Long naps tied to increased stroke risk
Taking long naps during the day, sleeping longer at night, and having poor sleep quality were associated with increased risk for stroke, according to a study published in Neurology, the medical journal of the American Academy of Neurology.
“These results highlight the importance of moderate napping and sleeping duration and maintaining good sleep quality, especially in middle-age and [among] older adults,” Xiaomin Zhang, MD, PhD, of Huazhong University of Science and Technology in Wuhan, China, said in a press release.
Zhang and colleagues conducted a prospective cohort study evaluating stroke incidence in 31,750 adults with an average age of 61.7 years. Participants, who were retired employees from a company in China, completed baseline medical examinations and questionnaires at enrollment and during follow-up.
Researchers found that sleeping 9 hours or longer per night was associated with a greater risk for stroke (HR = 1.23; 95% CI; 1.07-1.41) compared to sleeping 7 to 8 hours per night.
Compared with napping for 1 to 30 minutes during the day, napping more than 90 minutes was associated with a greater risk for stroke (HR = 1.25; 95% CI; 1.03-1.53).
Researchers said poor sleep quality was associated with a 29% increase in risk for any stroke compared with good sleep quality. The risk for ischemic stroke was 28% higher and the risk for hemorrhagic stroke was 56% higher in those who reported poor sleep quality.
Zhang and colleagues found that the risk for stroke was higher among those who reported both sleeping 9 hours or longer each night and took naps 90 minutes or longer during the day (HR = 1.85; 95% CI 1.28-2.66) compared with those who slept 7 to 8 hours per night and napped 1 to 30 minutes during the day.
Additionally, they found that those who reported sleeping 9 hours or longer each night and having poor sleep quality had a higher risk for stroke (HR = 1.82; 95% CI 1.33-2.48) compared with those who reported sleeping 7 to 8 hours per night and having good sleep quality.
The researchers noted that their study shows an association, not causation, between long nap and sleep duration and stroke.
“More research is needed to understand how taking long naps and sleeping longer hours at night may be tied to an increased risk of stroke, but previous studies have shown that long nappers and sleepers have unfavorable changes in their cholesterol levels and increased waist circumferences, both of which are risk factors for stroke,” Zhang said in the release. "In addition, long napping and sleeping may suggest an overall inactive lifestyle, which is also related to increased risk of stroke.” – by Erin Michael
Disclosure: The authors report no relevant financial disclosures.