hospital bedObese patients, defined as having a BMI >30 kg/m2, who were hospitalized with pneumonia, were less likely to die than were their normal weight counterparts, according to researchers at the University of Alberta. Neither underweight nor overweight was independently associated with lower short-term mortality, the team noted.

“The thinking usually is obesity equals bad and this research demonstrated something different. It shows that perhaps we’re not looking at obesity in the right way,” said lead author Sharry Kahlon, who works in the Department of Medicine and is a resident in internal medicine. “Is all fat bad? Is all fat equal? For acute illnesses, maybe we’re not looking at the right indicators for body mass index and obesity.”

Kahlon noted the research supports the “obesity paradox,” which indicates that, in some circumstances, being obese may be better for your health, despite obesity’s association with an increased risk of diabetes, hypertension, death, and catching infections like pneumonia.

For the study, researchers examined the records of 907 patients with pneumonia who were admitted to six different hospitals. Two-thirds of the patients had severe pneumonia and 79 died in hospital. Of those who died, 12 were underweight, 36 were normal weight, 21 were overweight, and 10 were obese. Mortality was 10% for those who were normal weight and 4% for those who were obese. This translates into a 54% reduction in mortality associated with being obese.

Kahlon noted obese patients may have had better survival rates because they had more nutritional reserves, adding that it might be a misregulation of the inflammatory system that allows these individuals to do better. She also noted physicians may need to adjust prescriptions or care for obese patients hospitalized with pneumonia to better meet their medical needs.