Sleep is a new and surprising risk factor for heart disease, according to a recent study.
Traditionally, there has always been an ongoing debate as to what is considered an ideal amount of sleep. Typically, one decides on the amount of sleep required based on “how tired they feel”. There have been numerous recommendations from various medical societies suggesting anywhere from six to ten hours of sleep a night. Until recently there was no objective analysis of health benefits of sleeping. It is well accepted that being sleep deprived caused lack of concentration, made you less communicative (or cranky), increased the risk of the common cold and other infections. Its effect on the heart had never been studied. However, based on a recent study done by Dr David P. White and Dr. Sanjay Patel from Harvard University, there are some definite benefits.
The traditional risk factors for heart disease include obesity, smoking, family history, high cholesterol, diabetes, inactivity and high blood pressure. Sleep is a new and surprising risk factor for heart disease according to Drs. White and Patel. They studied 70,000 women for ten years and collected data on their sleep habits and the eventual risk of heart disease.
Their findings revealed that women who slept less than six to seven hours per night had a steep increase on their risk of heart attack. Women who slept five hours, had a forty percent increase in the risk of having a heart attack as compared to women who slept eight hours. Similarly, sleeping longer than eight hours seemed to increase the risk of heart attack, although not quite as dramatically.
The correlation can be due to several mechanisms. Some could be related to the causes of not sleeping eight hours.
Inability to sleep well may be an early sign of heart disease. This may need to be evaluated by a physician.
Also, when we are sleeping well, blood pressure tends to be lower. Consequently, if we don’t sleep eight hours, blood pressure throughout the length of the day may tend to be higher. Higher blood pressure makes the heart work harder.
Another important factor relates to the increase in adrenalin-like hormones. In a sleep-deprived state, there is an increase in the activation of the sympathetic system (adrenalin generating system). This raises blood pressure as well as causes narrowing of the arteries, which raises the likelihood of having a heart attack. Similarly, cortisol, another “stress hormone” which recently has become a popular target for weight reduction solutions such as “Corti-Slim”, also increases. This raises blood sugar, blood pressure and the risk of a heart attack.
It is clear that less sleep may be putting you at risk for a heart attack. The obvious solution is to sleep longer. However, sleeping longer than eight hours has also been shown to increase risk of heart attack. The women who tended to sleep longer than eight hours were less active, weighed more, and smoked and drank more. These could be potential explanations for the increased risk.
It appears that researchers can't be sure if poor sleep is the cause of heart problems or just an early sign of the disease. Yet the length of sleep may just be part of the equation. Experts have identified another potential problem: sleep apnea. Sleep apnea is a condition that is characterized by a collapse of the airway in certain people during sleep. In other words, the airway behind the tongue, the uvula (that thing that hangs in the back of your throat), and the soft palette collapses in these individuals when they go to sleep. This in turn leads to obstruction of the airway to the point where they can't breathe. When that occurs, they transiently arouse, take three or four breaths, open up the airway and go back to sleep. This cycle repeats throughout the night. The most common sign of sleep apnea is snoring with periods of no breathing. Often people wake in the morning feeling inadequately rested and may fall asleep easily during the day.
There is evidence that sleep apnea causes drops in oxygen saturation and increase in carbon dioxide levels while sleeping. It clearly contributes to the development of high blood pressure, and leads to the development of heart attacks, strokes, and congestive heart failure as well. If there is any concern that you may be suffering from sleep apnea, you should bring this to the attention of your doctor.
Although, this discussion highlights the importance of good sleep for maintaining good heart health, it is one of the many aspects of living required for optimal heart health. A good diet and exercise is vitally important. Stress reduction is a very important aspect of risk reduction. Regular exercise and relaxation therapy such as meditation etc. also have a very beneficial effect, and can also alter the amount of sleep needed. It is also reasonable to assume that quality of sleep plays a very important part in the overall health of your heart. A good night’s sleep is what your doctor should order.
The contents are meant for informative, educational purposes only. Formal recommendations can only be made by physicians involved in your care. Please check with your physician before acting on any part of this article.