UCSF

Introduction

Obstructive sleep apnea (OSA) is characterized by breathing disturbances during sleep, and daytime sleepiness.1 Prevalence of OSA has been cited as 3-33% for men and 2-9% for women.2-4 Risk factors for OSA include obesity, male gender, age, neck circumference, high blood pressure, and specific craniofacial anomalies.1,2,5,6 Craniofacial findings in OSA patients include an inferiorly-positioned hyoid relative to the mandibular plane, a relatively shorter maxilla and mandible, larger overjet, an increased mandibular plane angle, and an increased ANB angle.7-10 Our hypothesis is that in an adult orthodontic patient population, specific skeletal cephalometric measurements can distinguish between OSA high-risk and low-risk patients, and that there is a preventive effect of orthognathic surgery in young adulthood for developing OSA later in life.

Materials and Methods

We conducted a cross-sectional study evaluating OSA risk in adult orthodontic and orthognathic surgery patients from the UCSF Orthodontic and Oral and Maxillofacial Surgery clinics. We used a questionnaire composed of the Berlin Questionnaire (BQ), and the Epworth Sleepiness Scale (ESS) to assess the risk of OSA. Each orthodontic subject's lateral cephalogram was digitized. Logistic regression was used to evaluate the association between the subjects' specific cephalometric measurements, and the results of the BQ and ESS.

Results

27 orthodontic subjects and 28 surgical subjects were included. In the orthodontic group, none of the female subjects and 4 of the male subjects scored `high-risk' on the BQ. Male gender (p < 0.05) was found to be significantly associated with being classified as `high-risk' by the BQ in the orthodontic patient group. No difference was found in the BQ and ESS results of the orthodontic and surgical groups. The mandibular plane to hyoid distance (MPH) was found to be moderately associated with being classified as `high-risk' by the BQ (p < 0.1).

Conclusions

1. Our questionnaire serves as an excellent screening tool for orthodontic patients.

2. Prevalence of probable OSA was found to be 40% for males and in 0% of the females in this study's orthodontic patient population.

3. There is a positive association between likelihood of OSA and the following factors: male gender, and an inferiorly-positioned hyoid.