We know that sleep apnea is associated with an elevated risk of developing Alzheimer’s disease and other forms of dementia. Not only that, it’s associated with a risk of developing dementia early.
There’s enough evidence that we are confident there is a causal link, although this hasn’t been firmly established. We also haven’t firmly established whether treating sleep apnea can reduce or eliminate dementia risk associated with sleep apnea. But now a new study could change that, giving us definitive answers about the link between sleep apnea, dementia, and treatment.
A Large, Long-Term Study
To definitively answer questions about causation and prevention, studies have to meet two main criteria: they have to be large enough to give statistical significance, and they have to be long enough to establish the causal links.
How large does the sample size need to be? Ideally, we would want to see something with a sample size over 1000, but realistically this study will most likely have only a few hundred people.
How long does the study have to be? That depends on the length of time that it may take for the disease to manifest. In the study announcement, researchers note that it may take 10 years for sleep apnea to cause the development of Alzheimer’s disease, so they’re probably targeting a study length about that long.
A recent study of about 200 people with a two-year follow-up showed that sleep apnea increased amyloid beta levels (more on this soon), but didn’t increase dementia symptoms. Ideally, this new study should have a larger population and be longer to really answer these questions.
What’s the Cause?
Hopefully, one of the questions this study will answer is how, exactly, sleep apnea causes dementia. Most of the evidence we have seen suggests that amyloid beta is the link, but the researchers in this study propose a different link.
Amyloid beta plaques are a common feature of Alzheimer’s disease. It’s been shown that one of the functions of sleep is allowing the brain to clean out amyloid beta, thereby reducing the risk of dementia. It’s been proposed that the sleep interruptions caused by sleep apnea prevent the brain from effectively cleaning itself. And it’s been shown that the more sleep interruptions you have, the higher your levels of amyloid beta.
However, researchers from this study propose that it’s actually the decreased oxygen levels that cause the dementia. They say that higher levels of oxygen deprivation kills brain cells, leading to higher dementia risks.
A Flaw in the Study Design
One disappointing fact about the study is that it seems to be focused on the use of CPAP to treat sleep apnea. This doesn’t make sense, given that oral appliances are as effective as CPAP at relieving psychological symptoms of sleep apnea. Limiting the study introduces the confounding factor of CPAP compliance, which means that the population will have to be even larger to account for the fact. Hopefully, if an individual is assigned to the treatment group, they will be given the option of taking advantage of oral appliance therapy, so they can continue to get treatment and help maintain the statistical significance of the study. Otherwise, we may end up with more studies like those showing CPAP doesn’t help heart patients.
Treat Sleep Apnea Today
We already know that there are many great benefits to treating sleep apnea. It can reduce your risk of car accidents, drop your blood pressure, and reduce or eliminate your daytime sleepiness. Evidence suggests that it will also reduce your risk of dementia.
To learn more about your sleep apnea treatment options in Omaha and how they can benefit you, please call (402) 493-4175 today for an appointment with a sleep dentist at the Advanced Dental Sleep Treatment Center.