Why Do Obese People Have Higher Risk From COVID-19?

TUESDAY, Dec. 29, 2020 (HealthDay News) -- Respiratory problems and other factors -- not inflammation -- may explain why obese people are more likely to have severe COVID-19 and die from it, according to a new study.

Other studies have shown that overweight and obese COVID-19 patients are more likely to be admitted to intensive care, to require mechanical ventilation, and to die. Population-level studies also indicate that countries with higher obesity rates have higher COVID-19 death rates.

Inflammation had been suggested as a possible reason for the link between obesity and severe COVID-19.

"Though definitive reasons for poor COVID-19 outcomes in obesity remain uncertain, patients with obesity are uniquely vulnerable," said lead author Dr. Ana Mostaghim, who led the study during a residency in internal medicine at Boston Medical Center. "They may have independent risk factors [type-2 diabetes, hypertension and coronary artery disease] for poor outcomes in COVID-19, conditions that are inflammatory and immune-mediated."

To learn more, she and her colleagues compared outcomes and inflammatory markers in patients hospitalized with COVID-19.

The study looked at patients' body mass index (BMI), a measure of body fat based on height and weight, and their risk of ICU admission and death.

COVID patients who were severely obese (BMI of 35 or more) were twice as likely to be admitted to the ICU and had four times the risk of death from any cause. Those with a BMI of 30 to 34.9 also had a higher risk for ICU admission but not a significantly higher risk of death, according to the study.

Researchers found that obese patients had mostly lower inflammatory markers on their first two days in the hospital compared to patients who weren't obese.

"While patients with obesity had worse clinical outcomes than those without obesity in our study, this effect does not appear to be mediated by a higher degree of inflammation," said Dr. Natasha Hochberg, an associate professor of medicine at Boston University School of Medicine.

"Patients with obesity are at higher risk of fatty liver disease, and greater viral invasion with organ dysfunction may contribute to the increased mortality seen in these patients," she said in a university news release. "Alternately, patients with obesity may have reduced respiratory reserve."

The findings were published online Dec. 16 in the journal PLOS ONE.

More information

The U.S. Centers for Disease Control and Prevention has more on COVID-19.

SOURCE: Boston University School of Medicine, news release, Dec. 16, 2020