Class act is a feature of Clinical Correlations written by NYU 3rd and 4th year medical students. These posts focus on evidenced based answers to clinical questions related to patients seen by our students in the clinics or on the wards. Prior to publication, each commentary is thoroughly reviewed for content by a faculty member. Enjoy…
Commentary by Andrew Kleinberger, NYU Medical Student
Obstructive Sleep Apnea (OSA) is a syndrome of sleep-disordered breathing that has gained a great deal of attention over the past decade within the sphere of primary care. Most commonly linked to risk factors such as obesity, smoking, diabetes mellitus, and structural abnormalities of the upper aerodigestive tract, OSA is an important contributor to overall morbidity and mortality. Specifically, studies show an association between OSA and systemic and pulmonary hypertension, cardiovascular and cerebrovascular events, and cardiac arrhythmias (1). These long-term sequelae exist in addition to the more common adverse effects of OSA such as excessive snoring, daytime fatigue, moodiness, and poor concentration.
Depending on the definition used, roughly 10-20% of the population meets the criteria for OSA. However, many patients remain undiagnosed and even when identified, they often go untreated (2). While many disorders can be managed effectively with medications, OSA often requires the use of nightly respiratory masks (i.e. continuous positive airway pressure or CPAP), craniofacial manipulation devices, or even surgery (typically performed by an Otolaryngologist). Pharmacologic therapies can be employed as adjuncts to conventional treatments, but there is insufficient evidence to support their role as primary agents (3).
As may be expected by the current invasive therapies, patient compliance with standard treatments for OSA is poor. Interventions impose physical and financial burdens on both the patient as well as the healthcare system. Of greatest importance, the actual efficacy of many OSA therapies in improving long-term outcomes is still under investigation. As such, the management of patients with OSA can present a challenge for primary care physicians. Specifically, when is surgery indicated for a patient with OSA and which procedures have proven most effective?
With recent advancements in technology, the range of surgeries performed for patients with OSA has dramatically increased. One of the most common procedures to relieve obstruction in adults is uvulopalatopharyngoplasty (UPPP) in which excessive soft tissue of the oropharynx is removed. Surgeries addressing other upper aerodigestive tract abnormalities have been employed as well; these include nasal septoplasty and turbinectomy, adenotonsillectomy, soft palatal implants, tongue-base reduction, thyrohyoid suspension, maxillofacial advancement, and, in extreme cases, tracheotomy. While these surgeries have gained greater recognition as the structural contributions to OSA are discovered, the absolute efficacy of surgical modification has yet to be firmly established.
A retrospective study conducted in the 1980’s to investigate the effectiveness of UPPP found significant clinical improvement in only 25% of patients, mostly with moderate OSA, while the procedure failed in just over half of cases (4) A more recent study assessed the long-term outcomes of patients with OSA undergoing UPPP with a mean follow-up of four to eight years. The results demonstrated a sustained effect in over half of patients treated and concluded that the procedure can be beneficial for mild or moderate OSA, but close monitoring is necessary because post-op relapses can occur (5). Another study published in Laryngoscope, with an average follow-up of almost three years, initially showed both subjective and objective improvements in over half of the population; however, these responses were found to decrease over time (6).
Studies for relatively less invasive approaches to the soft palate such as electrocautery, laser-assisted surgery, and implantable pillars have also yielded mixed results (7). Other previously mentioned procedures such as suspensions and advancements have been supported to varying degrees by the literature. However, they carry greater risk and neither study size nor long-term follow-up has been sufficient to draw significant conclusions (8). A promising surgery with fair literature support is that of adenotonsillectomy. This procedure is the most common surgery performed for children with sleep-disordered breathing and a recent study demonstrated substantial post-operative improvements in both polysomnography parameters and quality of life for the majority of healthy children (9).
Despite a host of recent relevant publications, the indications for and efficacy of surgery for OSA remains controversial as sufficient head-to-head comparisons of surgical and non-surgical approaches have yet to be performed (10). A cohort study from Taiwan followed over 100 patients after either CPAP use or UPPP and assessed outcomes at 6 months and 3 years. The authors subsequently concluded that while surgery initially had a greater benefit on snoring, this effect dissipated over time. In terms of objective sleeping measures and quality of life, the efficacy of both modalities was considered essentially equivocal (11). Overall, it has proven difficult to conduct such studies due to issues with randomization, lack of blinding and compliance with therapy, as well as reliance on subjective outcome assessment.
As for current indications, studies support the use of upper airway surgery as second-line treatment in selected patients with OSA who fail a trial of conventional CPAP (12). In general practice, surgery is now performed in cases with a compelling anatomical obstruction, severe OSA refractory to conservative therapy, or if the patient is unable to tolerate CPAP or oral appliances. This decision should be made carefully with consideration for disease severity, patient preference, and the potential risks of the proposed intervention.
References:
1. Parish, JM, Somers, VK. Obstructive sleep apnea and cardiovascular disease. Mayo Clin Proc 2004; 79:1036.
2. Netzer, NC, et al., Prevalence of symptoms and risk of sleep apnea in primary care. Chest 2003; 124:1406.
3. Hudgel, D, Thanakitcharu, S. Pharmacologic treatment of sleep-disordered breathing. Am J Respir Crit Care Med 1998; 158:691.
4. DeBerry-Borowiecki B, Kukwa AA, Blanks RH. Indications for palatopharyngoplasty. Arch Otolaryngol 1985 Oct; 111(10):659-63.
5. Janson C, Gislason T, Bengtsson H, et al. Long-term follow-up of patients with obstructive sleep apnea treated with uvulopalatopharyngoplasty. Arch Otolaryngol Head Neck Surg 1997 Mar; 123(3):257-62.
6. Boot H, vanWegen R, Poublon RM, et al. Long-term results of uvulopalatopharyngoplasty for obstructive sleep apnea syndrome. Laryngoscope 2000 Mar; 110(3 Pt 1):469-75.
7. Goessler UR, Hein G, Verse T, et al. Soft palate implants as a minimally invasive treatment for mild to moderate obstructive sleep apnea. Acta Otolaryngol 2007 May; 127(5):527-31.
8. Dattilo DJ, Drooger SA. Outcome assessment of patients undergoing maxillofacial procedures for the treatment of sleep apnea: comparison of subjective and objective results. J Oral Maxillofac Surg 2004 Feb; 62(2):164-8.
9. Mitchell RB. Adenotonsillectomy for obstructive sleep apnea in children: outcome evaluated by pre- and postoperative polysomnography. Laryngoscope 2007 Aug 23 (print pending).
10. Sundaram, S, Bridgman, SA, Lim, J, et al. Surgery for obstructive sleep apnea. Cochrane Database Syst Rev 2005; CD001004.
11. Lin SW, Chen NH, Li HY, et al. A comparison of the long-term outcome and effects of surgery or continuous positive airway pressure on patients with obstructive sleep apnea syndrome. Laryngoscope 2006 Jun; 116(6):1012-6.
12. Souter MA, Stevenson S, Sparks B, Drennan C. Upper airway surgery benefits patients with obstructive sleep apnea who cannot tolerate nasal continuous positive airway pressure. J Laryngol Otol 2004 Apr; 118(4):270-4.
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