Can a deviated septum cause sleep apnea?

A deviated septum can make breathing harder at night and contribute to obstructive sleep apnea. Usually, several factors are involved. Surgery may improve nasal breathing and make CPAP treatment more comfortable; whether it also reduces breathing pauses depends on the airway as a whole.

What is a deviated septum?

The anatomical change

The nasal septum is made of cartilage and bone and separates the two nasal passages. It can be off-center from birth, change during growth or shift after an injury. If it substantially narrows one side, breathing through the nose becomes harder. Symptoms can include persistent congestion, one-sided obstruction, nosebleeds and snoring.

How common is it?

Small deviations are common and often cause no noticeable problems. ENT Health cites an estimate of up to 80 percent for some degree of deviation. The source material’s figure of about 25 percent for clinically significant obstruction is not substantiated by the studies listed here and should not be treated as a general prevalence estimate. Such estimates depend heavily on what counts as a deviation and who was examined. Treatment decisions therefore depend on how much nasal breathing is actually affected.

How a deviated septum may contribute to sleep apnea

The connection with mouth breathing

When the nose is narrow, many people switch to mouth breathing. This can change the position of the lower jaw and tongue, further narrowing the throat. Muscle tone also decreases during sleep. In an already narrow or unstable upper airway, this combination can contribute to breathing pauses.

Higher airway resistance

A narrow nose requires the breathing muscles to generate more negative pressure to draw air in. That pressure also affects the softer parts of the throat. A cohort study found an association between septal deviation and sleep apnea diagnoses. The association does not establish how much the nose contributes in an individual case.

The nasal resistance theory

The Starling resistor model

Think of the airway as a relatively rigid nasal section followed by a more flexible throat. When the entrance narrows, pressure farther back falls more during inhalation. The flexible section can then collapse more easily. This model helps explain why narrowing in the nose may have effects farther down the airway.

What research adds

The septum is only one part of this system. Body weight, tongue size, jaw position, throat anatomy and muscle activity also affect risk. A systematic review helps explain why better nasal breathing does not automatically produce a similarly large improvement in sleep apnea. For some people, the nose is an important treatment target; for others, the main narrowing is in the throat.

When septum surgery may help with sleep apnea

What happens during surgery

Septoplasty straightens the nasal septum. Sometimes it is combined with reduction of enlarged turbinates. The procedure is often performed as outpatient surgery under general anesthesia. Initial recovery commonly takes one to two weeks, although swelling may take longer to settle fully.

The effect on sleep apnea

An especially useful benefit can be making CPAP treatment easier to tolerate. When air flows through the nose more freely, the mask and air pressure may feel more comfortable. A study of nasal surgery and CPAP examined that relationship.

In selected people, the number of breathing pauses may also fall. Surgery alone, however, is often insufficient for substantial sleep apnea. Snoring can become quieter even when the apnea-hypopnea index, or AHI, changes little. Subjectively calmer sleep is therefore no substitute for reassessing a diagnosed condition. Whether improved nasal breathing also helps a mandibular advancement device work better needs individual assessment.

Who might benefit most?

Significant, confirmed nasal narrowing and CPAP difficulties mainly caused by nasal breathing problems are reasons for an ear, nose and throat assessment. The nose’s contribution may differ in mild to moderate sleep apnea compared with severe disease. Symptoms, examination and sleep testing matter together, not the visible deviation alone.

Other nasal problems that can worsen sleep apnea

Enlarged turbinates

The turbinates warm and humidify inhaled air. Their lining can swell because of allergies, irritants or hormonal influences. Alongside a deviated septum, that creates another narrow point.

Nasal polyps and chronic rhinitis

Polyps or persistently inflamed nasal lining can also obstruct airflow. Treating the inflammation may improve nasal breathing even though the septum’s shape does not change.

An unstable nasal entrance

With nasal valve collapse, the front part of the nasal airway becomes too narrow during inhalation. This is a different structural problem from septal deviation and may need a different treatment.

