When you're awake, throat muscles help keep your airway stiff and open so air can flow into your lungs. When you sleep, these muscles relax, which narrows your throat.
Normally, this narrowing doesn’t prevent air from flowing into and out of your lungs. But if you have sleep apnea, your airway can become partially or fully blocked because:
Not enough air flows into your lungs if your airway is partially or fully blocked during sleep. As a result, loud snoring and a drop in your blood oxygen level can occur.
If the oxygen drops to a dangerous level, it triggers your brain to disturb your sleep. This helps tighten the upper airway muscles and open your windpipe. Normal breathing then starts again, often with a loud snort or choking sound.
Frequent drops in your blood oxygen level and reduced sleep quality can trigger the release of stress hormones. These hormones raise your heart rate and increase your risk for high blood pressure, heart attack, stroke, and arrhythmias (irregular heartbeats). The hormones also can raise your risk for, or worsen, heart failure.
Untreated sleep apnea also can lead to changes in how your body uses energy. These changes increase your risk for obesity and diabetes.
Sleep Apnea Research: The HeartBeat Study
Living With and Managing Sleep Apnea
05/18/2011
Sleep Disorders & Insufficient Sleep: Improving Health through Research
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National Institutes of Health- (NIH) supported research is shedding light on how sleep and lack of sleep affect the human body. The NIH and its partners will continue to work together to advance sleep research. Read the full fact sheet...
Clinical trials are research studies that explore whether a medical strategy, treatment, or device is safe and effective for humans. To find clinical trials that are currently underway for Sleep Apnea, visit www.clinicaltrials.gov.
May 21, 2013
Tonsil surgery improves some behaviors in children with sleep apnea syndrome
Children with sleep apnea syndrome who have their tonsils and adenoids removed sleep better, are less restless and impulsive, and report a generally better quality of life, finds a new study funded by the National Institutes of Health. However, the study found cognitive abilities did not improve compared with children who did not have surgery, and researchers say the findings don’t mean surgery is an automatic first choice.
The NHLBI updates Health Topics articles on a biennial cycle based on a thorough review of research findings and new literature. The articles also are updated as needed if important new research is published. The date on each Health Topics article reflects when the content was originally posted or last revised.