title: BMI and oral glucocorticoids as predictors of prognosis in COPD patients on long-term oxygen therapy.
abstract: OBJECTIVE
  The objectives of the study were to determine whether body mass index (BMI), and oral corticosteroid use predict survival and hospitalization in hypoxaemic chronic obstructive pulmonary disease (COPD) patients.
  
  
  METHODS
  The study was a prospective cohort study with analysis of a nationwide database (Danish Oxygen Register). We studied survival and hospitalization in 221 hypoxaemic COPD patients who were on long-term oxygen therapy (LTOT).
  
  
  RESULTS
  Low BMI was strongly associated with high mortality (P < 0.001). Maintenance treatment with steroids was only associated with higher mortality in overweight patients (BMI > or = 25 kg/m2), RR = 3.8 (1.4-10.5), P = 0.011. Whereas BMI had no influence on risk of any hospitalization in patients using oral steroids, high BMI was independently associated with reduced risk of any hospitalization in patients without oral steroids [the RR of any hospitalization for each 1 kg/m2 increase in BMI was 0.94 (CI: 0.90-0.99), P = 0.009]. Overall, the use of oral steroids was associated with increased risk of any hospitalization, RR = 1.7 (1.2-2.4), P = 0.002. This increase was especially pronounced in the group with BMI above 25 kg/m2, where steroid treatment increased the risk of any hospitalization with RR = 3.6 (1.5-8.7), P = 0.005.
  
  
  CONCLUSIONS
  In hypoxaemic patients on LTOT, low BMI is an independent risk factor of death and any hospitalization. Maintenance treatment with oral corticosteroids is associated with increased mortality and hospitalization in COPD patients with high BMI. Our findings suggest that loss of body weight should be avoided, and that oral corticosteroids should be used cautiously in patients on LTOT--especially those with high BMI. Further research on the role of changes in body composition as a prognostic factor is needed.
authors.affiliation: Department of Respiratory Medicine, University Hospital of Copenhagen, Hvidovre, Denmark. ringbaek@dadlnet.dk
authors.forename: T J
authors.initials: TJ
authors.lastname: Ringbaek
authors.forename: K
authors.initials: K
authors.lastname: Viskum
authors.forename: P
authors.initials: P
authors.lastname: Lange
mesh_terms: D000284:Administration, Oral; D000368:Aged; D000818:Animals; D001823:Body Composition; D015992:Body Mass Index; D015331:Cohort Studies; D005938:Glucocorticoids / Q000008:administration & dosage*; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008134:Long-Term Care; D008297:Male; D010102:Oxygen Inhalation Therapy; D011379:Prognosis; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000401:mortality* / Q000628:therapy*
chemical_list: D005938:Glucocorticoids