Cardiac arrests that happened outside of hospitals spiked in 2021, according to a new U.S. study.
Out-of-hospital cardiac arrests were higher after the COVID-19 pandemic than before the pandemic, U.S. researchers found.
They analyzed data from Seattle and King County in Washington state from the years 2018 to 2021. The dataset consisted of 13,081 patients, including 7,102 who were dead when emergency responders arrived and another 4,952 who were treated but died ahead of hospitalization or in the hospital.
Compared to the prepandemic years, or 2018 and 2019, there were 19 percent more people who suffered out-of-hospital cardiac arrests in the pandemic period, or 2020 and 2021, researchers said. That included a 10.8 percent increase in those who survived until responders arrived and a 27.2 percent increase in patients declared dead when responders reached the patients.
The increase in those who survived was among 18- to 64-year-olds, with the rate among those 65 and older holding steady.
The numbers were the highest during 2021, after the COVID-19 vaccines were rolled out.
The researchers did not factor in vaccination status, instead aiming to examine the impact of COVID-19 on out-of-hospital cardiac arrests.
Of the people who suffered out-of-hospital cardiac arrests during the pandemic and survived until emergency responders arrived, 6.2 percent tested positive for COVID-19 in the two weeks before the cardiac arrests or the week following the cardiac arrest, or were diagnosed with COVID-19. Just 3.7 percent of a random sample of those who were declared dead on arrival had COVID-19, which was lower than the percentage in a recent Maryland study.
During the pandemic, the Washington state researchers said, survival was less likely among people who suffered out-of-hospital cardiac arrests (OHCA), consistent with previous research. While 42.6 percent of people survived to hospital admission before the pandemic, just 35.7 percent did in 2020 and 2021. And compared to 2018 and 2019, when 19.2 percent of the patients survived to hospital discharge, just 15.4 percent of patients were discharged alive during the pandemic.
COVID-19 contributed to the downturn in survival, but only a little, the researchers said. They pegged it as responsible for 18.5 percent of the downturn.
The major factors, they said, included social isolation that led to fewer observed events, a delay in health care workers treating patients due to updated equipment and resuscitation protocols, and hampered emergency response times. The factors were described as Utstein characteristics.
"OHCA survival was poorer during the pandemic years, largely owing to changes in systemwide Utstein characteristics, as opposed to patient-specific acute SARS-CoV-2 infection," Jennifer Liu, an epidemiologist at the Seattle and King County Department of Public Health, and her coauthors wrote. SARS-CoV-2 causes COVID-19.
Other groups have also said that indirect reasons for the lowered survival rate and increased occurrence rate could stem from reasons such as delayed response times.
Ms. Liu and the other authors declared no conflicts of interest or funding.
Limitations of the paper, which was published by JAMA Network Open, include the data being from one county.
Vaccination Impact?
Ms. Liu did not respond to a request for comment, including why the group did not analyze the possible impact of vaccination on the increase in out-of-hospital cardiac arrests. The COVID-19 vaccines can cause myocarditis, or heart inflammation, as well as other cardiac events.
"What most striking is the lack of analysis of a possible correlation of OHCA case rates with the COVID-19 vaccination campaigns that started at the end of 2020 and continued throughout 2021," Retsef Levi, a professor of operations management at the Massachusetts Institute of Technology, told The Epoch Times via email.
"Such correlation has been observed in other studies and since the authors seem to have access to comprehensive case-level data (e.g., medical records), it looked like they could have potentially done that," Mr. Levi, who was not involved in the research, added. "At the very least the authors should have analyzed the temporal correlation between community vaccination rates and the OHCA case rates."
Mr. Levi noted that the number of events was primarily grouped in the pandemic and pre-pandemic periods, apart from one graph in the supplementary content, which showed the year with the most events was 2021.
"It is not even clear if there is an increase in 2020 compared to the baseline, or the entire increase is observed in 2021," Mr. Levi said.
The researchers did find a statistically significant correlation between weekly COVID-19 rates in the community and the weekly rate of OHCA, but only in 2020, not in 2021. Mr. Levi contributed to research that found the worse outcomes among people who suffered heart cardiac arrests during the pandemic in Boston stemmed from a reluctance to seek health care. He and other researchers also found that in Israel, increases in emergency calls for young people for cardiovascular events were significantly associated with COVID-19 vaccination.
Some other papers have found that prior to the vaccine rollout, people who tested positive for COVID-19 and suffered a cardiac arrest were more likely to die when compared to people who did not test positive.
