Covid hospitalizations – the most common metric when discussing the seriousness of the pandemic – may not be as meaningful of a number as many once thought.
A brand new study is calling into question how reliable and meaningful of a number of “patients hospitalized with Covid-19” in the U.S. is.
Covid hospitalizations – the most common metric heard when discussing the seriousness of the pandemic – may not be nearly as meaningful of a number as many once thought. And don’t take it from us: The Atlantic published a stunning piece on Tuesday citing a new study that suggests “almost half of those hospitalized with COVID-19 have mild or asymptomatic cases”.
The Atlantic had formerly called Covid hospitalizations “the most reliable pandemic number,” last winter. Now, after a nationwide study of hospitalization records was release, the publication is walking back its fervor on that statement.
Researchers from Harvard Medical School, Tufts Medical Center, and the Veterans Affairs Healthcare System took on the task of trying to figure out how serious Covid cases were in those hospitalized, and how many people counted as Covid hospitalizations were actually in the hospital for Covid, versus getting a Covid test after being admitted for something else.
The study “analyzed the electronic records for nearly 50,000 COVID hospital admissions at the more than 100 VA hospitals across the country,” The Atlantic wrote. It “checked to see whether each patient required supplemental oxygen or had a blood oxygen level below 94 percent” in order to try and determine if cases met the NIH’s threshold for “severe COVID”.
What the study found was that from March 2020 to January 2021, 36% of Covid cases in the hospital were mild or asymptomatic. From January 2021 to June 2021, during the Delta variant’s spread, that number rose all the way to 48%. For vaccinated hospital patients, the number rose to a stunning 57%.
As The Atlantic put it in their own words: “The study suggests that roughly half of all the hospitalized patients showing up on COVID-data dashboards in 2021 may have been admitted for another reason entirely, or had only a mild presentation of disease.”
The limitations of the study obviously included the fact that the VA isn’t representative of the total U.S. population:
Among the limitations of the study is that patients in the VA system are not representative of the U.S. population as a whole, as they include few women and no children. (Still, the new findings echo those from the two pediatric-admissions studies.) Also, like many medical centers, the VA has a policy to test every inpatient for COVID, but this is not a universal practice. Lastly, most of the data—even from the patients admitted in 2021—derive from the phase of the pandemic before Delta became widespread, and it’s possible that the ratios have changed in recent months. The study did run through June 30, however, when the Delta wave was about to break, and it did not find that the proportion of patients with moderate to severe respiratory distress was trending upward at the end of the observation period.
Graham Snyder, the medical director of infection prevention and hospital epidemiology at the University of Pittsburgh Medical Center, says the study buries the lede of how effective the vaccine is: “It’s underreported how well the vaccine makes your life better, how much less sick you are likely to be, and less sick even if hospitalized. That’s the gem in this study.”
Daniel Griffin, an infectious-disease specialist at Columbia University, concurred: “People ask me, ‘Why am I getting vaccinated if I just end up in the hospital anyway?’ But I say, ‘You’ll end up leaving the hospital.’”
“We should refine the definition of hospitalization,” said Shira Doron, an infectious-disease physician and hospital epidemiologist at Tufts Medical Center and co-author of the study. “Those patients who are there with rather than from COVID don’t belong in the metric.”
What does the study as a whole conclude? Again, in the words of The Atlantic: “…the study also demonstrates that hospitalization rates for COVID, as cited by journalists and policy makers, can be misleading, if not considered carefully.”