Alzheimer’s and Sleep Apnea
In a 2013 study directed by John’s Hopkins University, scientists determined that poor sleep habits can be a cause of Alzheimer’s Disease (ALS). Moreover, this same study concluded that lack of sleep can advance progression of the disease. The study was started by previous research, which postulated that sleep was essential to the elimination of waste-like buildup that accumulated in the brain called “cerebral waste.”
The research patients involved in the Hopkins study were between the ages of 53 and 91. Patients that continuously reported poor sleep showed a disproportionate amount of beta-amyloid in areas of their brain. Beta-amyloid is a compound substance that has been directly linked as a definitive indicator of ALS.
Sleep is important for storing memories. It also has a restorative function. Lack of sleep impairs reasoning, problem-solving, and attention to detail, among other effects. However, the mechanisms behind these sleep benefits have been unknown.
Apnea and Alzheimer’s
Glymphatic system and Brain Cleaning
Cerebrospinal fluid, a clear liquid surrounding the brain and spinal cord, moves through the brain along a series of channels that surround blood vessels. The system is managed by the brain’s glial cells, and is called the glymphatic system. This system barely functions when you are awake but is very active while you sleep.
The glymphatic system helps remove a toxic protein called beta-amyloid from brain tissue. Beta-amyloid is well-known for accumulating in the brains of patients with Alzheimer’s disease. Other research also shows that brain levels of beta-amyloid decrease during sleep. Thus, the constant arousal of sleep in Sleep Apnea patients can hinder the glymphatic systems clearing of beta-amyloid.
Decrease Alzheimer’s with Sleep Apnea treatment?
In a landmark study, subjects were categorized as being free of memory and thinking problems, or in the early stages of mild cognitive impairment, or with Alzheimer’s disease. The scientists found that sleep apnea was associated with a much quicker decline in cognitive function. However, treatment for sleep apnea seemed to be protective, delaying the onset of mild cognitive impairment by approximately 10 years.
This meant that people who got treated for sleep apnea declined mentally at the same speed as people who didn’t have apnea at all.
Alzheimer’s disease and obstructive sleep apnea are highly prevalent, chronic conditions with fascinating, yet poorly understood epidemiological overlap.
Patients with Alzheimer’s disease have a five times higher chance of presenting with obstructive sleep apnea than cognitively non-impaired individuals of similar age.
Half of patients with AD have experienced OSA at some point after their initial diagnosis. The additive impact of progressive changes in sleep quality and structure, and changes in cerebral blood in OSA patients may all be contributing factors to cognitive decline and may further aggravate AD progression.
Patients with sleep apnea were, on average, diagnosed with mild cognitive impairment (MCI) nearly 10 years earlier than those who didn’t suffer from breathing problems during their slumber. Furthermore, the timespan for developing Alzheimer’s also seemed to speed up: Those with sleep apnea were diagnosed, on average, five years sooner than sound sleepers.