BILTHOVEN, the Netherlands — Getting at least seven hours of sleep a night further lowers the risk of CVD events--on top of the lowered risk from following four traditional healthy habits--according to a large, population-based study in the Netherlands published in the July 2, 2013 issue of the European Journal of Preventive Cardiology .
The Monitoring Project on Risk Factors for Chronic Diseases (MORGEN) study looked at how adequate sleep might enhance the benefits of being physically active, eating a healthy diet, not smoking, and drinking alcohol in moderation.
"When we think of cardiovascular protection, we usually think of the traditional lifestyle factors, and also cholesterol and body mass index [BMI], [but] so far sleep has not been an issue," senior author Dr WM Monique Verschuren (National Institute for Public Health and the Environment, Bilthoven, the Netherlands), told heartwire . However, this study suggests that sleep is something that "doctors could discuss with their patients, and [counsel them that] if they don't sleep enough, it could be worthwhile to be more disciplined and go to bed an hour earlier in addition to [having] a healthy diet, being active, and stopping smoking."
If these findings are reproduced in other studies, sleep may be a lifestyle factor included in future guidelines for preventing CVD, she speculated. "It could be something that people could quite easily change in their lifestyle," she said, and could have a large public health impact, she added.
To Sleep, Per Chance to Dream
Previously, researchers found that people had an increased risk of CVD if they did not get seven to eight hours sleep, especially if they woke up feeling tired, Verschuren said. However, the effect of adding insufficient sleep on top of traditional CV risk factors was unknown.
In the current study, researchers analyzed data from 6672 men and 7967 women who participated in MORGEN, a prospective study of people aged 20–65 years living in the Netherlands who replied to a lifestyle questionnaire in 1994 to 1997.
Researchers defined five healthy lifestyle habits, as follows:
Spending 3.5 or more hours a week cycling or doing other sports at a moderate to vigorous intensity.
A modified Mediterranean diet score of five or higher.
One drink of alcohol or more a month.
Sleeping seven hours or more a night.
The population was fairly healthy: 52% were sufficiently active, 37% consumed a healthy diet, 91% of men and 78% of women consumed alcohol, 65% were nonsmokers, and 80% of men and 86% of women obtained sufficient sleep. Men and women were equally health conscious: 6% adhered to one or fewer and 12% adhered to all five healthy lifestyle habits.
During the 10–14 year follow-up, there were 607 composite CVD events: 129 fatal CVD events, 367 nonfatal MIs, and 111 nonfatal strokes.
Each factor on its own reduced the risk of CVD. The reduced risk for composite CVD ranged from 12% lower for following a healthy diet to 43% lower for not smoking; the risk of fatal CVD ranged from 26% lower for being physically active to 43% lower for not smoking. Getting a good night's sleep reduced the risk of composite CVD by 22% (HR 0.78) and fatal CVD by 43% (HR 0.57) compared with having insufficient sleep.
Not surprisingly, compared to people with fewer than two traditional healthy lifestyle habits, those who adhered to four traditional habits had a 57% lower risk of composite CVD and 67% lower risk of fatal CVD. People who added sufficient sleep to these four habits had an even greater benefit: a 65% lower risk of a composite CVD event and an 83% lower risk of fatal CVD.
Other studies have shown that "insufficient sleep is a risk factor for overweight. During the night there are restorative processes, and too little sleep has an impact on blood pressure and BMI," which might explain these findings, Verschuren said.
According to the authors, "If all participants adhered to all five healthy lifestyle factors, 36% of composite CVD and 57% of fatal CVD could theoretically be prevented or postponed."
The MORGEN study was supported by the Ministry of Health, Welfare, and Sport for the Netherlands and National Institute for Public Health and the Environment. The authors declared no conflicts of interest.
Heartwire from Medscape © 2013 Medscape, LLC
Cite this: Adding Sufficient Sleep to Four Healthy Habits Further Lowers CVD Risk - Medscape - Jul 05, 2013.