Inactivity Pandemic Poised to Undo CVD Prevention Advances

Daily physical activity and exercise play a vital role in reducing the risk of chronic ailments, but there is a “pandemic” of inactivity—one that is only worsening, say experts—undoing a lot of the gains made in the fight against cardiovascular disease.

Harlan Krumholz, MD (Yale University School of Medicine, New Haven, CT), a clinical outcomes researcher, called the current moment of physical inactivity a “central threat” to US and global health.  

“I think we're in a moment in history where we're about to see a large segment of the population with very low levels of activity,” he told TCTMD. “Advances in technology have led to behaviors like binge watching and screen scrolling. That, and just computer time, in general, is unprecedented in our history. It’s good as always to encourage people to be active and to exercise, but I think we have a bigger issue, which is not just trying to extend historically from where people have been asked to try to get healthier habits, but to defend against these expanding trends.”

Sedentary time, said Krumholz, is at an extraordinary level, a situation only exacerbated by the COVID-19 pandemic and shifting to remote work. Children engage in much less physical activity and have less screen-free playtime than prior generations, and even people who are committed to exercise are spending more time sitting than they ever have in the past. Sitting is not only a danger to cardiovascular health, but to living a long and functionally healthy life, undercutting many of the gains made in the last century, he said.

And yet the cardiovascular upside of physical activity and exercise is very well known, with more and more research uncovering different mechanisms of benefit. In a review published last week in the European Heart Journal, Pedro Valenzuela, PhD (University of Alcala, Spain), and colleagues wrote about the myriad ways physical activity improves cardiovascular health, both for primary and for secondary prevention.

These include improved glucose control, reduced inflammation, and improved cellular integrity. In addition, there are improvements in endothelial function and endothelial cell integrity, as well as antiatherogenic and structural adaptations at the vascular level. There is also preclinical evidence of myocardial regeneration, with data showing that exercise after MI can enhance angiogenesis, perfusion, and left ventricular function. The benefits also go beyond moderating traditional risk factors, “partly owing to the release of exercise-derived factors or exerkines,” say the reviewers. These are a broad array of signaling molecules that exert an effect on different organ systems, including the cardiovascular system. Additionally, exercise can also protect against malignant arrythmias and promote cardioprotective preconditioning.

Tamanna Singh, MD (Cleveland Clinic, OH), a past member of the American College of Cardiology’s Prevention of CVD Council and Sports and Exercise Cardiology Council, said physicians know exercise reduces morbidity and mortality, but that the focus of research in the last couple of decades has been on treatment. While that emphasis is starting to shift, partly because of the staggering costs of healthcare, not enough people are doing the basics, she said.

“At least from my clinical and personal perspective, a lot of individuals are just not exercising,” she told TCTMD.

In their review, Valenzuela and colleagues say there is some debate around whether some people can do too much exercise, particularly those who engage in strenuous aerobic sports like marathon running or long-distance cycling events. Despite some concerns, there is no evidence linking participation to a higher risk of cardiovascular mortality. “In fact, there are consistent findings for the opposite trend,” they write. Data have also suggested large amounts of exercise and physical activity might be associated with higher coronary artery calcium scores and atrial fibrillation, but the clinical implications of these findings are still being studied, according to the reviewers.

Regardless, doing too much is not a problem the vast majority of the population faces. 

Perils of Sedentary Time

Worldwide, cardiovascular disease is the number one killer, responsible for more than 20 million premature deaths and millions more years lost to disability. Study after study highlights the worsening cardiovascular risk profile of the US population, with one suggesting that just 7% of adults had ideal cardiometabolic health. Obesity is rampant, as are diabetes, high blood pressure, and high cholesterol levels. A few years back, one study made headlines when researchers reported that one in two US adults had some form of cardiovascular disease.

The American Heart Association and World Health Organization (WHO) recommend 150 to 300 minutes of moderate-intensity physical activity per week or 75 to 150 minutes of vigorous-intensity physical activity (or a combination of the two). Both groups recommend that adults, including those with cardiovascular disease, do some form of resistance training twice per week to strengthen their muscles. They also recommend that people be less sedentary, stating everybody should be getting up and moving throughout the day.

Unfortunately, only a minority of adults are getting it done. The Centers for Disease Control and Prevention recently reported that less than half of US adults were getting enough aerobic physical activity, with fewer still adding in weekly muscle-strengthening exercises. Globally, the WHO reports that only one in four adults meet the daily recommendations for aerobic activity. 

Given that the benefits of exercise and physical activity are so well known, what will it take to change the behavior of the general public? For Krumholz, the solution will require moving beyond the doctor’s office. Instead of cheerleading people into different behaviors, there needs to be a large-scale societal shift where daily movement is the norm, he said.

