A new study has shown a J-shaped relationship between sleep duration and future stroke risk, with a particularly strong signal associated with long sleep duration.
Investigators at the University of Cambridge in the United Kingdom found that short sleep was associated with an 18% increased stroke risk (not statistically significant), and long sleep was associated with a 46% increase in stroke risk after adjustment for conventional cardiovascular disease risk factors and comorbidities.
In addition, those who reported persistently long sleep had double the stroke risk compared with those with persistently average sleep duration, and people whose sleep duration increased markedly over the course of a 4-year period had almost a fourfold increased risk.
The researchers also performed an updated meta-analysis of studies looking at sleep duration and stroke that showed very similar results.
“We believe long sleep duration is an indicator of increased stroke risk. We are not suggesting that sleep causes the increased risk, but it could be a useful marker of other underlying conditions that do increase stroke risk,” lead author Yue Leng, MPhil, told Medscape Medical News.
“By asking one question about how many hours a patient sleeps and whether this has changed in recent years, doctors could ascertain information about that patient’s risk of stroke,” he added.
The study was published online February 25 in Neurology.