In an analysis of the sleep habits of over 72,000 people, researchers identified a particular pattern that can dramatically spike the risk of major cardiovascular problems. The good news is that the pattern is relatively easy to avoid.
You've always known it, and science continually proves it: getting sufficient sleep is important for good health. Lack of quality shut-eye has been linked to an increase in women's risk of heart disease, elevated pain symptoms, more of a chance of developing dementia, and more.
Researchers are now starting to focus not only on how much sleep you get, but the form that sleep takes. For example, studies have found that getting too much sleep can impair cognitive functions, while going to bed and waking up at inconsistent times has been associated with high blood pressure, obesity and other metabolic disorders.
Perhaps it's no surprise then, that researchers in Australia and Canada have just revealed that irregular sleep patterns raise the risk of getting some types of cardiovascular disease – including heart attack, heart failure and stroke – by 26%.
The researchers looked at 72,269 people aged between 40 and 79 who have taken part in the UK Biobank study, a massive database of genetic, lifestyle and health information from over 500,000 UK participants. None of the participants selected had a previous history of major cardiovascular events.
All participants wore an activity tracker for seven days. The data gleaned from those devices was then used to create a sleep regularity index from (SRI) from 0-100 based on variability in bedtime, wake times, sleep duration, and how many times someone awoke during the night. People with SRIs above 87 were considered to have a regular sleep pattern, and those with scores below 72 were considered irregular sleepers. Those in between the two scores were considered moderately irregular sleepers.
Once classified as a regular, moderately irregular or regular sleeper, the participants were then monitored for the next eight years for incidents of heart attack, heart failure, stroke and cardiovascular-related death. Not only did the analysis determine the 26% increased risk for irregular sleepers, but moderately irregular sleepers were shown to have an 8% increased risk of major cardiovascular disease.
In the calculations that led the researchers to their conclusions, a broad range of factors that could potentially influence cardiovascular health were accounted for, such as smoking, medication use, coffee and alcohol intake, mental health issues, shift work, and more.
Enough is not enough
The researchers also looked at sleep duration and how it compared to the generally recommended times: 7-9 hours for people 18 to 64 years old, and 7-8 hours for those above age 65. Interestingly, they found that even those who hit this target amount of sleep, but had irregular sleep habits, still suffered from the increased health risks. So getting enough sleep wasn't enough, the key was getting regular periods of sleep that didn't alter much from day to day.
"More attention needs to be paid to sleep regularity in public health guidelines and clinical practice due to its role in cardiovascular health," write the researchers in a paper published in the Journal of Epidemiology & Community Health. Future studies are needed to explore whether interventions aimed at improving sleep regularity might improve cardiovascular health.
Source: BMJ Group via Scimex.org