Original Article
Diagnosis of chronic obstructive pulmonary disease earlier than current Global Initiative for Obstructive Lung Disease guidelines using a feasible spirometry parameter (maximal-mid expiratory flow/forced vital capacity)
Chronic Respiratory Disease 10(4) 191–196 ª The Author(s) 2013 Reprints and permission: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/1479972313507461 crd.sagepub.com
Majid Mirsadraee1, Mohammad Hosein Boskabady2 and Davood Attaran3
Abstract Some patients suffer from clinical symptoms of chronic obstructive pulmonary disease (COPD) but their pulmonary function tests are in the normal range (at risk group). The objective of this study was to discover a practical test to distinguish these patients from non-COPD subjects. A total of 77 subjects including 40 COPD patients, 37 subjects at risk for developing COPD, and 32 control subjects were entered in this study. The accuracy of maximal-mid expiratory flow (MMEF)/forced vital capacity (FVC) for the diagnosis of COPD in at risk patients and its capability to differentiate from early COPD and normal patients were evaluated. Body plethysmography was used for measurement of lung volume as the Global Initiative for Obstructive Lung Disease standard. MMEF/FVC in the at risk group of COPD (0.73 + 0.19) was significantly lower than the normal control group (0.9 + 0.24, respectively), and also, it was significantly higher than the COPD group (0.31 + 0.17). There was significant correlation between the MMEF/FVC and amount of smoking measured by pack year (r2 ¼ 0.112, p ¼ 0.005) and stages of COPD (Spearman’s r ¼ 0.82, p ¼ 0.0001). Early stage COPD (smoker subjects without spirometry derangement) can be diagnosed by MMEF/FVC. Using this tool we may be able to detect this highly preventable disease at an earlier stage. Keywords Chronic bronchitis, COPD, early diagnosis, MMEF/FVC, dysanapsis
Introduction Chronic obstructive pulmonary disease (COPD) is a slow progressive disease and is valuable for early detection physiologic evaluations such as the spirometry.1 According to the last Global Initiative for Obstructive Lung Disease (GOLD) criteria for staging COPD, the mild stage is a forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) below 70%.2 The at risk stage is the mildest form of this disease with the FEV1/FVC and FEV1 being in the normal range.2 Recent revisions in the GOLD guideline do not persist with the significance of the at risk group.3 According to a previous screening study in
1
2
3
Department of Internal Medicine, Islamic Azad UniversityMashhad Branch, Mashhad, Islamic Republic of Iran Applied Physiology Research Centre and Department of Physiology, School of Medicine, Mashhad, University of Medical Sciences, Mashhad, Islamic Republic of Iran Department of Pulmonary Medicine, Mashhad University of Medical Science, Mashhad, Islamic Republic of Iran
Corresponding author: Majid Mirsadraee, Department of Internal Medicine, Islamic Azad University-Mashhad Branch, No 80, 15th Kosar, Kosar Ave., Vakilabad Blv, Mashhad 91786, Islamic Republic of Iran. Email: [email protected]
Downloaded from crd.sagepub.com at James Cook University on March 16, 2015
192
Chronic Respiratory Disease 10(4)
Table 1. Classification and staging of COPD according to GOLD guidelines which used in this study. Stage of COPD 1 2 3 4
FEV1 (%)
FEV1/FVC (%)
>80 50–80 30–50
Diagnosis of chronic obstructive pulmonary disease earlier than current Global Initiative for Obstructive Lung Disease guidelines using a feasible spirometry parameter (maximal-mid expiratory flow/forced vital capacity)
Chronic Respiratory Disease 10(4) 191–196 ª The Author(s) 2013 Reprints and permission: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/1479972313507461 crd.sagepub.com
Majid Mirsadraee1, Mohammad Hosein Boskabady2 and Davood Attaran3
Abstract Some patients suffer from clinical symptoms of chronic obstructive pulmonary disease (COPD) but their pulmonary function tests are in the normal range (at risk group). The objective of this study was to discover a practical test to distinguish these patients from non-COPD subjects. A total of 77 subjects including 40 COPD patients, 37 subjects at risk for developing COPD, and 32 control subjects were entered in this study. The accuracy of maximal-mid expiratory flow (MMEF)/forced vital capacity (FVC) for the diagnosis of COPD in at risk patients and its capability to differentiate from early COPD and normal patients were evaluated. Body plethysmography was used for measurement of lung volume as the Global Initiative for Obstructive Lung Disease standard. MMEF/FVC in the at risk group of COPD (0.73 + 0.19) was significantly lower than the normal control group (0.9 + 0.24, respectively), and also, it was significantly higher than the COPD group (0.31 + 0.17). There was significant correlation between the MMEF/FVC and amount of smoking measured by pack year (r2 ¼ 0.112, p ¼ 0.005) and stages of COPD (Spearman’s r ¼ 0.82, p ¼ 0.0001). Early stage COPD (smoker subjects without spirometry derangement) can be diagnosed by MMEF/FVC. Using this tool we may be able to detect this highly preventable disease at an earlier stage. Keywords Chronic bronchitis, COPD, early diagnosis, MMEF/FVC, dysanapsis
Introduction Chronic obstructive pulmonary disease (COPD) is a slow progressive disease and is valuable for early detection physiologic evaluations such as the spirometry.1 According to the last Global Initiative for Obstructive Lung Disease (GOLD) criteria for staging COPD, the mild stage is a forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) below 70%.2 The at risk stage is the mildest form of this disease with the FEV1/FVC and FEV1 being in the normal range.2 Recent revisions in the GOLD guideline do not persist with the significance of the at risk group.3 According to a previous screening study in
1
2
3
Department of Internal Medicine, Islamic Azad UniversityMashhad Branch, Mashhad, Islamic Republic of Iran Applied Physiology Research Centre and Department of Physiology, School of Medicine, Mashhad, University of Medical Sciences, Mashhad, Islamic Republic of Iran Department of Pulmonary Medicine, Mashhad University of Medical Science, Mashhad, Islamic Republic of Iran
Corresponding author: Majid Mirsadraee, Department of Internal Medicine, Islamic Azad University-Mashhad Branch, No 80, 15th Kosar, Kosar Ave., Vakilabad Blv, Mashhad 91786, Islamic Republic of Iran. Email: [email protected]
Downloaded from crd.sagepub.com at James Cook University on March 16, 2015
192
Chronic Respiratory Disease 10(4)
Table 1. Classification and staging of COPD according to GOLD guidelines which used in this study. Stage of COPD 1 2 3 4
FEV1 (%)
FEV1/FVC (%)
>80 50–80 30–50
