Long COVID has caused or contributed to at least 3,500 deaths in the United States, an analysis of death certificates by the Centers for Disease Control and Prevention found.
The study, published Wednesday, is believed to be the first nationwide examination of whether long COVID or related terms appear in official American death records. While it found that such phrases were recorded in only a tiny proportion of the more than 1 million deaths tied to infection with the coronavirus, the researchers and other experts said the results added to growing recognition of how serious long-term post-COVID medical problems can be.
"It's not one of the leading causes of death, but, considering that this is the first time that we've looked at it and that long COVID is an illness that we're learning more about day after day, the major takeaway is that it is possible for somebody to die and for long COVID to have played a part in their death," said Farida Ahmad, a health scientist at the National Center for Health Statistics at the CDC who led the study.
Long COVID is a complex constellation of symptoms that can last for months or longer and can affect virtually every organ system. Some of the most debilitating post-COVID symptoms are breathing problems, heart issues, extreme fatigue, and cognitive and neurological issues.
The researchers looked at death certificates in every state and Washington, D.C., dated from Jan. 1, 2020, to June 30, 2022. They found 1,021,487 certificates that included a diagnostic code for COVID-19 as an underlying or contributing cause of death. Of those, 3,544 — or 0.3% of the total — listed long COVID or terms such as post-COVID syndrome, chronic COVID or long-haul COVID.
Ahmad and experts not involved in the research said the number of deaths related to long COVID in the study was almost certainly an underestimate. It has taken time for the condition to be recognized and identified by doctors and other medical providers. And the study was not able to include a new diagnostic code for long COVID because it was not yet being used in reporting of deaths in the United States, the researchers said.
"This new research is important in raising a concern, but it should be followed with more definitive work," said Dr. Jeffrey Martin, chief of the division of clinical epidemiology in the department of epidemiology and biostatistics at the University of California, San Francisco, who was not involved in the research.
"Historically, death certificates have been incomplete in explaining how a person died," said Martin, who suggested that future research should include interviewing patients' doctors and family members and evaluating their medical records.