title: Factors related to variability in long-term oxygen therapy prevalence.
abstract: OBJECTIVE
  To analyse the variability of long term oxygen therapy (LTOT) prevalence according to several organisational and population factors.
  
  
  METHODS
  Prospective multicentre survey in 29 public hospitals (population 6,796,964) recording data on the organisational structure of the participating centres and factors related to LTOT prevalence. Official figures were also obtained from local health authorities on the prevalence and cost of LTOT.
  
  
  RESULTS
  The overall prevalence of LTOT was 184 per 100000 population (range 71-473). There was a specific unit or staff member for LTOT supervision in 17 (58.6%) centres, giving a lower prevalence (169 vs. 237/ 100000; P = 0.03). The altitude of the participating centres (median 92 m, mean 275 m; range 4-848 m) was found to influence LTOT prevalence (r = 0.73; P = 0.005). In the linear regression analysis, the coefficient of determination for altitude was 0.504. Other factors, such as percentage of population aged over 65 years, the attitude of prescribers towards patients with low adherence, current smokers or those with a PaO2 = 61 mmHg, were not related to LTOT prevalence.
  
  
  CONCLUSIONS
  Altitude and the existence of a specific unit or staff member for LTOT supervision significantly influence LTOT prevalence.
authors.affiliation: Puerta del Mar University Hospital, Cádiz, Spain. antonio.leon@separ.es
authors.forename: A León
authors.initials: AL
authors.lastname: Jiménez
authors.forename: J L
authors.initials: JL
authors.lastname: López-Campos
authors.forename: F
authors.initials: F
authors.lastname: Casas
authors.forename: B
authors.initials: B
authors.lastname: Jurado
authors.forename: S
authors.initials: S
authors.lastname: Cano
authors.forename: A
authors.initials: A
authors.lastname: Arnedillo
authors.forename: L
authors.initials: L
authors.lastname: Muñoz
authors.forename: S
authors.initials: S
authors.lastname: López
mesh_terms: D000368:Aged; D000531:Altitude; D019538:Health Care Surveys; D006779:Hospitals, Public; D006801:Humans; D010102:Oxygen Inhalation Therapy / Q000295:instrumentation / Q000706:statistics & numerical data*; D010349:Patient Compliance; D055656:Prescriptions; D029424:Pulmonary Disease, Chronic Obstructive / Q000453:epidemiology / Q000628:therapy*; D012907:Smoking; D013030:Spain / Q000453:epidemiology