Bariatric Surgery Linked to Protection Against Severe COVID-19

— Obesity is a "modifiable risk factor" for severe COVID-19, researchers say

MedicalToday
A photo of surgeons performing a gastric bypass in the operating room

Substantial weight loss -- even if achieved through bariatric surgery -- improved COVID-related outcomes among people with obesity, a new study found.

People who underwent bariatric surgery prior to the pandemic saw a similar rate of positive COVID-19 test results as among propensity score-matched non-surgical controls of similar baseline BMI (9.1% vs 8.7%, P=0.71), reported Steven E. Nissen, MD, of the Cleveland Clinic, and colleagues.

But what happened after infection was a different story, the group reported in .

Despite a mean BMI still in the obese range (38.1) at the time of testing positive, the surgical weight loss group had nearly half the risk of hospitalization as controls, for whom mean BMI remained at 46.3 (adjusted HR 0.51, 95% CI 0.35-0.76, P<0.001).

Those who underwent weight loss surgery also saw a 63% lower risk for needing supplemental oxygen and a 60% lower risk for having a severe case of COVID-19, both statistically significant compared with nonsurgical controls.

"Because conducting clinical trials in this setting is not feasible, the findings of this study represent the best available evidence on the implications of a successful weight loss intervention for COVID-19 outcomes," Nissen's group explained. They added that this study clearly supported the notion that obesity can indeed be a "modifiable risk factor" for the severity of COVID infection.

The benefits of bariatric surgery also extended beyond COVID-19, as the surgical group saw a 53% lower 10-year cumulative incidence of death from all other causes (4.7% vs 9.4%, P<0.001).

Not surprisingly, those who underwent surgery lost 18.6% (95% CI 18.4-18.7%, P<0.001) more weight over the decade prior to the pandemic. So by the time these individuals tested positive for COVID-19, the surgical group patients achieved a 20.0-kg (44.1 lb) lower body weight and better glycemic control.

"COVID-19 infection is a proinflammatory and prothrombotic disease process that may be favorably altered by surgically induced weight loss through the amelioration of obesity-mediated hyperinflammation, hypercoagulopathy, and metabolic derangements," the researchers highlighted. They added that other benefits of bariatric surgery -- like improvement in breathing and lung mechanics, reduction in hypertension and other comorbidities like cardiovascular disease, sleep apnea, kidney function, and more -- also likely played a role in mitigating COVID-19 outcomes for these patients.

In an , Paulina Salminen, MD, PhD, of the University of Turku, Finland, and colleagues pointed out that these findings should reframe how people view bariatric surgery, especially at this time.

"In many countries, during the ongoing COVID-19 pandemic, metabolic surgery has been evaluated merely as an elective surgery that can be postponed with minimal adverse consequences," they wrote. "This approach, however, overlooks severe obesity as a life-threatening and life-limiting disease and does not acknowledge the intertwined double pandemic of COVID-19 and obesity."

The takeaway is simple, they wrote: Metabolic surgery should be considered as medically necessary -- not elective.

With the throwing support behind this mantra, Salminen's group referenced recent to help guide hospitals in resuming these clinically necessary procedures.

Nissen and colleagues' retrospective study observed a total of 20,212 patients for a median of 6.1 years. The 5,053 patients in the surgical group were matched 1:3 to patients who did not undergo for surgical intervention for their obesity.

As is typical with the bariatric surgery patient population, nearly 80% were female and baseline median BMI was 45. Two-thirds of the surgical population opted for Roux-en-Y gastric bypass and a third underwent sleeve gastrectomy.

COVID-related outcomes were assessed for those who tested positive between March 1, 2020, and March 1, 2021.

  • author['full_name']

    Kristen Monaco is a senior staff writer, focusing on endocrinology, psychiatry, and nephrology news. Based out of the New York City office, she’s worked at the company since 2015.

Disclosures

The study was funded by a grant from Medtronic.

Nissen and co-authors reported relationships with Medtronic, Novo Nordisk, Novartis, Boehringer Ingelheim, Merck, Bayer, the National Institutes of Health, the National Football League Players Association, the American Association for Thoracic Surgery, Eli Lilly, Abbvie, Silence Therapeutics, AstraZeneca, Esperion Therapeutics, Amgen, and Bristol Myers Squibb.

Salminen and co-authors reported relationships with Orion Pharma, Merck, Ethicon, Medtronic, Pacira, Persona, BD Surgical, Gore, GI Dynamics, Mediflix, SE Healthcare, and Keyron.

Primary Source

JAMA Surgery

Aminian A, et al "Association of weight loss achieved through metabolic surgery with risk and severity of COVID-19 infection" JAMA Surg 2021; DOI: 10.1001/jamasurg.2021.6496.

Secondary Source

JAMA Surgery

Salminen P, et al "Is COVID-19 the newest comorbidity of obesity mitigated by bariatric surgery?" JAMA Surg 2021; DOI: 10.1001/jamasurg.2021.6549.