title: Waist-to-height ratio distinguish obstructive sleep apnea from primary snoring in obese children.
abstract: BACKGROUND
  Sleep-disordered breathing is caused by the interaction of multiple factors, including tonsillar hypertrophy, retrognathia, maxillary atresia, neuromuscular abnormalities, activation of inflammatory mediator cascades, and obesity. The prevalence and severity of obesity among children and adolescents increased worldwide during recent decades and has thus become a public health concern. The aim of this study is to assess the metabolic and anthropometric changes associated with sleep-disordered breathing in obese children.
  
  
  METHODS
  Prospective assessment of prepubertal obese children followed at a pediatric endocrinology outpatient clinic that had history of frequent snoring. Children were submitted to polysomnography, measurements of body weight, height, blood pressure, neck circumference, and waist circumference. BMI, neck-to-height, and waist-to-height ratios were calculated. Laboratory tests included a complete blood count, liver function tests, lipid profile, and glucose metabolism assessment. Additionally, the presence of metabolic syndrome was assessed. Differences between obstructive sleep apnea and primary snoring groups were calculated using unpaired t-test, Fisher's exact test or Mann-Whitney test (p < 0.05).
  
  
  RESULTS
  The sample included 20 children with primary snoring and nine with obstructive sleep apnea. The two groups did not differ with regard to age, gender, BMI, or BMI z-score, serum lipids, glucose metabolism, cell count, liver function, or arterial blood pressure. Anthropometric data did not differ between groups. The waist-to-height ratio was greater among children with obstructive sleep apnea, compared to those with primary snoring.
  
  
  CONCLUSIONS
  In the present study, the waist-to-height ratio was greater in children with obstructive sleep apnea and, thus, could distinguish these children from those with primary snoring.
authors.affiliation: Department of Otorhinolaryngology, Federal University of São Paulo, Rua Padre Luis dos Anjos, 256, Bairro Jundiaí, Anápolis, Goias, Brazil, CEP: 75110-520, jualves39@yahoo.com.br.
authors.forename: Juliana Alves
authors.initials: JA
authors.lastname: de Sousa Caixêta
authors.forename: Alex Martins
authors.initials: AM
authors.lastname: Saramago
authors.forename: Marcia Lourdes
authors.initials: ML
authors.lastname: de Cácia Pradella-Hallinan
authors.forename: Gustavo Antônio
authors.initials: GA
authors.lastname: Moreira
authors.forename: Sergio
authors.initials: S
authors.lastname: Tufik
authors.forename: Reginaldo Raimundo
authors.initials: RR
authors.lastname: Fujita
mesh_terms: D001938:Brazil; D002648:Child; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000175:diagnosis; D063766:Pediatric Obesity / Q000175:diagnosis*; D017286:Polysomnography; D011446:Prospective Studies; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis*; D012913:Snoring / Q000175:diagnosis*; D013223:Statistics as Topic; D065927:Waist-Height Ratio