Sleep testing (polysomnography or PSG) to diagnosis obstructive sleep apnea (OSA) is expensive and inconvenient, and may not be easily available to patients in rural or under-resourced settings. Is there another option? A new study is reporting a simple, practical approach for primary care diagnosis of OSA. It involves four questions and a simple, inexpensive test.
The researchers identified 4 independent predictors of OSA and assigned each one a point value:
The total score has 10 points, and a positive screening result was 5 or more points. This clinical rule was 100% sensitive in the development group.
The other part of the screen was an ApneaLink monitor, a simple test to measure blood oxygen via a finger monitor at night. This test had good accuracy using at least 3% oxygen desaturation as the cutoff for an abnormal result.
With the goal of minimizing the need for PSG, the researchers proposed a 2-stage diagnostic model:
This approach was tested prospectively on a validation group, and it had excellent negative predictive value (96% – ability to rule out those who do not have OSA) and moderately good positive predictive value (56% — the ability to predict OSA).
So, here’s how I’ll use the information in our clinic for uninsured patients:
It will be interesting to see if other researchers can replicate this, but for those of us seeing patitents without insurance, this has the potential to be great news.