Intermandibular Width as a Novel Anthropometric Measure for Assessing Obstructive Sleep Apnea Risk

Miriam Klar 1,2 Hillel Maresky 1,2,3 Sigal Tal 1,2
1Radiology, Assaf Harofeh Medical Center, Israel
2Sackler Faculty of Medicine, Tel Aviv University, Israel
3Medical Imaging, Sunnybrook Health Sciences Center, University of Toronto, Canada

PURPOSE: Obstructive sleep apnea (OSA) is associated with severe long-term effects if not diagnosed and treated. Craniofacial abnormalities are a known risk factor, but the specifics of it are still under investigation and need to be better characterized. This study investigates the relationship between mandibular width and the risk of developing OSA.

METHODS: A retrospective cohort study of all patients undergoing head and neck CT scans taken between January 2013 and December 2013. Patients below 18 years of age, or with unreconstructable scans, and those unable to be contacted to complete the survey were excluded from the study. 3D CT reconstructions were used to measure mandibular width, neck circumference, neck fat volume (NFV), airway volume (AWV), and NFV:AWV ratio. Age, gender, and BMI were also documented. Patients were contacted to complete a STOP-BANG survey to assess OSA risk. Survey results were analyzed to assess the correlation between mandible width and STOP-BANG. Mandible association was also compared to the associations of the other known risk factors.

RESULTS: A total of 427 patients with a mean age of 58.98 years (standard deviation = 16.77), 56% of whom were male, were therefore included in the final study analysis. Mandibular width was found to positively correlate with STOP-BANG score (r = .416, p <.001). Furthermore, when stratified according to mandible size, the small mandible group (84.40 mm) was predominantly seen in high risk patients. Mandible width expressed a stronger association than NFV:AWV ratio, but neck circumference and NFV had stronger associations than did mandible width.

CONCLUSION: In addition to previously documented OSA risk factors, we identify mandibular width as a positively correlated risk factor for the development of OSA. Observation of a wide mandible (jaw) should raise awareness of OSA risk and increase screening methods when appropriate.

Miriam Klar
Miriam Klar