Doctors have been warning for months that “underlying conditions” raise your risk of getting hit hard with the coronavirus, based on the experience of other countries. But which conditions, and how much difference does each one make?

The first comprehensive U.S. numbers were published Tuesday afternoon, illustrating just how much worse the consequences of an infection can be for those with heart, lung, and kidney problems.

Hospitalization status was listed for 7,162 infected patients for whom medical histories were available, some of whom had more than one of the following conditions:

  • Among 784 patients with diabetes, half were hospitalized, including 148 (18.8%) in intensive care. That compares with 2.2% of those with no underlying conditions needing ICU treatment.
  • Among 656 patients with chronic lung disease, more than one-third were hospitalized, including 94 (14.3%) in intensive care.
  • For 647 infected people with heart disease, more than half were hospitalized, including 132 (20.4%) in intensive care.
  • For 213 infected people with kidney disease, two-thirds were hospitalized, including 56 (26.2%) in intensive care.

While the numbers represented the first large-scale description of hospitalized COVID-19 patients in the United States, the authors cautioned that the data were incomplete, and that the percentages would change.

Because of limited testing so far in many parts of the country, patients with severe symptoms were more likely to get tested, the authors wrote in Morbidity and Mortality Weekly Report, published by the U.S. Centers for Disease Control and Prevention.

“This analysis was limited by small numbers and missing data because of the burden placed on reporting health departments with rapidly rising case counts,” the study authors wrote.

For example, smokers with the coronavirus fared worse than nonsmokers, on average, with one-fourth of infected smokers going to the hospital. But that percentage was based on just 96 smokers who were identified for the study.

For most of the 122,000-plus U.S. patients who had been identified as of March 28 — the cutoff date used by the study authors — no smoking or other medical history was available yet. So the true percentages of those who ended up in a hospital with each underlying medical condition could be lower than what the authors reported.

Still, the data so far are consistent with results from China and other countries, as those without underlying medical conditions were more likely to fare better against the virus. The 7,162 patients in the U.S. study included 4,470 with no underlying illness or smoking history — of which just 404 (9%) were hospitalized, including 99 (2.2%) in intensive care.

The study authors did not calculate the percentages of various underlying conditions for patients who died as a result of infection, as the health history for many of them was not yet available.