For Your Heart’s Sake, Get out of Your Chair

Coronary artery calcification risk increased in those who sat for long periods

(RxWiki News) Sitting may feel nice, especially after a long day. Too much of it, however, isn't doing your heart health any favors.

A new study found that excessive sitting increased coronary artery calcification, or hardening of the arteries in the heart.

Past research has found a relationship between excessive sitting — called “sitting disease” — and an increased risk of heart disease, type 2 diabetes, cancer and early death. Excessive sitting is actually a lifestyle factor, which suggests it can be modified. Changing daily habits might allow people to prevent heart disease.

Even when study subjects got regular exercise, sitting appeared to counteract its effect. The authors of this study called for further studies to determine whether decreasing sitting time might also decrease heart disease risk.

Jacquelyn Kulinski, MD, assistant professor of cardiovascular medicine at the Medical College of Wisconsin, led this study.

Dr. Kulinski said in a press release, "It's clear that exercise is important to reduce your cardiovascular risk and improve your fitness level. But this study suggests that reducing how much you sit every day may represent a more novel, companion strategy (in addition to exercise) to help reduce your cardiovascular risk. I think the study offers a promising message. Reducing the amount of time you sit by even an hour or two a day could have a significant and positive impact on your future cardiovascular health.”

Coronary artery calcification (CAC) occurs when calcium deposits build up in the arteries of the heart. The arteries become less flexible. It is also a sign of plaque, a buildup in the arteries that can eventually cause the artery to narrow and cause a heart attack or stroke.

A person with a high coronary calcium score is considered to have a higher risk of a heart attack or stroke, Dr. Kulinski and team noted.

Dr. Kulinski and colleagues looked at heart scans on more than 2,000 adults who lived in Dallas, TX. Subjects were 40 to 60 years of age.

These researchers did not rely on reports of physical activity. Instead, they had these patients wear a motion-tracking device called an accelerometer.

These patients, who had no signs of heart disease, sat an average of five hours a day. Sitting time ranged from two to 12 hours a day.

Dr. Kulinski and colleagues found that each hour of sitting time was tied to a 14 percent increase in CAC. Even when the patients exercised, the amount of sitting time offset the exercise.

People who sat for longer periods tended to be older. They also weighed more and were likely to have diabetes or high blood pressure. These researchers accounted for other risk factors like smoking.

"The lesson here is that it's really important to try to move as much as possible in your daily life; for example, take a walk during lunch, pace while talking on the phone, take the stairs instead of the elevator and use a pedometer to track your daily steps," Dr. Kulinski said. "And if you do have a very sedentary job, don't go home at night and sit in front of the TV for hours on end."

This study will be presented March 12 at the American College of Cardiology's 64th Annual Scientific Session in San Diego. Research presented at conferences may not have been peer-reviewed.

Information on study funding and conflicts of interest was not available at the time of publication.

Review Date: 
March 8, 2015