Connection Between Sleep Apnea and Memory Loss

Sleep apnea is a relatively common disorder that impacts the quality of your sleep. The most common form of this sleep disorder is obstructive sleep apnea (OSA). It is estimated that around 1 billion people across the globe have OSA, a disorder that results in sleep deprivation and excessive daytime tiredness.

Without treatment, sleep apnea increases the risk of heart disease, high blood pressure, stroke, and diabetes. Also, studies show that the disrupted sleep caused by OSA can also affect your cognitive processes and increase the likelihood of memory loss.

Why Sleep Is Important for Memory Function

Sleep is an important restorative tool. This includes our ability to remember. When you sleep, the brain uses the downtime to consolidate information processed during the day. This helps you memorize the information, enabling you to recall it at a later point.

The brain also uses this period to clear out the pathological proteins that accumulate throughout the day. The build-up of these proteins has been linked to dementia. 

We can all appreciate how just a single night of poor sleep can make you a little fuzzy-headed. You struggle to concentrate and can find it harder to remember certain things. Therefore, it stands to reason that a disorder that negatively affects your sleep night after night could significantly magnify the impact.

What Is Obstructive Sleep Apnea and How May It Affect the Memory?

Obstructive sleep apnea (OSA) is a condition that involves muscles in the throat while you sleep. The breathing difficulties resulting from the partial or complete blockage of the airways prompt the brain to wake the body for air. Sometimes you may awake gasping for air.

The word “apnea” refers to a temporary pause in breathing. Someone with severe OSA can experience over 30 apneas every hour. You may only awake for a few seconds each time and may not even realize this is happening. However, the cumulative effects of such disrupted sleep can have a serious impact not only on your body but your memory too.

As we have established, the brain needs sleep to consolidate memories. OSA denies the ability to receive consistent deep sleep, impacting the processing of memories. The extent of the memory loss could depend on the severity of your sleep apnea.

Research links OSA to mild cognitive impairment, where your memory issues start to become apparent to others. Studies report those with sleep apnea being diagnosed with mild cognitive impairment 10 years earlier than those who do not have a sleeping disorder.

Is There a Link to Dementia?

As well as mild cognitive impairment, it has long been suspected that a disorder such as obstructive sleep apnea could be linked to dementia. As mentioned, one of the restorative functions carried out while we sleep is the clearing out of proteins accumulated in the brain during the day.

The accumulation of these proteins is viewed as a risk factor for dementia. A sleep disorder that causes fragmented sleep could mean you are not getting the deep sleep needed to successfully remove all these proteins from the brain.

More research is required to ascertain a definite link. However, a recent study highlighted that damage begins in the same area of the brain for both sleep apnea and Alzheimer’s, the most common form of dementia. This hints that the two conditions are linked, which has long been suspected.

OSA is Treatable

It is estimated that approximately 40% of cases of dementia may result from modifiable risk factors. As OSA can be treated, sometimes with changes in lifestyle for a mild to moderate degree of the disorder, it can be classed as one such modifiable risk factor.

There is the prospect that treating your sleep disorder could make your risk of dementia modifiable – so recognizing the symptoms of OSA is key.

The Symptoms of Obstructive Sleep Apnea

One of the primary symptoms of OSA is frequent awakenings for air when the airways become blocked. As these micro-arousals can last for just a matter of seconds, it is often a bed partner who first notices them. Further symptoms of OSA include:

  • Excessive daytime tiredness
  • Loud snoring
  • Morning headaches
  • Dry mouth in the morning
  • Poor concentration
  • Irritability

The large majority of OSA cases go undiagnosed, leaving people at an increased risk of developing serious health issues linked to the disorder. As discussed, studies also point to the potential link between memory loss and dementia.

Although loud snoring is a primary symptom for OSA, just because you snore does not mean you have sleep apnea. However, if you are displaying any of the listed symptoms, it is worth discussing the possibility of having the sleep disorder with your doctor. They can arrange a sleep test, and if diagnosed, can help recommend the appropriate treatment for the severity of your disorder.

Treating Obstructive Sleep Apnea

A leading treatment for OSA is continuous positive airway pressure (CPAP) therapy. This involves a device that delivers pressurized air through tubing to a mask worn while you sleep. The air helps to keep the airways open and prevents the breathing difficulties that disrupt your sleep.

Research into the effects of CPAP is positive. People using CPAP were reported as experiencing memory decline 10 years later compared to those whose OSA remained untreated.

A major risk factor for sleep apnea is obesity. Therefore, lifestyle changes including improved dietary habits and increased exercise can remove some of the excess tissues in the throat that collapse and block the airways when you sleep.

As some people struggle to adapt to wearing a mask with CPAP, they may be recommended an oral device instead that repositions the jaw and tongue as they sleep. This helps keep the airways open.

Treating your sleep disorder can see you get the restorative sleep you need. This allows the brain to carry out vital nighttime functions including consolidating memories without interruption from frequent micro-arousals due to obstructive sleep apnea.