Poor Night's Sleep Increases Odds of Stroke, Heart Attack
Failure to get a good night's sleep can boost the odds of having a stroke or heart attack. Researchers say poor quality sleep increases inflammatory hormones that lead to poor blood vessel health. Past studies have looked at acute sleep deprivation that occurs for more than 24 hours. The new study shows an increased risk of heart attack and stroke that can happen from six or less hours of good sleep.
Less than Six Hours of Sleep Boosts Inflammatory Markers
For the study, researchers measured inflammatory markers in the bloodstream, matching their findings with the Pittsburgh Sleep Quality Index survey and hours of sleep.
Fibrinogen, IL-6 and C-reactive protein, inflammatory markers that can mean poor blood vessel health were found to be higher in people who reported less than six hours of sleep, compared to those getting six to nine hours. C-reactive protein levels that are widely used to gauge a person’s risk for heart attack and stroke were about 25 percent higher in people sleeping less.
Alanna Morris, MD, a cardiology fellow at Emory University School of Medicine says, "Most of the studies looking at the body's response to lack of sleep have looked at subjects who have been acutely sleep deprived for more than 24 hours in experimental sleep laboratories. Nothing of this sort has been investigated in epidemiologic studies.”
Dr. Morris says, "For people who got little sleep, the C-reactive protein levels were increased, but still in the range of what health authorities would consider low to intermediate risk. However, our study population represents a community-based population [as opposed to patients in the hospital or with known cardiovascular disease], so they have overall lower risk and lower C-reactive protein levels than many of the high risk populations in other studies."
Previous research finds sleeping seven or more hours a night leads to a longer life. The new study lends insight into why sleeping less is tightly linked to high blood pressure, obesity, diabetes and psychological stress, but "It remains uncertain whether short sleep duration contributes directly to cardiovascular mortality, or whether it is a mediating or moderating factor," explains Morris.
Even after correcting for other risk factors like stroke, obesity and diabetes, poor quality sleep was still found to raise inflammation associated with poor blood vessel health. The findings that poor sleep could increase the chances of stroke and heart attack come from a survey of 525 middle-aged people participating in the Morehouse-Emory Partnership to Eliminate Cardiovascular Health Disparities (META-Health). The findings are presented by Dr. Morris today at the American Heart Association Scientific Sessions in Chicago.
Copyright © 11/14/2010
Kathleen Blanchard RN