BOSTON—Regularly sleeping for less than six hours significantly increases the rate of stroke symptoms among middle-aged and older persons with a normal BMI and a low risk of sleep-disordered breathing, according to a study presented at the 26th Annual Meeting of the Associated Professional Sleep Societies.
Researchers found no association between six-hour sleep duration and stroke symptoms among overweight and obese persons.
Unadjusted results indicated that sleep duration of less than six hours and sleep duration of nine hours or more were strong predictors of stroke symptoms, but the predictive strength of these factors decreased when the data were adjusted, said Megan Ruiter, PhD, a postdoctoral fellow in preventive medicine at the University of Alabama at Birmingham. She and her colleagues noted a significant interaction between sleep duration and BMI, however.
Sleep duration of less than six hours was strongly associated with a greater incidence of stroke symptoms in the fully adjusted data model for participants with normal BMI. Short sleep is associated with endothelial dysfunction, and it could increase stroke risk by this mechanism, said Dr. Ruiter.
Dr. Ruiter and her colleagues analyzed data from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study to determine whether sleep duration predicted self-reported stroke symptoms among individuals at low risk for sleep-disordered breathing. The study encompassed 30,239 Americans age 45 and older. The investigators collected participants’ self-reports of their average sleep duration. At six-month intervals, the researchers obtained subjects’ self-reported stroke symptoms.
A total of 5,666 participants had no history of stroke, transient ischemic attack, or stroke symptoms and were not at high risk for sleep-disordered breathing. Dr. Ruiter’s team estimated the hazard ratios regarding predicting time from measurement of sleep duration to first stroke symptom. Models were adjusted for demographic information, Framingham stroke risk factors, depressive symptoms, anxiety, and various health behaviors.
The analysis of the results suggests that improving sleep might lower stroke risk in persons with normal BMI, said Dr. Ruiter. “We need increased physician awareness of sleep problems,” she added.
Sleep fragmentation could play a part in the increased rate of stroke symptoms among individuals of normal BMI, but more data are required to answer the question clearly. Dr. Ruiter and her colleagues will continue to study the relationship between sleep and stroke symptoms.