COVID-19 and Underlying Conditions, Early 2020: CDC's First Look at U.S. Patients

On March 11, 2020, the World Health Organization declared COVID-19 a pandemic. By March 28, 571,678 confirmed cases and 26,494 deaths had been reported worldwide. Reports from China and Italy suggested that older age and underlying health conditions raised the risk of severe disease, and older U.S. adults — 65 and older, especially 85 and older — also appeared at higher risk. But nothing had yet been published on the underlying conditions of U.S. patients.

This early CDC report, posted as an Early Release on March 31, 2020, was the first look.

The data

• Cases: laboratory-confirmed COVID-19 reported to CDC from 50 states, four territories and affiliated islands, the District of Columbia, and New York City, with illness beginning February 12–March 28, 2020. People repatriated from Wuhan and the Diamond Princess cruise ship were excluded.
• Missing onset dates were estimated as 4 days before the first specimen — the median gap in cases with known dates.
• Conditions asked about (yes, no or unknown): chronic lung disease (asthma, COPD, emphysema), diabetes, cardiovascular disease, chronic kidney disease, chronic liver disease, an immunocompromised condition, neurologic or neurodevelopmental disorders and intellectual disability, pregnancy, current or former smoking, and other chronic disease.
• The data were preliminary and incomplete, so the analysis was descriptive, with no statistical comparisons.

What was reported

By March 28, CDC had 122,653 confirmed cases and 2,112 deaths. Case report forms came in for 74,439 (60.7%) — and only 7,162 (5.8%) said whether the patient had any underlying condition or risk factor.

Of those 7,162, 2,692 (37.6%) had at least one; 4,470 (62.4%) had none reported.

The most common conditions:

Daily reported COVID-19 cases in the United States, February 12–March 28, 2020. Figure from CDC's report.

Adults, with and without conditions

For adults 19 and older — children were left out of this part because only 32 with conditions were reported — the share hospitalized was given as a range, to allow for missing data:

Few patients under 19 were hospitalized (48) or admitted to an ICU (8). Among all patients with complete information, 184 died — all aged 19 or older — and 173 (94%) had at least one underlying condition.

What it meant

The findings matched China and Italy: people with conditions such as diabetes, high blood pressure, COPD, coronary artery disease, cerebrovascular disease, chronic kidney disease and smoking may face a higher risk of severe disease or death. It was not yet known whether how severe or well controlled a condition is changes that risk.

These conditions are common in the United States:

• diagnosed diabetes: 10.1% of adults (self-reported, 2018);
• heart disease of all types (excluding high blood pressure alone): 10.6%, age-adjusted (2017);
• COPD: 5.9% of adults, age-adjusted;
• current asthma: 7.9% of people of all ages (2018).

What CDC advised:

• People with underlying conditions who develop fever, cough or shortness of breath should contact their health care provider immediately.
• They should wash their hands, clean and disinfect high-touch surfaces, and keep their distance — stay home, avoid crowds, gatherings and travel, and avoid sick people.
• They should keep at least a 30-day supply of medication, a 2-week supply of food and other necessities, and know the symptoms.
• Everyone who is ill should stay home except to get medical care, not go to work, and keep away from others — especially people who work with those at high risk.
• Community mitigation to slow the spread protects everyone, especially those at higher risk.

Limits

• Data on conditions existed for only 5.8% of cases, and those with missing information may differ.
• Short follow-up may understate outcomes.
• Limited testing likely skewed the cases toward the more severe.
• Risk could not be compared between people with and without conditions.
• Umbrella categories — asthma and COPD together, for example — hid differences.
• Too few severe outcomes were reported for neurologic disorders, liver disease, current smoking and pregnancy to draw conclusions.

Sources

Based on CDC COVID-19 Response Team, "Preliminary Estimates of the Prevalence of Selected Underlying Health Conditions Among Patients with Coronavirus Disease 2019 — United States, February 12–March 28, 2020," MMWR Morbidity and Mortality Weekly Report, volume 69, Centers for Disease Control and Prevention; a work of the United States government in the public domain.