A team of researchers from Duke University Medical Center recently conducted a study of men and women with no history of sleep disorders to examine whether a person's sex has an effect on subjective sleep and sleep-related symptoms considered risk factors for cardiovascular and metabolic health.
Using the Pittsburgh Sleep Quality Index, the researchers evaluated 210 healthy, middle-aged men and women for sleep quality and frequency of sleep symptoms. Participants self-reported the quality and eventfulness of their sleep on a sleep quality questionnaire, and poor sleepers were defined as people having frequent trouble falling asleep (more than two days per week), taking more than 30 minutes to fall asleep or waking frequently during the night. Blood samples were used to measure biomarkers and to assess risk for coronary heart disease and diabetes.
About 40% of the men and women in the study population were classified as poor sleepers. Women self-reported a higher degree of sleep disruption than men, and they also had higher levels of biomarkers. In particular, study participants who reported more frequent difficulty falling asleep and taking more than 30 minutes to fall asleep were associated with greater psychological stress, higher fasting insulin levels, the presence of fibrinogen and more inflammatory biomarkers than those participants who reported better quality sleep. Women with poorer quality sleep also had higher levels of CRP and interleukin-6.
