COVID-Related Decline in Acute CV Hospitalizations Sustained Through 2021

There was no big rebound in hospitalizations for acute cardiovascular conditions following initial dramatic declines in the first few months of the COVID-19 pandemic, at least through the end of 2021, according to an analysis out of New England.

In fact, hospitalizations for MI, congestive heart failure, angina, stroke, and TIA all tended to be less common in December 2021 than would have been expected based on prepandemic trends, although not all of the differences were statistically significant.

“That was surprising to us,” J. Franklin Wharam, MD (Duke University, Durham, NC), the study’s lead author, told TCTMD. He noted that the study was not designed to delve into the reasons underlying these trends, but speculated that several factors could be at play: patients avoiding the healthcare system due to fears of being infected with SARS-CoV-2, COVID-19 disproportionately killing high-risk individuals before they could have a CV event, or a possible decline in overdiagnosis due to declining numbers of hospitalizations, among others.

“I think in general there’s probably contributions from several of those and the contributions might differ by the particular cardiovascular event we studied,” Wharam said.

He and his colleagues report their findings in a research letter published in the January 2024 issue of JAMA Health Forum.

It’s very reasonable to be concerned that there could be an increase in cardiovascular events above what’s expected. J. Franklin Wharam

Commenting for TCTMD, Rishi Wadhera, MD (Beth Israel Deaconess Medical Center, Boston, MA), who wrote an editorial accompanying the study, said the finding of sustained lower-than-expected rates of CV hospitalizations through the end of 2021 “is not good news because this suggests that even a year into the pandemic, people that needed care weren’t getting it.”

And that provides a lesson for handling COVID-19 and future public health emergencies, he added. “In the clinical community, we need to do our part to make sure the patients who need to see us—whether that be in outpatient clinic or in the hospital—come in to see us,” he said. “We’re going to have to intensity our efforts to screen for, diagnose, and treat cardiometabolic risk factors due in part to the disruptions in care that many individuals experienced during the early phase of the pandemic.”

Tracking CV Hospital Stays in the Pandemic

In the early phase of the COVID-19 pandemic, the medical community recognized dramatic reductions in the numbers of patients presenting with various acute conditions, including MI, stroke, and others, that occurred in the context of public health measures aimed at blunting the impact of the virus. There has been concern that if this decline was largely driven by patients avoiding hospitals and doctors’ offices due to fears of infection, and not getting needed care for their risk factors or cardiac symptoms, it could lead to an eventual surge in CV hospitalizations later on.

To explore this issue, Wharam et al examined administrative claims data from Harvard Pilgrim Health Care, which insures about 1 million individuals. The analysis included people ages 35 and older living in Connecticut, Maine, Massachusetts, or New Hampshire who were covered by either commercial insurance or Medicare Advantage between March 2017 and December 2021.

Even a year into the pandemic, people that needed care weren’t getting it. Rishi Wadhera

The investigators measured MI and stroke hospitalizations, as well as cases of congestive heart failure, angina, and TIA that presented to the emergency department, observation unit, or hospital. Together, these conditions formed a composite high-acuity CV event outcome.

As observed in prior studies, there was a sharp decrease in the rate of composite events at the onset of the pandemic, with a relative 26.6% drop by April 2020 compared with what would have been expected based on prepandemic trends; declines for the individual events ranged from 26.1% to 27.8%.

For the combined events, rates remained lower than expected in March 2021 (by 9.6%) and December 2021 (by 19.8%).

Rates started to climb back up after the initial fall for all individual events, but—in general—did not reach expected levels by the end of 2021. They remained numerically lower in December 2021 for all outcomes, although the differences for MI and TIA (about 10% lower than expected) were not statistically significant.

“Factors explaining these trends could include lack of patient presentation during the 21-month follow-up, cardiovascular deaths outside the medical system, COVID-19–related deaths of people at risk for high-acuity CV events, decrease in overdiagnosis due to lower emergency department and hospital volumes, heart failure management at home, and reductions in adverse events,” Wharam et al write. “Further studies are needed to identify and quantify such factors.”

Potential for ‘Devastating Consequences’

In looking for reasons to explain the observed trends, and the lack of a full rebound in CV hospitalization rates, Wadhera also pointed to the possibility that patients remained fearful of becoming infected if they went to the hospital or a doctor’s office even after the initial months of the pandemic. There’s also the potential for survivorship bias—ie, the patients at highest risk for having a CV event died of COVID-19 first. In addition, he said, it’s possible that some patients lost touch with their regular physicians, making it less likely that they’d seek care at a hospital.

It will be important to extend these data out for more years to see what happens over the longer term, Wadhera said. “It was clear even through the early months of 2023 that many patients still feared coming into the hospital, and so I would not be surprised if this analysis were extended through the end of 2022 and early 2023 if we still saw persistently lower rates of cardiovascular hospitalizations even 2 years out into the pandemic than would be predicted.”

Asked about the longer-term outlook, Wadhera predicted that the disruptions to CV care and poorer management of risk factors that occurred during the pandemic will have lasting detrimental effects.

“I think all of those things together—changes in screening patterns, changes in treatment patterns, avoidance of healthcare for acute cardiovascular conditions—could have devastating consequences for the burden of cardiometabolic risk factors and cardiovascular diseases over the next 5 or 10 years,” he predicted.

Based on his clinical experience, Wharam agreed that in the coming years, “it’s very reasonable to be concerned that there could be an increase in cardiovascular events above what’s expected.”