Upper Airway Resistance Syndrome (UARS) is one of those clinical terms that rarely gets the spotlight, yet it affects countless people struggling to feel rested. Part of the broader family of sleep-disordered breathing (SDB) conditions, UARS often sits in the shadow of its more well-known cousin, Obstructive Sleep Apnea (OSA).
But here’s the catch: it’s not the same thing.
While OSA is marked by complete or partial airway obstructions that cause oxygen desaturation and loud snoring, and Central Sleep Apnea (CSA) stems from disrupted brain signals controlling breathing, UARS is more subtle. It involves increased resistance in the upper airway that doesn’t necessarily cause oxygen levels to drop but still disrupts sleep through frequent arousals—what sleep doctors call Respiratory Effort-Related Arousals (RERAs). In short, your brain keeps waking you up just enough to break the sleep cycle, over and over again.
Despite its milder appearance on paper, UARS can wreak havoc on a person’s quality of life—and because it’s trickier to diagnose, many patients go undiagnosed for years.
Etiology and Pathophysiology
To understand UARS, we need to zoom in on what’s happening during sleep—specifically in the upper airway. Unlike OSA, which involves full or partial airway collapse, UARS is all about resistance. Think of breathing through a narrow straw: air still gets through, but it takes more effort. That’s essentially what’s going on in UARS. The airway doesn’t completely close, but it narrows just enough to make inhalation harder, especially during deeper stages of sleep.
This resistance leads to something called increased inspiratory effort, where the body has to work harder to draw air in. Over time, this effort builds up pressure in the chest until the brain is forced to intervene by triggering a brief arousal. These aren’t full awakenings that you’d necessarily remember—just enough of a jolt to disrupt the normal progression through the sleep stages. And when this happens repeatedly throughout the night, it creates sleep fragmentation and poor sleep architecture.
So what causes this airway resistance in the first place? It’s often a mix of anatomical and neuromuscular factors. People with a narrow jaw, low-hanging soft palate, or enlarged turbinates are more prone to restricted airflow. Neuromuscular tone in the throat also plays a role—if the muscles that keep the airway open relax too much during sleep, even a structurally “normal” airway can become problematic.
In other words, UARS sits at the intersection of structure and function—it’s not just about what your airway looks like, but how it behaves when you’re asleep.
Epidemiology
Upper Airway Resistance Syndrome doesn’t grab headlines the way OSA does, but that doesn’t mean it’s rare. What makes UARS tricky is that it often flies under the radar—misdiagnosed, underdiagnosed, or dismissed entirely because standard sleep tests focus on oxygen desaturation rather than the subtle disruptions that define UARS.
Estimates vary, but some studies suggest that up to 15% of patients who undergo sleep studies for fatigue and non-restorative sleep may actually have UARS—not OSA. What’s more, the demographic profile of UARS differs from what many expect. Unlike OSA, which is more common in overweight, middle-aged men, UARS tends to affect younger adults and has a higher prevalence among women, particularly those with normal body weight.
This is crucial: UARS often shows up in patients who don’t “look” like typical sleep apnea sufferers. That means a 30-year-old woman with chronic fatigue, headaches, and no history of snoring could still be battling UARS every night. It’s a pattern that has led to countless missed diagnoses, especially among patients whose sleep studies come back “normal” by traditional scoring standards.
Other potential risk factors include craniofacial features like a narrow jaw or high-arched palate, nasal congestion, and a history of orthodontic work or mouth breathing. UARS also appears more frequently in people with anxiety, fibromyalgia, and other conditions linked to autonomic dysregulation—suggesting a deeper, systemic connection worth further exploration.
Symptoms and Clinical Presentation
If you’ve ever woken up exhausted after what seemed like a full night’s sleep, you might understand the frustration that comes with UARS. The symptoms aren’t dramatic, but they’re persistent, disruptive, and often dismissed—by both patients and providers.
The most common complaints include chronic fatigue, daytime sleepiness, unrefreshing sleep, frequent nighttime awakenings, and morning headaches. While snoring may occur, it’s typically softer or intermittent compared to the loud, gasping snore patterns of OSA. In fact, many people with UARS don’t snore at all, which makes the condition even easier to overlook.
