+1 Recommend
1 collections
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      The effect of comorbidities on COPD assessment: a pilot study

      Read this article at

          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.



          Patients with chronic obstructive pulmonary disease (COPD) frequently suffer from comorbidities. COPD severity may be evaluated by the Global initiative for chronic Obstructive Lung Disease (GOLD) combined risk assessment score (GOLD score). Spirometry, body plethysmography, diffusing capacity of the lung for carbon monoxide (DLCO), and high-resolution computed tomography (HR-CT) measure lung function and elucidate pulmonary pathology. This study assesses associations between GOLD score and measurements of lung function in COPD patients with and without (≤1) comorbidities. It evaluates whether the presence of comorbidities influences evaluation by GOLD score of COPD severity, and questions whether GOLD score describes morbidity rather than COPD severity.


          In this prospective study, 106 patients with stable COPD were included. Patients treated for lung cancer were excluded. Demographics, oxygen saturation (SpO 2), modified Medical Research Council Dyspnea Scale, COPD exacerbations, and comorbidities were recorded. Body plethysmography and DLCO were measured, and HR-CT performed and evaluated for emphysema and airways disease. COPD severity was stratified by the GOLD score. Correlation analyses: 1) GOLD score, 2) emphysema grade, and 3) airways disease and lung function parameters, described by: forced expiratory volume in the first second in percent of expected value (FEV 1%), inspiratory capacity (IC%), total lung volume (TLC%), IC/TLC, and SpO 2. Correlation analyses between subgroups and hierarchical cluster analysis were performed.


          Significant associations were found between GOLD score and both emphysema grade (correlation coefficients [cc]: −0.2, P=0.03) and lung function parameters (cc: −0.5 to −0.7, P-values all <0.001) weakened in patients with >1 comorbidity (cc: −0.4 to −0.5, P-values all 0.001). Significant differences between subgroups were found in GOLD score and both FEV 1% (cc: −0.2, P=0.02) and IC/TLC (cc: −0.2, P=0.02). Comorbidities were associated with GOLD score and composite measures in hierarchical cluster analysis.


          The presence of comorbidities influences the relationship between GOLD score and lung function measurements. GOLD score may be more representative of morbidity than of COPD severity.

          Related collections

          Most cited references 34

          • Record: found
          • Abstract: not found
          • Article: not found


            • Record: found
            • Abstract: not found
            • Article: not found

            Reference values for residual volume, functional residual capacity and total lung capacity. ATS Workshop on Lung Volume Measurements. Official Statement of The European Respiratory Society.

             P Quanjer,  J Stocks (1995)
              • Record: found
              • Abstract: not found
              • Article: not found

              An introduction to medical statistics


                Author and article information

                Int J Chron Obstruct Pulmon Dis
                Int J Chron Obstruct Pulmon Dis
                International Journal of COPD
                International Journal of Chronic Obstructive Pulmonary Disease
                Dove Medical Press
                25 February 2015
                : 10
                : 429-438
                [1 ]Department of Respiratory Diseases, Aalborg University Hospital, Aalborg, Denmark
                [2 ]Respiratory and Critical Care Group (RCARE), Centre for Model-Based Medical Decision Support Systems, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
                [3 ]The Clinical Institute, Aalborg University Hospital, Aalborg, Denmark
                [4 ]Department of Radiology, Vendsyssel Hospital, Hjørring, Denmark
                [5 ]Department of Radiology, Horsens Regional Hospital, Horsens, Denmark
                [6 ]Department of Radiology, Aalborg University Hospital, Aalborg, Denmark
                Author notes
                Correspondence: Ulla Møller Weinreich, Department of Respiratory Diseases, Aalborg University Hospital, Mølleparkvej 4, DK-9000 Aalborg, Denmark, Tel +45 97 66 47 35, Fax +45 97 66 35 77, Email ulw@
                © 2015 Weinreich et al. This work is published by Dove Medical Press Limited, and licensed under Creative Commons Attribution – Non Commercial (unported, v3.0) License

                The full terms of the License are available at Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed.

                Original Research


                Comment on this article