New studies presented at this year's European Congress on Obesity in Vienna showed that obese persons are better in surviving infections than their healthier counterparts.
Researchers investigated how survival rates for infectious diseases, pneumonia, and sepsis are different between obese people and those with healthy body mass index. This finding is tagged as an "obesity paradox" to illustrate contradictions to an overwhelming wealth of study citing increased mortality among obese patients.
The European Congress on Obesity is held on March 23 to 26 in Vienna, Austria.
Results Of The Studies
A Danish study investigated the death rates of patients admitted to hospitals between 2011 and 2015 due to infectious diseases. They assessed the mortality 90 days after the patients were discharged, while other factors such as smoking, cancer, and recent weight change were considered.
Lead author Sigrid Gribsholt from Aarhus University Hospital's department of clinical epidemiology in Denmark reported that overweight and obese patients had 40 percent and 50 percent less likelihood to die compared to those with normal weight.
Gribsholt explained the reason being could be that obesity caused inflammation, which sends a strong impulse to the immune system to fight infection. She added that obese people have more energy that they are less likely to feel wasted in effect of their disease.
"They have larger energy reserves, which may also be protective," Gribsholt said.
The second study looked at 1.7 million pneumonia-induced hospital admissions in the United States from 2013 to 2014 and found that overweight and obese patients had respective 23 percent and 29 percent survival rates.
Patients in the United States who were admitted to hospitals due to sepsis or blood poisoning, also showed similar survival rates. Overweight patients had 23 percent survival rate, and obese patients are 22 percent less likely to die.
"We found that increase in BMI was significantly associated with improved survival and lowered readmission among hospitalized patients with sepsis. Our results suggest that BMI may be used for risk stratification of patients with sepsis," the authors wrote.
Premature Death Caused By Obesity
Meanwhile, a study conducted by researchers at the Harvard T.H. Chan School of Public Health and the University of Cambridge in the UK contradicted the so-called obesity paradox and suggested that overweight or obesity is linked to higher risks of premature deaths.
The study, which was published in July 2016 in the journal Lancet, cited that the obesity paradox has caused confusion to the public on the role of weight associated with certain diseases.
Coauthor Frank Hu, a professor of nutrition and epidemiology at the Harvard Chan School, reported that prior studies have a methodological limitation. This research gap called reverse causation suggests that a low body weight is the cause of underlying or preclinical illnesses rather than the other way around.
"To obtain an unbiased relationship between BMI and mortality, it is essential to analyze individuals who never smoked and had no existing chronic diseases at the start of the study," Hu said.
The researchers emphasized the importance of physician counseling on the role of body weight in the risks of diabetes, cancer, and heart diseases.
