Lack of deep sleep contributes to high blood pressure

Alack of deep sleep may be one of the reasons why people develop high blood pressure. A study of older men published Monday found that those who got the least amount of deep sleep were 80% more likely to develop high blood pressure, compared to those who got longer, less interrupted sleep.

Researchers studied almost 800 men over the age of 65 who didn't have hypertension when the study started. They were given at-home sleep tests that looked at their sleep patterns and measured their non-rapid eye movement sleep, also known as "slow wave sleep," or deep sleep. Researchers monitored the men's blood pressure changes for a little more than 3 years. Results were published in Hypertension, a journal of the American Heart Association.

Previous studies have shown that when people get less than 6 hours of sleep per night, it can increase the risk of high blood pressure. If people wake-up frequently, due to sleep apnea, medications, or other health issues and cannot fall back asleep quickly, this can also negatively affect blood pressure.

"Our study shows for the first time that poor quality sleep, reflected by reduced slow wave sleep, puts individuals at significantly increased risk of developing high blood pressure, and that this effect appears to be independent of the influence of breathing pauses during sleep," explains study author Dr. Susan Redline, Professor of Sleep Medicine at Brigham and Women's Hospital and Beth Israel Deaconess Medical Center at Harvard Medical School in Boston.

Experts often refer to slow wave sleep as the time when the body is restoring its energy reserves: Blood pressure goes down, breathing slows and the heart rate drops. People usually fall into deep sleep during the early part of the night.

Redline says this new research suggests that if your blood pressure doesn't drop sufficiently while you're sleeping, it may damage your blood vessels. Too little deep sleep may also cause parts of the brain that control the release of a number of hormones and other substances related to maintaining proper blood pressure to work less efficiently.

So how do you know if you're getting too little deep sleep? First of all, listen to your body and your family.

"If you don't sleep properly, are tired during the day, you snore or your wife or husband says you don't breathe [while asleep], get it checked out to see if you have a sleep problem," explains Dr. Donald LaVan, National Spokesman for the American Heart Association. One way to determine this is by entering a sleep study.

Redline says there are a number of things people can do to increase the likelihood of getting enough deep sleep. Ask your doctor if any of your medications can interfere with your sleep and if there are any alternative drugs you can take. Redline also says there's some evidence that being physically and mentally active may help.

High blood pressure has been called the silent killer and puts people at increase risk for heart disease and other illnesses.

When it comes to your blood pressure, "sleep quality is something to pay attention to," explains Redline, "just as one would pay attention to your diet and physical activity levels."