New research confirms that good sleep is essential for cardiovascular health. Researchers have examined the relationship between cardiovascular risk and sleep quality. They found that better sleep quality is linked to lower cardiovascular risk. They noted that increased awareness of sleep quality and quantity might improve sleep quality and potentially reduce cardiovascular risk. Studies show that sleep disturbance is linked to multiple cardiovascular problems. Research also indicates that healthy sleep habits reduce cardiovascular risk, even in people with high genetic risk.
Most studies examining the link between sleep quality and cardiovascular risk have focused on a single dimension of sleep: sleep duration or sleep apnea. The combined effect of several dimensions of sleep on cardiovascular health therefore remains little studied. Recently, researchers from the National Institute of Health and Medical Research in Paris (France) studied the joint effect of several sleep habits on the incidence of cardiovascular disease. They found that an overall healthier sleep score was linked to a lower risk of cardiovascular disease and stroke. They presented their findings at the congress of the European Society of Cardiology.
The better the sleep, the lower the cardiovascular risk
For the study, researchers analyzed data collected between 2008 and 2011 from 7,203 men and women between the ages of 50 and 75. All did not suffer from any cardiovascular pathology at the start of the study.
Each participant underwent a physical examination and various biological tests. They also provided information regarding their lifestyle and medical history. The researchers assessed participants’ sleep patterns through a questionnaire, looking at:
sleep duration
insomnia
the early waking chronotype, known as the “morning person”.
sleep apnea
la somnolence diurne subjective.
A score of 1 or 0 was assigned to each dimension. The criteria for obtaining a score of 1 or a “healthy” score are as follows:
early chronotype
a sleep duration of 7 to 8 hours a day
little or no insomnia
no sleep apnea
no frequent daytime sleepiness.
Participants’ overall sleep scores therefore ranged from 0 to 5. Of the participants, 6.9% had a sleep score of 0 or 1, and 10.4% had an optimal sleep score of 5. After a median follow-up of 8 years, the researchers noted that participants with a score of 5, optimal sleep, had a 74% lower risk of cardiovascular disorders than those with the worst quality of sleep. They added that each one-point increase in healthy sleep score corresponded to a 22% reduction in cardiovascular risk.
What are the underlying mechanisms?
Current research suggests that healthy sleep is vital for resting the heart and brain. In the absence of sleep, there can be an increase in inflammation, a release of stress hormones, and a decrease in the removal of toxins from the brain. These phenomena can lead to fluctuations in heart rate and increased blood pressure during the night. We believe this can lead to heart conditions such as uncontrolled blood pressure: hypertension, irregular heart rhythms like atrial fibrillation and possibly poor cognition [ou] memory difficulties. Poor sleep, if secondary to underlying sleep apnea, can also lead to increased risk of stroke/blood clots through inflammation, as well as lack of oxygen la night and thickening of the blood, which results from chronic low oxygen levels in the blood.
The increased tone of the sympathetic nervous system is responsible for a greater circulation of catecholamines, which are hormones that cause an increase in heart rate, blood pressure and vascular resistance. Indirectly, poor sleep contributes to the dysregulation of hormones involved in hunger. This contributes to obesity, which is a significant risk factor for cardiovascular disease. The researchers concluded that better sleep quality across multiple dimensions is linked to a lower risk of cardiovascular disease and stroke.
Expert tips to improve sleep
Sleep experts recommend prioritizing sleep and that 7-8 hours of sleep per night is ideal for heart health.
It’s also important to practice good sleep hygiene, which is putting yourself in the best position to sleep well by optimizing your sleep schedule, bedtime routine, and sleep environment.
Stick to a stable sleep schedule, i.e. try to go to bed and wake up at the same time every day, and try to keep the same sleep schedule on weekdays and weekends to avoid disrupting the sleep-wake rhythm of your biological clock. Take advantage of the hour before bedtime to unwind and relax, and optimize your sleeping environment by making your bedroom comfortable, quiet, cool and dark.
Get rid of distractions like bright light and noise. For example, use heavy curtains or an eye mask to block light from interrupting your sleep, and avoid bright light sources like computers, televisions, and telephones. Also try to muffle any noise by using earplugs or a white noise machine, and avoid stimulants like nicotine and caffeine.
Finally, from a public health perspective, increasing health awareness and knowledge regarding sleep quality is essential. It might indeed start early in life, as early as primary school perhaps. This might represent a wonderful window of opportunity to learn early on how to practice good sleep hygiene.
