Ambulatory blood pressure before and after adenotonsillectomy in children with obstructive sleep apnea.

INTRODUCTION: Hypertension is found to be associated with obstructive sleep apnea (OSA) in both children and adults. But data on the effect of blood pressure after adenotonsillectomy (AT) for children with OSA are limited and controversial. OBJECTIVE: To assess the impact of AT on different parameters of 24-h ambulatory blood pressure monitoring in children with OSA. METHODS: We retrospectively reviewed records of OSA children who had undergone AT and a repeated sleep polysomnography after AT from 2001 to 2008. RESULTS: Forty-four children were identified and included in the analysis. The mean apnea-hypopnea index (AHI) dropped from 14.14+/-15.9 to 3.3+/-7.1. (p<0.001). Twenty (45%) were cured of OSA. After AT, the diastolic BP load decreased significantly. Six out of eight (75%) hypertensive children became normotensive after surgery. For the pre-AT hypertensive group, both systolic and diastolic blood pressure decreased significantly during sleep after AT. However, eight children who were normotensive before AT became hypertensive after AT. These 10 post-AT hypertensive patients were more likely to have post-AT AHI>1 than the post-AT normotensive group, although the difference did not reach statistical significance. CONCLUSION: In the current cohort of OSA children, 44% were cured of OSA and a significant decrease in overall diastolic blood pressure load in 24-h ambulatory blood pressure was achieved after adenotonsillectomy for children with OSA. But hypertension may persist or even occur in those previously normotensive children despite the improvement in AHI. Persistence of OSA may be a risk factor and further study is required. Cure of OSA should not be assumed after AT and follow-up PSG should be performed together with 24-h ambulatory blood pressure monitoring. In light of the current findings, long term study of the blood pressure is warranted for children with OSA.

Application of videotape in the screening of obstructive sleep apnea in children.

OBJECTIVE: To determine if watching a videotape that shows features of obstructive sleep apnea (OSA) will improve the accuracy of a verbally administered questionnaire in the prediction of OSA in pediatric snorers. PATIENTS AND METHODS: In a prospective single-blinded, randomized, controlled study at a pediatric clinic for sleep-disordered breathing, we studied children aged 0-18 years, who had been referred to a sleep laboratory for overnight polysomnography (PSG), and their parents from November 1999 to November 2000. The parents were randomized to answer a standard verbally administered panel of three questions (SQ) or a verbally administered panel of questions assisted by videotape (VQ). RESULTS: The parents of 52 and 56 pediatric snorers were assigned to answer SQ and VQ, respectively. The areas under the receiver operating characteristic [ROC] curves (AUCs) for screening of OSA in patients were similar at 0.709 (95% confidence interval (CI)=0.561-0.851) for SQ and 0.714 (95% CI=0.571-0.858) for VQ. The two questionnaires had a reasonable negative predictive value to rule out the presence of OSA (VQ=0.816 and 95% CI=0.726-0.885, SQ=0.828, 95% CI=0.714-0.913). CONCLUSION: The addition of a videotape showing important features of OSA achieved no better accuracy than a standard questionnaire.

The correlation among obesity, apnea-hypopnea index, and tonsil size in children.

BACKGROUND: The correlation between obesity and severity of obstructive sleep apnea (OSA) is well established in adults, but data are inconsistent in children. We hypothesized that there is a significant correlation between the degree of obesity and the severity of OSA in children. METHODS: We retrospectively reviewed records of weight, height, history, and polysomnography of all 1- to 15- year-old children referred to our sleep laboratory. Children with known anomalies and repeated polysomnography were excluded from this study. Obesity was defined as body mass index z score (BMI Z score) > 1.96. The correlation between BMI Z score and apnea-hypopnea index (AHI) was assessed. Possible confounding factors, ie, age, gender, and tonsil size, were adjusted by multiple linear regression. RESULTS: Four hundred eighty-two children were included in this study. Obese children had a significantly higher AHI (median, 1.5; interquartile range [IQR], 0.2 to 7.0) than the AHI of nonobese children (median, 0.7; IQR, 0.0 to 2.5). BMI Z score was significantly correlated with log-transformed AHI (Ln[AHI]) [r = 0.156, p = 0.003]. BMI Z score and tonsil size were still correlated with Ln(AHI) even after adjusted for other confounding factors (p = 0.001). CONCLUSION: Degree of obesity as measured by BMI Z score and tonsil size are significantly related to severity of OSA as reflected by the AHI, although the correlation is mild.