Upper Airway Resistance Syndrome (UARS): A Complete Guide to Symptoms, Diagnosis, and Treatment

14 Aug Upper Airway Resistance Syndrome (UARS): A Complete Guide to Symptoms, Diagnosis, and Treatment

What Is Upper Airway Resistance Syndrome (UARS)?

Upper Airway Resistance Syndrome (UARS) is a sleep-disordered breathing condition in which the airway narrows during sleep, causing increased resistance to airflow—but not complete blockage. The body must work harder to breathe, triggering frequent sleep disruptions called respiratory effort-related arousals (RERAs). Unlike classic obstructive sleep apnea (OSA), UARS doesn’t always cause obvious apneas (breathing pauses) or loud snoring.

UARS is on the spectrum between primary snoring and OSA. It often goes undiagnosed because traditional sleep studies focus on the apnea-hypopnea index (AHI), which may be “normal” in UARS patients.

Prevalence & Contributing Factors:

• Most common in young adults, women, and people with slender necks or small jawbones.
• People with an airway obstruction, specifically from a nasal blockage or nasal allergies, are at higher risk.
• Family history, anatomical abnormalities (soft palate, lower jaw, tongue position), and lifestyle all contribute to increased risk.
• UARS is underdiagnosed because its symptoms are subtle and can mimic insomnia, depression, or chronic fatigue.

Differences Between Obstructive Sleep Apnea Syndrome, Snoring, and UARS:

• OSA: Complete/partial upper airway obstruction, oxygen drops, higher AHI
• Snoring: Vibration of soft tissue, often without arousals or daytime symptoms
• UARS: Airway narrows, increased respiratory effort, disrupted sleep, “normal” oxygen levels, but causes significant sleep disturbances

 

How Does UARS Affect Sleep?

With UARS, the upper airway narrows, but doesn’t completely close. Airway resistance increases, making the body work harder to breathe while sleeping. Here’s what happens:

Micro-arousals: The brain senses increased respiratory effort and wakes you up—sometimes for just a second, often without you noticing.

Disturbed sleep: These brief arousals fragment sleep cycles, leading to decreased sleep quality and chronic fatigue.

Daytime effects: Even with a “normal” number of hours in bed, UARS patients feel exhausted, foggy, or moody during the day.

Common impacts:

• Excessive daytime sleepiness
• Headaches
• Brain fog or poor focus
• Changes in mood 
• Low-quality sleep, even after sleeping long enough 

 

UARS Symptoms: How to Recognize the Signs

UARS symptoms are often “invisible” on paper but hard to miss in real life. Here’s what to look for:

Most common UARS symptoms:

• Excessive daytime sleepiness (can be mistaken for depression, ADHD, or chronic fatigue)
• Low-quality sleep
• Insomnia or trouble staying asleep
• Morning headaches
• Dry mouth or sore throat upon waking
• Cognitive issues: difficulty concentrating, memory lapses, brain fog
• Irritability or mood swings
• Frequent awakenings
• Chronic fatigue 
• Nasal congestion, allergies, or mouth breathing
• Grinding/clenching teeth (bruxism)

How does this compare to traditional sleep apnea?

OSA often features loud snoring, reduced oxygen levels, and gasping for air. The subtle, yet chronic symptoms that characterize UARS include fatigue, sleep disturbances, and daytime performance issues that can easily go under the radar. 

If this sounds familiar, book an appointment with one of our dental sleep experts today!

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Causes and Risk Factors for UARS

Why do some people develop UARS? It is a combination of anatomy, genetics, and environment.

Leading Causes and Risk Factors:

Narrow or collapsible upper airway

• Small jaws (retrognathia)
• Large soft palate or tongue
• The throat relaxes too much during sleep

Nasal obstruction or allergies

• Deviated septum
• Chronic congestion
• Nasal polyps
• Untreated allergic rhinitis 

Family history

Genetics play a role in airway structure, which is affected by the jaw, nose, and throat. Inheriting certain facial features can make some more susceptible to developing UARS.

Lifestyle factors

• Alcohol or sedative use can relax throat muscles
• Smoking causes inflammation and/or congestion
• Gravity narrows the airway when sleeping on your back

Soft tissue crowding: Enlarged tonsils and/or adenoids are common UARS risk factors for children.

Other conditions: Connective tissue disorders (e.g., Ehlers-Danlos syndrome)

 

Potential Causes of UARS

Risk Factor	Impact on the Airway
Small lower jaw	Narrows airway
Nasal obstruction/allergies	Increases mouth breathing
Soft tissue crowding	Increases airway resistance
Obesity	Narrows and obstructs the airway; soft tissue crowding
Sedatives/alcohol	Throat relaxes, collapses

 

How Is UARS Diagnosed?

Upper airway resistance syndrome can be challenging to diagnose because sleep studies do not always detect apneas or significant drops in oxygen levels. Most standard sleep studies focus on classic apneas and obstructive hypopneas.

Key Diagnostic Tools:

1. Polysomnography (PSG) / Sleep study:
   • Measures brain waves, airflow, oxygen, and respiration effort
   • Despite a normal AHI, UARS shows increased effort and frequent arousals, detectable with esophageal pressure monitoring or nasal pressure monitoring.
   • Respiratory effort-related arousals (RERAs) are the leading indicator of UARS; however, these don’t count toward the AHI score in standard sleep studies.
2. Apnea Hypopnea Index (AHI):
   • UARS patients often have AHI <5/hr (below the OSA threshold), yet have significant symptoms
3. Clinical evaluation:
   • Detailed history of symptoms, examination of the upper airway, and sometimes imaging is required (CT, MRI).
   • Structural issues like nasal obstruction or a small jaw can be a physical clue.

