Can a Deviated Septum Cause Snoring?
Yes, a deviated nasal septum can cause snoring by increasing nasal airway resistance, which forces mouth breathing and creates negative intraluminal pressure in the pharynx that promotes upper airway obstruction during sleep. 1
Pathophysiological Mechanism
The connection between septal deviation and snoring operates through a clear mechanical pathway:
High nasal resistance from septal deviation increases snoring by forcing patients to breathe through the mouth, which creates more negative intraluminal pressure in the pharynx and predisposes to pharyngeal narrowing and vibration of soft tissues. 2, 1
Nasal obstruction disrupts normal upper airway physiology because nasal ventilation is associated with higher upper airway dilator muscle activity than mouth breathing, and loss of this nasal airflow stimulus can destabilize the upper airway during sleep. 2
Anterior septal deviation is particularly problematic as it affects the nasal valve area responsible for more than two-thirds of airflow resistance, making it more clinically significant than posterior deviation. 1, 3
Clinical Evidence Supporting the Connection
The evidence demonstrates a clear association, though with important nuances:
Recent research specifically shows that anterior deviation angle is significantly greater in patients with obstructive sleep apnea (mean 9.1° versus 6.5° in non-OSA patients, p=0.001), and anterior deviation was the only significant independent predictive factor for OSA presence. 3
Septoplasty demonstrates effectiveness for snoring relief in patients with nasal obstruction, with statistically significant improvements in Snore Symptom Inventory scores after surgery, irrespective of the severity of septal deviation or BMI. 4
Polysomnographic studies confirm objective improvements following septal surgery, with one study showing snoring duration decreased from 44% to 39% of sleep time, and complete relief of snoring in 19% of patients after septoplasty alone. 5
Historical case reports document dramatic clinical improvement in obstructive sleep apnea following repair of deviated nasal septum, with diminution in the number and duration of obstructive apnea episodes. 6
Critical Clinical Caveats
Not all septal deviations are clinically significant - approximately 80% of the general population has an off-center nasal septum, but only about 26% have clinically significant deviation causing symptoms. 1, 7 This means the mere presence of deviation on examination does not automatically explain snoring.
Septal deviation is a contributing factor, not necessarily the sole cause of snoring. The European Respiratory Society guidelines note that while nasal obstruction can predispose to sleep-disordered breathing, nasal surgery as a single intervention is not recommended for treatment of OSA itself, though it can improve symptoms. 2, 1
Practical Clinical Approach
When evaluating a patient with snoring and suspected septal deviation:
Document the degree of obstruction objectively - look for anterior septal deviation causing greater than 50% narrowing of the nasal aperture, as this threshold appears clinically relevant for sleep-disordered breathing. 1, 3
Assess for concurrent pathology such as inferior turbinate hypertrophy, nasal valve collapse (positive Cottle's maneuver), or allergic rhinitis, as these frequently coexist and contribute to the overall nasal resistance. 2, 1
Consider the location of deviation - anterior deviations affecting the nasal valve area are more likely to be symptomatic than posterior deviations. 1, 3
Trial medical management first with a minimum 4-week course of intranasal corticosteroids and regular saline irrigations before considering surgical intervention. 8, 7