Influence of maxillary constriction on nasal resistance and sleep apnea severity in patients with Marfan's syndrome

Background: Marfan's syndrome is associated with a high prevalence of obstructive sleep apnea (OSA). As this syndrome is associated with a characteristic constricted maxilla and high-arched palate, we reasoned that nasal airway constriction and resultant high nasal airway resistance (NAR) may contribute to the development of OSA. Therefore, the aim of this study wa to measure. NAR in patients with Marfan's syndrome. In addition, we aimed to examine the influence of maxillary morphology on both NAR and the severity of OSA. Method: We measured NAR in 13 consecutive patients with Marfan's syndrome and 13 control subjects. NAR was measured by posterior rhinomanometry, and expressed as the inspiratory resistance at a flow of 0.5 L/s. Dental impressions were taken to evaluate maxillary arch morphology, allowing measurement of the following distances: intercuspid (ICD), interpremolar (IPD), intermolar (IMD), and maximum hard palate height (MPH). Ten of the patients and four of the control subjects had previously undergone nocturnal polysomnography. Results: Mean NAR for the Marfan group was more than twice that in the control group (7.7+/-1.2 vs 2.9+/-0.4 cm H2O/L/s; p<0.005). The patients also had marked constriction of the maxillary arch compared with control subjects. Two of the lateral maxillary measurements were significantly inversely correlated with NAR. There were significantly correlations between various maxillary arch measurements (MPH/ICD, MPH/IPD, MPH/IMD) and the apnea/hypopnea index. Conclusions: These data suggest that high NAR is a common feature of Marfan's syndrome. Maxillary constriction with a relatively high hard plate appears to be a major reason for the high NAR. The significant correlations between indexes of maxillary constriction and sleep apnea severity suggest that maxillary morphology may play an important role in the pathophysiology of OSA in Marfan's syndrome.