How does obesity raise risks for severe COVID? CDC report looks at the data

An analysis of nearly 150,000 COVID-19 patients across the nation found that adults with obesity faced higher risks for hospitalization, invasive mechanical ventilation and death, especially among individuals younger than 65, than those in healthy and overweight categories.

About 51% of coronavirus patients in the study had obesity, compared to about 42% of adults in the U.S. population, suggesting that individuals affected by obesity are more likely to develop severe COVID-19, with risks increasing as body mass index (BMI) does, according to the Centers for Disease Control and Prevention report released Monday.

The study comes as states begin to open access to COVID-19 vaccines for people with obesity, which the CDC considers a high-risk medical condition. That’s because the disease is also a risk factor for other chronic conditions, such as type 2 diabetes, heart disease and some cancers.

Authors of the report also highlight the need to “promote and support healthy BMI” for Hispanic, Latinx and Black adults, as well as individuals from low-income homes, who are disproportionately affected by obesity and are more likely to suffer worse outcomes from COVID-19 compared to white people.

“As clinicians develop care plans for COVID-19 patients, they should consider the risk for severe outcomes in patients with higher BMIs, especially for those with severe obesity,” the report said. “These findings highlight the clinical and public health implications of higher BMIs, including the need for intensive COVID-19 illness management as obesity severity increases, promotion of COVID-19 prevention strategies including continued vaccine prioritization and masking, and policies to ensure community access to nutrition and physical activities that promote and support a healthy BMI.”

The CDC analyzed data on 148,494 adults with COVID-19 who were admitted to one of 238 hospitals in the U.S. between March and December 2020 — about 28% of patients were considered overweight and about 51% were considered obese.

Risks for coronavirus-related hospitalization, admission into an intensive care unit and death were lowest among patients with BMIs in the healthy and overweight categories, but those risks “increased sharply” with increasing BMI, the report said.

The researchers said their findings support the hypothesis that people affected by obesity may face high risks for severe disease because of inflammation caused by excess weight that disrupts immune responses to viruses such as the novel coronavirus. Impaired lung function from excess weight may also contribute to increased risks, the report said.

Similar high risks were found among people in the underweight category.

Adults who had BMIs that were considered underweight had a 20% higher risk of hospitalization than those with BMIs in the healthy weight category. The researchers say this “could be explained by uncaptured underlying medical conditions or impairments in essential nutrient availability and immune response.”

Only adults who received care at a hospital and had their height and weight reported in their medical records were included in the study, the report said, which may affect the true nature of risks people with obesity and COVID-19 face. And although a large number of patients were studied, the results are still “not representative of the entire U.S. patient population,” according to the CDC.