More than 3,500 Americans died of long-COVID-related illness during the pandemic's first 2 ½ years, according to a new report published by the Centers for Disease Control and Prevention National Center for Health Statistics.

Long COVID lacks a specific definition, but generally covers signs, symptoms, and conditions that continue or develop after initial infection. The diagnosis often is associated with cognitive impairment, breathlessness, fatigue, and coughing.

Deaths associated with long COVID, and cited in the study released Wednesday by the CDC’s National Center for Health Statistics, represents 0.3% of the 1 million overall deaths from coronavirus.

Still, experts say the statistics show the danger of ignoring lingering symptoms.

"A lot of people think of long COVID as associated with long-term illness," CDC health scientist and lead author of the study Farida Ahmad said, The Washington Post reported.

"This shows it can be a cause of death."

Some of the study's statistics surrounding long COVID from Jan. 1, 2020, through June 30, 2022 surrounding long COVID showed:

• Women are more likely than men to develop long COVID, but men accounted for a slightly higher percentage of long-COVID deaths.
• A large portion (30%) of the long-COVID deaths occurred in adults between 75 and 84 years old, followed by adults 85 and older.
• Almost 80% of long-COVID deaths occurred among non-Hispanic whites.
• The death rate was highest among American Indian and Alaska Native people — 15 in every 100,000 people — and lowest among Asians.

"This is yet another piece of evidence that long COVID can be fatal," said Ziyad Al-Aly, a clinical epidemiologist at Washington University and chief of research and development at VA St. Louis Health Care System, the Post reported.

"Lets not trivialize it or say it’s all in people’s heads."

The study's authors and other experts cautioned that the report might have undercounted the number of deaths because the deaths were identified from information entered on death certificates in the National Vital Statistics System.

"Death certificate data is fraught with uncertainty and ambiguity, something acknowledged by the CDC," said Francesca Beaudoin, head of the Brown University School of Public Health’s Long Covid Initiative, the Post reported.

Such problems are compounded with long COVID because there are varied definitions and terminology. In fact, there was no diagnostic code for long COVID until October 2021.

The CDC says that as many as 1 in 13 U.S. adults are experiencing symptoms that last three or more months after contracting COVID.

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