Left untreated it can lead to strokes, heart failure and death.
Yet atrial fibrillation (AF) — the most common form of irregular heartbeat — is forecast to grow to epidemic proportions within the next decade or two as the population ages.
One of the risk factors for AF is sleep apnea, a condition in which a person wakes up frequently, gasping for breath, because of repeated short blockages in breathing.
But is sleep apnea a specific risk factor for AF or can this cardiovascular problem be caused by poor sleep in general? If the latter, an abnormal heartbeat would be a more serious matter that affects everyone who doesn’t sleep well through the night. That comprises a huge number of people.
The emerging science has already proven that the inability to sleep well through the night is a major cause of dementia. If we now have to add heart disease to the list of medical problems that a bad night’s sleep makes worse, then sleep (or the lack thereof) stands forth as a personal medical crisis you need to solve.
A Consumer Reports survey of 4,023 adults found that more than one out of four had difficulties falling or staying asleep most nights of the week. We can see that confirmed by the fact that Americans spent $41 billion on sleep aids and remedies in 2015 alone.
Sleep Disruption Increases Risk of AF By 36%
To find out if insomnia increases the risk of AF, 17 scientists led by the University of California, San Francisco (UCSF), drew on data from four different studies.
In the first, of 4,553 volunteers, those who awoke from sleep more frequently had a greater likelihood of being diagnosed with atrial fibrillation.
In the second study, researchers followed 5,703 participants for 11½ years. Those reporting more frequent nighttime awakenings at the start of the study had a higher risk of developing AF in the years ahead, even after other risk factors were taken into account.
1,127 members of this group also took part in formal sleep studies. The ones experiencing shorter periods of rapid eye movement (REM) sleep had a higher risk of developing AF. Each reduction in REM sleep raised the level of risk. REM sleep has long been known to be essential to good health.
Finally, the researchers looked at a huge database of 14 million California residents over four years. They found that a medical diagnosis of insomnia predicted a 36% increased risk of newly diagnosed AF.
The study, which was published in Heart Rhythm in June, concluded that “Sleep disruption consistently predicted AF…” This was the first study to link poor sleep quality in general with a higher risk of AF.
The Importance of REM Sleep
The sleep cycle consists of five stages. Typically, it takes about 1½ hours to progress through all five. If you’re sleeping well, the cycle is repeated four to six times during the night. The last stage is REM. This is where most dreaming takes place and also where dreams are most vivid.
During REM the emotions and experiences of the day are processed. Psychologists believe this is vital for emotional and mental health. However that may be, we know for a fact it’s essential to physical brain health.
The dream phase is involved with creativity, problem solving, learning new information, sustaining key neural pathways, and processing memories. Perhaps most important, sleep is the time when toxins and waste products are removed from the brain. If you don’t sleep, the garbage doesn’t get taken out.
People who don’t get adequate amounts of REM sleep are more likely to feel unrefreshed when they wake up. They’re also more likely to experience daytime drowsiness and to be at a higher risk for neurodegenerative diseases like dementia.
The latest study now links disrupted and shorter REM sleep to a higher risk of atrial fibrillation. This in turn makes strokes and heart problems more likely.
According to lead investigator Gregory Marcus MD at UCSF’s Division of Cardiology, “While there are several available treatments for AF, prevention of the disease would be ideal. The good news is that sleep quality can be modifiable and is something that at least to some degree is under the control of the individual.
“It’s possible that improving sleep hygiene such as performing regular exercise, getting to bed at a reasonable hour on a regular basis, and avoiding viewing screens before bed as well as caffeine later in the day, might help stave off AF.”