(Reuters Health) - Obese people with chronic obstructive pulmonary disease (COPD) who get weight loss surgery may go to the hospital less often with acute breathing problems after their operations, a U.S. study suggests.

Among obese adults with COPD who had what’s known as bariatric surgery to lose weight, the proportion of patients who needed emergency room or inpatient hospital care for the lung disorder fell by more than half after the operations, the study found.

“If you are morbidly obese and suffering from COPD, bariatric surgery could mitigate COPD-related symptoms,” said lead study author Dr. Tadahiro Goto, an emergency medicine researcher at Massachusetts General Hospital in Boston.

COPD is usually caused by smoking, and symptoms include breathing difficulty, cough, excessive phlegm production, and wheezing.

Treating obesity in patients with COPD is controversial because that excess weight has been linked to both worse lung function and better survival odds, Goto said by email. Recently, some small studies have suggested weight loss might benefit COPD patients, but the current study is the largest to date to provide evidence that bariatric surgery may help ease severe symptoms, Goto added.

The researchers examined data on 481 obese adults aged 40 to 65 who had COPD and underwent bariatric surgery in California, Florida and Nebraska.

They followed patients from 2005 through 2011 to see how hospital and emergency room visits for COPD in the two years before weight loss surgery compared to the two years afterwards.

At the start of the study, when patients were 13 to 24 months away from getting their operations, 28 percent of them had an emergency department (ED) or hospital visit for acute COPD symptoms, researchers report in Chest.

During the second year of the study, the 12 months right before surgery, these rates didn’t change much.

But compared with that first year of the study, the chances of an ED or hospital visit dropped by 65 percent in the first year after bariatric surgery. Just 12 percent of patients had a COPD visit during that time.

During the last year of the study, 13 to 24 months after surgery, the odds of an ED or hospital visit were 61 percent lower than in the first year of the study.

One limitation of the study is that it focused on people with severe COPD symptoms, and the results might not apply to people with well-controlled disease, the authors note.

It’s also possible that insurance might not cover bariatric surgery or that some patients might not be good candidates for the operations, said Linda Simoni-Wastila, a researcher at the University of Maryland School of Pharmacy in Baltimore who wasn’t involved in the study.

“Surgery of any kind adds risk, and if less invasive ways of lowering weight can be managed, then those ways would be preferable,” Simoni-Wastila said by email. “Bariatric surgery would not be ideal in individuals with moderately severe to end-stage COPD, nor would it be an option in older adults.”

Still, the findings suggest that benefits of bariatric surgery may extend beyond remission of chronic health problems like diabetes to include COPD and other respiratory conditions, said Dr. Ninh Nguyen, chief of gastrointestinal and bariatric surgery at the University of California, Irvine School of Medicine.

While the study doesn’t show why weight loss surgery might help control COPD symptoms, obesity impairs many aspects of respiratory mechanics that can make acute breathing problems more likely, Nguyen, who wasn’t involved in the study, said by email. Improved breathing mechanics and lower inflammation after surgical weight loss might both help ease COPD symptoms, Nguyen added.

“It does not take a tremendous amount of weight loss to achieve health benefits,” Nguyen said. “A reduction of weight as small as 5 to 6 percent of body weight can be beneficial.”

SOURCE: bit.ly/2vStLvf Chest, online July 14, 2017.