For patients hospitalized with chest pain, the amount of time they spend sedentary afterward is linked to a greater risk for more heart problems and death within a year. That’s the key finding of a new peer-reviewed study my colleagues and I published in the journal Circulation: Cardiovascular Quality and Outcomes.

We asked 609 emergency room patients experiencing chest pain — average age of 62 — to wear a physical activity monitor for 30 days after leaving the hospital. The monitor measured movements, sitting time and sleep throughout the day. We then followed patients for one year to track whether they had additional heart problems or died.

We found that patients who averaged more than 15 hours of sedentary behavior daily — which does not include sleep — were more than twice as likely to experience more heart problems or die in the year after discharge than patients who accrued a daily average of 12 hours of sedentary time.

But our goal wasn’t just to document that sitting is harmful. It was also to figure out what patients should do instead to lower their risk.

We found that replacing 30 minutes of sedentary time with moderate or vigorous movement, like brisk walking or running, was most beneficial. It was associated with a 62% lower risk of experiencing more heart problems or dying in the year after discharge. But we also found that replacing 30 minutes of sedentary time with just light movement, such as slow walking or housework, lowered the risk of heart problems and death by 50%.

Sleep was also a healthier option. Replacing 30 minutes of sedentary time with sleep lowered the risk of heart problems and death by 14%.

Why it matters

Over 8 million people in the U.S. are admitted to the hospital with chest pain suggestive of acute coronary syndrome. annually. This covers a range of conditions involving reduced blood flow to the heart, including angina and heart attack.

Patients with acute coronary syndrome remain at high risk of having another heart problem even with optimal medical treatment.

The risk also remains high for patients with chest pain who are discharged without a diagnosis of acute coronary syndrome, as their unexplained chest pain may be a precursor to more serious heart problems. Given this risk, there is a need to identify risk factors that can be modified to improve a patient’s prognosis after hospitalization for chest pain.

In previous research, we found that patients with acute coronary syndrome had a fear of exercise and were sedentary, spending over 13 hours a day sitting.

Given that sedentary behavior has been linked to poor heart health in the general population, we were concerned that patients were unknowingly increasing their risk of having another heart problem.

Our latest findings confirm that sedentary time is a harmful behavior for these patients. But beyond telling patients to stop sitting so much, our work provides important guidance: Any movement, regardless of how intense, can be beneficial after hospitalization. This is especially relevant for people recovering from heart problems who may find exercise difficult or scary.

While exercise provides the best “bang for your buck” in terms of health benefits, our findings are good news for patients who may not have the time, ability or desire to exercise. And for those unable to fit in more movement, just getting an extra half hour of sleep is a small, doable step that can make a meaningful difference for your health after hospitalization.

What still isn’t known

Researchers don’t fully understand why sedentary time is harmful. Muscles help regulate blood sugar and lipid levels. It is thought that when muscles aren’t used, such as when patients sit for hours, this can lead to harmful elevations in blood sugar and lipids.

In turn, this can cause inflammation, plaque buildup in the arteries and organ damage. More research is needed to understand the biological mechanisms so that we can determine just how much movement is needed in a day.

What’s next

While our study highlights the potential risks of sedentary behavior after being hospitalized for chest pain, it was an observational study. Clinical trials are needed to confirm that replacing sedentary time with activity or sleep can improve prognosis.

The Research Brief is a short take on interesting academic work.

Keith Diaz, Associate Professor of Behavioral Medicine, Columbia University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

On May 20, 2025, the Food and Drug Administration announced a new stance on who should receive the COVID-19 vaccine.

The agency said it would approve new versions of the vaccine only for adults 65 years of age and older as well as for people with one or more risk factors for severe COVID-19 outcomes. These risk factors include medical conditions such as asthma, cancer, chronic kidney disease, heart disease and diabetes.

However, healthy younger adults and children who fall outside of these groups may not be eligible to receive the COVID-19 shot this fall. Vaccine manufacturers will have to conduct clinical trials to demonstrate that the vaccine benefits low-risk groups.

FDA Commissioner Marty Makary and the agency’s head of vaccines, Vinay Prasad, described the new framework in an article published in the New England Journal of Medicine and in a public webcast.

The Conversation U.S. asked Libby Richards, a nursing professor involved in public health promotion, to explain why the changes were made and what they mean for the general public.

Why did the FDA diverge from past practice?

Until the May 20 announcement, getting a yearly COVID-19 vaccine was recommended for everyone ages 6 months and older, regardless of their health risk.

According to Makary and Prasad, the Food and Drug Administration is moving away from these universal recommendations and instead taking a risk-based approach based on its interpretation of public health trends – specifically, the declining COVID-19 booster uptake, a lack of strong evidence that repeated boosters improve health outcomes for healthy people and the fact that natural immunity from past COVID-19 infections is widespread.

