Can Sleep Apnea Cause Alzheimer's?

Thank you for your fascinating post Dr Park. My 70 year old father was recently diagnosed with early dementia. His mother (my grandmother) suffered a series of microstrokes when she was in her 60's onward until she descended into complete senility by the time she passed away at 83. My dad always was a big snorer, he has suffered from sleep apnea nearly his entire adult life. After reading what you've said here, I can't help but wonder if what is happening to him now has been caused or at least exacerbated by his longstanding sleep apnea. It makes sense - snoring deprives the brain of oxygen, and all of those accumulated "hypoxic episodes" over the decades are bound to take a toll. Is it possible the plaques and tangles seen in brain tissue samples from those with dementia were caused by a form of gradual brain cell death scarring? Similar to cirrhosis of the liver, except instead of damaged hepatocytes, it's being caused by brain cell death due to a long term oxygen deficit? (from sleep apnea and/or vascular obstructions due to arterial cholesterol/plaque etc?)

I'm now in my early 40's and of course the thoughts of how I might prevent dementia are on my mind. I'm a snorer too. Probably not as bad as my father, but I definitely experience sleep apnea from time to time (and the fatigue that comes with it). I'm thin and not overweight, I do not have a thick neck. I take good care of myself and exercise and eat reasonably well (including green tea, salmon, blueberries etc). I do have a strongly deviated septum which completely obstructs my left nostril. I also seem to experience some kind of low level allergy syndrome. My sinuses are almost always at least partially clogged and I often have red eyes (I do not regularly take allergy meds). This forces me to breathe through my mouth and I suppose cause my snoring. If I had my septum surgically fixed, and perhaps started taking allergy meds to reduce my sinus congestion, do you think this would help me? And do you think having my uvula surgically removed will help? Your words "All this goes back to my theory that all humans are on a continuum with regards to sleep-breathing problems" haunt me. I know what you're saying is true, it has to be. And I want to take corrective action sooner rather than later. Thank you for sharing your thoughts - god bless!

dude-o-rama,

There are many pathways where sleep apnea can cause stroke. Carotid artery plaque formation, or a heart arrhythmia can throw a large clot into the brain, leading to a major stroke. Another way is when blood flow is diminished, blood tends to clot—this will happen in the smaller end-vessels. The senile plaques and tangles could the be scar tissue formations. Your liver analogy is a good one.

One thing that's been proven is that you don't have to be overweight, male, or have a big neck to have sleep apnea. I have many young, thin, women in my practice that don't snore that have significant obstructive sleep apnea. You should see a sleep doctor and get tested and treated. Chances are, fixing your deviated septum will not cure your sleep apnea. Your sleep-breathing condition can also aggravate your nasal/sinus conditions and can sometimes present as allergy symptoms. Although having a stuffy nose can aggravate sleep apnea, the main source of your obstruction is typically your tongue (and less likely your soft palate/uvula). Only a thorough evaluation by an ENT that can look with a camera can tell where exactly these obstructions may be happening.

However, if you can't improve your nasal breathing through medications, I would recommend the nasal surgery. Breathing better through your nose is a good thing in general, and also will help you with your sleep apnea treatment (using a CPAP machine or a dental device). Take a look at my older articles on sleep apnea on this site. I talk about these issues more extensively in my book, Sleep, Interrupted.

Steven Y. Park. MD
www.doctorstevenpark.com

Thank you for your informative response Dr Park. Yes I strongly believe many thin people who do not fit the stereotypical overweight male with a thick neck profile can and do have sleep apnea. I actually went to a sleep doctor about 3 years ago and came in one evening for a sleep study (which was very expensive). They wired me up and I couldn't fall asleep almost during the entire evening! I only fell asleep about 20 minutes before the nurse had to wake me up in the mornining. So unfortunately no real data was collected on my sleep habits. But I know I have sleep apnea already, there is no doubt.

