients to receive a mental health evaluation beforehand, including gender reassignment. Reports have found high rates of psychiatric illness before and years after gender reassignment procedures.
Some cosmetic surgery centers also conduct psychiatric consultation before elective procedures, such as rhinoplasty, to help ensure patients are not motivated to have surgery because of a body image disorder, anxiety or other mental health problems. Those with a body image disorder, which is relatively common in this group, are often dissatisfied with the results of the procedure and may even develop anger or depression afterward.
Even for surgeries that do not involve a formal mental health check preoperatively, doctors usually chat with patients about their post-operation plan and encourage them to build a support system to help them recover, Ghaferi said. "It is not by a mandate but as a moral obligation," he added.