Inflammation is a risk factor for heart disease and stroke. A study from researchers at Emory University School of Medicine revealed a possible link between poor quality of sleep or not enough sleep and inflammation. The researchers evaluated sleep quality in a survey of 525 middle-aged men and women. They found that participants who reported sleeping six hours or less had higher levels of three inflammatory markers: fibrinogen, IL-6 and C-reactive protein (CRP). Notably, CRP levels were 25 percent higher in individuals who reported sleeping fewer than six hours a night compared to those who reported sleeping six to nine hours. The difference remained significant even after controlling for other risk factors including smoking, blood pressure, diabetes and obesity. Even with the increase in inflammatory activity, the researchers noted that CRP levels among this group were still in the range of what is considered low to medium risk. Earlier research has shown that sleeping between seven and eight hours a night is associated with longer lives. The researchers aren't sure exactly how short hours of sleep may contribute to heart disease deaths. The data were presented at the American Heart Association Scientific Sessions in Chicago this month.