Nearly half, or 47 percent, of U.S. adults have one of five underlying medical conditions associated with increased risk for severe COVID-19–associated illness, the Centers for Disease Control and Prevention (CDC) reported in its Morbidity and Mortality Weekly Report.
The agency estimated disease risk for 3,142 U.S. counties.
Counties with the highest prevalence were concentrated in the Southeast and Appalachian region. The estimated number of people with these conditions followed population distributions, but prevalence was higher in more rural counties.
According to numerous previous studies, the risk for severe COVID-19–associated illness (illness requiring hospitalization, admission to an intensive care unit (ICU), mechanical ventilation, or resulting in death) increases with age, as well as the presence of underlying medical conditions, including chronic obstructive pulmonary disease (COPD), cardiovascular disease, diabetes, chronic kidney disease, and obesity, the CDC said.
The overall weighted prevalence of these conditions was 30.9 percent for obesity, 11.4 percent for diabetes, 6.9 percent for COPD, 6.8 percent for heart disease, and 3.1 percent for chronic kidney disease. Counties with the highest prevalence of any condition were concentrated in Southeastern states, particularly in Alabama, Arkansas, Kentucky, Louisiana, Mississippi, Tennessee, and West Virginia, as well as some counties in Oklahoma, South Dakota, Texas, and northern Michigan, among others.
The estimated median prevalence of any condition generally increased as the location became more rural, ranging from 39.4 percent in large central metropolitan counties to 48.8 percent in non-core counties, while the estimated median number of people with any underlying condition ranged from 4,300 in non-core counties to almost 302,000 in large central metropolitan counties.
To reach these findings, the CDC used a small-area estimation approach to determine county-level prevalence of selected conditions associated with severe COVID-19 disease among U.S. adults aged 18 years and older using self-reported data from the 2018 Behavioral Risk Factor Surveillance System (BRFSS), as well as population data from the U.S. Census. BRFSS is an annual, random-digit–dialed landline and mobile telephone survey of U.S. adults aged 18 years and older. Overall, 437,500 people participated in the 2018 BRFSS survey.
