Nearly one billion people worldwide have sleep apnea1, a disorder that can cause you to periodically stop breathing and experience micro-awakenings when you are sleeping. Medical professionals have long known that this disorder can lead to health complications2 such as poor sleep, strokes, heart attacks, problems with certain medications and general anesthesia, and glaucoma.
However, new research is shedding light on another complication of this sleep disorder. The 2023 study3, from the American Academy of Neurology, has found that uncontrolled sleep apnea and less deep sleep as a result of sleep apnea can also worsen your brain health.
What the Study
The study observed 140 participants from the Mayo Clinic Study of Aging. The average age for those in that study was 72 and the cases of mild, moderate, and severe sleep apnea were divided nearly equally among them. None of the participants had dementia, but they had all undergone magnetic resonance imagining (MRI) scans.3
These MRI scans were used to study their white matter damage, also referred to as white matter hyperintensities4. In addition to looking for hyperintensities, the researchers also evaluated the biomarker that measures the movement of water inside fibers that connect neurons to the brain.3 This was used to measure early-stage white matter abnormalities that are associated with vascular disease, which has been considered a leading cause of dementia5.
When looking at this biomarker, the researchers factored out conditions associated with changes in the brain such as age, cholesterol levels, and blood pressure. The results showed that those who only had 5 percent of their total sleep happen during slow-wave sleep looked more than 4.5 years older when it came to white matter abnormalities than those who got 25 percent of their rest in deep sleep.3
It should be noted that the association between sleep apnea and hyperintensities was only shown in severe cases. This, according to the researchers, suggests that mild to moderate sleep apnea may not cause white matter abnormalities.3
Why Is This Research Important?
This study suggests that a lack of slow-wave sleep caused by severe sleep apnea can have significant impacts on your brain health when compared to those who spend more time in deep sleep.3
Slow-wave sleep is when the body restores itself and boosts your energy and immunity6, but it is also when you rid yourself of beta-amyloid7, a marker for Alzheimer’s. Therefore, getting enough deep sleep is an essential step in flushing out beta-amyloid and reducing your risk of Alzheimer’s.
Additionally, the study presented that those who had less deep sleep showed faster brain aging.3 This brain aging may cause a lag in your ability to process information8, along with other memory issues.
While getting adequate deep sleep is important for helping to prevent dementias like Alzheimer’s, it’s also essential for boosting everyday brain health. For example, those who aren’t getting enough deep sleep are likely to have a harder time paying attention during the day, which can impact school or work performance, as well as the ability to safely drive or operate machinery.
When white matter damage occurs due to lack of quality sleep (or other causes), healthcare providers focus on managing symptoms9 as this has been shown to slow the progression of white matter damage. These preventative steps to help control white matter damage can include9:
Considering we also know that sleep apnea and poor sleep quality are linked to high blood pressure, heart attacks, strokes, and more, it is essential to manage apnea symptoms and prioritize good sleep.2
Sleep Apnea Treatments
- Weight Loss – Obstructive sleep apnea is most often seen in overweight or obese10 people because additional weight leads to fat deposits in the neck that can block your airway when you are sleeping. Therefore, weight loss could help alleviate symptoms.
- Continuous Positive Airway Pressure (CPAP) – If you have been diagnosed with sleep apnea after a polysomnography, your medical professional may prescribe a continuous positive airway pressure (CPAP) device. These machines provide continuous air pressure that reduces the number of times that you stop breathing from obstruction. CPAP therapy is available by prescription only.
- Oral Appliances – Those with mild or moderate sleep apnea may find that an oral device that keeps your throat open may help you get more deep sleep. These mouthpieces work by either bringing your lower jaw forward or by holding your tongue in a different position. A dentist will need to fit you for one of these.
