Nasal Obstruction and High Mallampati Score as Risk Factors for Obstructive Sleep Apnea

ABSTRACT: Respiratory sleep disorders are strongly associated with upper airway patency. Nasal obstruction is associated with higher incidences of sleep apnea, primarily by increasing the negative pressure on the airway during inspiration. AIMS: To evaluate the influence of nasal obstruction in the worsening of sleep apnea in patients with OSA and a high score on the modified classification of Mallampati. MATERIALS AND METHODS: We evaluated and classified 206 patients complaining of snoring, and with a past suggestive of OSA through the Modified Mallampati score, Friedman, nasal obstruction and the severity of OSA by AHI. RESULTS: 168 patients who underwent polysomnography were included. Cross-plotting was made comparing the modified Mallampati score, nasal obstruction and AIH. The odds ratio between high Mallampati score and AHI was OR = 5.053, 95% CI = 1.458 to 7.517 (p = 0.0071). High Mallampati score associated with nasal obstruction was correlated with OSAS (p = 0.0227). However the influence of nasal obstruction on the relationship of high Mallampati score and OSA was not significant: OR = 2.850, 95% CI = 0.992 to 8.189. CONCLUSION: The combination of high Mallampati score and nasal obstruction represents a greater risk factor for worsening of OSA.