Gaps in Sleep Medical Knowledge: Part IV (The Unsolved Puzzle of UARS)

In a number of prior posts I addressed issues involving UARS. In series on cascade preferences, we discussed how natural it has been to suppress knowledge about UARS. In part two, we talked about how gaps in the general scientific literature may lead doctors away from consideration of the UARS condition and how these gaps are readily apparent in the field of sleep medicine itself. In part three, we delved into a discussion on how insurers operate as well as how physicians may interact with these carriers to the detriment of our patients. After posting this three-part series, we received comments from individuals who were going through the process of trying to diagnose or treat their UARS. And, we pointed to the fact that many patients are similarly affected by this lack of attention to UARS. In addition to these posts, we also discussed the technical side of UARS regarding how to distinguish it from leg jerks and early comments on sleep professionals who do not score these breathing events.

Now we want to delve into how a gap in knowledge has led to fewer resources available to treat patients who suffer from this diagnosable and treatable condition. 

The best way to think about UARS is to ask the question, “if losing all your breathing (apnea) feels like suffocating and losing 50% of your (hypopnea) feels like choking, does losing 25% of your breathing (a UARS event: RERA or FLE) somehow feel like a walk in the park?” Try wrapping your hands around your throat and cutting off all the air to your windpipe, then try cutting off just 50% of your airflow, and finally just let 75% of the air come through as you cut off only the other 25%. I am kidding of course! Don’t try this at home or anywhere else, but for a second imagine what it would feel like if you suddenly experienced a loss of 25% of what you normally breathe in. The answer is obvious: you would find it extremely uncomfortable, and some people would be sensitive enough to panic from the episode. 

It is therefore unfathomable that anyone would choose to argue that UARS is a controversial or ill-defined metric. Yet, many leaders in the field of sleep medicine have consistently dismissed the UARS concept; and, astonishingly in the upper echelons of the field there are those who declare they have never seen a RERA and never diagnosed a case of UARS. This perspective is quite bizarre, because the scientific evidence demonstrates the combination of decreased breathing volume not meeting the 30% lower limit of hypopnea and the obvious absence of a normal airflow signal is incontestably an abnormal breathing event, regardless of the term used to designate it. Add in the fact such breathing events almost invariably are linked to an arousal, and now we have a conceptual model equivalent to an apnea or hypopnea: an abnormal airflow signal coupled with a sign of sleep fragmentation (the EEG arousal) in a patient seeking treatment at a sleep disorders center and who with great probability is likely presenting with a chief complaint of daytime fatigue or sleepiness or insomnia or all three problems.

Given research clearly demonstrating many of these patients will achieve improvement in any or all three of these symptom clusters, it is unconscionable to maintain a posture that UARS is not a diagnosable and treatable condition. Yet, the American Academy of Sleep Medicine, presumably bowing to pressures once again from insurance carriers sought to rewrite UARS out of its dictionary of diagnosable sleep disorders by declaring this sleep breathing condition is just another form of OSA, and therefore the term UARS can be discarded. Thus, UARS patients can now be called OSA patients, which in fact are what many sleep specialists are starting to do.

On the one hand, we might consider this terminological sleight of hand a plus, because now the AASM is recognizing that UARS is a legitimate sleep breathing disorder but with a different name. On the other hand, the problem arises or remains (depending upon how you read UARS history) of misleading sleep doctors and technologists in how they are supposed to properly score the breathing events of UARS.

We have already addressed this problem in two commentaries to the Journal of Clinical Sleep Medicine describing how current sleep medicine standards do not even require the scoring of RERAs by any sleep facility on a diagnostic study. The actual declaration indicates scoring of RERAs for diagnostic purposes to be “optional.” So, if the AASM has reconfigured the scoring of hypopneas (Knowledge Gap: Part III) to make them closer but not identical to RERAs (changing hypopnea drop in airflow from 50 to 30%), and if RERAs do not need to be scored, how are sleep professionals supposed to diagnose a condition whose name—UARS—no longer exists but apparently does exist if you call it OSA?

I trust your confusion is as great as mine, but this confusion is no joking matter. We continue to see second opinion patients at our sleep center where the previous center never scored the diagnostic study for UARS breathing events (RERAs, FLEs), and the patients were sent home without any diagnosis and told to seek care elsewhere, because they were not suffering from a sleep disorder. This problem undoubtedly occurs all over the USA, given what appears to be the preponderance of sleep professionals who ignore UARS altogether, and can you blame them when they are asked to read and digest such flawed and non-scientific directives regarding the evaluation and treatment of these patients?

All that would have been required from the leadership in the field of clinical or research sleep medicine was a concerted effort to flood insurance carriers and Medicare with publication after publication demonstrating the nature and consequences of untreated UARS. Had the American Academy of Sleep Medicine, as prime example, also simply have asked its members to send hundreds of case histories to these non-sleep institutions along with a barrage of the evidence published in the 1990s, there are reasons to believe this gap in knowledge would have been filled in such a way to more directly influence those who otherwise were looking at sleep medicine as an easy target through which to cut costs.

The most unfortunate aspects of the whole affair were the clinical and research leaders who then and even now still deny the existence of these subtle sleep breathing disturbances for no apparent reason. The condition of UARS, by whatever name, fragments sleep and causes or aggravates problems with insomnia and daytime fatigue and sleepiness. Those who reject these proven concepts often appear in league with those who reject the value of treatment for mild OSA, where the apnea-hypopnea index typically measures out between 5 to 15 events per hour. And, yet many of these patients are not really mild when their sleep studies are properly scored to account for the UARS components (RERAs, FLEs) of the breathing disorder.

This gap in the field remains huge and shows no signs of being filled anytime soon.


Read more from this series:

Gaps in Sleep Medical Knowledge: Part I (Normal Sleep)
Gaps in Sleep Medical Knowledge: Part II (Normal Breathing)
Gaps in Sleep Medical Knowledge: Part III (The Medicare Hypopnea Scoring Maze)
Gaps in Sleep Medical Knowledge: Part IV (The Unsolved Puzzle of UARS)
Gaps in Sleep Medical Knowledge: Part V (Coding Issues for Billing and Reimbursement)
Gaps in Sleep Medical Knowledge: Part VI (Prior Authorizations and Atypical Patients)
Gaps in Sleep Medical Knowledge: Part VII (Confusing Compliance with Outcomes)
Gaps in Sleep Medical Knowledge: Part VIII (Comorbid Sleep Disorders)
Gaps in Sleep Medical Knowledge: Part IX (Miscellaneous Topics)


Barry Krakow MD


Dr Krakow’s 27 years of sleep research have focused on the complex relationship between physiological and psychological sleep disorders. Dr Krakow currently operates private sleep medical center, Maimonides Sleep Arts & Sciences, Ltd., and serves as Classic SleepCare’s paid Medical Director.

Leave a comment

Comments have to be approved before showing up.