Your sleep affects everything… and everything affects your sleep. More and more, we understand the impact of sleep dysfunction on our health and, in particular, on heart disease risk and outcomes.
Insufficient sleep is defined as getting six hours or less of shuteye a night. According to the National Sleep Foundation, most adults need seven to nine hours of sleep each night.
There is a very small population of “short sleepers,” who routinely sleep five hours or less over a 24-hour period and function normally despite this reduced sleep. However, this is extremely uncommon, and most of us would suffer adverse medical and psychological consequences if we attempted to do this, especially on a regular basis.
Insufficient sleep has been shown to increase the risk of cardiovascular mortality, high blood pressure and diabetes.
A recent study in the Journal of the American College of Cardiology demonstrated that less than six hours of sleep a night over time increased the risk of coronary atherosclerosis. Lack of sleep can raise cortisol levels, which causes inflammation around your heart and raises blood pressure. Inflammation also can cause plaques in your arteries to break loose, lodging in vessels in the heart or brain and leading to a heart attack.
Sleep imbalance also can upset or confuse the release of hunger regulating hormones. Research shows that when we don’t get enough sleep, our leptin (internal appetite-suppressing hormone) levels fall and ghrelin (internal hunger-promoting hormone) levels increase. Thus, when you are feeling sleepy, you might also feel like you need to head for the fridge, instead of bed. Even when we exercise, our metabolism slows down if we don’t get enough sleep. This can potentially lead to obesity and diabetes, two of the primary causes of heart disease.
Obstructive sleep apnea
Obstructive sleep apnea is a common sleep disorder occurring when the muscles at the back of the throat relax to the point of obstructing the upper airway. Breathing can stop for up to 40 or more seconds. You do not receive enough oxygen, causing “mini-awakenings” (gasping for breath) up to several hundred times a night.
Obstructive sleep apnea is like someone smothering you repeatedly while you are asleep. This stress, or “fight or flight” response, is largely responsible for the cardiovascular risk associated with this condition.
Obstructive sleep apnea has been found to increase the risk of high blood pressure, strokes, heart attacks, sudden cardiac death, heart arrhythmias, as well as diabetes and obesity.
Insufficient sleep or obstructive sleep apnea puts our bodies into a stress state, trigger a cascade of events leading to these outcomes.