Dr Krishna Sundar: Weight Gain May Predispose Patients to Obstructive Sleep Apnea

Age, sex, and body mass index typically drive the development of obstructive sleep apnea, causing encroachment on and collapse of the airway at night, noted Krishna M. Sundar, MD, clinical professor, Pulmonary Division, Department of Medicine, and medical director, Sleep-Wake Center, University of Utah.

Transcript

Why are obstructive and central sleep apnea so prevalent?

Regarding the inherent propensity to obstructive sleep apnea, which is the much more prevalent one, roughly 10% to 30% of the adult population is believed to have some degree of obstructive sleep apnea.

So, we are endowed with a pretty unique airway. We have some of the longest airways, [from] tons of different vertebrate species, and our airway developed so that we could vocalize, which kind of spurred evolution.

There was this period around 40,000, 50,000 years ago, when there was a rapid rate of human evolution even though there was not a dramatic change in fossils’ DNA at that time, and that was believed to be due to acquisition of speech. And so with speech we could communicate and [learn to talk] at a completely different level.

Speech is something which is very unique to our species, especially complex language. And this could only happen because we have a much longer airway. But along with that came also the downside of increased risk for obstructive sleep apnea. There is an inherent propensity, which gets enhanced in people when they gain weight, because then there is more encroachment in the upper airway because of fat. And also with aging, because there seems to be more collapsibility of the airway at night. So age, and it tends to be more in males, because the female hormones seem to have some stabilizing effect on breathing and on the upper airway.

So age, sex, and BMI, or body mass index, are sort of the 3 main drivers. BMI being the most important one amongst these 3.