Sleep impairments linked to increased risk for acute stroke

Key takeaways:

• Sleep disturbance symptoms were common and associated with increased odds of acute stroke.
• Cumulative sleep symptoms were associated with graded increased risk for stroke.

Symptoms of sleep disturbance, including long or short duration, impaired quality and difficulty getting to or maintaining sleep, were significantly associated with increased odds of stroke, according to research presented in Neurology.

“Impairments in sleep represent a spectrum of disturbance, from mild deviations in duration to impairments in different domains, associated symptoms through to complex syndromes,” Christine E. McCarthy, MSc, of the department of medicine at the National University of Ireland, and colleagues wrote. “Prior epidemiologic studies have evaluated the association of these sleep parameters and stroke, but the methodology and results are inconsistent.”

To evaluate associations between sleep disturbance symptoms and risk for acute stroke, researchers conducted the international INTERSTROKE case-control study, which included 4,496 individuals who presented with first acute stroke (ischemic stroke, n = 1,799; intracerebral hemorrhage, n = 439) and controls matched by sex and by age.

McCarthy and colleagues assessed sleep symptoms in the previous month via a comprehensive questionnaire that addressed hours of nocturnal sleep duration, sleep quality, sleep onset latency, nocturnal awakening and breathing-related sleep problems. They adjusted for age, occupation, marital status and modified-Rankin Scale at baseline in a primary analysis and made subsequent adjustments for behavioral risk factors, including alcohol consumption, smoking, diet quality and BMI, and other disease risk factors.

According to results, less than 5 hours of sleep (OR = 3.15; 95% CI, 2.09-4.76), more than 9 hours of sleep (OR = 2.67; 95% CI, 1.89-3.78), impaired sleep quality (OR = 1.52; 95% CI, 1.32-1.75), difficulty getting to sleep (OR = 1.32; 95% CI, 1.13-1.55) or maintaining sleep (OR = 1.33; 95% CI, 1.15-1.53), unplanned napping (OR = 1.59; 95% CI, 1.31-1.92), napping longer than 1 hour (OR = 1.88; 95% CI, 1.49-2.38), snoring (OR = 1.91; 95% CI, 1.62-2.24), snorting (OR = 2.64; 95% CI, 2.17-3.2) and breathing cessation (OR = 2.87; 95% CI, 2.28-2.6) were all significantly linked to risk for acute stroke.

Researchers additionally reported that these associations were additive, with a graded increase in odds of acute stroke with cumulative impairments.

“Our results suggest that individual and cumulative symptoms of sleep disturbance may be important modifiable risk factors for stroke, and/or their presence identifies individuals at increased risk of stroke,” McCarthy and colleagues wrote. “Our findings also suggest a complex relationship of sleep impairment, intermediate cerebrovascular risk factors and stroke risk.”