CDC study strengthens link between higher BMI and severe disease

New research from the CDC adds to the evidence linking obesity with progression to severe Covid-19, with the lowest risk for hospitalization shown among those whose weight was near the threshold between healthy and overweight.

The retrospective analysis included nearly 150,000 adults with Covid-19 who visited emergency departments or were treated as inpatients at more than 200 U.S. hospitals between March and December of 2020.

Obesity was a risk factor for hospitalization and death, especially among adults older than 65 years of age, with severe obesity (BMI ≥45) associated with a 61% increased risk for death.

Hospitalization risk was 33% higher among patients with BMIs greater than 45 kg/m2, compared to the reference group of patients with BMIs between 18.5 and 24.9 kg/m2.

Compared to this reference group, hospitalization risk was 7% higher, 14% higher, and 20% higher, respectively, among patients with BMIs of 30-34.9, 35-39.9 and 40-44.9 kg/m2. People with body mass indexes just above the normal range (BMI of 24 to 26 kg/m2) had the lowest risk for hospitalization, mechanical ventilation, and death due to Covid-19.

“The findings in this report highlight a dose-response relationship between higher BMI and severe Covid-19-associated illness and underscore a need for progressively intensive illness management as obesity severity increases,” Lyudmyla Kompaniyets, PhD, and fellow CDC researchers wrote in the latest Morbidity and Mortality Weekly Report, published online March 8.

Half (50.8%) of the Covid-19 patients included in the analysis were obese, compared to 43% of the total cohort, which was comprised of more than 3 million adults treated at hospitals during the same period.

“There are many different risk factors for Covid-19 severity, including age and other underlying conditions,” Kompaniyets told BreakingMED. The mounting evidence linking increasing BMI to poorer Covid-19 outcomes is just one more reason to address obesity at the public health level, she added.

“Increased medical care policies are also needed, including reimbursement for obesity treatment services such as access to registered dietitians and medication,” she said.

Study co-author Alyson Goodman, MD, of the CDC’s Division of Nutrition, Physical Activity and Obesity, added that the latest findings have implications for clinicians treating patients with Covid-19.

“It is important to take obesity into account when considering a care plan,” she told BreakingMED, adding that clinicians need to know obesity is a strong risk factor for disease escalation and poor outcomes, especially in combination with certain comorbidities.

The study included data from the large hospital-based, all-payer database PHD-SR, which includes close to 800 U.S. hospitals. A total of 238 hospitals included data on patient height and weight and were included in the CDC study.

The sample included patients age ≥18 years with confirmed Covid-19 and measured height and weight treated at emergency departments or as inpatients.

Among the main findings:

  • Obesity was a risk factor for both hospitalization and death, exhibiting a dose-response relationship with increasing BMI category: adjusted relative risk (aRRs) for hospitalization ranged from 1.07 (95% CI, 1.05-1.09]) for patients with a BMI of 30–34.9 kg/m2 to 1.33 (95% CI, 1.30–1.37) for patients with a BMI ≥45 kg/m2 compared with those with a BMI of 18.5–24.9 kg/m2 (healthy weight).
  • Adjusted relative risk for death ranged from 1.08 (95% CI, 1.02–1.14) among those with a BMI of 30–34.9 kg/m2 to 1.61 (95% CI = 1.47–1.76) among those with a BMI ≥45 kg/m2.
  • Severe obesity was associated with ICU admission, with aRRs of 1.06 (95% CI, 1.03–1.10) for patients with a BMI of 40–44.9 kg/m2 and 1.16 (95% CI, 1.11–1.20) for those with a BMI ≥45 kg/m2.
  • Overweight and obesity were risk factors for invasive mechanical ventilation, with aRRs ranging from 1.12 (95% CI = 1.05–1.19) for a BMI of 25–29.9 kg/m2 to 2.08 (95% CI, 1.89–2.29) or a BMI ≥45 kg/m2.
  • Underweight patients had a 20% (95% CI, 16%–25%) higher risk for hospitalization than healthy weight patients. Patients aged <65 years who were underweight were 41% (95% CI = 31%–52%) more likely to be hospitalized than were those with a healthy weight.

“Continued strategies are needed to ensure community access to nutrition and physical activity opportunities that promote and support a healthy BMI,” the researchers concluded. “Preventing Covid-19 in adults with higher BMIs and their close contacts remains important and includes multifaceted protection measures such as masking, as well as continued vaccine prioritization and outreach for this population.”

  1. Obesity was a risk factor for hospitalization and death, especially among adults older than 65 years of age, with severe obesity (BMI ≥45) associated with a 61% increased risk for death.
  2. Hospitalization risk was 33% higher among patients with BMIs greater than 45 kg/m2, compared to the reference group of patients with BMIs between 18.5 and 24.9 kg/m2.

Salynn Boyles, Contributing Writer, BreakingMED™

This resarch was funded by the U.S. Centers for Disease Control and Prevention. Researcher John House reported employment with Premier, Inc. No other potential conflicts of interest were disclosed.

 

Cat ID: 125

Topic ID: 79,125,730,933,125,926,518,927,151,928,917,934