What is sleep apnea
Last updated: April 1, 2026
Key Facts
- Obstructive sleep apnea (OSA) is the most common type, caused by airway blockage, while central sleep apnea involves the brain failing to signal breathing muscles
- Untreated sleep apnea increases risk of heart attack, stroke, high blood pressure, and sudden cardiac death by 2-3 times
- Men are 2-3 times more likely to develop sleep apnea than women, with risk increasing significantly after age 65
- Common symptoms include loud snoring, gasping for air during sleep, daytime sleepiness, morning headaches, and difficulty concentrating
- Sleep apnea affects an estimated 30 million Americans, with approximately 80% of moderate to severe cases undiagnosed
Overview
Sleep apnea is a serious sleep disorder characterized by repeated breathing interruptions during sleep. Each interruption, called an apnea, lasts at least 10 seconds and can occur dozens to hundreds of times per night. These interruptions reduce oxygen levels in the blood and disrupt sleep quality, leading to daytime fatigue and serious health complications if left untreated.
Types of Sleep Apnea
Obstructive Sleep Apnea (OSA) is the most common form, accounting for 84% of cases. It occurs when throat muscles relax and block the airway during sleep. Central Sleep Apnea is less common and occurs when the brain fails to send proper signals to breathing muscles. Complex Sleep Apnea is a combination of both types.
Symptoms and Warning Signs
Common symptoms include:
- Loud snoring or gasping sounds during sleep
- Witnessed breathing pauses by a sleep partner
- Excessive daytime sleepiness and fatigue
- Morning headaches and dry mouth upon waking
- Difficulty concentrating, memory problems, and mood changes
- Restless sleep and frequent nighttime awakenings
- In children: hyperactivity, learning problems, and failure to thrive
Risk Factors and Causes
Risk factors for obstructive sleep apnea include obesity, male gender, age over 50, and family history. Other contributing factors include neck circumference greater than 17 inches in men or 16 inches in women, smoking, alcohol use, nasal congestion, and certain anatomical features like enlarged tonsils or a recessed chin. Central sleep apnea is often associated with heart disease, stroke, neurological conditions, or opioid medication use.
Health Consequences
Untreated sleep apnea has serious cardiovascular and metabolic consequences. The repeated oxygen drops and sleep fragmentation increase blood pressure and strain on the heart, significantly increasing risk of heart attack, stroke, atrial fibrillation, and sudden cardiac death. Sleep apnea also contributes to weight gain, insulin resistance, and type 2 diabetes development.
Diagnosis and Treatment
Sleep apnea is diagnosed through a sleep study (polysomnography) conducted in a lab or at home. The study measures breathing patterns, oxygen levels, heart rate, and sleep stages. Treatment options include continuous positive airway pressure (CPAP) devices that keep airways open, oral appliances that reposition the jaw, positional therapy, weight loss, and in some cases, surgery. Lifestyle modifications like avoiding alcohol and sleeping on the side also help manage symptoms.
Related Questions
What does a CPAP machine do?
A CPAP machine delivers pressurized air through a mask to keep the airway open during sleep, preventing breathing interruptions. It is the most common and effective treatment for obstructive sleep apnea, improving sleep quality and reducing health risks.
How is sleep apnea diagnosed?
Sleep apnea is diagnosed through a sleep study called polysomnography, which monitors breathing, oxygen levels, heart rate, and brain activity during sleep. Home sleep tests are also available for people with suspected obstructive sleep apnea.
Can sleep apnea be cured?
While there is no cure for sleep apnea, it can be effectively managed with CPAP machines, oral appliances, positional therapy, weight loss, and in some cases, surgery. Treatment eliminates symptoms and reduces associated health risks.
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Sources
- National Heart, Lung, and Blood Institute - Sleep ApneaPublic Domain
- Wikipedia - Sleep ApneaCC-BY-SA-4.0
- Mayo Clinic - Sleep ApneaFair Use