title: Pulmonary artery pressure in chronic obstructive pulmonary disease without resting hypoxaemia.
abstract: BACKGROUND
  Chronic obstructive pulmonary disease (COPD) can lead to pulmonary hypertension and cor pulmonale, which are predictors of mortality.
  
  
  OBJECTIVE
  To identify predictors of increased pulmonary artery pressure (PAP) in COPD patients without resting hypoxaemia, and to characterise COPD patients with increased PAP.
  
  
  METHODS
  A study of 117 COPD patients from the Korean Obstructive Lung Disease (KOLD) cohort who had measurable tricuspid regurgitant flow under transthoracic Doppler echocardiography and no resting hypoxaemia.
  
  
  RESULTS
  The mean patient age was 67 years. Mean forced expiratory volume in 1 second (FEV(1)) was 47% predicted, mean haemoglobin (Hb) concentration was 145 g/l and mean systolic PAP (sPAP) was 33 mmHg. Multiple linear regression analysis showed that Hb was the only factor independently associated with sPAP (beta = -1.752, P = 0.005). Cluster analysis using FEV(1)% predicted, sPAP and Hb concentration as variables indicated three patient clusters: Cluster 1 (n = 36; mean FEV(1) 44% predicted, mean sPAP 39 mmHg, mean Hb 132 g/l), Cluster 2 (n = 45; FEV(1) 35% predicted, sPAP 31 mmHg, Hb 154 g/l), and Cluster 3 (n = 36; FEV(1) 65% predicted, sPAP 29 mmHg, Hb 148 g/l).
  
  
  CONCLUSIONS
  Elevated PAP was linked to low haemoglobin levels in COPD without resting hypoxaemia.
authors.affiliation: Department of Internal Medicine, Ewha Womans University School of Medicine, Ewha Medical Research Institute, Seoul, Republic of Korea.
authors.forename: J H
authors.initials: JH
authors.lastname: Lee
authors.forename: Y-M
authors.initials: YM
authors.lastname: Oh
authors.forename: J B
authors.initials: JB
authors.lastname: Seo
authors.forename: Y K
authors.initials: YK
authors.lastname: Lee
authors.forename: W J
authors.initials: WJ
authors.lastname: Kim
authors.forename: S S
authors.initials: SS
authors.lastname: Sheen
authors.forename: T-H
authors.initials: TH
authors.lastname: Kim
authors.forename: J-H
authors.initials: JH
authors.lastname: Lee
authors.forename: E-K
authors.initials: EK
authors.lastname: Kim
authors.forename: J S
authors.initials: JS
authors.lastname: Lee
authors.forename: J W
authors.initials: JW
authors.lastname: Huh
authors.forename: S Y
authors.initials: SY
authors.lastname: Lim
authors.forename: H I
authors.initials: HI
authors.lastname: Yoon
authors.forename: T R
authors.initials: TR
authors.lastname: Shin
authors.forename: S-M
authors.initials: SM
authors.lastname: Lee
authors.forename: S Y
authors.initials: SY
authors.lastname: Lee
authors.forename: S-D
authors.initials: SD
authors.lastname: Lee
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000740:Anemia / Q000150:complications*; D015331:Cohort Studies; D005260:Female; D005541:Forced Expiratory Volume; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D006976:Hypertension, Pulmonary / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology; D000860:Hypoxia; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D011651:Pulmonary Artery / Q000503:physiopathology*; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood* / Q000150:complications* / Q000503:physiopathology; D056910:Republic of Korea; D012307:Risk Factors; D013147:Spirometry; D011795:Surveys and Questionnaires
chemical_list: D006454:Hemoglobins