title: [Diagnostic value of respiratory polygraphy in patients with low probability of obstructive sleep apnea syndrome].
abstract: OBJECTIVE
  Polysomnography (PSG) is the gold standard technic for the diagnosis of obstructive sleep apnea syndrome (OSAS). It is an expensive, complex and not always available technic, meaning that respiratory polygraphy (RP) has become usual. Although RP is not validated in low probability patients, Spanish guidelines recommend conservative treatment in patients with negative RP. We intended to study the prevalence and severity of OSAS through PSG in a sample of patients with low probability and negative RP.
  
  
  METHODS
  Retrospective, observational, descriptive and analytic study of low probability OSAS patients with negative RP in whom a PSG was performed. Anthropometric, clinical and sleep data were collected.
  
  
  RESULTS
  Eighty-two patients were included. After PSG, a greater number of hypopneas (137.8±70.1 vs. 51.2±38.4 [P<.05]) and apnea hypopnea index (27.8±15.6 vs. 11.7±7.1 [P<.05]) was observed, as well as an increment in OSAS prevalence of 17%, which was 35% in severe OSAS. In mild OSAS, there was a decrement of 41%.
  
  
  CONCLUSIONS
  According with the results of this study, RP significantly underestimates the prevalence and severity of OSAS in low probability patients. While it is necessary to adequately stratify the OSAS probability in order to correctly indicate diagnosis tests, we recommend performing a PSG in low probability patients with negative RP.
authors.affiliation: Servicio de Neumología, Hospital Universitario Infanta Sofía, San Sebastián de los Reyes, Madrid, España. Electronic address: anahvoth@gmail.com.
authors.forename: Ana
authors.initials: A
authors.lastname: Hernandez Voth
authors.affiliation: Servicio de Neumología, Hospital Universitario Infanta Sofía, San Sebastián de los Reyes, Madrid, España.
authors.forename: Gemma
authors.initials: G
authors.lastname: Mora Ortega
authors.affiliation: Servicio de Neumología, Hospital Universitario Infanta Sofía, San Sebastián de los Reyes, Madrid, España.
authors.forename: Raul
authors.initials: R
authors.lastname: Moreno Zabaleta
authors.affiliation: Servicio de Neumología, Hospital Universitario Infanta Sofía, San Sebastián de los Reyes, Madrid, España.
authors.forename: Javier
authors.initials: J
authors.lastname: Montoro Zulueta
authors.affiliation: Servicio de Neumología, Hospital Universitario Infanta Sofía, San Sebastián de los Reyes, Madrid, España.
authors.forename: Maria I
authors.initials: MI
authors.lastname: Verdugo Cartas
authors.affiliation: Servicio de Neumología, Hospital Universitario Infanta Sofía, San Sebastián de los Reyes, Madrid, España.
authors.forename: Blas
authors.initials: B
authors.lastname: Rojo Moreno-Arrones
authors.affiliation: Servicio de Neumología, Hospital Universitario Infanta Sofía, San Sebastián de los Reyes, Madrid, España.
authors.forename: Vanesa
authors.initials: V
authors.lastname: Lores Gutierrez
authors.affiliation: Servicio de Neumología, Hospital Universitario Infanta Sofía, San Sebastián de los Reyes, Madrid, España.
authors.forename: María T
authors.initials: MT
authors.lastname: Ramirez Prieto
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017286:Polysomnography; D015995:Prevalence; D012189:Retrospective Studies; D012306:Risk; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis* / Q000453:epidemiology; D013030:Spain / Q000453:epidemiology
keywords: Baja probabilidad; Low probability; Obstructive sleep apnea syndrome; Poligrafía; Polisomnografía; Polygraphy; Polysomnography; Síndrome de apneas obstructivas de sueño