A University of Washington study provides some of the first details of 21 critically ill patients with the coronavirus disease 2019 (COVID-19) in the United States, most of whom were linked to exposures at a nursing home at the center of the country’s COVID-19 outbreak early on in the global crisis.

The study shows high rates of mortality overall and poor health outcomes among patients requiring ventilation, as well as surprising rates of heart issues related to the virus. The research provides new insights for health care providers treating older adults and those with existing health conditions.

This case series, published March 19 in JAMA, includes patients, ages 43 to 92 years, who were admitted to the intensive care unit (ICU) at EvergreenHealth Medical Center between Feb. 20 and March 5. About 86% of patients had co-existing diseases or health conditions, with chronic kidney disease and congestive heart failure being the most common.

“The big take home message is that this group is at high risk for poor outcomes,” says lead author Matt Arentz, a doctoral student in the Department of Global Health at the UW Schools of Public Health and Medicine and a pulmonary and critical care physician at EvergreenHealth. “We need to do everything we can to prevent them from getting infected in the first place. That means staying home and following appropriate measures in hospitals. If they do get infected, the data suggest they are at higher risk of becoming more seriously ill.”

The study shows a mortality rate of 67%. Ventilation was required for 71% of patients and all in this sub-group developed acute respiratory distress syndrome (ARDS), a condition associated with pneumonia that results in fluid leaking into the lungs and limiting the body's ability to utilize oxygen. After three days on a ventilator, 53% of the sub-group only got sicker.

“The problem with this virus is that we have no treatment for it, so for individuals who need life support, the most we can do is support them while their immune systems battle the virus off,” Arentz says. “The lack of effective treatments mean they are likely to stay on the ventilator for a long period of time.”

When patients need to be on a ventilator for 14 days or more, that not only presents a serious resource limitation but it also puts them at risk for additional health complications. “The longer they’re in the ICU, the more those risks become a reality,” Arentz adds.

Of the original 21 patients, seven had developed cardiomyopathy, a disease of the heart muscle that makes it harder for the heart to pump blood to the rest of the body. “A third of patients in this case series had evidence of heart issues that we presume were related to the infection. About half of these events were in patients with no history of heart disease,” Arentz says.

According to the study, it is unclear whether the high rate of heart issues in this case series reflects a direct cardiac complication of novel coronavirus infection or resulted from overwhelming critical illness. Arentz says, “The only way to know for sure is to do an autopsy.” Other researchers have described cardiomyopathy in COVID-19, including one study from the University of Texas Health Science Center at Houston, and further research may better characterize this risk.

When patients presented at the hospital, 76% had shortness of breath, 52% had a fever and 48% had a cough. Most of them developed symptoms 3.5 days before presenting to the hospital. Arentz points out that, based on this data, not having a fever is not a clear sign that the patient is in good health. “At the time when this study came out, everyone was stressing fever as a screening symptom for the coronavirus, but only 50% of patients had fevers. If we had ignored those without fever, we would have missed patients.”

Additionally, almost all 21 patients had an abnormal chest x-ray at admission. Initially, 52% of patients had x-rays showing bilateral reticular nodular opacities and 48% showing ground-glass opacities. By the third day, these rates increased to 86% and 67%, respectively.

What’s more, 67% of patients had lymphocyte counts that were very low despite total white blood cell counts being relatively normal. Lymphocytes are white blood cells responsible for fighting off a virus. “Further studies are needed, but it is possible that low lymphocyte counts could be a marker of poor outcomes,” Arentz says.

As of March 17, 23.5% of patients have remained critically ill and 9.5% have been discharged from the ICU at EvergreenHealth.