The role of nocturnal pulse oximetry in the screening for obstructive sleep apnea in obese children and adolescents

Abstract

Background and aim: Obesity is a known risk factor for the development of obstructive sleep apnea (OSA) in children. Early screening is essential because of the possible complications associated with OSA. At present, the gold standard for diagnosing OSA is polysomnography, which however has multiple limitations. The aim of this study is to examine the role of nocturnal oximetry as a screening tool for OSA in obese children and adolescents.

Materials and methods: This retrospective study included obese children who underwent a polysomnography at the Antwerp University Hospital between November 2010 and May 2014. Their oximetries were scored manually, blinded for the polysomnography results, according to Brouilette et al. OSA was defined as an obstructive apnea-hypopnea index (oAHI) ≥ 2 on polysomnography.

Results: This study included 130 obese patients (38% boys, mean age 12 years). Polysomnography results determined 44 patients (34%) with a diagnosis of OSA. Oximetry results classified 16 patients as positive, 43 as negative, and 71 as inconclusive. Further analysis of the positive and negative oximetry results showed a sensitivity and specificity of 58% and 88%, respectively, with a negative and positive predictive value of 81% and 69%, respectively. A second analysis, using the oxygen desaturation index, showed inferior results in comparison to the score attained by Brouillette (sensitivity 57%, specificity 73%).

Conclusions: These results suggest that oximetry alone is insufficient as a screening tool for OSA in obese children. Other screening methods need to be explored in the future.

Keywords: Adolescents; Children; Obesity; Obstructive Sleep apnea; Oximetry; Sleep-disordered breathing.