Sleep apnea may be tied to tongue fat, study finds

Study identifies a fat tongue as a primary factor in the common sleep disorder.

January 10, 2020, 10:54 AM

This is an Inside Science story.

(Inside Science) -- Obstructive sleep apnea is a common disorder in which people stop breathing in their sleep due to blockage of their upper airway. A recent paper published in the American Journal of Respiratory and Critical Care Medicine has singled out the main culprit behind this blockage -- a fat tongue.

Obesity has long been linked with obstructive sleep apnea. The study sought to pinpoint what exactly is causing this obstruction of the airway. The researchers performed MRI scans on 67 participants with obstructive sleep apnea, before and after the patients underwent diet regimens or weight-loss surgery to help with the sleep disorder. On average, the participants lost nearly 10% of their body weight over six months, which resulted in a 31% improvement in sleep apnea.

The MRI images showed a reduction in tongue fat volume as the primary link between weight loss and sleep apnea improvement. They also found correlations between sleep apnea improvement and a reduction in the size of certain muscles -- namely, a jaw muscle used for chewing, known as the pteroid, and muscles on the sides of the airway known as the pharyngeal lateral wall -- but not to the same extent as a reduction in tongue fat.

PHOTO: A man wears a mask for the treatment of sleep apnea in an undated stock photo.
A man wears a mask for the treatment of sleep apnea in an undated stock photo.
STOCK PHOTO/Getty Images

The researchers suggest future studies should explore whether certain diets or therapeutic treatment techniques can aid in reducing tongue fat for treating sleep apnea. They also explored the role genetics may play in causing sleep apnea, and suggested that people of certain ethnicities may be predisposed to having fattier tongues.

According to study leader Richard Schwab from the University of Pennsylvania’s School of Medicine, patients who suffer from snoring or sleepiness should be checked for sleep apnea.

"Primary care doctors, and perhaps even dentists, should be asking about snoring and sleepiness in all patients, even those who have a normal body mass index, as, based on our data, they may also be at risk for sleep apnea," Schwab said in a press release.

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