So clearing my sinuses and correcting my septum is unlikely to be largely curative? I guess I'll have to go see an experienced ENT as you suggest. I was really hoping to avoid being strapped to what appears to be a mechanical elephant every night (i.e. the CPAP machine). How often (statistically speaking) do simple dental devices work in alleviating sleep apnea? I'm not familiar with them, although I did see a tv commercial recently for them. Presumably they keep the tongue/jaw in the right place to keep the airway from collapsing in on itself?

I will take a look at your book. Sounds like it's right up my alley, thanks for the suggestion and the helpful advice. God bless...

dude_o_rama,

Sorry to hear about your sleep study experience. Although a formal study is ideal, another option for you is a home based study. They are much less expensive and less complicated. There's also a small chance that you could have a decent study and still not officially have obstructive sleep apnea. This is due to how we define an apnea. You have to stop breathing for 10 seconds or longer to say you had an apnea. The same goes for a hypopneas, where your airflow is significantly limited. You need 5 apneas or hypopneas every hour to say that you have obstructive sleep apnea. But if you stop breathing 25 times every hour and wake up after 1-9 seconds, then you're told you don't have sleep apnea.

It's understandable how you feel about using CPAP, but once you feel the benefits, you'll be hooked. But I have to warn you that it will be a process. Don't count on your sleep doctor and DME vendor (equipment company) alone to help you adjust to CPAP—you need to take responsibility for making sure that it works. For certain individuals that are candidates, a dental device is a good option. The over-the counter boil-and-bite models can help, but they are not adjustable. They are also bulky and uncomfortable. The custom-made devices (by dentists) are much more comfortable and adjustable (and more expensive). Success with these devices depends on the experience of the dentist and your willingness to give it an honest try. Surgery is also a reasonable option, but only as a last resort. With all three options, the rate of success ranges widely from 20-30% all the way to over 90%. It all depends. I talk about all these options briefly in my articles on this site and in more detail in my book. Good luck.

Hi there,
My husband was diagnosed with sleep apnea approximately 15 years ago.   He tried having laser surgery and had a dental appliance made - neither of them worked for him until he tried the machine.    The CPAP machine did take a little while to get used to but now he won't be without it.   He adds water to it every night and some nights the water tank is empty and other times only half empty.   His sleep pattern is much better however just about 3-4 weeks ago I have noticed him twitching in his sleep just before he actually falls asleep.    I have read all the comments about stress related factors and don't think this is his problem as he is fairly easy going and I know when he is under stress.   I'm wondering if it is because he has been diagnosed with a bleeding ulcer lately that this could also be the cause for the twitching.

This is a great forum and thank you.

Irishtwo

Dr. Park,

I would think that any method of increasing oxygenation to the blood is going to improve memory and performance.  To make a causal link, instead of an association or correlation, between sleep deprivation due to apnea and other sleep disorders, and diseases like Alzheimer's and MS, is, I think, taking quite a huge leap.  

To me it seems that in the case of MS and other auto-immune issues the cause OF sleep problems is the same mechanism that causes the MS, not the other way around, and that it is hematological and auto-immune in nature (and possibly genetic as well).  Treating the sleep and thus adding oxygenation helps in that it treats a symptom that then gives you better quality of life and may also slow the deterioration in the heart/blood vessels of any damage having to do with chronic insufficient oxygenation.

Let me give you an analogous example of what I'm talking about using an auto-immune disorder.  I have antiphospholipid syndrome.  It has affected several different organs (pre-discovery).  It has caused adrenal insufficiency, focal nodular hyperplasia, gall bladder insufficiency (possible infarct), chronic headaches, pre-eclampsia, miscarriages, thickening of the walls of vessels in my bowel and heart, pulmonary scarring, and many other issues I won't bore you with here.  Now that I have finally been diagnosed, I am on blood thinner.  The blood thinner both relieves my worst symptoms (the headaches in particular), and it keeps other problems from recurring or becoming worse (keeps more nodules of vessels from forming in my liver, more micro-hemorrhages of the adrenals - although, they are shot anyway, lol, and of other organs from occurring, helps the blood run through my vessels more easily, keeping them in better shape (I had chronic hypertension before treatment (diastolic) - I could go on and on.  What it does NOT do of course, is cure antiphospholipid syndrome.  It treats it.