The FDA states it wants to ensure the vaccine is backed by solid clinical trial data, especially for low-risk groups.

Was this a controversial decision or a clear consensus?

The FDA’s decision to adopt a risk-based framework for the COVID-19 vaccine aligns with the expected recommendations from the Advisory Committee on Immunization Practices, an advisory group of vaccine experts offering expert guidance to the Centers for Disease Control and Prevention on vaccine policy, which is scheduled to meet in June 2025. But while this advisory committee was also expected to recommend allowing low-risk people to get annual COVID-19 vaccines if they want to, the FDA’s policy will likely make that difficult.

Although the FDA states that its new policy aims to promote greater transparency and evidenced-based decision-making, the change is controversial – in part because it circumvents the usual process for evaluating vaccine recommendations. The FDA is enacting this policy change by limiting its approval of the vaccine to high-risk groups, and it is doing so without any new data supporting its decision. Usually, however, the FDA broadly approves a vaccine based on whether it is safe and effective, and decisions on who should be eligible to receive it are left to the CDC, which receives research-based guidance from the Advisory Committee on Immunization Practices.

Additionally, FDA officials point to Canada, Australia and some European countries that limit vaccine recommendations to older adults and other high-risk people as a model for its revised framework. But vaccine strategies vary widely, and this more conservative approach has not necessarily proven superior. Also, those countries have universal health care systems and have a track record of more equitable access to COVID-19 care and better COVID-19 outcomes.

Another question is how health officials’ positions on COVID-19 vaccines affect public perception. Makary and Prasad noted that COVID-19 vaccination campaigns may have actually eroded public trust in vaccination. But some vaccine experts have expressed concerns that limiting COVID-19 vaccine access might further fuel vaccine hesitancy because any barrier to vaccine access can reduce uptake and hinder efforts to achieve widespread immunity.

What conditions count as risk factors?

The New England Journal of Medicine article includes a lengthy list of conditions that increase the risk of severe COVID-19 and notes that about 100 million to 200 million people will fall into this category and will thus be eligible to get the vaccine.

Pregnancy is included. Some items on the list, however, are unclear. For example, the list includes asthma, but the data that asthma is a risk factor for severe COVID-19 is scant.

Also on the list is physical inactivity, which likely applies to a vast swath of Americans and is difficult to define. Studies have found links between regular physical activity and reduced risk of severe COVID-19 infection, but it’s unclear how health care providers will define and measure physical inactivity when assessing a patient’s eligibility for COVID-19 vaccines.

Most importantly, the list leaves out an important group – caregivers and household members of people at high risk of severe illness from COVID-19 infection. This omission leaves high-risk people more vulnerable to exposure to COVID-19 from healthy people they regularly interact with. Multiple countries the new framework refers to do include this group.

Why is the FDA requiring new clinical trials?

According to the FDA, the benefits of multiple doses of COVID-19 vaccines for healthy adults are currently unproven. It’s true that studies beyond the fourth vaccine dose are scarce. However, multiple studies have demonstrated that the vaccine is effective at preventing the risk of severe COVID-19 infection, hospitalization and death in low-risk adults and children. Receiving multiple doses of COVID-19 vaccines has also been shown to reduce the risk of long COVID.

The FDA is requiring vaccine manufactures to conduct additional large randomized clinical trials to further evaluate the safety and effectiveness of COVID-19 boosters for healthy adults and children. These trials will primarily test whether the vaccines prevent symptomatic infections, and secondarily whether they prevent hospitalization and death. Such trials are more complex, costly and time-consuming than the more common approach of testing for immunological response.

This requirement will likely delay both the timeliness and the availability of COVID-19 vaccine boosters and slow public health decision-making.

Will low-risk people be able to get a COVID-19 shot?

Not automatically. Under the new FDA framework, healthy adults who wish to receive the fall COVID-19 vaccine will face obstacles. Health care providers can administer vaccines “off-label”, but insurance coverage is widely based on FDA recommendations. The new, narrower FDA approval will likely reduce both access to COVID-19 vaccines for the general public and insurance coverage for COVID-19 vaccines.

The FDA’s focus on individual risks and benefits may overlook broader public health benefits. Communities with higher vaccination rates have fewer opportunities to spread the virus.

What about vaccines for children?

High-risk children age 6 months and older who have conditions that increase the risk of severe COVID-19 are still eligible for the vaccine under the new framework. As of now, healthy children age 6 months and older without underlying medical conditions will not have routine access to COVID-19 vaccines until further clinical trial data is available.

Existing vaccines already on the market will remain available, but it is unclear how long they will stay authorized and how the change will affect childhood vaccination overall.

Libby Richards, Professor of Nursing, Purdue University

This article is republished from The Conversation under a Creative Commons license. Read the original article.