Polysomnography is the best tool available for diagnosing obstructive sleep apnea (OSA) in children. However, polysomnography is relatively inaccessible and costly, and studies are needed to evaluate other diagnostic approaches. It has been suggested that the OSA-18 quality-of-life questionnaire (OSA-18) is a useful measure that could replace polysomnography. The purpose of our study was to determine if the OSA-18, is an accurate measure for the detection of moderate-to-severe OSA.
Children who were referred to our sleep laboratory for evaluation of suspected OSA and who had a nocturnal pulse oximetry study were included in our cross-sectional study. The results of the oximetry study were interpreted by using the McGill oximetry score (MOS). Abnormal scores were consistent with moderate-to-severe OSA. We analyzed demographic and medical data in addition to the OSA-18 results. We estimated sensitivity and negative predictive values for the OSA-18 to detect an abnormal MOS. We also conducted logistic regression analyses with MOS as the dependent variable and the OSA-18 score, age, gender, comorbidities, and race as independent variables.
We studied 334 children (mean age: 4.6 years; 58% male). The OSA-18 had a sensitivity of 40% and a negative predictive value of 73% for detecting an abnormal MOS. While controlling for other variables in the regression model, for each unit increase in the OSA-18 score, the odds of having an abnormal MOS were increased by 2%. For each 1-year increase in age, the odds of having an abnormal MOS were decreased by 17%.
Among children who are referred to a sleep laboratory, the OSA-18 does not accurately detect which children will have an abnormal MOS and cannot be used to exclude moderate-to-severe OSA. The OSA-18 should not be used in the place of objective testing to identify moderate-to-severe OSA in children.