COVID Patient Survival Falls When Local Area Has Higher Caseload: Study

WEDNESDAY, Dec. 23, 2020 (HealthDay News) -- "Flattening the curve" could be key to reducing deaths among people hospitalized with COVID-19, a new study of U.S. hospitals suggests.

Researchers found that COVID-19 patients' survival odds depended not only on their age and overall health. It also depended on the hospital and the surrounding community.

At hospitals in counties where the infection was spreading quickly, death rates were typically higher. But if community cases were lower, so were hospital death rates.

The study could not determine exactly why, said lead researcher Dr. David Asch, a professor of medicine at the University of Pennsylvania.

But he speculated that "hospital strain" could be the reason: The more COVID-19 cases in the community, the more people arriving at the hospital -- and the greater the burden on staff and resources.

"From the beginning, people have been hearing the phrase 'flatten the curve,'" Asch said. "And I think this study may be demonstrating the importance of that."

The phrase refers to slowing down the spread of COVID-19, so that hospitals are not swamped with patients all at once.

And now, as cases are soaring across the country, Asch said it's more important than ever for people to follow guidelines on social distancing, mask-wearing and other measures to slow the spread.

The findings, published online Dec. 22 in the journal JAMA Internal Medicine, are based on nearly 40,000 COVID-19 patients who were admitted to 955 hospitals across the United States through June 30.

The average death rate at those centers was nearly 12%, though it varied widely from one hospital to another. At the one-fifth of hospitals that were "best-performing," 9% of COVID-19 patients died, on average. At the one-fifth of hospitals with the worst performance, the death rate was almost 16%.

There was some good news. Over time, the study found, COVID-19 death rates dropped substantially in nearly all hospitals.

Compared with the early days of the pandemic (through April), death rates in May and June were 25% to 50% lower at most hospitals. In one-quarter, death rates fell by over 50%.

According to Asch, that could be partly due to experience. As doctors and nurses learned more about managing COVID-19, survival improved. Certain new treatments may have helped, too, Asch said: The corticosteroid dexamethasone, for example, has been shown to cut the risk of death in severely ill patients.

But again, hospitals varied in their degree of improvement. And the "biggest determinant," Asch said, was the spread of COVID-19 in the local area.

Hospital strain could well be a factor, agreed Dr. Bruce Y. Lee.

Lee, who was not involved in the study, is executive director of Public Health Informatics, Computational and Operations Research at CUNY Graduate School of Public Health and Health Policy in New York City.

Even if hospitals have gotten better at treating severe COVID-19, Lee noted, they can't operate at their best if they are overrun and out of ICU beds.

People do not necessarily see the connection between their own daily actions and the survival of others who fall severely ill with COVID-19, Lee said. But efforts to flatten the curve are vitally important.

And that will remain true for some time, Lee stressed -- even with the two COVID-19 vaccines being rolled out across the country.

"Vaccines are really important," he said. "But by no means do they mean we can stop social distancing and wearing masks."

There is some concern, Lee noted, that people will prematurely give up those efforts as the vaccination campaign continues.

Asch said that would be a mistake. "I'd hate to see people lowering their guard now," he said.

More information

The U.S. Centers for Disease Control and Prevention has more on preventing COVID-19.

SOURCES: David Asch, MD, director, Center for Health Care Innovation, and professor, medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia; Bruce Y. Lee, MD, MBA, professor, health policy and management, and executive director, Public Health Informatics, Computational, and Operations Research, CUNY Graduate School of Public Health and Health Policy, New York City; JAMA Internal Medicine, Dec. 22, 2020, online