Nasal resistance in obstructive sleep apnea.

BACKGROUND Acute increases in nasal resistance are known to induce upper airway occlusion in predisposed subjects. With the limited efficacy of nasal surgery alone in the treatment of obstructive sleep apnea (OSA), the relevance of chronically increased nasal resistance in the pathophysiologic features of OSA remains undetermined. METHODS Seventy-one patients with OSA (apnea+hypopnea index > 15 [AHI]) and 70 antisocial snorers (ASS [AHI < 15]) referred for routine assessment of sleep-disordered breathing had concomitant measurement of combined (CNR) and highest unilateral (HUNR) nasal resistance by anterior rhinomanometry. RESULTS Nine individuals (five of 71 in the OSA group and 4 of 70 in the ASS group, 0.5 < p < 0.75) had an abnormally elevated CNR. The HUNR was increased in 21 individuals (11 of 70 in the ASS group and 10 of 71 in the OSA group, 0.25 < p < 0.5). There was no significant difference between CNR in OSA (1.5[0.5]) (mean [SE]) and ASS (1.6 [0.2]) groups. No correlation was found between CNR and the AHI in OSA or in ASS. The Mean HUNR in the OSA group was 5.5 (0.9) (mean [SE]) and in ASS was 5.3(0.6), which were not significantly different (p = 0.89). The HUNR also did not correlate with the AHI in either OSA or ASS. CONCLUSION Chronic changes in nasal resistance are not a significant risk factor for the development or severity of OSA.