Sleep & heart age: what is the recommended duration

Is your heart older than you think?

And if so, what can you do to... keep it young and avoid increased cardiovascular risk?

"Age of the heart" is a concept scientists use to describe the biological damage that occurs in the heart that increases the risk of heart attack, stroke and other cardiovascular complications.

Factors that promote biological ageing of the heart include hypertension, excess body weight and an unhealthy diet.

According to a new scientific study conducted by researchers from the American Academy of Sleep Medicine (AASM), sleep also appears to play a key role in the rate of heart aging.

The 7 hours of sleep "elixir of youth" for the heart

As part of their study, the researchers followed 12,775 adults aged 30-74 years. Participants had to indicate how many hours they slept on average per night (5 or less, 6, 7, 8, 9 or more) and their heart age was calculated using a special algorithm.

Based on the data collected and analysed by the researchers, they calculated how many of the participants had an older heart or were at risk of premature heart ageing based on their sleep duration.

The "magic" number appeared to be 7, since those participants who said they slept an average of 7 hours a day were the ones who had the "youngest" hearts or were less at risk of cardiovascular complications due to premature aging of their hearts.

Both shorter and longer sleep duration, the researchers note, was associated with more chances of premature heart aging and, by extension, various heart problems. Those who slept very few hours in a 24-hour period appeared to be at greater risk, of course, compared with those who enjoyed more than 7 hours of sleep a day.

"These results are important as they show how sleep can be included as a parameter in the calculation of cardiovascular risk," says Julia Darmer, a member of the research and editorial team that carried out the study.

The abstract of the study is published online in the journal Sleep, and the findings were presented in detail at the 32nd Annual Meeting of the Societies for the Study of Sleep (SLEEP 2018) in Baltimore, USA.