Chronic sleep deprivation leads to accelerated biological aging besides increasing the risk of cardiovascular disease, said a Singapore-based team of researchers, after analyzing the data with the help of FitBit wearable trackers.
Many studies have already established that insufficient sleep is linked to poor health but for the first time a tracker has been used by researchers from the SingHealth Duke-NUS Institute of Precision Medicine (PRISM) and the National Heart Centre Singapore (NHCS), whose findings have been published in the journal Communications Biology.
The PRISM-NHCS team analysed the sleep patterns of Singaporeans using wearable FitBit trackers that collected data about the amount and quality of sleep one gets every day and its link to one's health and risk of heart disease. More than 480 volunteers have participated and submitted one week's sleep data for the study. In addition, the team also collected lifestyle information and data for cardiovascular disease risk factors such as blood pressure, cholesterol, blood glucose.
To estimate biological age, co-lead of the study, Asst Prof Lim Weng Khong, Chief Information Officer, SingHealth Duke-NUS PRISM and Assistant Professor, Cancer and Stem Cell Biology Programme, Duke NUS analysed the volunteers' whole-genome data to estimate their telomere lengths, which are compound structures of DNA at the end of the chromosomes in human cells that decline in length as one ages. Telomeres are believed to represent one's biological age, as opposed to chronological age.
Telomeres are also affected by external factors such as diet, exercise and lifestyle. Studies have often linked short telomere length to adverse health outcomes including increased cardiovascular disease risk. The team found that the seven per cent of volunteers who slept less than five hours a night were twice as likely to have shortened telomeres compared to those who exceeded the recommended sleep amount of seven hours. They also had increased cardiovascular risk factors such as higher body mass indexes and waist circumferences.
"What we found was that volunteers with enough sleep tended to have longer telomeres compared to those that did not. This was even after accounting for other factors such as age and gender, and provides evidence for a link between chronic sleep deprivation and premature aging," said Lim. The growing adoption of wearables in Singapore could help collection of health data from more volunteers, he noted.
Prof. Michael Chee, Principal Investigator, Centre for Cognitive Neuroscience at the Duke-NUS, who was not involved in the study, said that the findings are a reminder for Singaporeans to adopt better sleep habits. "East Asians as a group are the most sleep-deprived people in the world," he asserted.