Abstract
Objective: The aim of this study was to investigate the potential relationship between the volumetric area of the upper airway and rheumatoid arthritis (RA) by comparing upper airway measurements between patients with and without RA. Methods: This case-control study compared upper airway measurements between patients with and without RA using lateral cephalometric radiographs. Two distinct measurements were made: the area of the upper airway, which is defined as "the area extending from the point of the retro-palatal region to the base of the epiglottis," and the distance of the upper airway, which is defined as "the distance between the anterior border of the third cervical vertebra (C3) and the anterior border of the soft tissue of the neck". A single examiner performed all measurements, and the intra-examiner reliability was assessed. Results: Sixty-one RA patients and 95 non-RA patients were included in the case and control groups, respectively. RA patients were significantly older in age and with higher BMI values. Patients with or without RA had Angle Class II as the most prevalent orthodontic classification. The upper airway was slightly narrower in RA patients, resulting in a smaller area, and the length of the upper airway was significantly longer in RA patients. Conclusion: Patients with RA have narrower upper airways as measured on lateral cephalometric radiographs. This may partially explain the high prevalence of obstructive sleep apnea among patients with RA. Focusing on airways measurements when cephalometric radiographs are taken for patients with RA could give some idea about which patient is likely to have OSA.