International Journal of COPD (Jan 2017)

Ectopic fat accumulation in patients with COPD: an ECLIPSE substudy

  • Martin M,
  • Almeras N,
  • Després JP,
  • Coxson HO,
  • Washko GR,
  • Vivodtzev I,
  • Wouters EFM,
  • Rutten E,
  • Williams MC,
  • Murchison JT,
  • MacNee W,
  • Sin DD,
  • Maltais F

Journal volume & issue
Vol. Volume 12
pp. 451 – 460

Abstract

Read online

Mickaël Martin,1 Natalie Almeras,1 Jean-Pierre Després,1 Harvey O Coxson,2 George R Washko,3 Isabelle Vivodtzev,4 Emiel FM Wouters,5 Erica Rutten,6 Michelle C Williams,7 John T Murchison,8 William MacNee,7 Don D Sin,2 François Maltais1 On behalf of the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE) Study Group 1Research Centre, Institut universitaire de cardiologie et de pneumologie de Québec, Université Laval, Québec, QC, 2Department of Radiology, University of British Columbia, Vancouver, BC, Canada; 3Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA; 4Hypoxia Pathophysiology Laboratory, Grenoble University Hospital, Grenoble, France; 5Department of Respiratory Medicine, Maastricht University Medical Center, Maastricht, 6Research and Development, CIRO, Horn, the Netherlands; 7Department of Respiratory Medicine, University of Edinburgh, 8Department of Radiology, Royal Infirmary of Edinburgh, Edinburgh, UK Background: Obesity is increasingly associated with COPD, but little is known about the prevalence of ectopic fat accumulation in COPD and whether this can possibly be associated with poor clinical outcomes and comorbidities. The Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE) substudy tested the hypothesis that COPD is associated with increased ectopic fat accumulation and that this would be associated with COPD-related outcomes and comorbidities.Methods: Computed tomography (CT) images of the thorax obtained in ECLIPSE were used to quantify ectopic fat accumulation at L2–L3 (eg, cross-sectional area [CSA] of visceral adipose tissue [VAT] and muscle tissue [MT] attenuation, a reflection of muscle fat infiltration) and CSA of MT. A dose–response relationship between CSA of VAT, MT attenuation and CSA of MT and COPD-related outcomes (6-minute walking distance [6MWD], exacerbation rate, quality of life, and forced expiratory volume in 1 second [FEV1] decline) was addressed with the Cochran–Armitage trend test. Regression models were used to investigate possible relationships between CT body composition indices and comorbidities.Results: From the entire ECLIPSE cohort, we identified 585 subjects with valid CT images at L2–L3 to assess body composition. CSA of VAT was increased (P<0.0001) and MT attenuation was reduced (indicating more muscle fat accumulation) in patients with COPD (P<0.002). Pro­gressively increasing CSA of VAT was not associated with adverse clinical outcomes. The probability of exhibiting low 6MWD and accelerated FEV1 decline increased with progressively decreasing MT attenuation and CSA of MT. In COPD, the probability of having diabetes (P=0.024) and gastroesophageal reflux (P=0.0048) at baseline increased in parallel with VAT accumulation, while the predicted MT attenuation increased the probability of cardiovascular comorbidities (P=0.042). Body composition parameters did not correlate with coronary artery scores or with survival.Conclusion: Ectopic fat accumulation is increased in COPD, and this was associated with relevant clinical outcomes and comorbidities. Keywords: metabolic syndrome, obesity, abdominal adiposity, muscle

Keywords