Sleep and Heart Health: What Sleep Technologists Should Know
Sleep and heart health are more closely related than previously thought
Of all the reasons to get a good night's sleep, protecting your heart might not be top of mind. But maybe it should be. Sleep duration has decreased 1.5 to 2 hours per night per person in the last 50 years.
Several recent studies show that getting less sleep can put you at higher risk of cardiovascular diseases and heart problems. In fact, many medical disorders may disturb your sleep and disturbed sleep may affect your health, leading to a vicious cycle if you ignore your sleep problems.
What should sleep technologists know about this risk?
Study 1: Short sleepers have up to a 48% increased risk of coronary heart disease
In a study that looked at 15 medical studies that involved 475,000 people, The European Heart Journal review found that short sleepers had a 48% increased risk of developing or dying from coronary heart disease (CHD) in a seven to 25-year follow-up period (depending on the study) and a 15% greater risk of developing or dying from stroke during this same time. Interestingly, long sleepers -- those who averaged nine or more hours a night -- also showed a 38% increased risk of developing or dying from CHD and a 65% increased risk of stroke.
But the authors of the study reminded readers that the mechanisms behind shortened and prolonged sleep and heart disease aren't completely understood. It's not that lack of sleep alone causes heart disease, it's that it increases the risk factors for developing heart dieseases.
Study 2: Frequently having a poor quality of sleep can harden your arteries
One 2008 study from the University of Chicago found a link between shortened sleep and increased coronary artery calcification (calcium deposits), which is considered to be a good predictor of subsequent coronary artery disease.
This study also revealed that shorter sleep predicted worsening hypertension (high blood pressure). Because most people's blood pressure falls at night, it may be that short sleepers do not experience the benefits of blood pressure decreasing during sleep.
But can you reverse this trend? Researchers aren't sure. Part of the reason is that sleep's effects on the heart are a relatively new area of study. Another is that measuring sleep is complicated. Many studies rely on self-reporting, which may not always be accurate. Having your sleep measured objectively involves wearing an activity monitor, which may change the way you usually sleep.
It's pretty safe advice for the majority of people that sleeping less than six hours a night is probably not good, according to these two studies.
Are you not gettinbg a good night's sleep either? Read our article on how you can improve your sleep and start feeling better in 5 simple ways.
A recap of what sleep technologists should know about sleep's relationship to heart health
So how can getting enough sleep protect your heart?
- Make sure you get enough good-quality sleep. Doing so will decrease the work of your heart, as well as decrease your blood pressure and heart rate.
- People who are sleep-deprived show less variability in their heart rate, meaning that instead of fluctuating normally, the heart rate usually stays elevated, which makes your heart look like it is in a heightened stress mode.
- Lack of sleep can increase insulin resistance, a risk factor for the development of type 2 diabetes and heart disease.
- Shortened sleep can increase the release of CRP, or C-reactive protein, which is associated with stress and inflammation.
- If your CRP is high, it's a risk factor for cardiovascular and heart disease.
- Shortened sleep can also interfere with your appetite regulation. So you may end up eating more or eating foods that are less healthy for your heart.