NASAL OBSTRUCTION AS A RISK FACTOR FOR SLEEP-DISORDERED BREATHING

Nasal obstruction frequently has been associated with sleep-disordered breathing as a potential etiologic factor. Nasal obstruction results in pathologic changes in airflow velocity and resistance. Experimental ly produced nasal obstruction increases resistance and leads to sleep- disordered breathing events, including apnea, hypopnea, and snoring. C linical research examining the correlation between nasal obstruction a nd sleep-disordered breathing is limited, especially in regard to pati ents with conditions that increase nasal resistance, such as rhinitis and sinusitis. To further identify risk factors for sleep-disordered b reathing, the role of chronic and acute nasal congestion was investiga ted in a population-based sample. Data on nasal congestion history and sleep problems were obtained by questionnaire (n = 4927) and by objec tive in-laboratory measurement (n = 911). Participants who often or al most always experienced nighttime symptoms of rhinitis (5 or more nigh ts a month) were significantly (p < 0.0001) more likely to report habi tual snoring (3 to 7 nights a week), chronic excessive daytime sleepin ess, or chronic nonrestorative sleep than were those who rarely or nev er had symptoms. Habitual snorers had significantly (p < 0.02) lower a ir flow than nonsnorers, although a linear relation between decreased airflow and sleep-disordered breathing severity did not exist. Partici pants who reported nasal congestion due to allergy were 1.8 times more likely to have moderate to sever sleep-disordered breathing than were those without nasal congestion due to allergy. Men and women with nas al obstruction, especially chronic nighttime symptoms of rhinitis, are significantly more likely to be habitual snorers, and a proportion al so may have frequent episodes of apnea and hypopnea, indicative of sev ere sleep-disordered breathing. Because allergic rhinitis is a common cause of nasal obstruction and it is a modifiable risk factor, further study of this association is warranted.