What is sleep apnea?

What is Sleep Apnea?

The most obvious symptom of sleep apnea is loud snoring. It is estimated that 350,000 people in Hong Kong suffer from sleep apnea (also known as "sleep breathing pause syndrome"), yet 80% of these patients are unaware and have not received treatment.

During sleep, the patient's airway is completely blocked by the soft palate and surrounding muscle tissue, preventing air from entering or exiting. The suffocation can last for 10 seconds or even over a minute, occurring dozens to hundreds of times each night. The brain and other organs experience temporary hypoxia, causing the patient to wake up repeatedly. After normal breathing resumes, the patient falls asleep again, only to suffocate once more, in a continuous cycle. However, because the awakenings are very brief, patients usually do not notice them themselves; instead, their partners inform them of their condition

 

Sleep apnea can be divided into 3 main types:

Obstructive Sleep Apnea (OSA)

Approximately 90% of sleep apnea patients fall into this category. During sleep, the patient's upper airway narrows due to excessive throat tissue or relaxed airway muscles, leading to suffocation.

 

Central Sleep Apnea (CSA)

During sleep, the brain's "respiratory center" may fail to effectively send breathing commands due to previous neurological trauma or stroke, leading to intermittent cessation of breathing.

 

Mixed Sleep Apnea (MSA)

Simultaneously suffering from both central and obstructive sleep apnea.

 

Hypopnea

Excessive throat tissue or relaxed airway muscles cause the upper airway to narrow, but not completely block it.

 

Classification of Sleep Apnea Severity

The severity of sleep apnea is classified by the "Apnea-Hypopnea Index" (AHI - the number of apnea or hypopnea events per hour during sleep). Patients with mild to moderate conditions should consult a doctor for follow-up:

 

(AHI: <5 /hour): Normal

(AHI: 5–15/hour): Mild

(AHI: 16–30/hour): Moderate

(AHI: >30 /hour): Severe