CPAP introduction:
An implant for obstructive sleep apnea — a serious sleep malady in which breathing stops for 10 seconds to two minutes many times an hour each night — works best in people who are overweight but not severely obese, a new study found.
To qualify for the device, called a hypoglossal nerve stimulator, a person over 18 diagnosed with moderate-to-severe obstructive sleep apnea must be unable to adapt or refuse to wear a continuous positive airway pressure, or CPAP, machine, the gold standard treatment for obstructive sleep apnea.
CPAP stands for Continuous Positive Airway Pressure. It is a non-invasive medical treatment commonly used for individuals with sleep apnea, a condition characterized by interrupted breathing during sleep.
A CPAP machine delivers a constant flow of air pressure through a mask worn over the nose or both the nose and mouth. The air pressure helps keep the airways open, preventing pauses in breathing and ensuring a continuous oxygen supply throughout the night. By maintaining a steady airflow, CPAP effectively reduces or eliminates snoring, improves sleep quality, and alleviates the symptoms of sleep apnea.
CPAP machines typically consist of a motor that generates airflow, a humidifier that adds moisture to the air to prevent dryness, a mask or interface that fits over the face, and tubing that connects these components. The machine can be adjusted to deliver the appropriate air pressure prescribed by a healthcare professional based on the severity of the individual's sleep apnea.
It's important to note that CPAP therapy requires a diagnosis of sleep apnea and a prescription from a qualified healthcare provider. The specific settings and adjustments of the CPAP machine should be determined by a sleep specialist or respiratory therapist to ensure its effectiveness and safety for the individual using it.
CPAP replacement works well for the overweight, not obese, study finds.
The new study, published Thursday in the journal JAMA Otolaryngology — Head & Neck Surgery, looked at the body mass index of 76 patients who had received the implant, said senior author Dr. Eric Landsness, an assistant professor of neurology and sleep medicine at Washington University School of Medicine in St. Louis.
Currently, the implant surgery, which costs between $50,000 and $100,000, is approved and covered by Medicare and many insurance companies for people with a BMI of up to 40.
However, “we found for people with a BMI of more than 32, the device might be unsuccessful up to 75% of the time,” Landsness said. “It was a linear relationship: For each unit increase in BMI beyond 32, the odds of successful treatment decreased by approximately 17%.”
As currently defined, a BMI between 18.5 and 24.9 is a healthy weight, between 25 and 29.5 is overweight, between 30 and 34.9 is obese, between 35 and 39.5 is class 2 obesity, and anything over 40 is “severe” or class 3 obesity, which used to be called morbid obesity. People are considered underweight if their BMI is lower than 18.5.
The study also found the implant was less successful for people who slept on their backs, or what is called the supine position.
Yet many people with the condition have no idea they are denying their brains and bodies life-sustaining oxygen, often going undiagnosed until a sleep partner complains of excessive snoring or gasping during sleep, two telltale signs.
“People wake up just enough to start breathing when this happens but often not enough to regain consciousness,” Landsness said. “They can go on like that for years without realizing why they have a lack of focus, low energy and excessive sleepiness during the day.”
New solutions to treat obstructive sleep apnea are desperately needed, so the stimulator’s advent was welcome news to doctors desperate to offer their patients a solution, Landsness said.
“As an alternative treatment for sleep apnea, this hypoglossal nerve stimulation surgery could revolutionize some people’s lives,” he said. “I’ve had patients cry with joy after they have recovered because they have tried so hard and failed with CPAP, and we finally found something that works for them.
“However, it seems a person’s weight seems to be an important factor that predicts whether or not they will respond successfully to the treatment,” he said. “As a sleep doctor, I want this treatment to be given to patients, but I want it to be given to the right patients, the ones who will benefit the most.”