Challenges:

• Many labs don’t routinely measure RERAs
• Patients often receive results saying their sleep study is “normal.”
• Misdiagnosis as “just insomnia,” “anxiety,” or “chronic fatigue”

Finding relief begins with seeking the right sleep center with experience in diagnosing and treating UARS. TMJ & Sleep Solutions of Alabama offers individualized solutions for every type of patient. 

 

UARS Treatment Options

Treating UARS means keeping the airway open and reducing resistance so the brain stops waking you up all night. Here’s what works:

Continuous Positive Airway Pressure (CPAP):

A CPAP machine is one of the most commonly used treatments. It uses air pressure to force the patient’s upper airway open while sleeping. Although it’s the gold standard, many patients are CPAP-intolerant or find it hard to tolerate due to its bulkiness, loudness, and hassle. For patients with less severe symptoms, there are better options to recommend. 

Oral Appliance Therapy (mandibular advancement devices):

Oral appliance therapy is a promising option for less-symptomatic patients or those who are CPAP-intolerant. OAT involves a small, noninvasive, custom-fit device that patients wear in their mouth while sleeping. By design, it keeps the lower jaw forward, expands the upper airway, and keeps the tongue out of the way.

Traits that characterize CPAP-intolerance for patients include claustrophobia, difficulty adapting to air pressure from a CPAP device, excessive chapped lips, and more. 

If you’re interested in an OAT device, learn more about the cost here.

Lifestyle Changes:

Lifestyle changes can significantly impact sleep disorders and are encouraged alongside treatment. Losing weight and trying positional sleep therapy and sleep breathing exercises can help support sleep disorders. 

Some things to consider:

• Avoid sedatives and/or alcohol before sleep
• Losing excess weight can reduce soft tissue crowding
• Improve sleep hygiene

Surgical Treatment:

Surgical procedures are an option for more severe cases. Anatomical abnormalities that are resistant to noninvasive forms of treatment can be addressed with jaw surgery, nasal surgery, uvulopalatopharyngoplasty (UPPP), etc. 

Our blog is a valuable resource for detailed information on treatment plans.

 

UARS Treatment Options

Treatment Type	Pros	Cons / Notes
Lifestyle Changes	No side effects	May not resolve issues alone
Oral Appliances	Comfortable, easy to use	Not for all anatomies
Positional Therapy	Noninvasive, affordable	Less effective for severe cases
CPAP	Gold standard, effective	Low adherence rate; causes discomfort for some
Surgery	Can address the root cause	Increase in risk, recovery time

 

Living With UARS: Tips and Resources

If you’ve been diagnosed with UARS—or you suspect you have it—managing your sleep is possible with our everyday tips:

• Use a nasal saline rinse or treat allergies to reduce congestion.
• Try positional therapy, training yourself to sleep on your side.
• Stick to a consistent sleep schedule.
• Avoid heavy meals, alcohol, and sedatives before bed.
• Practice good sleep hygiene with a cool, dark, quiet, and comfortable bedroom.
• Ask your provider about oral appliances if CPAP doesn’t work for you.

Explore our in-depth guide to better rest. 

When to see a sleep science specialist:

• Your symptoms persist despite making changes in your routine
• You feel exhausted despite getting “normal” results from sleep studies
• Your symptoms become chronic
• You want a second opinion from a sleep physician

 

Frequently Asked Questions About UARS

What is upper airway resistance syndrome (UARS)?

UARS is a sleep disorder where the upper airway narrows, causing increased resistance to airflow and repeated sleep disruptions, but not complete breathing pauses as seen in patients with sleep apnea.

How is UARS different from obstructive sleep apnea (OSA)?

Unlike OSA, UARS rarely causes significant drops in oxygen or long breathing pauses. It’s characterized by increased breathing efforts and frequent sleep arousals, even with a normal apnea-hypopnea index.

What are the main symptoms of UARS?

Chronic fatigue, non-refreshing sleep, insomnia, headaches, dry mouth, and “brain fog” are common symptoms in UARS patients; loud snoring and choking are less typical for them, but are more prevalent among patients with OSA.

How is UARS diagnosed?

Diagnosis typically requires a sleep study, careful measurement of respiratory effort-related arousals (RERAs), and a thorough clinical evaluation.

What are the treatment options for UARS?

CPAP, oral appliances, positional therapy, treating nasal obstruction, lifestyle changes, and sometimes surgery. Many patients do well with oral devices if they are CPAP-intolerant.

Can UARS cause sleep apnea?

Yes, untreated UARS can progress to OSA over time, especially with age or weight gain.

Is UARS serious if left untreated?

Yes. Untreated UARS can lead to chronic fatigue, mood issues, increased accident risk, and may evolve into more serious sleep disorders.

 

Contact Us Today!

At TMJ & Sleep Solutions of Alabama, we provide custom care tailored to your individual needs. Whether you come to us with a referral or to seek a diagnosis, we’re here to help you find the right solution. It’s time for a good night’s sleep; schedule your consultation with us today!

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