You might also see symptoms that extend beyond sleep: brain fog, difficulty concentrating, mood disturbances like irritability or depression, and even heightened anxiety. And these aren’t just minor annoyances—they can have a real impact on daily functioning, relationships, and work performance. For some patients, these effects feel like living in a constant state of exhaustion, no matter how early they go to bed.
There’s also growing evidence linking UARS to autonomic nervous system imbalance, particularly heightened sympathetic tone (the body’s fight-or-flight response). This might explain why many people with UARS describe feeling “wired but tired”—mentally edgy while physically drained.
In kids and adolescents, the presentation may differ. UARS might masquerade as attention issues, behavioral problems, or academic struggles, sometimes leading to misdiagnoses like ADHD when sleep is actually the underlying problem.
The bottom line? UARS presents subtly, often escaping detection. But its cumulative effect on quality of life, mental clarity, and emotional regulation is undeniable.
Diagnostic Evaluation
Diagnosing UARS is where things get challenging—but also where awareness can truly change lives. Because UARS doesn’t typically cause oxygen desaturation, standard screening tools and home sleep apnea tests often miss it entirely. That’s why patients with textbook symptoms can be told their results are “normal,” even though they feel anything but.
The gold standard for diagnosing UARS is polysomnography (PSG)—a comprehensive, in-lab sleep study that measures everything from brain waves to respiratory effort. What sets UARS apart is the presence of Respiratory Effort-Related Arousals (RERAs). These are subtle breathing disturbances where increasing effort is required to pull air through the upper airway, ultimately triggering a brief arousal before full obstruction ever occurs.
Unfortunately, many labs don’t routinely score RERAs unless specifically asked. That’s why it’s crucial to work with a sleep specialist who understands the nuances of sleep-disordered breathing and isn’t just looking for apneas and hypopneas. In some cases, adding an esophageal pressure (Pes) sensor to the sleep study may be necessary to confirm increased inspiratory effort—a hallmark of UARS.
The Apnea-Hypopnea Index (AHI)—used to grade OSA severity—is usually under 5 in UARS patients, meaning they fall into a gray area: symptomatic, but technically “normal.” This diagnostic gray zone has contributed to under-recognition of UARS for many years, and why it requires a clinical diagnosis that blends objective data with a deep understanding of subjective symptoms.
Distinguishing UARS from OSA is important not only for diagnosis but for treatment planning. Though the two share some overlap, the treatment response and patient goals may differ—and mislabeling a UARS patient as “fine” can leave them struggling for years without relief.
Management and Treatment Options
Treating Upper Airway Resistance Syndrome (UARS) is both an art and a science. The goal isn’t just to reduce arousals—it’s to restore deep, uninterrupted sleep, rebuild daytime energy, and protect long-term health. Because UARS exists in that in-between zone—not quite OSA, not quite normal—it requires a personalized, symptom-focused approach.
Let’s start with the most established therapy:
Continuous Positive Airway Pressure (CPAP). While CPAP is most famously used for OSA, it can also be incredibly effective for UARS. The machine provides a gentle, continuous stream of air that keeps the upper airway open—preventing flow limitation and reducing respiratory effort. But here’s the catch: many UARS patients are sensitive to discomfort, and some may find standard CPAP settings too forceful. For these patients, auto-titrating machines, pressure ramp features, or bilevel devices may improve tolerance.
For those who can’t tolerate CPAP—or who present with mild anatomical issues—oral appliance therapy is another strong option. These devices reposition the lower jaw and tongue during sleep, helping to enlarge the airway and minimize resistance. While they may not be as aggressive as CPAP in eliminating arousals, many patients find them more comfortable and sustainable long-term.
Then there are surgical interventions, which may be considered in more complex or refractory cases. Procedures like nasal turbinate reduction, septoplasty, tonsillectomy, or even maxillomandibular advancement (MMA) can help address underlying structural causes of airflow resistance. That said, surgery is typically reserved for those who don’t respond to conservative treatments.
Some clinicians are exploring pharmacological options as well. Medications that reduce nasal congestion (like topical steroids or antihistamines), or agents that increase airway muscle tone, are being studied—but evidence is still evolving.
No matter the approach, success hinges on individualized care. What works for one person may not work for another. That’s why ongoing follow-ups, symptom tracking, and sometimes repeat sleep studies are essential to fine-tune treatment and ensure real-world benefits.
