Get Active! Physical Inactivity and Low Fitness Are Serious Threats to Cardiovascular Health

In the past 5 years, Dr Steven Blair (University of South Carolina, Columbia) has covered nearly 12 000 miles by taking five million steps each year, or an average of 13 600 steps per day. He warns that low fitness is at least as important as other cardiovascular risk factors, such as high cholesterol levels or elevated blood pressure.

In the US, however, only a minority of physicians ask their patients about physical activity, let alone get an objective measure of how much exercise their patients are getting, he said.

"Every primary-care medical practice in the world should have a box full of pedometers," said Blair. "In the US, you can get those for $10 or less." Somewhat tongue-in-cheek, Blair said that if he were the "grand poobah" of medical care, he'd sue physicians for medical malpractice if they failed to prescribe physical activity—anywhere from 8000 to 10 000 steps per day—for their patients.

Blair made the comments last week at EAS 2015: the European Atherosclerosis Society 2015 Congress, in a session devoted to physical inactivity, changing lifestyle patterns, and cardiovascular-disease prevention. "If I can do it, your 45-year-old patient can do it," said Blair. "Give them a pedometer or an accelerometer, and get them out there being physically active."

During the lecture, Blair, a long-time advocate on the wide-ranging benefits of physical activity in disease prevention, who previously stated that physical inactivity is one of the biggest public-health problems of the 21st century, lamented that the US Institute of Medicine and the National Academy of Sciences recently failed to recognize the strength of evidence showing physical inactivity's impact on mortality.

He noted that as far back as 1989, the Aerobics Center Longitudinal Study (ACLS) showed that simply shifting from a low level of fitness to moderate fitness could significantly reduce all-cause mortality. In later years, studies showed a significant reduction in cardiovascular mortality in men and women who improved their fitness. And finally, Blair pointed to their 2005 analysis of the ACLS cohort of 2316 men with physician-diagnosed diabetes but without a history of stroke or MI. In that study, low cardiorespiratory fitness was associated with an increased risk of cardiovascular mortality among patients who were normal weight, overweight, and obese.

"In the US, it is impossible to go for a medical exam and not have your height and weight measured and your BMI calculated," said Blair. "You can't escape it. But I'm going to ask you, 'Is it possible to escape the doctor's office without getting a fitness test?' Yes! In the US, only about 20% to 25% of physicians even ask about physical activity. This needs to change."

Blair said cardiorespiratory fitness and changes in fitness are even more important than weight loss. In one analysis that tracked cardiovascular risk factors, fitness levels, and body weight over time, cardiovascular disease mortality was significantly reduced among individuals who gained fitness but was unchanged among individuals who lost weight. Blair said he would encourage patients to control their weight—there are no fit people with a BMI of 55, he noted—but stresses that fitness is a much better prognostic tool.

"Changing your fitness does make a difference," said Blair.

Earlier this year, the World Health Organization outlined a global action plan for reducing the number of premature deaths from noncommunicable diseases by 25% by 2025. To get there, it identified nine targets that address various risk factors, including the goal of reducing smoking, reducing saturated fat intake, reducing physical inactivity, and halting the rise in diabetes and obesity, among others. Regarding physical activity, WHO suggests efforts to reduce physical-inactivity levels by 10% worldwide. The measures outlined by WHO are considered "best buys" and can be accomplished with as little investment as $1 to $3 per person worldwide.

Urbanization and Lifestyle

In another EAS presentation, Dr Mai-Lis Hellénius (Karolinska Institute, Stockholm, Sweden) said there are challenges even among European countries that appear to have gotten the message about physical activity. Swedes, for example, exercise the most of all European countries, with 70% of individuals exercising at least once per week, but physical inactivity remains a problem.

"Swedes, together with people from Denmark, the Netherlands, Luxembourg, and the Czech Republic, also spend the most amount of time sitting," said Hellénius. "In Sweden, we had the highest proportion of people sitting more than 8.5 hours per day."

The Lancet series on physical activity in 2012, which was reported by heartwire , suggested that physical inactivity is responsible for nearly 10% of premature deaths worldwide, or more than 5.3 million deaths in 2008. Based on these estimates, physical inactivity is responsible for more premature deaths than smoking. These findings led to the now popular expression, "Sitting is the new smoking."

Regarding other metrics of a healthy lifestyle, Hellénius noted that lifestyle behaviors alone could prevent the vast majority of MIs in men and women. In one Swedish study, four out of five MIs could be prevented in men who adhered to five low-risk lifestyle behaviors: a healthy diet, moderate alcohol intake, no smoking, being physically active, and having no abdominal adiposity. That same study found that just 1% of men adhered to all five healthy lifestyle behaviors. For women, just 5% meet all five parameters, said Hellénius.

Dr Naveed Sattar (University of Glasgow, Scotland), who also spoke during the session, pointed to the cardiovascular problems that arise with migration from a rural to urban environment, or from developing/low-income countries to industrialized/higher-income countries. As has been documented previously, these shifting immigration patterns have significantly altered the cardiovascular risk profile among many populations.

"There will be more obesity and more diabetes, and these are epidemics that are upon us now," he said.

In some Middle Eastern countries, for example, particularly those that have undergone a rapid urbanization, one in four individuals have type 2 diabetes. He noted there was a paradox in that death from cardiovascular disease is lower in urban areas because access to medical care is better, even though cardiovascular risk factors are higher. The result is that life expectancy will rise in the coming years in urban/lower-income countries, but individuals will have more comorbidities.

"I think people are going to live longer with their diabetes," said Sattar. "They're not going to die from their heart attacks. We're seeing this in the UK now, in Europe, and in North America. The same pattern will occur around the world, I predict."