What Is Sleep Apnea — and Could You Have It?

What are the two main types of sleep apnea?

Obstructive sleep apnea (OSA) is by far the most common form. During sleep, the throat muscles relax more than usual, partially or fully collapsing the airway. The brain senses the oxygen drop and briefly rouses you enough to reopen it — a micro-arousal you rarely remember. This cycle can repeat many times an hour throughout the night, fragmenting sleep without you knowing.

Central sleep apnea (CSA) is less common and works differently: the airway is physically open, but the brain does not consistently send the signal to breathe. It is more often associated with heart failure, opioid use, or high altitude, and is less likely to be the kind someone would self-suspect.

What are the classic signs — and why are they easy to miss?

The hallmark symptoms of OSA include:

• Loud, habitual snoring, sometimes punctuated by silence and then a snort or gasp
• Waking with a dry mouth, sore throat, or headache
• Feeling unrefreshed after a full night's sleep — regardless of how long you were in bed 1Ref 1Watson NF, Badr MS, Belenky G, et al. (2015).Recommended Amount of Sleep for a Healthy Adult: A Joint Consensus Statement of the American Academy of Sleep Medicine and Sleep Research Society.Context for unrefreshing sleep as a departure from normal sleep quality expectations
• Excessive daytime sleepiness: falling asleep in quiet situations, difficulty concentrating, irritability
• Frequent nighttime urination

Because the arousals are brief and unconscious, many people have no idea they are happening. A common discovery path is a bed partner who noticed the pattern, or a clinician screening after someone mentioned persistent tiredness.

Why does untreated sleep apnea matter beyond feeling tired?

Untreated OSA is not just an inconvenience. Repeated oxygen drops and sleep fragmentation strain the cardiovascular system over time, raising the risk of high blood pressure, heart disease, atrial fibrillation, and stroke 2Ref 2Itani O, Jike M, Watanabe N, Kaneita Y (2017).Short Sleep Duration and Health Outcomes: A Systematic Review, Meta-analysis, and Meta-regression.Cardiovascular and metabolic consequences of disrupted sleep, including links to hypertension and cardiometabolic disease. It also worsens blood sugar control, contributes to depression, and impairs driving and workplace performance in ways that are easy to attribute to something else. This is why evaluation matters — not just for tonight's sleep, but for longer-term health.

How is sleep apnea diagnosed?

Diagnosis requires a sleep study. For most people with suspected obstructive sleep apnea, a home sleep apnea test (HSAT) — a portable overnight monitor worn at home that tracks breathing effort, airflow, oxygen levels, and heart rate — is sufficient 3Ref 3Kapur VK, Auckley DH, Chowdhuri S, et al. (2017).Clinical Practice Guideline for Diagnostic Testing for Adult Obstructive Sleep Apnea: An American Academy of Sleep Medicine Clinical Practice Guideline.Home sleep apnea testing vs. polysomnography, CPAP as first-line treatment, Epworth Sleepiness Scale use in clinical evaluation. For more complex situations (suspected central apnea, multiple conditions, or an inconclusive HSAT), an in-lab polysomnography measures brain waves, eye movements, muscle activity, heart rhythm, and oxygen in addition to breathing.

A clinician may also use the Epworth Sleepiness Scale, a validated questionnaire that quantifies daytime sleepiness and helps assess severity 3Ref 3Kapur VK, Auckley DH, Chowdhuri S, et al. (2017).Clinical Practice Guideline for Diagnostic Testing for Adult Obstructive Sleep Apnea: An American Academy of Sleep Medicine Clinical Practice Guideline.Home sleep apnea testing vs. polysomnography, CPAP as first-line treatment, Epworth Sleepiness Scale use in clinical evaluation.

What are the treatment options?

Treatment depends on severity and type:

• CPAP (continuous positive airway pressure): The most effective treatment for moderate to severe OSA — a mask worn during sleep that keeps the airway open with gentle pressurized air. Many people start skeptical and become strong advocates once they feel the difference 3Ref 3Kapur VK, Auckley DH, Chowdhuri S, et al. (2017).Clinical Practice Guideline for Diagnostic Testing for Adult Obstructive Sleep Apnea: An American Academy of Sleep Medicine Clinical Practice Guideline.Home sleep apnea testing vs. polysomnography, CPAP as first-line treatment, Epworth Sleepiness Scale use in clinical evaluation.
• Oral appliance: A custom mouthpiece made by a dentist that repositions the jaw; appropriate for mild to moderate OSA or those who cannot tolerate CPAP.
• Positional therapy: For people whose apnea is significantly worse when sleeping on their back, positional devices encourage side-sleeping.
• Weight management: Excess weight, particularly fat around the neck and upper airway, substantially increases OSA risk. Weight loss is one of the most effective treatments for mild to moderate OSA.
• Surgery: Reserved for specific anatomical contributors (e.g., enlarged tonsils, nasal obstruction) when other approaches have not worked.

Alcohol close to bedtime worsens apnea by relaxing throat muscles and suppressing the arousal response — avoiding it meaningfully reduces severity for many people 4Ref 4Ebrahim IO, Shapiro CM, Williams AJ, Fenwick PB (2013).Alcohol and Sleep I: Effects on Normal Sleep.Alcohol relaxes throat muscles, suppresses arousal from apneas, and worsens OSA severity.

What factors increase the risk of sleep apnea?

Several factors increase the likelihood of OSA:

• Body weight and neck circumference: Larger neck size and excess upper-body fat are among the strongest risk factors.
• Sex and hormonal status: OSA is more common in men and in post-menopausal women. Estrogen and progesterone appear to have a protective effect on airway muscle tone.
• Sleeping position: OSA is often worse lying on your back.
• Nasal anatomy: Chronic congestion, a deviated septum, or enlarged tonsils all contribute to airway collapse during sleep.
• Opioid or sedative medications: These can worsen existing OSA and contribute to central apnea. Always tell your clinician about these medications 3Ref 3Kapur VK, Auckley DH, Chowdhuri S, et al. (2017).Clinical Practice Guideline for Diagnostic Testing for Adult Obstructive Sleep Apnea: An American Academy of Sleep Medicine Clinical Practice Guideline.Home sleep apnea testing vs. polysomnography, CPAP as first-line treatment, Epworth Sleepiness Scale use in clinical evaluation.