Predictors of obstructive sleep apnea

Abstract

A patient’s condition, such as obesity, plays a key role in the pathophysiology of obstructive sleep apnea (OSA). This study focuses on morphometric data that might be associated with the apnea–hypopnea index (AHI) and could therefore be used to predict OSA in order to better select patients for cardiorespiratory polysomnography (PSG). Data of 110 patients with suspected OSA in the sleep center outpatient department were analyzed retrospectively. The data included morphometric measurements such as neck, waist, and hip circumference; weight; body size; age; and Epworth Sleepiness Scale (ESS). The results of the patients’ overnight polygraphy, the AHI, completed the data. Neck and waist circumference can predict the AHI (p < 0.01). Power of prediction was higher for both factors among male (p < 0.01) compared to female patients (p = 0.05). In the case of neck circumference, the threshold value is 40 cm. Neck circumferences of more than 40 cm are strongly associated with a higher AHI (p < 0.001). It was possible to confirm the roles of waist and neck circumference as important parameters for a prediction model. Nevertheless, these parameters alone are not precise enough to completely neglect factors such as anatomic morphology in order to predict OSA and its severity.