Objectives: We wanted to evaluate whether the presence of nasal obstruction makes a change on the association between the modified Mallampati score and the severity of sleep-disordered breathing (SDB) and the sleep quality.
Methods: Polysomnography (PSG), the modified Mallampati score (MMS), the body-mass index, and a questionnaire about nasal obstruction were acquired from 275 suspected SDB patients. The subjects were divided into two groups according to the presence of nasal obstruction. The clinical differences between the two groups were evaluated and the associations between the MMS and PSG variables in each group were also assessed.
Results: Significant correlations were found between the MMS and many PSG variables, including the apnea-hypopnea index, the arousal index and the proportion of deep sleep, for the patients with nasal obstruction, although this was not valid for the total patients or the patients without nasal obstruction.
Conclusion: The severity of SDB and the quality of sleep are well correlated with the MMS, and especially for the patients with nasal obstruction. The MMS can give more valuable information about the severity of SDB when combined with simple questions about nasal obstruction.
Keywords: Modified Mallampati score; Mouth breathing; Nasal obstruction; Sleep apnea syndrome; Sleep disordered breathing.