CPAP Alternatives Gaining Steam for Sleep Apnea : Suboptimal CPAP compliance is spurring greater use of oral appliances, maxillofacial surgery.
Maxillofacial Surgery
Maxillomandibular advancement is a big operation, and it yields big results, said Dr. Kasey Li of Stanford (Calif.) University.
Dr. Li cited a recent meta-analysis that included a total of 627 patients who underwent maxillomandibular advancement (MMA).
Their mean AHI dropped from 63.9 to 9.5 events/hour. Treatment success, defined as an AHI below 20, occurred in 86% of patients. A surgical cure, meaning an AHI below 5, was obtained in 43% of patients (Sleep Med. Rev. 2010 [doi:10.1016/j.smrv.2009.11.003]).
This parallels Dr. Li's personal experience, which includes 302 patients with pre- and post-MMA sleep data. The operation typically takes about 3 hours, with a 2- to 3-day hospital stay and return to work in 4-5 weeks.
As in the meta-analysis, there have been no postoperative deaths in Dr. Li's own series. The most common side effect is cranial nerve paresthesia, which typically resolves within 6-12 months. Four of Dr. Li's patients had severe malocclusion requiring revision surgery. Ninety percent of patients report being satisfied with their results.
A multivariate regression analysis done as part of the meta-analysis identified four significant predictors of increased likelihood of MMA success: younger age, lower body mass index, less severe sleep apnea, and greater degree of maxillary advancement. This mirrors Dr. Li's experience as well.
“My enthusiasm for offering surgery to patients over age 60 goes down quite a bit. I'm fairly reluctant to offer surgery to patients with a BMI of 32-33 kg/m
Patients who have failed on oral appliances remain reasonable candidates for surgery.
“The average advancement with an oral appliance is 4-7 mm, in comparison to 15-16 mm of maxillary advancement measured at the teeth level with surgery, in my experience,” Dr. Li noted.
When asked if it makes sense to perform a less morbid soft tissue surgical procedure such as tonsillectomy or uvulopalatopharyngoplasty as a first-line operation for patients with moderate to severe OSA, reserving MMA for the nonresponders, Dr. Li's answer was emphatically no.
“In the majority of patients, the entire airway is involved; the obstruction is at multiple levels. Surgical procedures that focus on one site often will not be successful,” he said.
“The data over the past 10 years are very clear that patients with severe sleep apnea are not going to respond very well to soft tissue surgery, period. I tell patients that unless they're going to have MMA, they shouldn't bother with surgery. That's my personal bias, and I think it's supported by the data,” he added
A prospective study that will compare MMA with CPAP is in the planning stages at Stanford.
Weight Loss
Too many physicians are jaded about this well-established but seriously underused treatment for OSA, according to Dr. Ronald R. Grunstein, professor of sleep medicine at the University of Sydney.
“I think we need to have a less nihilistic view about weight loss. We in sleep medicine are often still thinking very much in silos,” he said.
Dr. Grunstein was first author of a large study with a 2-year follow-up period that demonstrated bariatric surgery to be a highly effective treatment for OSA in obese patients (Sleep 2007;30:703-10).
In addition, recent studies conducted in Finland (Am. J. Respir. Crit. Care Med. 2009;179:320-7) and Sweden (BMJ 2009;339:b4609) have shown substantial improvement in OSA with weight loss achieved through a very-low-calorie diet plus exercise followed by a maintenance diet.
The bigger the weight loss, the greater the improvement in OSA as reflected in the reduction in AHI.
Promising pharmacologic alternatives to CPAP are also in development, and not all are weight-loss drugs.
Disclosures: Dr. Lowe is the inventor of the Klearway oral appliance, the royalties for which are assigned to the University of British Columbia, where they pay for much of his research. Dr. Walsh is a consultant to Ventus Medical Inc., which markets the Provent sleep apnea therapy device, which uses nasal expiratory positive airway pressure. Dr. Li and Dr. Grunstein reported no financial conflicts.
'I'm not at all trying to suggest [CPAP] therapy is totally ineffective, but I would term it highly suboptimal.'
Source DR. WALSH
Oral appliances typically show an 80% success rate if the baseline apnea-hypopnea index is below 30 episodes/hour.
Source DR. LOWE
The mean apnea-hypopnea index dropped from 63.9 to 9.5 events/hour after maxillomandibular advancement.
Source DR. LI
