Sleep apnea: the warning signs, and why it matters for your heart

Obstructive sleep apnea is one of the most common sleep disorders, and one of the most overlooked. A large 2019 analysis estimated that close to a billion adults worldwide have it, and most of them don’t know.

What happens during sleep apnea

When you sleep, the muscles in your throat relax. In obstructive sleep apnea, the airway narrows or closes completely, again and again, through the night. Each time, oxygen levels drop and the brain briefly wakes you, usually too briefly to remember, so the airway reopens. This can happen dozens of times an hour.

The result is fragmented sleep, even if you spend plenty of hours in bed, and a repeated stress response that pushes up blood pressure.

Warning signs

Many people only find out because a partner notices. Common signs include:

• Loud, regular snoring, often with gasps or choking sounds
• Pauses in breathing that someone else has seen
• Daytime sleepiness, including nodding off while reading, watching TV or, dangerously, driving
• Morning headaches and a dry mouth on waking
• Waking often to urinate at night
• Poor concentration, irritability or low mood
• High blood pressure, particularly if it’s hard to control with medication

Being overweight, having a larger neck, being male, being over 50 and drinking alcohol in the evening all raise the risk. But people of any size and age can have sleep apnea, and women are often diagnosed later because their symptoms are less classic.

Screening with STOP-BANG

STOP-BANG is a quick questionnaire clinicians use to decide who should have a sleep study. It asks about Snoring, Tiredness, Observed pauses in breathing, high blood Pressure, BMI over 35, Age over 50, Neck circumference over 40 cm and male Gender.

A score of 0 to 2 suggests low risk, 3 to 4 intermediate risk, and 5 to 8 high risk of moderate to severe sleep apnea. You can take it in our blood pressure and sleep calculator, alongside your blood pressure reading. A high score isn’t a diagnosis, but it’s a strong reason to ask your doctor about a sleep study.

Why it matters for blood pressure

Untreated sleep apnea is strongly linked with high blood pressure, and it’s one of the most common identifiable causes of resistant hypertension: blood pressure that stays high despite three medications. It’s also associated with heart rhythm problems, stroke and heart failure. More on the connection in short sleep and blood pressure.

Diagnosis and treatment

Diagnosis usually involves a sleep study, either overnight in a sleep lab or with a simpler monitor you wear at home.

The most common treatment is CPAP, a bedside machine that gently blows air through a mask to keep the airway open. Other options include custom oral appliances that hold the jaw forward, positional therapy for people whose apnea happens mainly on their back, weight loss where relevant, and in some cases surgery. Effective treatment usually improves energy within weeks and can lower blood pressure.

Sources

• Benjafield AV, et al. Estimation of the global prevalence and burden of obstructive sleep apnoea: a literature-based analysis. The Lancet Respiratory Medicine. 2019;7(8):687-698.
• Chung F, Abdullah HR, Liao P. STOP-Bang questionnaire: a practical approach to screen for obstructive sleep apnea. Chest. 2016;149(3):631-638.
• Whelton PK, et al. 2017 ACC/AHA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults. Hypertension. 2018;71(6):e13-e115.
• Patil SP, et al. Treatment of adult obstructive sleep apnea with positive airway pressure: an American Academy of Sleep Medicine clinical practice guideline. Journal of Clinical Sleep Medicine. 2019;15(2):335-343.