SEOUL, Jan. 4 (Korea Bizwire) – A joint study by doctors from the National Cancer Center and Myongji Hospital revealed that longer sleep duration can increase the risks of cognitive decline, resulting in diseases like Alzheimer’s.
According to the team, which compared and analyzed ten previous observational epidemiological studies on sleep duration and cognitive functions, those sleeping between 8 and 9 hours a day had a 38 percent and 42 percent higher risk of developing cognitive disorders and Alzheimer’s, respectively, compared to those sleeping 7 to 8 hours.
The same was observed in a subgroup analysis by specific factors like gender, region, age, study design, methodological quality of study, which were consistent in showing that long sleep duration can increase the risks of declining cognitive functions, the team noted.
“There have been studies that suggest sleeping too little or too much can increase the risks of Alzheimer’s or other cognitive disorders,” said Dr. Myung Seung-kwon from NCC, who took part in the study. “This was the first study of its kind that combined all the separate researches and studies.”
Although the clear relationship between long sleep hours and cognitive disorders has not yet been discovered, Myung suggested that sleeping for longer periods of time could increase the prevalence of inflammation-related biomarkers, thus promoting neural reactions that can result in diseases like Alzheimer’s.
“Having to sleep long hours could be a result of diseases like obstructive sleep apnea syndrome that can trigger cognitive disorders, or simply be an early symptom of the disorders,” he said.
In relation to the latest study, the team also added that the National Sleep Foundation recommends 9 to 11 hours as the ideal duration of sleep for children (aged 6 to 13); 8 to 10 hours for teenagers (14 – 17); 7 to 9 hours for adults (aged 18 – 64); and for those aged 65 and older, 7 to 8 hours.
“The study needs further research, but cutting down sleep time by an hour could be an option to consider for preventing Alzheimer’s,” said Myung.
The full research findings were published in the academic journal Neuroepidemiology in December 2016.
By Kevin Lee (firstname.lastname@example.org)