I think we're in a moment in history where we're about to see a large segment of the population with very low levels of activity. Harlan Krumholz

“I mean, what are the expectations of the workplace? That you're sitting at your desk staring at Zoom for 6 hours a day?” he said. “Or are people encouraged to walk while they talk?  In other words, how are we thinking about our workplace? How are we encouraging people to stay active? [This is] not just like, ‘Hey, let's get a half hour at the end of the day where you can work up a sweat.’ How do we work on built environments so we’re sure there are safe places for people to walk and where healthy activities are normative? We need to build it in.”

Prolonged daily sedentary time has been linked to higher risks of CVD and mortality, with some data suggesting this risk exists regardless of physical activity levels while other studies found that it might be offset with more exercise. In one study, sitting for more than 10 hours per day was associated with incident CVD, while another found that 6 to 8 hours of daily total sedentary time, and 3 to 4 hours of TV watching, appeared to be the threshold at which the risk of death increased. 

In their review, Valenzuela and colleagues make the distinction between physical activity, which is any bodily movement that requires us to expend energy, such as walking the dog or cutting the grass, and exercise, which is more structured. Exercise might include supervised cardiac rehabilitation or running 5 km, for example.

Krumholz said he tries to take as many walking meetings as possible and encourages others to do the same. Patients, he added, tend to be more responsive when physical activity is tied to something fun and community oriented as opposed to a lecture from their doctor.

“When the workplace or groups of people get together and say, ‘Hey, let's all try to get 10,000 steps or 8,000 steps or 5,000 steps, something,’ it becomes part of a community activity,” he said. “It's not tied to disease, or death, or risk. That's probably in the end going to be more beneficial than telling somebody you might die earlier and lose your function. That kind of negative messaging around things people just want to filter that out.”

Singh says that trying to change behavior takes time as trust is built between patient and physician. She tries to help her patients understand their goal isn’t necessarily to meet a benchmark, but rather to find the intention and motivation to be more physically active. That will in turn lead to conversations about goal setting, which may involve improving cardiovascular fitness or CVD risk reduction.

“To really help individuals have insight, and to find that motivation to establish a consistent exercise and nutrition regimen, there has to be a switch that we as providers help turn on,” she said. “It’s a relationship. We can only provide guidance and motivation. At some point that desire has to come from the patient and there’s no medication that’s going to provide that. It’s really about support and continued positive feedback.”

Singh, who sees a lot of younger patients with cardiovascular morbidities, said that increased screen time is compounding the problem. It’s also contributing to a significant amount of stress. Depression and anxiety in turn feed into a negative loop of unhealthy lifestyle choices, including physical inactivity.

The glitz and the glam is always on these new devices and new ways to treat something, but that will only go so far. Tamanna Singh

“We need to kind of hit these things head-on early, because I think it's easier sometimes to establish lifestyle change when you're younger,” she said. “When you're in your forties and fifties and you already have established cardiac problems, you could still work on secondary prevention, but oftentimes you really have to work hard at showing people that even small changes can [have] large cardiovascular benefits.”

At the societal level, Singh thinks financially incentivizing prevention might help some people engage more in physical activity or regular exercise. For example, if people are trying to be active, maybe their health insurance rates or deductibles could be lower. It might also be possible for insurance companies or employers to cover the cost of exercise equipment, or perhaps even gym memberships, and doing so might kickstart a healthy habit.

“We should [also] be highlighting the prevention studies,” she said. “We should be highlighting how to implement change before things start to go haywire.”

Big Breakthroughs to Treat the Already Sick

In recent years, there have been a number of new drugs approved to lower LDL cholesterol, including PCSK9 inhibitors, inclisiran (Leqvio; Novartis), and bempedoic acid (Nexletol; Esperion), as well as treatments for high triglycerides. Similarly, the introduction of SGLT2 inhibitors, drugs that were initially developed for type 2 diabetes, have been shown to be beneficial in patients with heart failure. Glucagon-like peptide 1 receptor agonists also were developed for the treatment of diabetes but are now increasingly being used in obesity.

Despite the availability of these newer drugs, cardiovascular health is only declining, say researchers.

“Look at what we're doing,” said Krumholz. “We're spending more and more money, we're touting our breakthroughs louder and louder, and life expectancy is declining and not just because of the pandemic, and not just because of opioids. Multimorbidity is up, hypertension is up, a lot of things that can be tended to with very basic interventions [are up]. If anything, we're taking steps backward. I'm all for the breakthroughs and they’re exciting, but when you look at the net, [it’s] trillions of dollars beyond inflation poured into the healthcare system every year.”

“The glitz and the glam is always on these new devices and new ways to treat something, but that will only go so far,” added Singh. “Technology can advance only at a certain rate and there's so many stipulations that makes someone a candidate for certain things, whereas every single person is a candidate for preventive change and preventive habits.” 

Increased educational efforts focused on primordial and primary prevention might help, as would changing the importance placed on certain types of information, said Singh.

“Prevention may not be sexy, but prevention is what we need right now, particularly when we’re thinking about waste and sustainability,” she said. “In my opinion, there’s a lot of waste that comes with doing a lot of procedures. With prevention, there’s none. It’s just gains.”