I think what you have with the sleep issues and use of mechanisms like the cpap is exactly analogous.  That "system" controlling the manner in which one breathes at night, is damaged by MS in the same manner that MS damages other organs and systems, and I'll quote here from the MS resource center:

"Muscle weakness: as the muscles which control breathing weaken, the ability to cough is impaired and the patient is at a high risk of pneumonia and other complications in the lungs. Inactivity can result in such weakness, as can poor postural alignment and trunk control, muscle imbalances, decreased bone density, and/or shallow, inefficient breathing."

So MS can cause structural changes as well as causing postural issues during sleep - not to mention the potential for infection.  The same muscular issues faced elsewhere in the body due to MS apply here, as well as other possible issues affecting structure, such as bone density issues.

The use of a mechanism to improve breathing, such as the cpap, is of course helpful, and oxygenation improves all kinds of things in terms of preventing, possibly, further physical deterioration in some blood vessels (hence - possibly -the link to stroke and heart attack with improper oxygenation).  It gives better quality of life and more energy with better oxygenation and greater amounts of net sleep time - which in turn, helps with alertness and general well-being (and possibly pleasantness, wish my father would get one).  This does not make the ability to oxygenate at night a cure though, in my mind.

Instead, it makes it a useful tool, much like the blood thinner is in my case.  Nor, in my mind, is there any basis for thinking that the breathing disorder which is actually caused BY MS, is the actual cause OF a disorder like MS.  It is a symptom of a problem (MS) that really seems to me to be more bound up in hematological and auto-immune issues.  And in that regard, it is unfortunately all too similar to the symptomology of many other auto-immune issues, which have hematological findings that differ vastly from the norm (thus, in my mind, LEADING to the auto-immune issues, and THEN leading to the systems issues, such as the breathing issues).  And possibly with some genetic component in front of it all.  To me, this seems similar in some ways to the progression of some cancers thought to have an auto-immune basis, such as Waldenstrom's, i.e., genetics>hematology/auto-immune>systems issues.  Thus, the real area of interest to me is more in the interaction between genetics, hematology, and the auto-immune process, from a research standpoint.

And of course, with Alzheimer's, (not associating this with auto-immune disorders, but because you mentioned it as the topic header here) there is still much ongoing research, and much research yet to do.  Several things known though are that there seem to be modifications or mutations of the "Tau" protein, higher levels of the plaque peptide A-beta 42 preceeding Alzheimer's, which seem to then suddenly decrease (thought to possibly settle in the brain) as the person moves into the actual disease, and there are believed to be several genes that predispose one to Alzheimer's, such as apolipoprotein E-e4 (APOE-e4) - with others yet to be defined - possibly as many as twelve.

Now, on point with what you seem to espouse, one of the risk factors of Alzheimers and age related dementia does seem to be blood vessel damage (of course we know that a plethora of things damage the blood vessels - hypertension, high cholesterol, problems managing blood sugar, heart disease, etc) - but, certainly there does seem to be some evidence (or at least positive correlation seeming to show) that chronic lack of oxygenation from any source adds to these issues which can then influence heart disease and stroke.

So in that respect I can agree with you that chronic lack of oxygenation could certainly be a contributing factor to the progression of Alzheimers or age related dementia (and that adding oxygenation in such a situation (and in many other conditions) could only be helpful), but I can't see it as being the root cause due to all of the research that implicates, again, hematology (and genetics).  Perhaps Alzheimer's/dementia is as yet not as clearly defined as it needs to be.  This continues to be a problem for many medical disorders for which are still trying to find answers in large supply.  Perhaps it is more of a syndrome.  Maybe it can involve a host of contributing factors (as all medical problems do in one way or another on some level, I suppose).  Maybe it comes down to a genetic issue causing a hematological issue, the progression of which can be influenced by other factors such as blood vessel damage, chronic insufficient oxygenation, inactivity, etc.  But I can't see that sleep apnea, in and of itself, would cause Alzheimer's, as seemed to be postulated in the header.  I just can't get there from the evidence on hand.

