title: Functional capacity, health status, and inflammatory biomarker profile in a cohort of patients with chronic obstructive pulmonary disease.
abstract: OBJECTIVE
  Prior research has shown a significant relationship between 6-minute walking distance (6MWD) and health-related quality of life (HRQOL) in patients with chronic obstructive pulmonary disease (COPD). However, few studies have examined this relationship above and below the 350-m threshold that prognosticates survival and whether serum biomarkers could provide insight into the causes of quality-of-life differences above and below this threshold.
  
  
  METHODS
  Measures of lung function, 6MWD, and HRQOL were compared in patients with COPD. Differences in HRQOL domains and serum biomarkers were compared in patients whose 6MWD were > or < 350 m.
  
  
  RESULTS
  In patients walking < 350 m, scores in the physical domains of the SF-36 and the St. George's Respiratory Questionnaire (SGRQ) were significantly different from scores of their counterparts with greater 6MWD. However, there was no association between any biomarkers and the physical domains of the SF-36 and the SGRQ. In patients walking < 350 m, only the IL-8 levels were associated with lower scores in SF-36 domains of emotional role, pain, vitality, and mental health (average r = -0.702; P = .01). In contrast, in patients walking > 350 m, surfactant protein D levels were associated with higher SF-36 scores in general pain, vitality, and social functioning (average r = 0.42; P = .04).
  
  
  CONCLUSIONS
  In COPD, there is an association between 6MWD and the physical domains of the SF-36 and SGRQ in those patients walking < 350 m. The physical differences between patients walking < or > 350 m are not related to systemic inflammation. The association between interleukin 8 with nonphysical domains in patients with 6MWD < 350 m suggests that inflammation may play a larger role in the perceptive domain than previously recognized.
authors: Division of Pulmonary and Critical Care Medicine, Brigham & Women's Hospital, Harvard Medical School, Boston, Massachusetts (Drs Kohli, Pinto-Plata, Divo, and Celli); Division of Pulmonary and Critical Care Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts (Drs Kohli and Harris); Division of Pulmonary and Critical Care Medicine, Division of Sleep Medicine, University of California San Diego School of Medicine, San Diego, California (Dr Malhotra); COPD Clinical Discovery, GalaxoSmithKline, King of Prussia, Pennsylvania (Drs Lazaar, Flynn, and Tal-Singer); and Division of Pulmonary, Allergy and Critical Care, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania (Dr Panettieri).
authors: Puja
authors: P
authors: Kohli
authors: Victor
authors: V
authors: Pinto-Plata
authors: Miguel
authors: M
authors: Divo
authors: Atul
authors: A
authors: Malhotra
authors: R Scott
authors: RS
authors: Harris
authors: Aili
authors: A
authors: Lazaar
authors: Aiden
authors: A
authors: Flynn
authors: Ruth
authors: R
authors: Tal-Singer
authors: Reynold A
authors: RA
authors: Panettieri
authors: Bartolome
authors: B
authors: Celli
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D015415:Biomarkers / Q000097:blood; D015331:Cohort Studies; D005080:Exercise Test / Q000706:statistics & numerical data*; D005260:Female; D006304:Health Status; D006801:Humans; D007249:Inflammation / Q000097:blood*; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood* / Q000503:physiopathology*; D011788:Quality of Life; D011795:Surveys and Questionnaires; D016138:Walking
chemical_list: D015415:Biomarkers