ANSWER: Having a neck circumference that’s greater than 16 inches if you’re a woman or greater than 17 inches if you’re a man is one of numerous risk factors associated with obstructive sleep apnea (OSA). OSA occurs when muscles at the back of your throat relax and temporarily restrict or block airflow as you sleep. This may lead to disrupted sleep and daytime tiredness.
Sudden drops in blood oxygen levels that occur during sleep apnea increase blood pressure and put a strain on your cardiovascular system, raising your risk of developing heart problems such as high blood pressure (hypertension) and heart failure.
In most people, a neck size greater than 16 or 17 inches is a sign of excess fat in the neck area. This may contribute to crowding and narrowing of your breathing tube, making obstruction or blockage of your airway while you sleep all the more likely.
Doctors use neck circumference and other indicators to evaluate your overall risk of OSA. You may be asked questions about how you sleep, whether you snore and how you feel when you’re awake. You also may be assessed for other risk factors such as obesity, high blood pressure, whether you smoke or drink alcohol, or have throat anatomy that crowds your breathing tube.
Your doctor may first recommend an overnight study at home that tests to see if there are periods when your oxygen is low. Depending on the results of that test, your doctor may decide it’s worthwhile for you to spend a night in a sleep lab or to do a home sleep study to definitively diagnose your OSA, determine its severity and assess treatment options. (adapted from Mayo Clinic Health Letter) — Kannan Ramar, MBBS, M.D., Center for Sleep Medicine, Mayo Clinic, Rochester, Minn.