Obesity may offer protection when severe infection strikes

SUNDAY, May 27, 2018 -- Obesity brings with it many health ills, but there could be one silver lining, new research shows.

If you're in the hospital with an infectious disease, you're half as likely to die if you're overweight or obese, Danish researchers report.

For the study, Sigrid Gribsholt, from Aarhus University Hospital's department of clinical epidemiology, and colleagues collected data on more than 35,000 patients hospitalized for infections from 2011 to 2015.

Among these patients, the investigators looked at whether weight affected the risk of dying in the three months after discharge.

Gribsholt's team found that for underweight patients, the risk of dying was two times higher than for patients of normal weight. That seemed tied, however, to recent weight loss due to some underlying disease. Deaths did not increase for underweight patients who had not recently lost weight.

The surprise finding was that overweight patients were 40 percent less likely to die and obese patients were 50 percent less likely to die, compared with normal-weight patients.

Among obese patients, whether they had recent changes in weight, other medical conditions or if they smoked had little effect on the risk of dying, the findings showed.

"Overweight and obesity were associated with substantially reduced 90-day mortality following incident hospital admission for infection," the researchers wrote.

The results of the study were presented May 24 at the European Congress on Obesity in Vienna, Austria.

Similar findings arose in three other studies also presented at the meeting:

In a study jointly conducted by researchers in the United States and Taiwan, a look at the medical records from nearly 1.7 million Americans hospitalized with pneumonia found that the odds of dying fell by 20 percent to 30 percent if the patient was overweight or obese.
A study conducted by the same team, using the same database, found that hospitalized overweight or obese patients were also about 22 percent to 23 percent less likely to die from the blood infection sepsis, compared to normal-weight patients.
A study led by Dutch researchers at the Erasmus MC, University Medical Center Rotterdam found that, in a group of 26 seriously ill patients, the nine who were obese were less likely to undergo rapid muscle wasting compared to their normal-weight peers.

But obesity expert Dr. Mitchell Roslin said the so-called "obesity paradox" -- where a normally unhealthy weight appears to have some health benefit -- "has to be kept in perspective."

Even though excess weight might somehow offer protection in dire circumstances, obesity is linked to a number of deadly diseases, including diabetes, heart disease and even some cancers.

"What is happening today is that the obesity epidemic is causing far more [ill health] than it is protecting," said Roslin, who is chief of obesity surgery at Lenox Hill Hospital in New York City.

"Just because you are overweight does not mean you are unhealthy," he said, but "if your obesity is severe, it is unlikely you are healthy."

The new findings were all presented at a medical meeting, and as such should be considered preliminary until published in a peer-reviewed journal.

More information

For more about obesity, visit the U.S. Centers for Disease Control and Prevention.