At any rate, I apologize for the long post, but at the basis of my virtual blog here is, I think, the feeling that we patients sometimes have that physicians look at our medical problems one organ or body system at a time (according to their specialty) and feel they can solve issues in this manner, when so many issues are systemic in their effects - particularly when it comes to diseases of an auto-immune nature, and when the bulk of existing evidence for the etiology of the disease points to an area with specialists who don't usually even handle the disease we happen to have, and who are not well versed in it.  i.e. - perhaps someone sees a neurologist for their MS, but is MS really neurological in etiology or does the process of the disease affect the nervous system.

And I don't, honestly, have a good remedy or answer for how to manage that better that would be fair to physicians and patients alike.  Each doctor does have the responsibility to know all he can about his given specialty in order for good patient care to occur in that specialty, and no one human being can truly specialize in everything, so its a bit of a conundrum.  Anyway, thank you for your time and for entertaining what I know was a small amount of opposing opinion in some areas during my lengthy little diatribe.

alagirl,

I had to read through your post twice, as my own brain's a little foggy due to the multiple newborn baby feedings last night.

The point of all my articles is not to repeat the same old repetitive medical dogma, but to stimulate discussion and to encourage people to think outside their own medical "boxes." I'm not discounting any of the research and known facts about Alzheimers and MS. Rather, I'm describing the big elephant from a different perspective, which is from an airway/breathing perspective. One thing that I learned early on as a medical professional is that you can only state facts based on published studies, just like lawyers have to cite precedence. However, one of the problems with modern science is that you can never say that A causes B. You can only say A is strongly associated with B. Furthermore, by trying to reduce the millions of different components of a medical condition down to one single chemical or gene, it's like trying to describe a good cake as strongly associated with eggs. It's a lot more complicated than eggs. This is why you need non-study related discussions about the big picture, and constantly question conventional wisdom. Scientists and physicians often get lazy and assume that everything published recently is a scientific fact, but we all know that in 50 years, most of what we know will be turned upside-down.

Here's an exaggerated example: In medicine, you can't actually say that water cures dehydration. There are no published randomized prospective double-blinded placebo-controlled studies that prove a strong correlation between water intake and resolution of thirst and dehydration. Doctors can't officially prescribe water for dehydration. Mothers can't give water to their children for dehydration, since water is not officially FDA approved for dehydration, which is a medical diagnosis. What happens when you fall on the sidewalk? Most likely, you'll scrape your knee, but do you need to do a study to prove it? What I'm proposing here is that we're allowed to use common sense to come up with plausible connections between two seemingly unrelated medical conditions.

One point of clarification that I have with your arguments is when you talk about oxygen deprivation leading to or aggravating various medical conditions. Yes, in sleep apnea that's the extreme end of the spectrum, but what I'm talking about is breathing pauses that lead to subtle arousals that lead to deep sleep disruptions that don't usually get counted or even picked up on standard sleep studies. This leads to a physiologic stress response that sets off a cascade of hormonal, biochemical, neurologic, metabolic and immunolgic changes. Of the thousands or millions of events that occur, of course you'll find that one protein that's elevated, or that one gene that makes you susceptible to this condition. These new findings will be endless. But when was the last time the discovery of a new gene actually cured someone?

Regarding genetics, it's currently acknowledged that in many cases gene expression is markedly determined by your environment, in terms of what you eat, how you live your life, your prenatal status, and many other countless factors. With the exception of certain clearly genetic factors, many of the modern chronic conditions that we see are not determined by genetics alone.

