title: Co-morbidities and sleep apnoea severity. A study in a cohort of Portuguese patients.
abstract: BACKGROUND
  Obstructive sleep apnoea syndrome (OSAS) is frequently associated to other morbid conditions that act as risk factors influencing OSAS morbidity and mortality.
  
  
  OBJECTIVE
  To analyse the presence of co-morbidities in OSAS patients, recruited from a sleep outpatient clinic in Northern Portugal, stratified as a function of OSAS severity.
  
  
  METHODS
  A cohort of 319 sleep-disordered patients was assessed by clinical and sleep video-polygraphic recording. Patients (n = 209) with sleep respiratory distress had OSAS (n = 145) and severity defined according to Apnoea/Hypopnea Index (AHI); 64 had primary snoring or respiratory distress with AHI < 5; and 110 had other sleep disorders. A full individual background study was possible in 128 OSAS patients. The association to unique or multiple co-morbidities was assessed by clinical and analytical studies in general group or as a function of OSAS severity.
  
  
  RESULTS
  The presence of co-morbidities was of 75% in all OSAS patients and of 79.5% in the severe group of OSAS. Forty seven of patients had only one co-morbidity. The most common was obesity (56.3%) followed by high blood pressure, diabetes and other cardiovascular disorders. Obesity was present in 84% among the most severe OSAS cases and always present in those with multiple co-morbidities. When compared with the group of patients without sleep respiratory distress the co-morbidity condition was more frequently related to OSAS (p = 0.0196).
  
  
  CONCLUSIONS
  Comorbidities are commonly associated to OSAS independently of disease severity. Among the comorbidities present obesity was the most common in the most severe OSAS cases.
authors.affiliation: CESPU, Gandra - Paredes, Portugal.
authors.forename: L
authors.initials: L
authors.lastname: Silva
authors.affiliation: Hospital de Santo Antonio, Porto, Portugal.
authors.forename: D
authors.initials: D
authors.lastname: Cunha
authors.affiliation: Hospital de Santo Antonio, Porto, Portugal.
authors.forename: J
authors.initials: J
authors.lastname: Lopes
authors.affiliation: Hospital de Santo Antonio, Porto, Portugal.
authors.forename: J
authors.initials: J
authors.lastname: Ramalheira
authors.affiliation: Universidad de Santiago de Compostela, Santiago de Compostela, Espana.
authors.forename: M
authors.initials: M
authors.lastname: Freire
authors.affiliation: Universidad de Santiago de Compostela, Santiago de Compostela, Espana.
authors.forename: S
authors.initials: S
authors.lastname: Novio
authors.affiliation: Universidad de Santiago de Compostela, Santiago de Compostela, Espana.
authors.forename: M J
authors.initials: MJ
authors.lastname: Nunez
authors.affiliation: Universidade do Porto, Porto, Portugal.
authors.forename: D
authors.initials: D
authors.lastname: Mendonca
authors.affiliation: Universidade do Porto, Porto, Portugal.|Hospital de Santo Antonio/Centro Hospitalar do Porto, Porto, Portugal.
authors.forename: A
authors.initials: A
authors.lastname: Martins-da-Silva
mesh_terms: D015331:Cohort Studies; D015897:Comorbidity; D006801:Humans; D011174:Portugal / Q000453:epidemiology; D012891:Sleep Apnea Syndromes / Q000453:epidemiology*; D020181:Sleep Apnea, Obstructive / Q000453:epidemiology*