Complications and Prognosis
Don’t let the word “mild” fool you—Upper Airway Resistance Syndrome, when left untreated, can lead to serious consequences. While UARS may not carry the same immediate oxygen desaturation risks as Obstructive Sleep Apnea (OSA), the repeated sleep fragmentation and sympathetic nervous system activation still take a significant toll on the body over time.
One of the most concerning risks is its potential role in the development of cardiovascular issues. Multiple studies have linked sleep-disordered breathing, even in its milder forms, to elevated blood pressure, heart rate variability, and endothelial dysfunction—all early markers of cardiovascular disease. In patients with untreated UARS, chronic arousals can lead to persistent sympathetic overdrive (think: your body’s fight-or-flight mode stuck in the “on” position), which may elevate the risk for hypertension, arrhythmias, and possibly even metabolic syndrome.
There’s also the risk of progression to OSA. While not every UARS patient will go on to develop full-blown apnea, the combination of aging, weight gain, and muscle tone changes can gradually tip the balance toward more severe obstruction over time. Early recognition and intervention can potentially slow or even prevent that trajectory.
Beyond the physiological risks, UARS can seriously impact mental health and quality of life. Chronic fatigue, emotional volatility, and cognitive fog can strain relationships, derail careers, and chip away at self-esteem. In children and teens, UARS has been linked to academic difficulties, hyperactivity, and developmental delays—reminding us that early diagnosis is just as crucial for younger patients.
That said, the prognosis for treated UARS is generally excellent. With the right diagnosis and personalized management, most patients experience dramatic improvements in energy, mood, focus, and overall wellness. The key is catching it early—and taking it seriously.
Patient Education and Counseling
When it comes to UARS, patient understanding can make or break the treatment journey. Because the condition is subtle and often misunderstood—even among healthcare professionals—many patients go through years of misdiagnoses, ineffective treatments, or simply being told “everything looks normal.” That’s why clear, compassionate education is absolutely essential.
Start by helping patients understand that UARS is real, valid, and treatable. Just because their sleep study didn’t flag any apneas or oxygen drops doesn’t mean their symptoms are “in their head.” Explain the concept of respiratory effort-related arousals (RERAs) and how these interruptions—though brief—can wreck the restorative power of sleep. For many people, this is the first time someone has connected the dots between their daily exhaustion and the way their body is working overtime just to breathe at night.
It’s also helpful to set realistic expectations. Treatment isn’t one-size-fits-all, and it might take some trial and error to find what works best—whether that’s CPAP, oral appliances, or lifestyle modifications. Encourage patients to be active participants in their care: track their sleep, notice how different treatments affect daytime energy, and communicate openly with their sleep team.
Lifestyle education is important, too. Patients should know that habits like nasal breathing, avoiding alcohol or sedatives before bed, and addressing allergies or nasal congestion can all support treatment success. In some cases, referring to an orofacial myofunctional therapist or ENT specialist may be part of the long-term strategy.
Finally, provide resources. Point them toward credible organizations like the American Academy of Sleep Medicine or educational materials tailored to sleep-disordered breathing. Online support groups and forums can also be helpful, giving patients a place to connect, ask questions, and realize they’re not alone.
When patients feel informed and empowered, they’re far more likely to stick with treatment and reclaim their sleep—and their life.
Upper Airway Resistance Syndrome (UARS) may not carry the dramatic warnings of obstructive or central sleep apnea, but its impact is no less real. This condition disrupts sleep in quiet but deeply consequential ways—robbing people of energy, focus, emotional balance, and long-term health. Because it doesn’t fit neatly into the more recognized apnea categories, many patients are left undiagnosed or misunderstood, sometimes for years.
But there’s good news: with the right approach, UARS is treatable. Through detailed evaluation, including comprehensive polysomnography that scores for respiratory effort-related arousals (RERAs), clinicians can uncover the subtle mechanics behind a patient’s exhaustion. And with tailored treatment—whether that’s CPAP, oral appliances, nasal therapies, or even surgery—people often report life-changing improvements in how they sleep and how they feel during the day.
More importantly, managing UARS is never just about machines or measurements. It’s about restoring control, confidence, and well-being for people who’ve been told too many times that their symptoms don’t make sense. That takes a collaborative, interprofessional approach—sleep physicians, dentists, ENTs, mental health professionals, and most of all, informed patients working together.
Because at its core, treating UARS isn’t just about clearing the airway. It’s about making room for deeper sleep, better mornings, and a life that finally feels sustainable again.