Both snoring and obstructive sleep apnoea (OSA) have a common origin: the obstruction of the upper airway caused by the relaxation of muscles controlling the soft palate and tongue. In snorers without OSA, the airway is obstructed, but not collapsed, though there are flow limitations. In snorers with OSA, there is a partial or complete collapse of the airway, leading to either
An apnoea, which is the cessation of airflow for 10 seconds or more.
A hypopnoea, which is a decrease in airflow lasting for more than 10 seconds, with a reduction of 30% in airflow and at least 4% oxygen desaturation from baseline.
Causes of snoring
Several factors can increase snoring intensity: fatigue, excess weight, sleeping on the back, and drinking alcohol before going to bed are all conducive to loud snoring. People with enlarged tonsils, an enlarged tongue or excess weight around the neck are also prone to snoring. Even structural reasons like the shape of one’s nose or jaw can cause snoring.
Snoring and OSA
Snoring is considered as the primary symptom for obstructive sleep apnoea.1 Long considered nothing more than a social nuisance, it’s now seen as the initial step of a continuum that can lead to more severe forms of OSA.2
Ask your patients if they suffer from loud snoring as well as excessive daytime somnolence. If they do, you should recommend a sleep test in order to gauge their AHI levels so you can prescribe them appropriate treatment.
Meslier N, Racineux JL. Snoring and high-resistance syndrome. Rev Mal Respir 2004; 21 : 2S35-2S42. (French)
McNamara SG, Cistulli PA, Sullivan CE, Strohl KP. Clinical aspects of sleep apnea. In: Saunders NA, Sullivan CE, editors. Sleep and breathing: lung biology in health and disease. 2nd ed. New York: Marcel Dekker; 1994: 337-61.