In a large California health care plan, among patients with COVID-19, men aged 60 years and younger had a much higher risk of dying within 3 weeks of diagnosis if they had severe obesity as opposed to being of normal weight, independently of other risk factors.
reported Sara Y. Tartof, PhD, MPH, Kaiser Permanente Southern California, Pasadena, Calif., and coauthors.
The data “highlight the leading role of severe obesity over correlated risk factors, providing a target for early intervention,” they concluded in an article published online Aug. 12 in Annals of Internal Medicine.
This work adds to nearly 300 articles that have shown that severe obesity is associated with an increased risk for morbidity and mortality from COVID-19.
In an accompanying editorial, David A. Kass, MD, said: “Consistency of this new study and prior research should put to rest the contention that obesity is common in severe COVID-19 because it is common in the population.”
Rather, these findings show that “obesity is an important independent risk factor for serious COVID-19 disease,” he pointed out.
On the basis of this evidence, “arguably the hardest question to answer is: What is to be done?” wondered Kass, of Johns Hopkins University, Baltimore.
Although data consistently show that a body mass index >35 kg/m2 is predictive of major health risks, “weight reduction at that level of obesity is difficult and certainly is not achieved rapidly,” Dr. Kass stressed.
“Therefore … social distancing; altering behaviors to reduce viral exposure and transmission, such as wearing masks; and instituting policies and health care approaches that recognize the potential effects of obesity should be implemented,” he emphasized. “These actions should help and are certainly doable.”
Similarly, Dr. Tartof and colleagues said their “findings also reveal the distressing collision of two pandemics: COVID-19 and obesity.
“As COVID-19 continues to spread unabated, we must focus our immediate efforts on containing the crisis at hand,” they urged.
However, the findings also “underscore the need for future collective efforts to combat the equally devastating, and potentially synergistic, force of the obesity epidemic.”
COVID-19 pandemic collides with obesity epidemic
Previous studies of obesity and COVID-19 were small, did not adjust for multiple confounders, or did not include nonhospitalized patients, Dr. Tartof and coauthors wrote.
Their study included 6,916 members of the Kaiser Permanente Southern California health care plan who were diagnosed with COVID-19 from Feb. 13 to May 2, 2020.
The researchers calculated the risk for death at 21 days after a COVID-19 diagnosis; findings were corrected for age, sex, race/ethnicity, smoking, myocardial infarction, heart failure, peripheral vascular disease, cerebrovascular disease, chronic pulmonary disease, renal disease, metastatic tumor or malignancy, other immune disease, hyperlipidemia, hypertension, asthma, organ transplant, and diabetes status.
On the basis of BMI, the patients were classified as being underweight, of normal weight, overweight, or as having class 1, 2, or 3 obesity. BMI of 18.5 to 24 kg/m2 is defined as normal weight.
Class 3 obesity, also called severe obesity, included moderately severe obesity (BMI, 40-44 kg/m2) and extremely severe obesity (≥45 kg/m2).
A little more than half of the patients were women (55%), and more than 50% were Hispanic (54%).
A total of 206 patients (3%) died within 21 days of being diagnosed with COVID-19; of these, 67% had been hospitalized, and 43% had been intubated.
Overall, the COVID-19 patients with moderately severe or extremely severe obesity had a 2.7-fold and 4.2-fold increased risk for death, respectively, within 3 weeks compared with patients of normal weight.
Patients in the other BMI categories did not have a significantly higher risk of dying during follow-up.
However, each decade of increasing age after age 40 was associated with a stepwise increased risk for death within 3 weeks of the COVID-19 diagnosis.