The relationship between obesity and craniofacial structure in obstructive sleep apnea.

STUDY OBJECTIVE

To evaluate the interaction between craniofacial structure and obesity in male patients with obstructive sleep apnea (OSA).

DESIGN

Retrospective analysis of a cohort of OSA patients. The relationships between neck circumference (NC), body mass index, apnea severity, and craniofacial and upper airway soft-tissue measurements from upright lateral cephalometry were examined. Patients were divided into groups; small to normal NC (group A), intermediate NC (group B), or large NC (group C).

SETTING

A university teaching hospital and tertiary sleep referral center.

PATIENTS

A consecutive series of patients with OSA who underwent polysomnography and lateral cephalometry.

MEASUREMENTS AND RESULTS

Group A patients were less obese and had more craniofacial abnormalities such as a smaller mandible and maxilla and a more retrognathic mandible. Group B patients had both upper airway soft-tissue and craniofacial abnormalities. Group C patients were more obese with larger tongues and soft palates, and an inferiorly placed hyoid. Group C patients also had fewer craniofacial abnormalities than group A or B patients. There was no difference in airway size among the three groups.

CONCLUSIONS

We conclude that there is a spectrum of upper airway soft-tissue and craniofacial abnormalities among OSA patients: obese patients with increased upper airway soft-tissue structures, nonobese patients with abnormal craniofacial structure, and an intermediate group of patients with abnormalities in both craniofacial structure and upper airway soft-tissue structures.