I do agree that doctors are guilty of compartmentalizing medical conditions into their own areas or systems. I'm guilty of it too. But one thing that I've learned over the years is that to properly treat your own area of the body, you have to look at the whole person, not only in terms of physiology and anatomy, but also any stresses, family and life situation, and the entire environment that surrounds the patient. This along with the fact that doctors and the public naturally assume that all humans have this rigid tube that passes air from our noses to our lungs, but this can't be further from the truth. The human upper airway, due to a variety of factors that I describe in my book, Sleep, Interrupted, is susceptible to collapse and obstruction in everyone to various degrees. This condition has actually gotten worse over the past 100 years due to modernization.

Breathing is so fundamental to life that I think it's a safe argument to make that poor breathing can make you sick. I'm not talking about suffocation—then you'll be dead. What I describe is a chronic low-grade physiologic stress response that hypersensitizes or hyperactivates both your immune and nervous systems. The stresses of modern society only makes this physiologic stress even worse. Certain areas of the human body are also prone to lack of blood flow when under stress, namely, the hands or the feet, the bowels, the reproductive organs, the skin, or any other "end-organ" area of the body. You can imagine all the systemic inflammation and elevated markers, neurologic and hormonal changes that can occur and be measured.

You also bring up the classic chicken or the egg question. My general answer would be that a sleep-breathing problem can explain a variety of disparate medical conditions, but ultimately, it doesn't matter since it ends up being a vicious cycle. Your description of antiphospholipid syndrome sounds remarkably like the UARS condition that I describe. Every one of the symptoms and conditions that you describe can be explained via a sleep-breathing mechanism. But I think you'll agree that the elevated phopholipids alone are not causing all your medical problems. It's just a byproduct of whatever else is causing all these problems.

There's a dichotomy occurring in medicine today. There's the hardcore evidence-based medical system, which places their hopes on genetics, technology, and scientific progress. These people try to find answers within the human body down to the molecular level. Then there's the other half, who take a more holistic approach, looking at the big picture, striving for generalized balance rather than laser-focused targeting. Functional medicine is just one such example. In a very general sense, Chinese medical philosophy, for example, is much more attractive in dealing with these type of issues since they don't really have descriptions of medical conditions like we do in Western medicine. Everything is about balance of the opposing forces, and different people will need different treatment for the same condition, depending on their constitution.

To conclude, I'm not disagreeing with you at all. In fact, I actually agree with you on most of your points. Two people can describe the same elephant from two different perspectives and both can still be right. Thanks for bringing up some important issues.

Yeah, I'm afraid what we're looking at here is that I'm in that group of hardcore evidenced based medical folks that wants to find the answers down to the molecular level.  And I think that this IS the big picture.  It affects every system.  And you can treat the symptoms with cpaps (or blood thinners in my case) all day long, but you won't cure the issue until you understand and are able to change things on the micro-level.  Its at the very basis of looking at those effects on the entire body and all of the organ systems, realizing that many systems are effected, and treating ALL of the affected systems in each individual - which as you suggest, varies from person to person in certain diseases.  To me, that is the very definition of the holistic approach and it is what medicine and science are all about.

When you continue to compartmentalize a macro system and list it as a causal instead of a contributing factor in so many different illnesses, I think you have it backwards.  My biggest issue is that I don't want the blind man describing the elephant in different parts and calling each part the entire elephant.

I had a sleep doctor tell me that my chronic headaches were due to UARS and I could be cured by using a cpap.  I had another doctor tell me they were caused by constipation.  I can't agree with you about the elevated anticardiolipid antibodies not causing the medical problems I listed.  These issue are THE PRIMARY issues associated with antiphospholipid syndrome and blood thinner has caused them to discontinue.

And I did understand earlier that you think that the more subtle breathing disorders cause stress that changes blood chemistry.  I just chose not to address it because I think the role of stress is so overplayed lately by homeopaths that I don't even like to get into that argument.

Yes, all of the medical factors do work on each other in the vicious circle you described as an illness or medical issue progresses, such that the diagnostic waters are muddied.  But, that does still not negate the fact that there is an absolute etiology or etiological syndrome for the medical problem or disease in question.  And there should be a manner in which to study and quantify that or you might as well not even call it a hard science any longer.  

