title: Transfer factor for carbon monoxide in patients with COPD and diabetes: results from the German COSYCONET cohort.
abstract: An impairment of CO diffusing capacity has been shown in diabetic patients without lung disease. We analyzed how diffusing capacity in patients with COPD is affected by the concurrent diagnosis of diabetes.
  
  
  
  Data from the initial visit of the German COPD cohort COSYCONET were used for analysis. 2575 patients with complete lung function data were included, among them 358 defined as diabetics with a reported physician diagnosis of diabetes and/or specific medication. Pairwise comparisons between groups and multivariate regression models were used to identify variables predicting the CO transfer factor (TLCO%pred) and the transfer coefficient (KCO%pred).
  
  
  
  COPD patients with diabetes differed from those without diabetes regarding lung function, anthropometric, clinical and laboratory parameters. Moreover, gender was an important covariate. After correction for lung function, gender and body mass index (BMI), TLCO%pred did not significantly differ between patients with and without diabetes. The results for the transfer coefficient KCO were similar, demonstrating an important role of the confounding factors RV%pred, TLC%pred, ITGV%pred, FEV1%pred, FEV1/FVC, age, packyears, creatinine and BMI. There was not even a tendency towards lower values in diabetes.
  
  
  
  The analysis of data from a COPD cohort showed no significant differences of CO transport parameters between COPD patients with and without diabetes, if BMI, gender and the reduction in lung volumes were taken into account. This result is in contrast to observations in lung-healthy subjects with diabetes and raises the question which factors, among them potential anti-inflammatory effects of anti-diabetes medication are responsible for this finding.
authors.affiliation: Department of Internal Medicine V, University of Munich, Comprehensive Pneumology Center, Member of the German Center for Lung Research, Ziemssenstr. 1, 80336, Munich, Germany. kathrin.kahnert@med.uni-muenchen.de.
authors.forename: Kathrin
authors.initials: K
authors.lastname: Kahnert
authors.affiliation: Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, Ludwig-Maximilians-Universität München, Ziemssenstr. 1, 80336, Munich, Germany.
authors.forename: Tanja
authors.initials: T
authors.lastname: Lucke
authors.affiliation: Institute for Biostatistics, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Biertz
authors.affiliation: Department of Internal Medicine IV, University of Munich, Ziemssenstr. 1, 80336, Munich, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Lechner
authors.affiliation: Pulmonary Research Institute at LungenClinic Grosshansdorf, Airway Research Center North, Member of the German Center for Lung Research, Woehrendamm 80, 22927, Grosshansdorf, Germany.
authors.forename: Henrik
authors.initials: H
authors.lastname: Watz
authors.affiliation: Department of Respiratory Medicine, University of Marburg, University Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research, Baldingerstraße, 35043, Marburg, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Alter
authors.affiliation: Department of Internal Medicine V - Pulmonology, Allergology, Respiratory Intensive Care Medicine, Saarland University Hospital, Kirrberger Straße 1, 66424, Homburg, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Bals
authors.affiliation: Department of Internal Medicine V, University of Munich, Comprehensive Pneumology Center, Member of the German Center for Lung Research, Ziemssenstr. 1, 80336, Munich, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Behr
authors.affiliation: Institute of Health Economics and Health Care Management, Helmholtz Zentrum München (GmbH) - German Research Center for Environmental Health, Member of the German Center for Lung Research, Comprehensive Pneumology Center Munich (CPC-M), Ingolstaedter Landstr. 1, 85764, Neuherberg, Germany.
authors.forename: Rolf
authors.initials: R
authors.lastname: Holle
authors.affiliation: Department of Internal Medicine V, University of Munich, Comprehensive Pneumology Center, Member of the German Center for Lung Research, Ziemssenstr. 1, 80336, Munich, Germany.
authors.forename: Rudolf M
authors.initials: RM
authors.lastname: Huber
authors.affiliation: Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, Ludwig-Maximilians-Universität München, Ziemssenstr. 1, 80336, Munich, Germany.|Institute of Epidemiology I, Helmholtz Zentrum München - German Research Center for Environmental Health, Ingolstaedter Landstr. 1, 85764, Neuherberg, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Karrasch
authors.affiliation: Department of Internal Medicine B - Cardiology, Intensive Care, Pulmonary Medicine and Infectious Diseases, Scientific Division of Pneumology and Pneumological Epidemiology, University Medicine Greifswald, Ferdinand-Sauerbruch-Strasse, 17475, Greifswald, Germany.
authors.forename: Beate
authors.initials: B
authors.lastname: Stubbe
authors.affiliation: Institute of Health Economics and Health Care Management, Helmholtz Zentrum München (GmbH) - German Research Center for Environmental Health, Member of the German Center for Lung Research, Comprehensive Pneumology Center Munich (CPC-M), Ingolstaedter Landstr. 1, 85764, Neuherberg, Germany.
authors.forename: Margarethe
authors.initials: M
authors.lastname: Wacker
authors.affiliation: ASCONET Study Coordination Office, University of Marburg, Baldingerstraße, 35043, Marburg, Germany.
authors.forename: Sandra
authors.initials: S
authors.lastname: Söhler
authors.affiliation: Department of Respiratory Medicine, Maastricht University Medical Center, P. Debyelaan 25, 6202 AZ, Maastricht, The Netherlands.
authors.forename: Emiel F M
authors.initials: EF
authors.lastname: Wouters
authors.affiliation: Department of Respiratory Medicine, University of Marburg, University Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research, Baldingerstraße, 35043, Marburg, Germany.
authors.forename: Claus
authors.initials: C
authors.lastname: Vogelmeier
authors.affiliation: Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, Ludwig-Maximilians-Universität München, Ziemssenstr. 1, 80336, Munich, Germany.
authors.forename: Rudolf A
authors.initials: RA
authors.lastname: Jörres
mesh_terms: D000368:Aged; D002245:Carbon Dioxide / Q000097:blood*; D002248:Carbon Monoxide; D015331:Cohort Studies; D015897:Comorbidity; D003920:Diabetes Mellitus / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology*; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011653:Pulmonary Diffusing Capacity; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology*; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity
chemical_list: D002245:Carbon Dioxide; D002248:Carbon Monoxide
keywords: COPD; Diabetes; Diffusing capacity; Lung function