Patient Education

Sleep apnea is a common condition where your breathing repeatedly stops and starts during sleep. The most common type, obstructive sleep apnea (OSA), happens when the muscles in the back of your throat relax too much during sleep, temporarily blocking your airway. [1]

What happens during an apnea event?

When the airway narrows or closes, your body briefly wakes itself up to resume breathing. These micro-awakenings — often too short for you to remember — can happen dozens or even hundreds of times per night. The result: fragmented sleep that leaves you feeling exhausted, even after what seems like a full night of rest. [1]

Understanding the AHI

The Apnea-Hypopnea Index (AHI) is the number used to measure sleep apnea severity. It counts how many times your breathing slows or stops per hour of sleep.

Types of sleep apnea

• Obstructive (OSA): The most common form. Your throat muscles relax and physically block the airway.
• Central (CSA): Less common. Your brain temporarily stops sending signals to the muscles that control breathing.
• Complex/Mixed: A combination of both obstructive and central events.

Common signs and symptoms

• Loud or chronic snoring
• Gasping or choking during sleep (often reported by a partner)
• Waking up with a dry mouth or headache
• Excessive daytime sleepiness
• Difficulty concentrating or mood changes
• Waking frequently to use the bathroom at night