The number of self-harm emergencies increases by 50% after bariatric surgery, according to a report published online Oct. 7 in JAMA Surgery.
Mental health problems are common among both morbidly obese adults and patients undergoing bariatric surgery, and a recent meta-analysis of 30 studies found that suicide risk was four times higher among patients undergoing bariatric surgery than in the general population. To examine this association, researchers performed a population-based longitudinal cohort study comparing self-harm behaviors during the 3 years before bariatric surgery with those during the 3 years after bariatric surgery in all 8,815 adults who underwent gastric bypass, intestinal bypass, and sleeve gastrectomy in Ontario during a 5-year period.
This cohort reflects the practice of approximately 200 surgeons. Self-harm behaviors were categorized as medication overdose, alcohol-related, poisoning by toxic chemicals, or physical trauma. Approximately 64% of the study population had a history of anxiety disorders, 7.8% had general mental health disorders, and 0.6% reported alcohol misuse before undergoing bariatric surgery, wrote Junaid A. Bhatti, Ph.D., of the department of evaluative clinical sciences, Sunnybrook Research Institute, Toronto, and the department of surgery, University of Toronto.
There were 62 self-harm events during the preoperative interval and 96 during the postoperative interval. The mean incidence of self harm was 2.33 events per 1,000 patients during the 3 years before surgery and 3.63 per 1,000 during the 3 years after surgery, for a rate ratio of 1.54. This represents an increase of approximately 50% after bariatric surgery. The postoperative self-harm rate also was three times as high as that in the general Ontario population (1.2 per 1,000 people) during the same period.
Most of these incidents (73%) were medication overdoses. These were considered serious suicide attempts posing significant risk to the patients; they required ambulance transport and hospital admission. Physical trauma such as self-hanging accounted for another 21%. Almost all of the patients with postoperative self-harm behaviors had a known history of mental health problems, chiefly major depression. These findings suggest the need for increased screening and monitoring for excessive drug or alcohol use, as well as activating a reliable support network to mitigate the stress that follows profound changes in diet and lifestyle, Dr. Bhatti and his associates said (JAMA Surg. 2015 Oct 7. doi: 10.1001/jamasurg.2015.3414).
The reason for this rise in self-harm behaviors is not yet known. Some experts contend that changes in alcohol metabolism following bariatric surgery raise the likelihood of intoxication or alcohol-related disinhibition, both of which can escalate impulsivity. Others argue that morbid obesity arises from a food addiction, and after the procedure patients may turn from overeating to alcohol/substance abuse. Most agree that the surgery and the lifestyle changes it requires increase the patient’s stress and anxiety, which can exacerbate preexisting mental health problems. Finally, bariatric surgery itself alters neurohormone levels, which could in turn predispose patients to depression or suicidal behaviors, the investigators said.
This study was limited in that the data didn’t allow the researchers to account for some important surgery-related factors, including patients’ failure to lose a significant amount of weight. In addition, the study focused on self-harm behaviors that led to emergency-department visits; since completed suicides generally don’t include ED visits, some cases of self-harm that ended in death could not be included.
The Canadian Institutes of Health Research, the Canada Research Chair in Medical Decision Sciences, and the Da Souza Chair in Trauma Research funded the study. Dr. Bhatti and his associates reported having no relevant financial disclosures.