The coronavirus pandemic has forced doctors to make difficult decisions about which patients get immediate medical care.
In New York City, where more than 38,000 cases have been reported, hospitals are reserving tests for patients with severe illnesses, while people with mild cases — which can still be painful and long-lasting — have been told to stay home. But doctors still know very little about the symptoms that serve as warning signs of a severe case of COVID-19.
A new study from researchers at New York University used predictive analytics to determine the early signs of severe lung disease among COVID-19 patients. The researchers determined that three symptoms, taken together, were strong predictors of acute respiratory distress syndrome, a life-threatening lung injury that might require a patient to be intubated.
The first factor was a slight increase in ALT, an enzyme that can signal the presence of liver damage or inflammation. The second was deep muscle aches, known clinically as myalgia. The third was higher levels of hemoglobin, a protein that transports oxygen through the blood.
“Our hope is to assist doctors in that first stage to be able to identify who may become sick of the many mild cases,” Megan Coffee, an infectious-disease clinician and lead author of the study, told Business Insider.
The study analyzed records from 53 hospitalized patients in Wenzhou, China. Most were in their 30s or 40s, and nearly two-thirds were men.
While typical symptoms of COVID-19 include a fever, a dry cough, and difficulty breathing, body aches are the next most common symptom, according to the World Health Organization; the agency reported in February that about 15% of coronavirus patients experienced body aches or joint pain.
Coffee said that as a clinician, she’s now paying more attention to patients who show these symptoms — but that all three must be present for someone to have an early risk of severe lung disease.
Flagging severe cases could lower emergency visits
On their own, the three mild symptoms don’t normally set off alarm bells for clinicians, Coffee said.
“Body aches wouldn’t be the first thing that I would ask about,” she said. “I would of course always ask about shortness of breath before anything, because that’s somebody who has to be immediately helped.”
But determining whether a patient is likely to get worse could help hospitals decide which cases to monitor.
Health workers inside a tent constructed to test people for COVID-19 outside the Brooklyn Hospital Center in New York City. REUTERS/Andrew Kelly
“Hospitals are just so overstretched that if someone doesn’t immediately need oxygen they may not be able to find a place for them,” Coffee said. “But they might be able to say, ‘You really need to check back in tomorrow.'”
Doctors could then treat a patient before their case becomes critical, lessening the burden on emergency rooms.
“We’re not by any means trying to replace doctors’ decisions,” Anasse Bari, a clinical assistant professor at NYU who coauthored the study, told Business Insider. “We just want to arm doctors with tools to see quickly if this is a severe case and predict outcomes.”
Patients with severe lung disease saw symptoms worsen after 5 to 8 days
On average, patients in the NYU study were admitted to the hospital three days after their symptoms started.
Most had a fever and a dry cough, though about a third developed a wet cough. Less than a quarter were wheezing or had difficulty breathing. Only a few had body aches, a sore throat, or diarrhea.
The study found that most patients developed mild symptoms at first. In severe cases, symptoms like shortness of breath, pneumonia, and ARDS typically appeared five to eight days into the illness.
A nasal ventilator at a pulmonology hospital in Vannes, France. Reuters/Stephane Mahe
About 88% of patients had white patches, called “ground glass,” on their CT scans, signaling the presence of fluid in their lungs.
But only five — all men — developed severe lung disease.
Upon arriving at the hospital, the men displayed a fever, a cough, wheezing, and shortness of breath. Each one also had ground glass on his CT scan.
Older men are more likely to develop deadly cases, but age and gender weren’t strong predictors of severe lung disease
Data from China, South Korea, and Italy suggests that more men than women are dying of COVID-19. One possible explanation is that men report higher rates of smoking. Men also have higher rates of preexisting conditions such as high blood pressure and diabetes.
But the NYU researchers determined that gender wasn’t a strong predictor of severe lung disease.
“Even though everyone who had ARDS was male, most of the men in the study did not develop ARDS,” Coffee said.
The researchers also found that age wasn’t a strong warning sign either, even though the COVID-19 death rate is significantly higher among older people.
But the predictions could change depending on where the patients are.
“As soon as we get data from the US, we’ll be able to rerun the model and see if we learn something else,” Bari said. “We hope that we will start collaborating very soon with hospitals in New York City.”