The study on links between self reported sleep duration and quality with cardiovascular outcomes and mortality across 74 studies which included upwards of 3 million people also found that sleeping for over 10 hours is associated with 30% increased risk of dying compared to sleeping 7 hours or less; and sleeping for ten hours was found to have increased risk of death from stroke by 56%, and risk of death from cardiovascular disease by 49%.
The study began out of interest of knowing whether it was more harmful to sleep beyond or below recommended sleep duration of 7-8 hours per night, and if incremental deviation altered risk of mortality and cardiovascular risk. Findings have important implications for the public to show that too much sleep can be a bad thing, and clinical implications suggesting doctors should ask more about sleep duration and quality when talk to patients according to the scientists.
Results suggest sleeping longer than 8 hours could be linked to moderate degree of physical damage. Longer sleep duration is associated with increased risks due to comorbidities leading to fatigue such as anaemia and chronic inflammation. Abnormal sleep is a marker for poor health, elevated cardiovascular risk, greater consideration should be given when exploring sleep duration and quality during consultations, says Chung Shing Kwok of Keele University.