- Surgery – There are a variety of surgeries11 that can help eliminate obstructions, including those that remove tissue from the back of the mouth and the top of the throat and ones that move the jaw forward. If other treatments and surgeries have failed and you have life-threatening sleep apnea, a surgeon may perform a tracheostomy, a procedure in which a surgeon makes an opening in the neck and inserts a tube that provides unobstructed air passage.11
Tips for Getting More Deep Sleep
- Create a relaxing sleep environment – A cool, dark, and quiet room is optimal for sleeping.
- Stick to a schedule – Keep your body’s circadian rhythms in sync by going to bed and waking up at the same time every day.
- Invest in a quality mattress – Find a great mattress that supports your body type and preferred sleep position to allow you to rest more comfortably.
- Avoid screens before bed – A phone or tablet’s blue light can hinder melatonin production12 and make it harder to fall asleep. Instead, try to cut off your screen time at least 30 minutes before bed, though ideally an hour.
- Get physical – Daily exercise and general physical activity can promote better sleep12. However, avoid doing any vigorous exercise too close to bedtime. If you have to exercise later at night, try workouts like pilates, yoga, or stretching.
- Be mindful of what you eat and drink – The foods we put into our bodies can either either help or hinder our sleep. In this case, try to avoid spicy or fatty foods that may cause acid reflux, and avoid eating too much late at night as this could lead to indigestion. Limiting alcohol and caffeine can also help you sleep more soundly.
- Limit daytime naps – Daytime naps can be refreshing and restorative, but they can also wind up interfering with your nighttime sleep. Ideally, you should avoid naps if you can, but if you absolutely need one, keep it to a maximum of 30 minutes and avoid napping past 3:00 p.m.
- Establish a calming nightly routine – A relaxing nighttime routine can help you wind down at the end of the day. This may include a shower or bath, drinking herbal tea, reading a book, or doing some light stretching.
Sleep is one of the most important components of our overall health. It is particularly important that we get enough deep sleep so that our body can restore itself, and we can function to the best of our abilities the next day. Those with severe cases of sleep apnea often don’t get enough slow-wave sleep because they can wake dozens of times a night, but as research shows, less slow-wave sleep has been shown to worsen brain health and potentially lead to life-threatening issues.
If you think that you may have sleep apnea, it is imperative that you consult your healthcare provider to find the best treatment plan for you.
Sosha Lewis is a staff writer for Sleep Advisor. Lewis is happy that she is able to combine her love of sleep with her love of writing.
- Benjafield, Adam V., et al. “Estimation of the global prevalence and burden of obstructive sleep apnoea: a literature-based analysis”. National Library of Medicine. 2019.
- “Obstructive Sleep Apnea: Symptoms & causes”. Mayo Clinic. Last modified July 14, 2024.
- Carvalho, Diego Z., et al. “Association of Polysomnographic Sleep Parameters With Neuroimaging Biomarkers of Cerebrovascular Disease in Older Adults With Sleep Apnea”. American Academy of Neurology. 2024.
- Merino MD, José G. “White Matter Hyperintensities on Magnetic Resonance Imaging: What Is a Clinician to Do?”. Mayo Clinic. 2019.
- Kling MD, Mitchel A., et al. “Vascular Disease and Dementias: Paradigm Shifts to Drive Research in New Directions”. National Library of Medicine. 2013.
- “How sleep boosts your energy”. Harvard Medical School. 2020.
- “What Happens to the Brain in Alzheimer’s Disease?”. National Institute on Aging. Webpage accessed September 29, 2024.
- Gunning-Dixon PhD, Faith M., et al. “Aging of Cerebral White Matter: A Review of MRI Findings”. National Library of Medicine. 2009.
- “White Matter Disease”. Cleveland Clinic. Last modified May 4, 2022.
- Romero-Corral MD, Abel., et. al. “Interactions Between Obesity and Obstructive Sleep Apnea.” National Library of Medicine. 2020.
- “Obstructive sleep apnea: Diagnosis & treatment”. Mayo Clinic. Last modified July 14, 2024.
- “Blue light has a dark side”. Harvard Health. 2020.