title: Association between Obstructive Sleep Apnea and Community-Acquired Pneumonia.
abstract: BACKGROUND
  We hypothesized that obstructive sleep apnea (OSA) can predispose individuals to lower airway infections and community-acquired pneumonia (CAP) due to upper airway microaspiration. This study evaluated the association between OSA and CAP.
  
  
  METHODS
  We performed a case-control study that included 82 patients with CAP and 41 patients with other infections (control group). The controls were matched according to age, sex and body mass index (BMI). A respiratory polygraph (RP) was performed upon admission for patients in both groups. The severity of pneumonia was assessed according to the Pneumonia Severity Index (PSI). The associations between CAP and the Epworth Sleepiness Scale (ESS), OSA, OSA severity and other sleep-related variables were evaluated using logistic regression models. The associations between OSA, OSA severity with CAP severity were evaluated with linear regression models and non-parametric tests.
  
  
  RESULTS
  No significant differences were found between CAP and control patients regarding anthropometric variables, toxic habits and risk factors for CAP. Patients with OSA, defined as individuals with an Apnea-Hypopnea Index (AHI) ≥10, showed an increased risk of CAP (OR = 2·86, 95%CI 1·29-6·44, p = 0·01). Patients with severe OSA (AHI≥30) also had a higher risk of CAP (OR = 3·18, 95%CI 1·11-11·56, p = 0·047). In addition, OSA severity, defined according to the AHI quartile, was also significantly associated with CAP (p = 0·007). Furthermore, OSA was significantly associated with CAP severity (p = 0·0002), and OSA severity was also associated with CAP severity (p = 0·0006).
  
  
  CONCLUSIONS
  OSA and OSA severity are associated with CAP when compared to patients admitted to the hospital for non-respiratory infections. In addition, OSA and OSA severity are associated with CAP severity. These results support the potential role of OSA in the pathogenesis of CAP and could have clinical implications. This link between OSA and infection risk should be explored to investigate the relationships among gastroesophageal reflux, silent aspiration, laryngeal sensory dysfunction and CAP.
  
  
  BACKGROUND
  ClinicalTrials.gov NCT01071421.
authors.affiliation: Respiratory Department, Hospital Universitari Sant Joan d'Alacant, Alacant, Spain.
authors.forename: Eusebi
authors.initials: E
authors.lastname: Chiner
authors.affiliation: Respiratory Department, Hospital Universitari Sant Joan d'Alacant, Alacant, Spain.
authors.forename: Mónica
authors.initials: M
authors.lastname: Llombart
authors.affiliation: Biostatistics and Epidemiology Unit, IRB Lleida, Catalonia, Spain.
authors.forename: Joan
authors.initials: J
authors.lastname: Valls
authors.affiliation: Respiratory Department, Hospital Universitari Sant Joan d'Alacant, Alacant, Spain.
authors.forename: Esther
authors.initials: E
authors.lastname: Pastor
authors.affiliation: Respiratory Department, Hospital Universitari Sant Joan d'Alacant, Alacant, Spain.
authors.forename: José N
authors.initials: JN
authors.lastname: Sancho-Chust
authors.affiliation: Respiratory Department, Hospital Universitari Sant Joan d'Alacant, Alacant, Spain.
authors.forename: Ada Luz
authors.initials: AL
authors.lastname: Andreu
authors.affiliation: Respiratory Department, Hospital Universitari Arnau de Vilanova and Santa Maria, Universitat de Lleida, IRB Lleida, Catalonia, Spain.|Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Sánchez-de-la-Torre
authors.affiliation: Respiratory Department, Hospital Universitari Arnau de Vilanova and Santa Maria, Universitat de Lleida, IRB Lleida, Catalonia, Spain.|Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain.
authors.forename: Ferran
authors.initials: F
authors.lastname: Barbé
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D017714:Community-Acquired Infections / Q000150:complications*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011014:Pneumonia / Q000150:complications*; D020181:Sleep Apnea, Obstructive / Q000150:complications*; D055815:Young Adult