Possible Link Between Obstructive Sleep Apnea and the Sense of Smell
An overlooked symptom in people with obstructive sleep apnea (OSA) is olfactory dysfunction (i.e., impairment in the sense of smell) such as an inability to detect or distinguish between odors. A finding that the sense of smell improves soon after a person with OSA begins continuous positive airway pressure (CPAP) treatment corroborates a possible link between olfactory dysfunction and OSA.
OSA is the intermittent cessation of breathing during sleep. It occurs because the upper airway muscles relax excessively during sleep, which allows structures supported by the muscles to collapse into and obstruct the upper airway. This blockage restricts airflow and consequently decreases the blood oxygen level. A person makes increasingly strong efforts to breathe.
Despite this effort, the blockage remains. When the blood oxygen level falls to a certain point, the respiratory center in the brain triggers a brief arousal (lasting for a few seconds) during which the upper airway muscle tone is restored. The person can then take some deep, quick breaths that restore the blood oxygen level.
The most common treatment for OSA is continuous positive airway pressure (CPAP). In this treatment, a continuous flow of pressurized air is delivered through a mask that fits over the nose or nose and mouth. The force of the air prevents the upper airway structures from collapsing into the airway as a person relaxes during sleep, thereby effectively preventing OSA episodes.
Another treatment for OSA is a surgery called uvulopalatopharyngoplasty (UPPP), which opens the upper airway by removing tissues (e.g., uvula, enlarged tonsils and adenoids) and reshaping the soft palate. With these tissues unable to collapse into and block the upper airway during sleep, OSA episodes can be reduced. An adverse effect of UPPP reported by some people is the loss of or a diminishment in the sense of smell.
In the rest of this article from the Q1 2019 issue of A2Zzz, Regina Patrick goes into how OSA contributes to an impaired sense of smell.
This article is one of four designated CEC articles in this issue of A2Zzz. AAST members who read A2Zzz and claim their credits online by the deadline can earn 2.00 AAST Continuing Education Credits (CECs) per issue – for up to 8.00 AAST CECs per year. AAST CECs are accepted by the Board of Registered Polysomnographic Technologists (BRPT) and the American Board of Sleep Medicine (ABSM).
To earn AAST CECs, carefully read the four designated CEC articles and claim your credits online. You must go online to claim your credits by the deadline of May 20, 2019.
After the successful completion of this educational activity, your certificates will be available in the My CEC Portal acknowledging the credits earned.