Association Between Excess Sleep Duration and Risk of Stroke: A Population-Based Study

Excess sleep is associated with higher risk of stroke, but whether the risk is modified by age and if it remains elevated after accounting for the competing risk of death is not well understood.

We used nine years of the Canadian Community Health Survey between 2000 to 2016 to obtain self-reported sleep duration and created a cohort of individuals without prior stroke, heart disease, or cancer. We linked to hospital records to determine subsequent admissions or emergency department visits for acute stroke until December 31, 2017. We used Cox proportional hazard models to determine the association between sleep duration and risk of stroke, assessing for modification by age and sex and adjusting for demographic, vascular, and social factors. We obtained cumulative incidence of stroke accounting for the competing risk of death.

There were 82,795 individuals in our cohort who met inclusion criteria and had self-reported sleep duration, with 1705 stroke events in follow-up. There was an association between excess sleep (≥10 h/night) and risk of stroke in those <70 years (fully adjusted hazard ratio 2.29, 95% CI 1.04-5.06), but not ≥70 years of age, with a similar association after accounting for the competing risk of death.

Sleep duration ≥10 h/night is associated with increased risk of stroke in those <70 years of age. The findings support current guidelines for 7-9 h of sleep per night. Further research is needed to elucidate the relationship between sleep and cerebrovascular disease.