Sleep Duration and Stroke: Prospective Cohort Study and Mendelian Randomization Analysis.

Area of Science:

• Neurology
• Epidemiology
• Genetics

Background:

• Studies on sleep duration and specific stroke types are limited.
• Existing research on sleep duration and stroke risk yields inconclusive results.
• Causality between sleep duration and stroke remains unclear.

Purpose of the Study:

• To investigate the association between sleep duration and the risk of stroke and its subtypes.
• To utilize both observational and Mendelian randomization designs for robust analysis.

Main Methods:

• A prospective study of 79,881 individuals (45-79 years) followed for stroke or death over 14.6 years.
• Mendelian randomization employed single-nucleotide polymorphisms associated with sleep duration.
• Genetic association data for stroke sourced from MEGASTROKE and International Stroke Genetics Consortia.

Main Results:

• Long sleep (≥9 hours) associated with increased risk of total and ischemic stroke.
• Short sleep (<7 hours) linked to higher risk of intracerebral hemorrhage.
• Mendelian randomization analysis found no causal association between short or long sleep and ischemic stroke.

Conclusions:

• Observational data suggest long sleep increases total/ischemic stroke risk, and short sleep increases intracerebral hemorrhage risk.
• Mendelian randomization analysis did not support a causal effect of sleep duration on total stroke or stroke subtypes.
• Further research is needed to clarify the complex relationship between sleep duration and stroke etiology.