Elbow Test Could Help Diagnose Sleep Apnea

Does your partner elbow you while you're sleeping because you're snoring too loudly?

This could be a reliable sign that you have sleep apnea, according to researchers from the University of Saskatchewan.

Findings presented at CHEST 2012, the annual meeting of the American College of Chest Physicians, show that asking someone whether they've been elbowed or poked by a partner for snoring or stopping breathing while sleeping is a sign of sleep apnea.

The findings are based on 124 people who went into a sleep disorders lab. They were asked whether they've ever been poked or elbowed due to their snoring, or poked or elbowed because they'd stopped breathing during sleep. Then, they underwent polysomnography (another word for a sleep study, where a person is monitored during their sleep to diagnose sleep disorders).

Researchers took down the participants scores on the apnea–hypopnea index (AHI), which is a measure of the severity of a person's sleep apnea and is determined by how many times a person has a sleep apnea "event" per hour. According to the American Sleep Apnea Association, having an AHI between 5 and 15 (meaning there were 5 to 15 events in an hour) indicates mild sleep apnea; an AHI of 15 to 30 is moderate sleep apnea; and an AHI of 30 or higher is severe sleep apnea.

The researchers found that a person is nearly four times more likely have an AHI score greater than 5 (indicating at least mild sleep apnea) if they said that they've been woken up by a partner for their snoring.

And the likelihood of a person having an AHI score greater than 5 was more than 6 times higher if a person said that they'd been woken up by a partner for having an apneic spell (when a person stops breathing during sleep).

Researchers found that being elbowed for snoring was able to correctly identify sleep apnea 84 percent of the time (a measurement called sensitivity), though it was only able to pick out people who didn't have sleep apnea 41 percent of the time (a measurement called specificity). Meanwhile, being elbowed for breathing cessation during sleep was able to correctly identify sleep apnea 65 percent of the time, and it was able to pick out people who didn't have sleep apnea 77 percent of the time.

"This simple, easy to remember questionnaire significantly improves the pretest prediction of a diagnosis of OSA [obstructive sleep apnea] in the outpatient clinic," researchers wrote in the abstract.

Because the findings have yet to be published in a peer-reviewed journal, they should be regarded as preliminary.