You have used your OWN anecdotal evidence here recently to suggest a causal link between sleep issues of different types and both MS and Alzheimer's.  And I just feel that this is not backed by the research at this time - that I can find - and I'm surprised to see it here.  That type of speculation.  We have patients here suffering from diseases who are taking your word for this when I can't find the studies to back it, and frankly, I'm sorry, but it troubles me that a physician is postulating in this manner publicly on this type of forum, with patients.  Patients on this site are GREATLY influenced by what physicians on this site say, and I feel it may be irresponsible.  As long as I'm being honest.  Particularly when your role here is to help people with sleep disorders.  If you are a homeopath or naturopath, that should be listed so that patients understand how to evaluate the data.

Dr. Park,

I have recently realized that night-time sinus congestion (I don't snore) is triggering my atrial flutter.

Due to 4 catheter ablation treatments and Sotalol, my AF is no longer persistent, but I fear it may be causing damage of some sort.

Nightly sinus congestion seems to be a recently developed symptom, and I'm not sure why it's become so prevalent.

What are the possible treatments that might eliminate these hypoxic episodes?

Thanks.

rooobosmith,

It's hard to say exactly without more information, but from what you've relayed, your nasal congestion could be aggravating an already existing sleep-breathing problem. If you have multiple obstructions at night, it can cause a stress response that activates your sympathetic nervous system, which can aggravate heart rhythm problems. You don't have to snore to have this condition.

I'm not clear if you already had a formal sleep study, since you mentioned having hypoxia. If not, then you may want to consider a formal overnight sleep study.

Simultaneously, you should get your nasal congestion taken care of definitively. If medical treatment doesn't work, then surgery may be required.

Dr. Park,

Thank you for your timely response. Frankly I am amazed.

I have not had a formal sleep study, and am only assuming hypoxia based on this and the other things which trigger my AF. They all seem to involve activities which (probably) reduce blood oxygen levels such as heavy anarobic exercise like skiing.

I will speak with my doctor tomorrow about medical treatment of my congestion.

Thanks again.

Dr. Park,

I am 19 and was diagnosed with OSA 4 years ago.  I am not over weight and never have been I am 5' 6" and weight 130 pounds.  We have found no cause for it but it is a severe case, the study showed 30-40 apneas an hour.  As a result I have been on the CPAP for the past 4 years.  Doctors are stumped as to the cause, and I have been actively pursuing the cause for 3 years (at least 12 sleep related doctors appointments per calendar year).  My cognitive abilities improved but have not fully returned.  Recently it has come to light that my grandfather, who has always been suspiciously forgetful (he has used a pocket notebook to remember things since his 20's) has Alzheimer's.  Is it possible that I, at the age of 19, have Alzheimer's?  Could Alzheimer's have caused my sleep apnea?

-Brian

Brian, thanks for posting. Your sleep apnea is because of your small jaw anatomy. Even if you're using your CPAP 100% of the time while sleeping, some people never feel completely well. There are no simple explanations for this. One can't say that you have Alzheimer's at this point, since you're very young. But if you accept my theory about one way that Alzheimer's develops, then your situation is not surprising. You should talk to your doctor to make sure that there isn't anything else (besides sleep apnea) that could be causing you to feel this way. Without doing specialized and investigational imaging tests, it's hard to "prove" any of this. Even if you see a neurologist about this, he or she probably won't even consider Alzheimer's because of your age.

Dr. Park,
I have sufffered from low grade MS like symptoms for several years without formally being diagnosed. I suspect that my snoring and insomnia over 15 years have brought on the tremors, cold muscle weakness and pins and needles sensation in my toes, feet and fingers. I have found that when I get shaky or weak that deep breathing exercises(like pearl divers do) stops these symptoms instantly! I also found that by taking 500mg L-Arginine before bed my sleep is deeper and the weakness and shaking don't occur the following day. It's after a poor nights sleep that the trouble starts.
Not a scientific study, but maybe your readers can try it and see for themselves if there is a correlation between respiration and MS/Parkinson's and blood pressure/heart disease.
I am convinced.

Jay