In the face of criticism from insurers and the government for a perceived excessive zeal for profits, and mounting evidence that uncomplicated obstructive sleep apnea (OSA) can be diagnosed at home and managed by primary physicians, you can't blame sleep specialists for feeling down-in-the-mouth lately. Sushmita Pamidi et al report some brighter news in the January 2012 CHEST: referring patients to see a sleep specialist before making the diagnosis of sleep apnea was associated with increased adherence to continuous positive airway pressure therapy (CPAP).
It was a single-center study at the University of Chicago, including 403 patients, all of whom were diagnosed with OSA after a diagnostic polysomnogram (PSG). The difference was who saw them first and ordered the diagnostic PSG: nonsleep specialists referred 298 patients, and sleep specialists referred 105.
Using the typical spyware installed on all modern CPAP machines, the patients' adherence with therapy for the first 30 days was recorded and the groups (sleep-physician-referred and non-sleep-physician-referred) were compared. Those who were first seen by sleep specialists used CPAP an average of 4.7 hours per night, one hour more than those patients diagnosed by non-sleep-specialists, who wore CPAP only 3.7 hours per night. The association was strong after adjusting for available covariates.
Authors' best explanation for this is better counseling by the sleep specialists. They don't describe doing anything special -- other than spending 45 to 60 minutes with each new patient and actually telling them all about OSA and CPAP, which probably does qualify as special, come to think of it. I wouldn't / couldn't do that in a standard patient visit, and few time-constrained primary doctors could be expected to.
In this study, race was also a strong predictor of CPAP adherence. African-American patients (54% of the cohort) were much less likely to consistently use CPAP, on average wearing it about an hour less per night. Patients are disdainful of CPAP generally: only a minority consistently use the machine 4 hours per night, the generally-accepted point at which clinical benefits accrue. This poor adherence is an increasingly annoying thorn in the side of the insurers paying for devices and DME companies providing them; they're starting to send out the CPAP Repo Man to take back machines from patients who they believe aren't wearing CPAP often or long enough.
Clinical Takeaway: This was a single-center study, so let's not get too excited. But the idea that pre-polysomnography counseling by a sleep specialist would improve CPAP adherence in people with OSA certainly makes sense and might be true more generally, at other places besides U. of C. Maybe someone will look into that for us -- ideally someone with access to a giant database of real-world, community practice like Kaiser, Mayo or Partners.
Pamidi S et al. The Impact of Sleep Consultation Prior to a Diagnostic Polysomnogram on Continuous Positive Airway Pressure Adherence. CHEST 2012;141:51-57.