Death Risk Drops After Bariatric Surgery in Obese Patients

Adapted from an article by by Kristen Monaco, Staff Writer, MedPage Today

In a recent study Bariatric surgery was associated with an extended lifespan in patients with obesity, according to a French study. In a patient study of nearly 9,000 bariatric surgery patients, those who underwent gastric bypass surgery had a 36% reduced mortality risk compared with matched controls with obesity who did not undergo surgery, reported Jérémie Thereaux, MD, of the Caisse Nationale d’Assurance Maladie in Paris, and colleagues.

During the nearly 7-year follow-up period, patients who opted for sleeve gastrectomy saw a 62% reduced risk for mortality versus those who didn’t undergo surgery, they stated in the Lancet Diabetes & Endocrinology.

Thereaux’s group underscored the importance of a careful “benefit-risk balance” individualized to the patient prior to deciding to undergo bariatric surgery, emphasizing that patients “must be aware that they will have to comply with multidisciplinary careful lifelong follow-up given the risk of late adverse events.”

It is important to note that prolonged mortality associated with bariatric surgery also came with some additional medical risks. Patients who underwent gastric bypass surgery saw a higher incidence of a few gastrointestinal (GI)-related outcomes:
Invasive GI surgery or endoscopy: incidence rate ratio 2.4 (95% CI 2.1-2.7)
GI disorders not leading to invasive procedures: IRR 1.9 (95% CI 1.7-2.1)
Nutritional disorders: IRR 4.9 (95% CI 3.8-6.4)
Those who underwent sleeve gastrectomy also saw a significantly higher incidence for these outcomes, although not to the same extent as seen with the more invasive gastric bypass procedure:
Invasive GI surgery or endoscopy: IRR 1.5 (95% CI 1.3-1.7)
GI disorders not leading to invasive procedures: IRR 1.2 (95% CI 1.1-1.4)
Nutritional disorders: IRR 1.8 (95% CI 1.3-2.5)
Out of all the GI adverse outcomes, the most common events for gastric bypass patients were gastroesophageal reflux disease or gastritis and other upper gastrointestinal symptoms. The most common event for sleeve gastrectomy patients was small bowel obstruction.

The authors found that psychological health was seemingly unaffected by bariatric surgery. Compared with nonsurgical controls, there wasn’t any increased incidence in psychiatric disorders after gastric bypass, or sleeve gastrectomy. The research group noted that when they added “psychiatric disorders coded as associated diagnoses to those coded as primary diagnosis, the gastric bypass and sleeve gastrectomy groups had a lower risk of psychiatric disorders than did their control groups.”
Neither surgery was associated with an increased incidence of post-operative suicide attempt at an IRR 1.1 (95% CI 0.9-1.4) for gastric bypass and an IRR 1.3 (95% CI 0.9-1.7) for sleeve gastrectomy.

Previous studies have reached mixed conclusions on the risk of suicide after bariatric surgery, “These comparisons must be interpreted cautiously because only suicide attempt was assessed in our study, and patient characteristics differ from one study to another,” Thereaux’s group stated.
However, those who underwent gastric bypass specifically did see a slightly higher incidence of alcohol dependence after surgery that was not seen in the sleeve gastrectomy group, they noted.

The population-based study, which drew upon patient data from the French National Health Insurance database, included 4,955 patients who underwent gastric bypass and 4,011 who underwent sleeve gastrectomy in 2009. They were matched with individuals who were admitted to a hospital that year for obesity. Those who had undergone a previous bariatric surgery procedure within 4 years prior were excluded.

Study limitations included a lack of other relevant information taken into consideration, the commentators noted, such as post-operation follow-up visits with a dietitian and psychologist, as well as information of vitamin supplementations used. This information was not recorded in the database.
“No information was available as to whether there were more complications in those patients with a less frequent follow-up and whether only surgeons or whether a multidisciplinary team including endocrinologists, dietitians or nutritionists, and psychologists were involved in the follow-up visits,” Unamuno and colleagues pointed out.

Thereaux’s group underscored the importance of a careful “benefit-risk balance” individualized to the patient prior to deciding to undergo bariatric surgery, emphasizing that patients “must be aware that they will have to comply with multidisciplinary careful lifelong follow-up given the risk of late adverse events.”