[Diagnostic utility of nocturnal in-home respiratory polygraphy]. / Rentabilidad de la poligrafía respiratoria del sueño realizada en el domicilio.

INTRODUCTION: Sleep apnea-hypopnea syndrome (SAHS) is relatively frequent in children. The gold standard for diagnosis is polysomnography. However, because of technical difficulties and the cost of this method, new alternatives have become available, such as respiratory polygraphy (RP) performed at home or in hospital, which have provided satisfactory results in children with clinical suspicion of SAHS. OBJECTIVE: The aim of this study was to analyze the diagnostic utility of in-home RP in the diagnosis of SAHS in a sample of boys and girls referred to the pediatric respiratory care department for suspected sleep apnea, snoring, or both. MATERIAL AND METHODS: In all patients, a history and physical examination were performed; X-ray of the chest and cavum and RP were carried out. The following qualitative variables were analyzed: place where RP was performed, the result, sex, the reason for consulting, place of residence, results of otorhinolaryngological examination, and treatment. The quantitative variables analyzed were age, total number of apneas, total number of hypopneas, apnea index/hour, hypopnea index/hour, mean and minimum SpxO2, number of snores per hour and the snore index/hour. Statistical analysis was performed using Pearson's chi-square test and Student's t-test. RESULTS: A total of 132 patients were studied, 44 (33.3 %) through in-home RP (group 1) and 88 (66.6 %) through in-hospital RP (group 2). In group 1, two recordings (4.5 %) were considered nonvalid. The mean age of the patients was 8.3 years (SD 3.02). The results [means (standard deviation)] of in-home RP were as follows: apnea-hypopnea index (AHI)/h: 3.4 (4.3); mean SpxO2: 97.3 (1.8); minimum SpxO2: 87.7 (10.3). In group 2, four recordings (4.5 %) were nonvalid. The mean age of the patients was 7.4 years (SD 3). The results of in-hospital RP were as follows: AHI/h: 4.45 (5.4); mean SpxO2: 96.8 (1.8); minimum SpxO2: 87 (11). No significant differences were found between the validity of in-home and in-hospital RP. Likewise, no significant differences were found between AHI/h, SpxO2 and in-home and in-hospital RP. CONCLUSION: In conclusion, in our sample, the diagnostic utility of in-home RP was equal to that of in-hospital RP. In-home RP allows the possibility of performing a more physiological sleep study and, by eliminating the cost of hospitalization, is more cost-efficient. Therefore, in-home RP is a valid and reliable technique for the diagnosis of childhood SAHS.