By Marc Braman, MD, MPH
MB (Marc Braman, MD, MPH):
Our topic this session is “Atherosclerosis & Sleep.” I’m Dr. Braman and I’m joined by our sleep expert, Dr. Gurley. Welcome back, Dr. Gurley.
VG (Virginia Gurley, MD, MPH):
Thank you, Dr. Braman.
MB:
Heart disease has been our #1 killer for many years. In an earlier session we talked about how not getting enough quality sleep increases our chances of developing heart disease and high blood pressure. What about atherosclerosis, specifically, which is, of course, the condition where large blood vessels get think and stiff and then build up plaque. That is what we mean most of the time when we refer to heart disease – does sleep have an effect on our risk for atherosclerosis?
VG:
Yes, there are quite a few studies showing that too little sleep and poor quality sleep can both increase the risk for developing atherosclerosis. Most of these studies looked at one of the key signs of atherosclerosis, which is thickening of the walls of the carotid arteries. The carotid arteries are the main blood vessels carrying oxygen and energy to our brain, and in people who don’t get enough sleep, the carotid walls are thicker and stiffer, which means worse atherosclerosis and a greater risk for heart attacks and strokes.
MB:
I see. Many times, not enough sleep and poor quality sleep are due to lifestyle habits that interfere with sleep, (like too much light at night, eating late, and not getting enough light during the day), but what about the effect of conditions that disrupt sleep, like obstructive sleep apnea or night time asthma?
VG:
Good question! Quite a number of studies have found an increased risk for atherosclerosis in people with obstructive sleep apnea, or OSA. It seems several factors may cause this increased risk – one is the increase in inflammation that occurs when sleep is disrupted by breathing difficulties, and this increased inflammation then increases carotid artery thickening. This is may be why uncontrolled asthma also goes along with increased risk for atherosclerosis.
MB:
Interesting. What are the other factors linking OSA with atherosclerosis?
VG:
Most people with OSA are very load snorers, in fact loud snoring is one of the key symptoms of OSA. But here’s the thing, not all snores are made alike. When a recent study looked at the sound waves in snores of people with OSA, they found that people who’s snores have more of some specific sound waves, also have more thickening of their carotid artery walls. It seems the energy in some sound waves from snoring contributes to atherosclerosis.
MB:
So perhaps this is a little bit like singers. Some singers you want to listen to and some you don’t and can be painful. Do we know why sleep problems create inflammation that contributes to atherosclerosis?
VG:
To some extent, yes. Looking more broadly at sleep and the inflammatory processes underlying atherosclerosis, there are a growing number of studies linking body clocks with inflammation-related diseases like atherosclerosis. So, adopting lifestyle habits that support quality sleep helps keep one’s body clocks healthy and thereby reduces your chances for atherosclerosis, stroke and heart attacks.
MB:
Which, of course, would be a very big deal. So, good, healthy, refreshing sleep is an important part of preventing and treating atherosclerotic or common heart disease. Thank you so much, Dr. Gurley!
VG:
Thank you so much, Dr. Braman.
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