SLEEP DEPRIVATION AND THE RISK OF STROKE: A SYSTEMATIC REVIEW

Abstract

Background: Stroke is the second and third leading cause of death and disability worldwide, respectively, with a rapidly rising burden in low and middle income countries. Sleep distrubance, wheter inadequate sleep duration, poor sleep quality, insomnia, or obstructive sleep apnea (OSA), has been extensively studied as a potentially modifiable risk factor for stroke. This review summarizes current epidemiological and mechanistic evidence on the relationship between insufficient sleep and stroke risk.   Method: A systematic literature search was conducted across PubMed/MEDLINE, Science Direct, Frontiers, Nature, PMC, and Cochrane Library, using combinations of the terms “sleep duration”, “sleep deprivation”, “insomnia”, “obstructive sleep apnea”, and “stroke risk”, formalized into Boolean stratergy reported in the Method section. Eligible studies comprised meta-analysis and systematic reviews of prospective cohort studies, and randomization studies. Results: Both short (<5-6 h/day) and long (>8-9 h/day) sleep duration were consistently associated with increased stroke risk in prospective cohort studies, with the lowest risk at approximately 7-7,5 h/night. Poor sleep quality, insomnia, and OSA were each independently associated with increased stroke risk, with OSA showing the strongest and most mechanistically consistent effect. However, randomization studies have not consistently demonstrated a causal relationship between sleep duration and stroke risk. Conclusion: Available evidence supports inadequate sleep in duration and quality as a risk marker, and plausibly a modifiable risk factor, for stroke, although definitive causality still requires confirmation through intervention and genetic studies. Screening for sleep disorders, particulary OSA and chronic insomnia, was consider as a part of primary and secondary stroke prevention strategies.