How does sleep affect your heart?

Many studies have linked poor sleep to an increased risk of heart disease. We look at how sleep and sleep disorders affect your heart health and find out how much sleep is ideal.

Woman and man sleeping in bed

An extra hour’s sleep isn’t the only upside of putting your clock back on Saturday night, for the following couple of days you may also be at a lower risk of a heart attack.

An American study found that a few days immediately after the return to standard time, there was a reduction in the number of people presenting with heart attacks at emergency departments. Likewise, when the clocks went forward in spring they saw an increase in the number of heart attacks. The findings are similar to those seen in 2008 research carried out in Sweden.

The researchers in both studies suggested that the changes in risk might be related to changes in sleep, a theory that fits with a growing body of evidence linking sleep problems and cardiac health.

A 2016 report from the American Heart Association concluded that both too little and too much sleep, and sleep disorders such as insomnia and sleep apnoea, were associated with increased risk of heart disease, even when adjusting for other risk factors such as weight, smoking, age and ethnicity.

Why does bad sleep increase heart disease risk?

Unfortunately, researchers are unsure as to exactly why too little sleep is bad for your heart health, although they do have some theories.

Ongoing sleep deprivation has not only been associated with high blood pressure (hypertension), a known risk factor for heart disease, it’s also been linked with higher levels of chemicals linked to inflammation. Although it hasn’t been proven that inflammation causes heart disease, higher levels of inflammation are common in people living with the condition.

How do sleep disorders like insomnia and sleep apnoea affect my heart?

One way that clinicians know a link exists between sleep and heart conditions is because people with sleep apnoea are more likely to experience heart disease.

When someone has sleep apnoea their breathing pauses for short periods while they are sleeping. These pauses, which can occur 30 times or more times an hour, cause the person to wake as they gasp for air. This in turn prevents a restful night’s sleep.

Sleep apnoea is strongly associated with high blood pressure, irregular heart beats, coronary artery disease and heart failure.

The American National Commission on Sleep Disorders Research estimated that obstructive sleep apnoea may account for 38,000 cardiovascular deaths in the US each year.

An increasing number of studies are also showing links between insomnia and the risk of heart disease.

The good news is there are ways to treat sleep disorders, so talk to your doctor if you’re struggling with sleep.

How much sleep is best for my heart?

Unfortunately, there’s debate amongst experts about exactly how much sleep is ideal.

For ‘optimal health’ the American Academy of Sleep Medicine recommends seven of more hours of sleep per night for adults. While the American Heart Association suggests seven or eight is ideal. Meanwhile a study presented at the 2018 European Society of Cardiology conference suggested that between six and eight hours of sleep a night is the ideal for heart health.

So, seven to eight hours sleep is probably a good target.

How do heart conditions affect my sleep?

Of course, getting the ideal amount of sleep can be easier said than done, as anyone who has experienced insomnia knows only too well. Sometimes a heart condition can also negatively impact the quality of your sleep.

While you probably can’t cure your heart condition, there are some steps you can take towards getting a better night’s sleep.

In this article on dealing with sleep problems psychologist Marie Young talks about disruption in sleep after a heart event and provides top tips for getting a better night’s sleep.

Will sleeping tablets affect my heart condition or my heart pills?

For those still struggling to get a good night's sleep, you may also look to pharmaceutical or complementary medicines for help.

However, some medication for insomnia isn’t safe for people with certain heart conditions, so it’s important to mention your heart condition and treatment to your health professional when you’re talking about sleeping tablets.

It’s also possible that certain sleeping pills (either prescribed or over-the counter) could interact with your heart medication. Once again, talk to your doctor or pharmacist before starting any medication to help you sleep.

Ways to deal with sleep problems

BMJ Journals Daylight savings time and myocardial infarction

New England Journal of Medicine Shifts to and from Daylight Savings Time and Incidence of Myocardial Infarction

Circulation: Sleep Duration and Quality: Impact on Lifestyle Behaviours and Cardiometabolic Health: A Scientific Statement From the American Heart Association

American College of Cardiology Insomnia and Heart Disease

Centre for Disease Control and Prevention data statistics

National Sleep Foundation: How sleep deprivation affects your heart

European Society of Cardiology: Finding the sweet spot of a good night’s sleep

Annals of Behavioural Medicine. Sleep and inflammation: psychoneuroimmunology in the context of cardiovascular disease.

Journal of Sleep Medicine. Sleep and future cardiovascular risk: prospective analysis from the English Longitudinal Study of Ageing

Journal of Sleep Medicine: Obstructive Sleep Apnea and Cardiovascular Disease: Role of the Metabolic Syndrome and Its Components