RELATED: If You Do This at Night, It May Be an Early Sign of Parkinson’s, Study Says. According to Kannan Ramar, MBBS, MD, a sleep medicine specialist and pulmonologist with the Center for Sleep Medicine at the Mayo Clinic, having an abnormally large neck is linked with a higher likelihood of having obstructive sleep apnea (OSA). Specifically, men with a neck circumference (NC) over 17 inches and women with a neck circumference over 16 inches are most likely to have developed the condition. “In most people, a neck size greater than 16 or 17 inches is a sign of excess fat in the neck area,” Ramar wrote in a Mayo Clinic Health Letter. “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,” he explains. In fact, some studies have found that neck circumference is one of the best predictors of OSA—more reliable than body mass index (BMI), which was once thought to be the most significant risk factor. “As neck thickness is an important indicator of OSA, the measurement of neck circumference has become standard practice in the current physical examination when there is suspicion of sleep apnea,” says a 2021 study published in the journal Diagnostics. “Other studies concluded that a big NC (adjusted to patient’s height) is considered as the most predictable clinical sign of OSA, coming close to 77 percent sensitivity and 82 percent specificity, and is the most significant factor that determines the clinical outcome of sleep apnea,” the researchers write. RELATED: If You’re Sweating at Night, It Could Be a Sign of These Kinds of Cancer. Though many people who have sleep apnea are unaware that they have the condition, experts warn that it can cause potentially serious medical consequences. “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,” notes Ramar.ae0fcc31ae342fd3a1346ebb1f342fcb Additionally, OSA has been identified as an independent risk factor for stroke, abnormal glucose metabolism, arrhythmia, left ventricular dysfunction, heart disease, and pulmonary hypertension, says the Diagnostics study. “Sleep apnea is further associated with higher mortality incidence caused by accidents, and cardiovascular diseases,” those researchers write, noting that sleep apnea may also be linked to increased cancer risk. Though neck circumference is now widely considered a reliable risk factor for sleep apnea, experts note that it’s just one among many. For this reason, your doctor will need to evaluate your symptoms with a comprehensive set of tests, and will likely probe your health history and data for more information. “Doctors use neck circumference and other indicators to evaluate your overall risk of OSA,” writes Ramar. “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,” he adds. If a diagnosis is not immediately clear, your doctor may recommend an at-home, overnight study to track your oxygen levels while you sleep. In rarer cases still, you may be asked to complete a study in a sleep clinic or lab, to determine whether OSA is the cause of your symptoms, and to pinpoint a course of treatment. For more health news sent directly to your inbox, sign up for our daily newsletter. According to the Centers for Disease Control and Prevention (CDC), there are typically two forms of treatment for OSA. In one course, your doctor may seek to treat the underlying cause for your sleep apnea if one has been identified—for instance, congestive heart failure or nasal obstruction. In the other course of treatment, your doctor would address your symptoms themselves. The CDC says that by administering gentle air pressure using a continuous positive airway pressure (CPAP) device, you may notice fewer disruptions to your breathing while asleep. “Another option is a mouthpiece to thrust your lower jaw forward during sleep. In some cases, surgery might be an option too,” adds the Mayo Clinic. The CDC urges that symptoms of sleep apnea always warrant an evaluation from your medical provider. “As interruption of regular breathing or obstruction of the airway during sleep can pose serious health complications, symptoms of sleep apnea should be taken seriously,” they warn. Speak with your doctor if you notice symptoms of sleep apnea, including excessive daytime sleepiness or fatigue, sudden waking, headache upon waking, dry mouth or throat, and of course, an abnormally large neck size. RELATED: If You Can’t Stop Doing This at Night, Get Your Thyroid Checked.