title: Comorbidities of COPD have a major impact on clinical outcomes, particularly in African Americans.
abstract: BACKGROUND
  COPD patients have a great burden of comorbidity. However, it is not well established whether this is due to shared risk factors such as smoking, if they impact patients exercise capacity and quality of life, or whether there are racial disparities in their impact on COPD.
  
  
  METHODS
  We analyzed data from 10,192 current and ex-smokers with (cases) and without COPD (controls) from the COPDGene®cohort to establish risk for COPD comorbidities adjusted for pertinent covariates. In adjusted models, we examined comorbidities prevalence and impact in African-Americans (AA) and Non-Hispanic Whites (NHW).
  
  
  RESULTS
  Comorbidities are more common in COPD compared to those with normal spirometry (controls), and the risk persists after adjustments for covariates including pack-years smoked. After adjustment for confounders, eight conditions were independently associated with worse exercise capacity, quality of life and dyspnea. There were racial disparities in the impact of comorbidities on exercise capacity, dyspnea and quality of life, presence of osteoarthritis and gastroesophageal reflux disease having a greater negative impact on all three outcomes in AAs than NHWs (p<0.05 for all interaction terms).
  
  
  CONCLUSIONS
  Individuals with COPD have a higher risk for comorbidities than controls, an important finding shown for the first time comprehensively after accounting for confounders. Individual comorbidities are associated with worse exercise capacity, quality of life, and dyspnea, in African-Americans compared to non-Hispanic Whites.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland, USA.
authors.forename: Nirupama
authors.initials: N
authors.lastname: Putcha
authors.affiliation: Division of Pulmonary and Critical Care Medicine, University of Michigan, Ann Arbor, Michigan, USA.
authors.forename: Meilan K
authors.initials: MK
authors.lastname: Han
authors.affiliation: Division of Pulmonary and Critical Care Medicine, University of Michigan, Ann Arbor, Michigan, USA.
authors.forename: Carlos H
authors.initials: CH
authors.lastname: Martinez
authors.affiliation: Divison of Pulmonary and Critical Care Medicine, Morehouse School of Medicine, Atlanta, GA, USA.
authors.forename: Marilyn G
authors.initials: MG
authors.lastname: Foreman
authors.affiliation: Pulmonary Section, Department of Medicine, University of Texas Health Science Center, and South Texas Veterans Health Care System, San Antonio, TX, USA.
authors.forename: Antonio R
authors.initials: AR
authors.lastname: Anzueto
authors.affiliation: Rehabilitation Clinical Trials Center, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, California, USA.
authors.forename: Richard
authors.initials: R
authors.lastname: Casaburi
authors.affiliation: Channing Division of Network Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Michael H
authors.initials: MH
authors.lastname: Cho
authors.affiliation: Section of Pulmonary, Critical Care and Sleep Medicine, Baylor College of Medicine, Houston, Texas, USA.
authors.forename: Nicola A
authors.initials: NA
authors.lastname: Hanania
authors.affiliation: Channing Division of Network Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Craig P
authors.initials: CP
authors.lastname: Hersh
authors.affiliation: Colorado School of Public Health, Aurora, Colorado, USA.
authors.forename: Gregory L
authors.initials: GL
authors.lastname: Kinney
authors.affiliation: Division of Pulmonary, Critical Care and Sleep Medicine, National Jewish Health, Denver, Colorado, USA.
authors.forename: Barry J
authors.initials: BJ
authors.lastname: Make
authors.affiliation: Department of Radiology, Temple University School of Medicine, Philadelphia, Pennsylvania, USA.
authors.forename: Robert M
authors.initials: RM
authors.lastname: Steiner
authors.affiliation: Colorado School of Public Health, Aurora, Colorado, USA.
authors.forename: Sharon M
authors.initials: SM
authors.lastname: Lutz
authors.affiliation: Division of Pulmonary, Allergy and Critical Care Medicine, Columbia University, New York, New York, USA.
authors.forename: Byron M
authors.initials: BM
authors.lastname: Thomashow
authors.affiliation: Division of Biostatistics and Bioinformatics, National Jewish Health, Denver, Colorado, USA.
authors.forename: Andre A
authors.initials: AA
authors.lastname: Williams
authors.affiliation: Division of Pulmonary, Allergy and Critical Care Medicine, University of Alabama Birmingham, Birmingham, Alabama, USA.
authors.forename: Surya P
authors.initials: SP
authors.lastname: Bhatt
authors.affiliation: Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
authors.forename: Terri H
authors.initials: TH
authors.lastname: Beaty
authors.affiliation: Division of Pulmonary, Critical Care and Sleep Medicine, National Jewish Health, Denver, Colorado, USA.
authors.forename: Russell P
authors.initials: RP
authors.lastname: Bowler
authors.affiliation: Department of Medicine, University of California San Diego, San Diego, CA, USA.
authors.forename: Joe W
authors.initials: JW
authors.lastname: Ramsdell
authors.affiliation: Division of Pulmonary and Critical Care Medicine, University of Michigan, Ann Arbor, Michigan, USA.
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Curtis
authors.affiliation: Division of Biostatistics and Bioinformatics, National Jewish Health, Denver, Colorado, USA.
authors.forename: Douglas
authors.initials: D
authors.lastname: Everett
authors.affiliation: Colorado School of Public Health, Aurora, Colorado, USA.
authors.forename: John E
authors.initials: JE
authors.lastname: Hokanson
authors.affiliation: Division of Radiology, National Jewish Health, Denver, Colorado, USA.
authors.forename: David A
authors.initials: DA
authors.lastname: Lynch
authors.affiliation: Division of Pulmonary, Critical Care and Sleep Medicine, National Jewish Health, Denver, Colorado, USA.
authors.forename: E Rand
authors.initials: ER
authors.lastname: Sutherland
authors.affiliation: Channing Division of Network Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Edwin K
authors.initials: EK
authors.lastname: Silverman
authors.affiliation: Division of Pulmonary, Critical Care and Sleep Medicine, National Jewish Health, Denver, Colorado, USA.
authors.forename: James D
authors.initials: JD
authors.lastname: Crapo
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland, USA.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Wise
authors.affiliation: Department of Medicine, National Jewish Health, Denver, Colorado, USA.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Regan
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland, USA.
authors.forename: Nadia N
authors.initials: NN
authors.lastname: Hansel
keywords: COPD; Comorbidities; Race