Disturbances in sleep and rest patterns are a major health concern. This is because getting enough sleep is a fundamental aspect of human growth and development. However, a recent study found that getting more than eight hours of sleep may put an individual at risk of stroke. The said research published in Neurology also included a meta-analysis conducted in seven countries. Approximately over half a million participants were involved in the study, which found that long sleep hours can be fatal.

While poor quality sleep is associated with cognitive and physical impairments, insomnia was never found to cause premature deaths; this is according to a study conducted in the US involving more than 1.1 million individuals between 30 and 102 years old. Researchers are looking at regularly too short or too long hours of sleep to be the cause of the bigger problem, which is the association of sleep patterns with the occurrence of stroke.

The authors of the research conducted the study for more than nine years - monitoring the participants’ sleep duration and quality, and interviewing them twice every four years. The main goal of the study, which involved 10,000 people aged between 42-81 years, is to determine which sleeping pattern would most likely cause stroke.

The results of the study revealed that people who sleep for more than eight hours a day has 45 per cent risk of developing stroke. Conversely, those who sleep for less than six hours only has 19 per cent risk. The quality of the sleep, whether short or long in duration, does not impact these numbers. The research then concluded that morbidity and mortality associated with stroke are not highly influenced by the quality of sleep; it is the duration of the sleep that is playing the most important role.

The Neurology paper, however, adds that sleep disorders such as obstructive sleep apnoea, which is common in long sleepers may have a significant impact to the result of the study. According to previous research, 72 per cent of patients who survived stroke are diagnosed with sleep apnoea. This results in the person having light sleep because of the constant shift from deep to light sleep so as to facilitate breathing. Patients with sleep apnoea who have not received medical treatment are said to have longer but lighter sleep.

These data signify an association with stroke occurrence and sleep; however experts are still confirming about the exact roles that each factor plays. Furthermore, the authors of the Neurology paper said the study involved a mixture of individuals with and without comorbidities, and so they cannot affirm earlier research stating that other physical conditions are related to long sleeps.

Although a strong clinical premise has been established after the study, the authors iterate that further investigation is imperative. A number of different factors should be looked at before a conclusive association between long sleeps and stroke can be confirmed. Of course, individual risk factors should also be considered before recommending people to change their sleep routine.

The National Sleep Foundation based in the US recently released a revised guideline of recommended sleep hours. According to 18 sleep experts and review of over 300 studies, people aged between 18-65 years should have seven to nine hours of sleep in a 24-hour period, whilst those aged 65 should have sleep narrower than the seven to nine hour-band.

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