One of the more heated debates in sleep medicine is the role of surgery for obstructive sleep apnea. There are some sleep doctors that say that there’s no role for surgery at all, except for nasal issues. Then there are physicians who argue that some improvement is better than not using CPAP at all.
Here’s a study that compared non-optimal use of optimal therapy (CPAP) with optimal effect (100%) of non-optimal therapy (surgery). What they found was that the more severe the AHI, the higher percentage of the total sleep time CPAP must be used to significantly reduce the AHI. For example, patients with moderate OSA who use CPAP for 4 hours per night with an effective AHI from 0 to 5 will reduce the average AHI by 33 to 48%.
Medicare’s new guidelines regarding CPAP compliance for coverage requires that you use the CPAP machine at least 4 hours per night for at least 70% of the time over a 30 day period. So if you normally sleep 8 hours, you’ll have to use your CPAP machine at least 35% of your total sleep time (40% if you sleep 7 hours per night) to meet Medicare Guidelines. This doesn’t take into consideration what your average AHI is during the time that you’re using your CPAP.
Since reported non-compliance rates range from 29 to 83%, it’s safe to estimate that about 50% won’t be considered compliant.
The study authors argue that rather than calculating the average AHI only during the time it’s being used, you should also include in the calculation all the sleep times where the patient is not using CPAP. During this time, there’s no improvement at all, so your total average AHI will be significantly lower.
With surgery, however, even if you have mild residual disease, and since your final AHI will remain constant, it will remain at that level during 100% of your sleep times. So the average AHI for the total sleep time can be as good, if not better than CPAP that’s not being used 50% of the time.
This may explain an old VA study that showed that patients who underwent UPPP only had higher survival rates than people placed on CPAP after a few years, but not by much.
While I agree with the basic premise of their paper, there are a few caveats. Many people use their CPAP machines religiously 100% of the time, with an excellent average AHI (less than 5). Clearly, these people should continue with CPAP, and surgery is not an option. However, there are some people who are perfectly happy with CPAP, but wish to be able to come off of it entirely.
Compliance studies are an average measure of large groups of people, and this data can’t be extrapolated to individual situations. As I’ve stated before, there’s a lot more that sleep physicians, ENTs, and DME vendors can do to increase effective CPAP use. But there will alway be some people who try everything with CPAP and just give up. So if this person has an AHI of 59, isn’t an AHI of 11 after suboptimal surgery (which is considered mild sleep apnea) better than staying at 59?
Once surgeons go beyond the soft palate and begin to address the entire upper airway from the nose to the tongue, soft tissue surgical success rates will improve. If you think of obstructive sleep apnea as a craniofacial problem, then it explains why the skeletal framework options (including dental appliances, orthodontic appliances that expand the jaws, and jaw surgery) also work well to significantly lessen the severity of obstructive sleep apnea.
I admit I’m a bit biased being a surgeon, but it’s important to look the practical and real-life aspects of CPAP treatment, and not just the superficial numbers. What are your thoughts on this issue?