Cause:Obesity; genetic component since often familial (Ann IM 1995;122:174)
Pathophys:Anatomically smaller pharynx predisposes (Nejm 1986;315:1327)
Associated with alcohol use, which worsens apnea, and with hypertension in obese older males; are they cause or effect? (Ann IM 1985;103:190); congestive heart failure (Ann IM 1995;122:487). 1-5% of men age >60 yr; 4% of men age 30-60; 2% of women (Nejm 1993;328:1230)
Sx:Daytime somnolence (in 80%) due to disturbed sleep; history of deep snoring and apneic episodes from roommate; but such hx is only ~65% sens/specif for sleep apnea (Ann IM 1991;115:356); and HT and/or obesity; if 2 of 3 present, sleep apnea will be documented (>5, 10+ sec apneas/h sleep) w 86% sens, 77% specif in general adult primary care population (Ann IM 1999;131:485)
Si:Hypertension (90%) (Jama 2000;283;1829; Nejm 2000;342:1378)
Cor pulmonale; car accident incidence incr × 6 (Nejm 1999;340:847, 881), ASHD and CVAs (Am J Med 2000;108:396)
r/o
Lab: Noninv:Polysomnography (sleep) studies are definitive and probably best 1st test (Ann IM 1999;130:496), positive if >5, 10+ sec apneas/h sleep; if not available, overnight O2 sat monitoring to determine respiratory disturbance index may be helpful (ACP J Club 2005;143:21), esp w autotitrating CPAP machine (Ann IM 2007;146:157)
Rx:
Avoid sleep meds and alcohol
Weight loss, even modest (eg, 20 lb) helps
O2 hs alone decr sleep apnea
Nasal CPAP (Ann IM 2001;134:1015, 1065) helps daytime drowsiness and function if impaired, but not if pt has no complaints even w 30+ apneic spells/h of sleep; helps sx but does not prolong life in pts w CHF (Nejm 2005;353:2025)
Mandibular/tongue advancement devices if CPAP fails
Rarely tracheostomy or uvulopalatopharyngoplasty (ACP J Club 2006;145:43), and/or maxillofacial surgery
Perhaps atrial pacing (Nejm 2002;346:404, 444)