[Reliability of respiratory polygraphy for the diagnosis of sleep apnea-hypopnea syndrome in children]

Objective Overnight polysomnography (PSG) is thegold standard diagnostic tool for sleep apnea-hypopneasyndrome (SAHS) in children. The aim of the present studywas to evaluate the usefulness of diagnostic respiratorypolygraphy in children with clinically suspected SAHSreferred to our sleep-disordered breathing clinic. Patients and Methods We studied 53 children referredwith clinical suspicion of SAHS; 29 (54.7%) were boys andthe mean (SD) age was 6.4 (2.9) years. After a medicalhistory was taken and a physical examination performed, patients underwent respiratory polygraphy (Edentec)simultaneously with overnight PSG in the sleep laboratory. The 2 diagnostic tools were compared using statisticalanalysis. Results SAHS was defined by an obstructive apnea-hypopnea index (OAHI) of 3 or more in overnight PSG anda respiratory disturbance index (RDI) of 3 or more inrespiratory polygraphy. The rate of diagnostic agreementwas 84.9%. The difference between the mean OAHI andRDI values was not significant (0.7 [5.4]; P =.34). Theintraclass correlation coefficient between the OAHI andRDI was 89.4 (95% confidence interval, 82.4-93.7; P When receiver operating characteristic curves werecalculated for the OAHI cutoff points used for the diagnosisof SAHS (1, 3, and 5), the best RDI cutoff for all 3 OAHI valuesconsidered was found to be 4.6. When age strata wereconsidered, in children 6 years or older the best RDI cutofffor the 3 OAHI values was 2.1. In children younger than 6 years the best RDI cutoff was 3.35 for OAHI 1 and 5.85 forOAHI 3 and 5. Conclusions Respiratory polygraphy in the sleeplaboratory is a valid method for the diagnosis of SAHS inchildren.