A team of scientists, who conducted their studies on autopsied brain tissues, have recently come up with specific strong evidence to link sleep apnea and Alzheimer’s disease. These studies showed how the toxic protein aggregations, usually seen in patients with Alzheimer’s disease, seem to spread similarly in the brains of patients who are diagnosed with sleep apnea.
This leads to the conclusion that if someone has sleep apnea in their mid-life, they are more likely to succumb to Alzheimer's when they get older. Likewise, if someone has Alzheimer's, they are more prone to developing sleep apnea in their life when compared to other people in their age group. Such a conclusion creates a dilemma regarding whether sleep apnea is a separate risk factor or is an early symptom of Alzheimer’s.
Although none of the subjects in this new study was clinically diagnosed with dementia or Alzheimer’s at the time of their death, this doesn’t prove that they were not having very early signs of Alzheimer's. On the other hand, some of those subjects may have shown undiagnosed dementia along with mild cognitive impairment even though none of them had strong enough symptoms for a positive diagnosis of Alzheimer's disease. Additionally, in mild sleep apnea cases, researchers found the toxic proteins only in the cortical area near the hippocampus of the brain. This is the exact area where they are first found in Alzheimer's disease. Those with severe sleep apnea had more significant amounts of toxic protein aggregations piled up in their hippocampus than mild cases did, regardless of the person's age.
However, we can arrive at a solid hypothesis that explains how sleep apnea could accelerate the start of Alzheimer’s disease. For example, one of the main functions of deep sleep is to free the brain from toxic proteins. We know that people with sleep apnea often fail to achieve this deep sleep level as they are continuously interrupted during their sleep. This means they become more prone to develop Alzheimer's disease.
However, researchers admit that even though this research solidifies our understanding of the links between cognitive decline and sleep apnea, it is still too early to confirm anything because the sample size was limited. Further challenges also remain unclear, such as translating these findings into clinical treatments for preventing cognitive decline.
As the next stage of the research, the samples will be reanalyzed to understand the neuropathology of the subjects thoroughly. This will include analyzing whether there are changes to the blood vessels that supply blood to the brain or any other inflammation signs.
If you are experiencing sleep apnea symptoms and are concerned about the link between Alzheimer’s and sleep apnea, please contact Urbandale Smiles today. We provide sleep apnea treatment at our clinic.