title: Paucity of evidence for a relationship between long-chain omega-3 fatty acid intake and chronic obstructive pulmonary disease: a systematic review.
abstract: BACKGROUND
  The anti-inflammatory activity of long-chain n-3 polyunsaturated fatty acids (PUFAs) has been established in several chronic inflammatory diseases but has yet to be demonstrated in inflammatory lung diseases such as chronic obstructive pulmonary disease (COPD).
  
  
  OBJECTIVE
  The aim of this systematic review was to investigate, using PRISMA guidelines, the relationship between the intake of long-chain n-3 PUFAs and the prevalence, severity, and health outcomes of COPD.
  
  
  METHODS
  Eight health databases and the World Health Organization's international clinical trial registry were searched for relevant studies.
  
  
  METHODS
  Experimental or observational studies that were published in English and that assessed long-chain n-3 PUFA intake (by determining habitual consumption and/or tissue levels) in adults with COPD were included.
  
  
  METHODS
  Publication demographics, participant characteristics, type of intervention or exposure, long-chain n-3 PUFA intake, pulmonary function, COPD mortality, and COPD severity were independently extracted from each article by 2 authors using a prospectively designed data extraction tool.
  
  
  RESULTS
  All 11 of the studies included in the review were observational. Approximately equal numbers of studies reported significant (n = 6, 5 inverse) relationships or no significant relationships (n = 5) between either consumption of long-chain n-3 PUFAs or levels of long-chain n-3 PUFAS in tissue and a COPD outcome.
  
  
  CONCLUSIONS
  Current evidence of a relationship between long-chain n-3 PUFA intake and COPD is limited and conflicting, with studies having wide methodological variation.
  
  
  BACKGROUND
  PROSPERO 2013:CRD42013004085.
authors.affiliation: A.S. Fulton and A.M. Coates are with the School of Health Sciences, University of South Australia, Adelaide, South Australia, Australia. M.T. Williams is with the School of Population Health, University of South Australia, Adelaide, South Australia, Australia. P.R.C. Howe is with the Clinical Nutrition Research Centre, School of Biomedical Sciences & Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia. A.M. Hill is with the School of Pharmacy & Medical Sciences, University of South Australia, Adelaide, South Australia, Australia. A.S. Fulton, A.M. Hill, M.T. Williams, P.R.C. Howe, and A.M. Coates are with the Alliance for Research in Exercise, Nutrition and Activity (ARENA), Sansom Institute for Health Research, Division of Health Sciences, University of South Australia, Adelaide, South Australia, Australia.
authors.forename: Ashley S
authors.initials: AS
authors.lastname: Fulton
authors.affiliation: A.S. Fulton and A.M. Coates are with the School of Health Sciences, University of South Australia, Adelaide, South Australia, Australia. M.T. Williams is with the School of Population Health, University of South Australia, Adelaide, South Australia, Australia. P.R.C. Howe is with the Clinical Nutrition Research Centre, School of Biomedical Sciences & Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia. A.M. Hill is with the School of Pharmacy & Medical Sciences, University of South Australia, Adelaide, South Australia, Australia. A.S. Fulton, A.M. Hill, M.T. Williams, P.R.C. Howe, and A.M. Coates are with the Alliance for Research in Exercise, Nutrition and Activity (ARENA), Sansom Institute for Health Research, Division of Health Sciences, University of South Australia, Adelaide, South Australia, Australia.
authors.forename: Alison M
authors.initials: AM
authors.lastname: Hill
authors.affiliation: A.S. Fulton and A.M. Coates are with the School of Health Sciences, University of South Australia, Adelaide, South Australia, Australia. M.T. Williams is with the School of Population Health, University of South Australia, Adelaide, South Australia, Australia. P.R.C. Howe is with the Clinical Nutrition Research Centre, School of Biomedical Sciences & Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia. A.M. Hill is with the School of Pharmacy & Medical Sciences, University of South Australia, Adelaide, South Australia, Australia. A.S. Fulton, A.M. Hill, M.T. Williams, P.R.C. Howe, and A.M. Coates are with the Alliance for Research in Exercise, Nutrition and Activity (ARENA), Sansom Institute for Health Research, Division of Health Sciences, University of South Australia, Adelaide, South Australia, Australia.
authors.forename: Marie T
authors.initials: MT
authors.lastname: Williams
authors.affiliation: A.S. Fulton and A.M. Coates are with the School of Health Sciences, University of South Australia, Adelaide, South Australia, Australia. M.T. Williams is with the School of Population Health, University of South Australia, Adelaide, South Australia, Australia. P.R.C. Howe is with the Clinical Nutrition Research Centre, School of Biomedical Sciences & Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia. A.M. Hill is with the School of Pharmacy & Medical Sciences, University of South Australia, Adelaide, South Australia, Australia. A.S. Fulton, A.M. Hill, M.T. Williams, P.R.C. Howe, and A.M. Coates are with the Alliance for Research in Exercise, Nutrition and Activity (ARENA), Sansom Institute for Health Research, Division of Health Sciences, University of South Australia, Adelaide, South Australia, Australia.
authors.forename: Peter R C
authors.initials: PR
authors.lastname: Howe
authors.affiliation: A.S. Fulton and A.M. Coates are with the School of Health Sciences, University of South Australia, Adelaide, South Australia, Australia. M.T. Williams is with the School of Population Health, University of South Australia, Adelaide, South Australia, Australia. P.R.C. Howe is with the Clinical Nutrition Research Centre, School of Biomedical Sciences & Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia. A.M. Hill is with the School of Pharmacy & Medical Sciences, University of South Australia, Adelaide, South Australia, Australia. A.S. Fulton, A.M. Hill, M.T. Williams, P.R.C. Howe, and A.M. Coates are with the Alliance for Research in Exercise, Nutrition and Activity (ARENA), Sansom Institute for Health Research, Division of Health Sciences, University of South Australia, Adelaide, South Australia, Australia. alison.coates@unisa.edu.au.
authors.forename: Alison M
authors.initials: AM
authors.lastname: Coates
mesh_terms: D002908:Chronic Disease; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage*; D005231:Fatty Acids, Unsaturated; D006801:Humans; D015995:Prevalence; D029424:Pulmonary Disease, Chronic Obstructive / Q000453:epidemiology*
chemical_list: D015525:Fatty Acids, Omega-3; D005231:Fatty Acids, Unsaturated
keywords: COPD; LCn-3 PUFA; chronic obstructive pulmonary disease; long-chain n-3 fatty acid; polyunsaturated fatty acid; systematic review.