One of the things I have wondered about for some time is the relationship between morbidity and mortality due to COVID-19 and obesity. Apparently, I’m not the only one who has been thinking about that as this CDC report confirms:
Among 3,242,649 patients aged ≥18 years with documented height and weight who received ED or inpatient care in 2020, a total of 148,494 (4.6%) had ICD-10-CM codes indicating a diagnosis of COVID-19 (Table). Among 71,491 patients hospitalized with COVID-19 (48.1% of all COVID-19 patients), 34,896 (48.8%) required ICU admission, 9,525 (13.3%) required invasive mechanical ventilation, and 8,348 (11.7%) died. Approximately 1.8% of patients had underweight, 28.3% had overweight, and 50.8% had obesity. Compared with the total PHD-SR cohort, patients with COVID-19–associated illness were older (median age of 55 years versus 49 years) and had a higher crude prevalence of obesity (50.8% versus 43.1%).
Obesity was a risk factor for both hospitalization and death, exhibiting a dose-response relationship with increasing BMI category: aRRs for hospitalization ranged from 1.07 (95% confidence interval [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 (Figure 1) compared with those with a BMI of 18.5–24.9 kg/m2 (healthy weight); aRRs for death ranged from 1.08 (95% CI = 1.02–1.14) for those with a BMI of 30–34.9 kg/m2 to 1.61 (95% CI = 1.47–1.76) for 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) for a BMI ≥45 kg/m2. Associations with risk for hospitalization and death were pronounced among adults aged <65 years: aRRs for patients in the highest BMI category (≥45 kg/m2) compared with patients with healthy weights were 1.59 (95% CI = 1.52–1.67) for hospitalization and 2.01 (95% CI = 1.72–2.35) for death.
Criticisms of “fat-shaming” upset me. Social sanction can be a powerful force in regulating behavior and of the factors involved in obesity which include behavior, heredity, and acquired factors only tangentially related to behavior, is the easiest to address.
“BMI is continuous in nature, and the analyses in this report describe a J-shaped association between BMI and severe COVID-19, with the lowest risk at BMIs near the threshold between healthy weight and overweight in most instances.”
I suspect this is true for most health risks. The main health risk from being overweight is that it can lead to obesity.
No argument here. Although I have reservations about using BMI as a gauge for distinguishing among healthy weight, overweight, and obesity. It’s fine for the mythical average individual.