(CNN) Long Covid leaves some people with long-term symptoms, but it can be deadly, too. It played a part in at least 3,544 deaths in the United States in the first 30 months of the Covid-19 pandemic, a new report says.
The report is the first official attempt by the US Centers for Disease Control and Prevention's National Center for Health Statistics to quantify the number of long Covid deaths in the United States.
Some experts say this finding is probably a significant undercount, considering that up to 30% of people who get Covid-19 go on to have long-term symptoms, according to the CDC.
The research, published Wednesday, analyzed death certificates in the National Vital Statistics System from January 2020 through the end of June 2022.
The research was difficult because, unlike with diseases such as cancer or diabetes, the US did not have a specific disease code to track long Covid during that time period.
Not every doctor, medical examiner or coroner fills out a death certificate the same way, so the researchers had to create a program to scan more than a million death certificates for text. Because there is not one settled term to describe long Covid, they included several key terms in their search, including "chronic Covid," "long Covid" and "post COVID syndrome."
They found that long Covid deaths made up less than 0.3% of the 1,021,487 Covid-related deaths from January 2020 through June 2022. There were some common elements among those who died, as well.
The majority of people who died from long Covid were White, older and male.
Specifically, 78.5% of the deaths were among non-Hispanic White people. Non-Hispanic Black people made up 10.1% of the deaths, followed by Hispanic people at 7.8%.
The death rate was highest among non-Hispanic American Indian and Alaska Natives, at 14.8 per 100,000 people.
Covid-19 deaths have disproportionately been among people of color, CDC research shows, and the new report notes that more people who identify as Black or Hispanic may have died of the initial disease before they could even develop long Covid. This may account for some of the racial differences in the new findings.
Studies have also found that with more barriers to health care for people of color, some people who died may not have been able to see a doctor to get an official Covid diagnosis, so it wouldn't be recognized on a death certificate, the report said.
Adults 75 to 84 accounted for 28.8% of long Covid deaths, followed by people 85 and older at 28.1% and people between 65 and 74 years old at 21.5%, the report says. In general, it is much more common for older adults to die from Covid than younger populations, CDC data shows.
Men accounted for a slightly larger proportion of the deaths, at 51.5%, which fits with other studies finding that being male is associated with a relative risk of developing severe Covid that's 1.29 times the relative risk for women.
The new report had several limitations, including that the death numbers are still provisional and could change. Additionally, race is not always a reliable element on a death certificate, as studies have shown that thousands of Americans' race is misclassified on their certificates. And clinical guidance on what constitutes long Covid has changed over the course of the pandemic, so death certificates may not fully capture the condition.
The study is a good start, but it takes a "fairly myopic view" of death from long Covid, said Dr. David Putrino, director of rehabilitation innovation for Mount Sinai Health System.
"This is very clearly data from folks who got very sick, ended up at the hospital with sustained organ damage," said Putrino, who works closely with long Covid patients but was not involved in the new report.
He says the research misses a sizable number of people who may get long Covid and die as a result.
For instance, some people who are not hospitalized for an initial infection but get long Covid go on to develop heart problems, studies show. Long Covid would not necessarily be captured on those death certificates, Putrino said.
"We read every single day about people who have previously been healthy, get Covid, recover and then have a heart attack or stroke or pulmonary embolism," Putrino said.
This research may also miss people with long Covid who died by suicide; the condition probably wouldn't be listed on their death certificates.
"We currently know that suicidal thoughts, suicidal acts, suicidal ideation and completed suicides are occurring all around the country with folks who were previously healthy, had a less severe acute Covid infection but then went on to develop very severe post-acute sequelae," Putrino said.
He is encouraged that the CDC is looking at the issue of death from long Covid.
"But again, we're just going to continue to get these sorts of skewed records unless we educate physicians that there are many ways that long Covid can cause death, just like there are many ways long Covid can cause permanent disability," Putrino said.
"People have had their lives completely ruined by Covid, and so this incomplete data point really only captures a small part of the long Covid experience," he said. "There are more than one way to have your life taken away from you with long Covid. Death is only one of those ways."