- Researchers say a lack of quality sleep can raise the risk of heart disease and stroke.
- They note that people with the highest sleep scores have a 75% percent lower risk of heart health issues than people with the lowest scores.
- Experts say many people don’t take their sleep habits as seriously as they should.
- Some tips for obtaining quality sleep include going to bed at the same time every night and making sure your sleeping area is dark and quiet.
Not getting enough sleep may lead to a higher risk of heart disease and stroke.
“The low prevalence of good sleepers was expected given our busy, 24/7 lives,” said Dr. Aboubakari Nambiema, PhD, MPH, a study author and postdoctoral researcher at INSERM (the French National Institute of Health and Medical Research). “The importance of sleep quality and quantity for heart health should be taught early in life when healthy behaviors become established. Minimizing night-time noise and stress at work can both help improve sleep.”
There have been many studies connecting poor sleep to heart disease, but most focus on a single sleep habit, such as sleep apnea or sleep duration.
The new study, which hasn’t been peer-reviewed or published yet, combined five sleep habits and looked at baseline sleep scores and changes over time as well as incidences of cardiovascular disease.
It included 7,200 participants who were studied between 2008 and 2011.
Participants were initially free of cardiovascular disease and were an average age of 59 years with 62 percent being male.
Researchers checked for coronary heart disease and stroke every two years for a decade. They reported that 10 percent of participants had an optimal sleep score (one of five, with five being optimal) and 8 percent had a poor score at baseline.
During the following eight years, the number of participants who developed coronary heart disease or stroke decreased by 22% for every one-point rise in baseline sleep measurements. Compared to people with a score of zero or one, participants with a score of five had a 75% lower risk of heart disease or stroke.
Researchers estimated if all participants had an optimal sleep score, 72 percent of new cases of coronary heart disease and stroke could have been avoided annually. They found over time, a one-point increase in sleep score was associated with a 7% reduction in the risk of coronary heart disease or stroke.
Colin Espie, PhD, the co-founder of sleep health company Big Health and a professor of sleep medicine in the Nuffield Department of Clinical Neurosciences at the University of Oxford in England, told Healthline that sleep’s importance can be too obvious.
“Like we need oxygen, we don’t think enough about it until we have a problem,” Espie told Healthline. “I’ve noticed, though, that we are becoming more attentive in healthcare to sleep as a pillar of health. The research evidence has been mounting, but we still have a way to go to understand that how we sleep is just as important as what we eat as a determinant of health.”
Espie noted that sleep needs change as we age.
“One example of age-related change is that as we get older there’s an aging of the circadian clock which results in a shift of our natural sleep rhythms,” he said. “Our sleep is more fragmented in later life and less deep sleep is normal, as are intermittent wake periods.”
“We need to avoid dips in oxygen supply to the body and the brain, at all times, but this includes at night,” Espie added. “When we are asleep, some people are prone to breathing pauses or apneas and this not only fragments sleep but when severe they can also lead to cardiovascular risk. In addition, good sleep is critical for recovery for those who may have experienced a stroke.”
Dr. Nick West, a cardiologist and chief medical officer of Abbott’s vascular business, told Healthline that getting enough sleep can be a balancing act.
“The relationship between the amount of sleep and risk of cardiovascular disease is complex. Both lack of sleep (less than six hours per night) and excess sleep (more than nine hours) have both been associated with increased risk in observational studies,” West said.
“In cases of sleep deprivation, endocrine/hormonal and hemodynamic changes can be observed as well as systemic inflammation,” he added. “These can result in the development of obesity/adverse body mass index, type 2 diabetes mellitus, and high blood pressure, all of which increase the risk of stroke, heart attack and cardiovascular death.”
Shift work, disruption, and sleep deprivation can contribute.
“The benefits of increasing sleep levels can be difficult to study given self-reporting of sleep amount, and the effect of sleep quality can be difficult to judge given its subjective nature,” West said. “That said, studies have shown that sleep extension to normal levels after sleep deprivation can help blood pressure and therefore reduce cardiovascular risk – and it is likely that the other physiological changes associated with sleep deprivation would likewise improve.”
Dr. Marc Helzer, a primary care physician specializing in family medicine with the University of Michigan Health-West, told Healthline that good sleep is more than just time spent in bed.
“Sleep is a complex process that progresses through three stages, with REM sleep being the goal for restoration of mind and body,” Helzer said. “Good sleep is continuous. Frequent awakenings for any reason disrupt and restart the stages of sleep, resulting in a ‘sleep debt’ that the brain is owed to reach full recovery.”
“Poor sleep hygiene — watching screens in bed — an uncomfortable mattress or environment and common medical problems can disrupt continuous sleep and result in signs of sleep deprivation – feeling slow, foggy, depressed, and having low energy,” he added.
Helzer said the risk of cardiovascular disease increases not just with age, but in some cases with weight gain that frequently comes with aging.
“As weight goes up and we age, the risk of apnea rises,” Helzer said. “Apnea is a partial stop of breathing. As breathing stops and becomes shallow, oxygen levels drop in the blood. To compensate, the heart rate increases dramatically, often irregularly with atrial fibrillation, which might only occur during sleep. This can create turbulence in the heart, causing blood clots that float on down the line causing strokes.”
The U.S. Centers for Disease Control and Prevention offersTrusted Source a variety of tips for getting a good night’s sleep.
Among them are going to bed at the same time every night, removing electronic devices from your sleep area, and making sure your bedroom is dark and quiet.