As the nation anticipates the end of the Covid-19 public health emergency, new research is showing that some groups are still feeling the long-term impacts of the disease. In the year following infection, individuals who experience long Covid are at high risk for a range of adverse health outcomes, including a doubled risk of death, according to a new study published Friday in JAMA Health Forum.
The study examined insurance claims data for 13,435 adults with long Covid and 26,870 without Covid-19 during a 12-month follow-up period. Accounting for factors present prior to infection, the long Covid group experienced increased mortality, with 2.8% individuals with long Covid dying compared to 1.2% of those without long Covid.
Those with long Covid were also roughly two times more likely to experience cardiovascular events including arrhythmias, stroke, heart failure and coronary artery disease. Pulmonary conditions were also common. The risk of pulmonary embolism more than tripled while the risk of COPD and moderate or severe asthma nearly doubled for those with long Covid.
The study found that risks were greatest among individuals hospitalized within a month of a Covid infection.
“We know from published literature that long Covid can result in fatigue, headache and attention disorder,” said Dr. Andrea DeVries, Staff Vice President for Health Services Research at Elevance Health and the lead author of the study. “While those conditions are concerning, the results from this study point to even more worrisome outcomes that can severely impact quality and length of life for individuals with long Covid.”
The US Centers for Disease Control and Prevention defines long Covid as having new, returning, or ongoing health issues more than four weeks after onset of initial infection. According to research by the CDC, one in five Covid-19 survivors ages 18 to 64 and one in four survivors 65 years or older experience an ongoing health issue that might be attributable to Covid-19 infection.
Long Covid has been associated with more than 200 signs and symptoms and 50 health conditions. Experts say the health consequences can last from months to years.
“We can only measure out as far as the pandemic has been happening, but early evidence suggests that a large portion of people who experienced post-Covid condition are doing so more than two years after their initial infection, which is basically as long as it could be,” said Dr. Mark Czeisler who wrote a related editorial also published in JAMA Health Forum.
Research has shown that Covid reinfection substantially increases an individual’s risk of death, hospitalization, and health consequences from long Covid. For example, the risk of cardiovascular disorders increases from 1.6 with one infection, to 3.0 with two infections and 4.8 with three or more infections.
“It’s demonstrating that it’s not like you have Covid once and then if you don’t get acutely ill or you don’t develop long Covid from that first infection that the coast is clear,” said Czeisler, who was not involved in the study.
Other risk factors for long Covid include older age, being female, tobacco use, higher body mass index, and experiencing more symptoms during the acute Covid-19 illness. Being vaccinated prior to infection has been associated with a decreased risk of long Covid, according to previous research.
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The study authors say these findings call for continued efforts to prevent Covid-19 infections and enhanced health monitoring of individuals after an infection.
“The biggest takeaway is that long Covid is a health condition that we need to continue to study and take seriously,” said DeVries.