COVID Death Rate Declining
A variety of factors have led to better survival chances for those hospitalized with the disease.
Under the headline “Studies Point To Big Drop In COVID-19 Death Rates,” NPR‘s All Things Considered slowly teases two medical studies of those hospitalized with the novel coronavirus.
Two new peer-reviewed studies are showing a sharp drop in mortality among hospitalized COVID-19 patients. The drop is seen in all groups, including older patients and those with underlying conditions, suggesting that physicians are getting better at helping patients survive their illness.
“We find that the death rate has gone down substantially,” says Leora Horwitz, a doctor who studies population health at New York University’s Grossman School of Medicine and an author on one of the studies, which looked at thousands of patients from March to August.
The study, which was of a single health system, finds that mortality has dropped among hospitalized patients by 18 percentage points since the pandemic began. Patients in the study had a 25.6% chance of dying at the start of the pandemic; they now have a 7.6% chance.
That’s a big improvement, but 7.6% is still a high risk compared with other diseases, and Horwitz and other researchers caution that COVID-19 remains dangerous.
The death rate “is still higher than many infectious diseases, including the flu,” Horwitz says. And those who recover can suffer complications for months or even longer. “It still has the potential to be very harmful in terms of long-term consequences for many people.”
So, a rather massive drop in fatality rate is good news. But . . . why is it happening? What’s the intervening variable? There’s been no revolutionary advance in treatment reported in the news. Are people going in earlier? Are fewer going in at a time, thus not being triaged?
Studying changes in death rate is tricky because although the overall U.S. death rate for COVID-19 seems to be dropping, the drop coincides with a change in whom the disease is sickening.
“The people who are getting hospitalized now tend to be much younger, tend to have fewer other diseases and tend to be less frail than people who were hospitalized in the early days of the epidemic,” Horwitz says.
So . . . fewer people are dying because we’ve already killed off the oldest, sickest people in the first wave? Well, not so fast.
So have death rates dropped because of improvements in treatments? Or is it because of the change in who’s getting sick?
To find out, Horwitz and her colleagues looked at more than 5,000 hospitalizations in the NYU Langone Health system between March and August. They adjusted for factors including age and other diseases, such as diabetes, to rule out the possibility that the numbers had dropped only because younger, healthier people were getting diagnosed. They found that death rates dropped for all groups, even older patients by 18 percentage points on average.
So, great. But what has changed? If it’s a function of the medical establishment being better at treating those who are sick, presumably there’s some specific treatment, technique, or such that can be isolated?
Mateen says drops are clear across ages, underlying conditions and racial groups. Although the paper does not provide adjusted mortality statistics, his rough estimates are comparable to those Horwitz and her team found in New York.
“Clearly, there’s been something [that’s] gone on that’s improved the risk of individuals who go into these settings with COVID-19,” he says.
Horwitz and others believemany things have led to the drop in the death rate. “All of the above is often the right answer in medicine, and I think that’s the case here, too,” she says.
Okay. So, what alls are above?
Doctors around the country say that they’re doing a lot of things differently in the fight against COVID-19 and that treatment is improving. “In March and April, you got put on a breathing machine, and we asked your family if they wanted to enroll you into some different trials we were participating in, and we hoped for the best,” says Khalilah Gates, a critical care pulmonologist at Northwestern Memorial Hospital in Chicago. “Six plus months into this, we kind of have a rhythm, and so it has become an everyday standard patient for us at this point in time.”
So . . . there is now some kind of “rhythm.”
Were we killing patients in the early cycles by making them guinea pigs in the various clinical trials and we’ve stopped that?
Is there some intervention that we were doing on Day 3 that we’re now doing on Day 1?
Or, again, could it be a capacity issue? These studies were done in New York. Were they simply overwhelmed in the first wave and not able to give each patient as much attention as they’re now getting?
Doctors have gotten better at quickly recognizing when COVID-19 patients are at risk of experiencing blood clots or debilitating “cytokine storms,” where the body’s immune system turns on itself, says Amesh Adalja, an infectious disease, critical care and emergency medicine physician who works at the Johns Hopkins Center for Health Security.
He says that doctors have developed standardized treatments that have been promulgated by groups such as the Infectious Diseases Society of America.
“We know that when people are getting standardized treatment, it makes it much easier to deal with the complications that occur because you already have protocols in place,” Adalja says. “And that’s definitely what’s happened in many hospitals around the country.”
Aha! So, yes, they have indeed developed a routine of care that has been standardized. Essentially, the early patients were in fact guinea pigs and we learned from them what worked and what didn’t. (That’s not a criticism! That’s the harsh reality of a novel disease and getting better as we go is the best we can hope for.)
But Horwitz and Mateen say that factors outside of doctors’ control are also playing a role in driving down mortality. Horwitz believes that mask-wearing may be helping by reducing the initial dose of virus a person receives, thereby lessening the overall severity of illness for many patients.
That certainly stands to reason.
And Mateen says that his data strongly suggest that keeping hospitals below their maximum capacity also helps to increase survival rates. When cases surge and hospitals fill up, “staff are stretched, mistakes are made, it’s no one’s fault — it’s that the system isn’t built to operate near 100%,” he says.