Finding the right diagnosis

Not every nighttime breathing problem starts in the nose

An ENT examination can explain nasal obstruction. On its own, it cannot determine whether breathing repeatedly pauses during sleep. Loud snoring, witnessed breathing pauses and substantial daytime sleepiness are reasons to investigate sleep apnea too.

Why a broader assessment helps

Assessment combines an airway examination with suitable sleep testing. This records breathing disturbances and oxygen levels, among other measures. Full polysomnography can also assess sleep stages and arousals; simpler home tests do not do this in the same way. The findings help combine nasal treatment with CPAP, an oral appliance or other measures appropriately.

Frequently asked questions

Can a deviated septum cause sleep apnea in children?

It can make breathing harder. In children, enlarged adenoids or tonsils are often particularly important. Regular snoring and noticeable breathing pauses should be assessed by a pediatric clinician.

Will snoring disappear after surgery?

It may decrease if nasal obstruction is a major contributor. Other causes may remain. Less snoring therefore does not reliably mean sleep apnea has resolved.

Can you use CPAP with a deviated septum?

Yes. A well-fitted mask, adequate humidification and treatment of accompanying nasal swelling can help. A mask covering both the nose and mouth may be an option when needed. Discuss settings with your treatment team.

How do you recognize significant narrowing?

Persistent difficulty breathing through the nose, especially on one side, frequent mouth breathing or CPAP difficulties can be clues. An ENT examination, sometimes with endoscopy, can identify the cause.

Do nasal sprays help?

Anti-inflammatory sprays can reduce swollen nasal lining, for example with allergies. They do not straighten the septum. Whether surgery makes sense still depends on the overall findings and symptoms.

Is mouth taping safe with a blocked nose?

Do not tape your mouth shut at night when nasal breathing is impaired. That can further restrict the available airway. Mouth taping is not an established treatment for sleep apnea after surgery either.

Can allergies make symptoms worse?

Yes. Allergy-related swelling leaves even less room in an already narrow nose. Targeted allergy treatment can therefore make a noticeable difference.

Does a deviated septum also cause central sleep apnea?

No. In central sleep apnea, the drive to breathe temporarily stops. That is fundamentally different from the mechanical upper-airway blockage involved in obstructive sleep apnea.

Sources

• Yeom SW, Kim MG, Lee EJ, Chung SK, Kim DH, Noh SJ, Lee MH, Yang YN, Lee CM, Kim JS (2021). Association between septal deviation and OSA diagnoses: a nationwide 9-year follow-up cohort study. Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine, 17(10), 2099-2106. https://doi.org/10.5664/jcsm.9352 PubMed

• Chung F, Yegneswaran B, Liao P, Chung SA, Vairavanathan S, Islam S, Khajehdehi A, Shapiro CM (2008). STOP questionnaire: a tool to screen patients for obstructive sleep apnea. Anesthesiology, 108(5), 812-21. https://doi.org/10.1097/ALN.0b013e31816d83e4 PubMed

• Elwany S, Bahgat AY, Ibrahim M, Bazak R (2022). Surgical correction of nasal obstruction in obstructive sleep apnea improves CPAP outcomes and compliance. Irish journal of medical science, 191(6), 2723-2728. https://doi.org/10.1007/s11845-021-02896-6 PubMed

• Migueis DP, Thuler LCS, Lemes LNA, Moreira CSS, Joffily L, de Araujo-Melo MH (2016). Systematic review: The influence of nasal obstruction on sleep apnea. Brazilian journal of otorhinolaryngology, 82(2), 223-231. https://doi.org/10.1016/j.bjorl.2015.05.018 PubMed

• Ishii L, Roxbury C, Godoy A, Ishman S, Ishii M (2015). Does nasal surgery improve OSA in patients with nasal obstruction and OSA? A meta-analysis. Otolaryngology–head and neck surgery, 153(3), 326-333. https://doi.org/10.1177/0194599815594374 PubMed