Koichi Nishimura1, Toru Oga2, Mitsuhiro Tsukino3, Takashi Hajiro4, Akihiko Ikeda5, Paul W Jones6. 1. Department of Pulmonary Medicine, National Center for Geriatrics and Gerontology, Obu, Japan. Electronic address: koichi-nishimura@nifty.com. 2. Department of Respiratory Care and Sleep Control Medicine, Graduate School of Medicine, Kyoto University, 54, Kawahara, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: ogato@kuhp.kyoto-u.ac.jp. 3. Department of Respiratory Medicine, Hikone Municipal Hospital, Hikone, Japan. Electronic address: tsukino@municipal-hp.hikone.shiga.jp. 4. Department of Respiratory Medicine, Tenri Hospital, Tenri, Japan. Electronic address: takhaj@gmail.com. 5. Department of Respiratory Medicine, Nishi-Kobe Medical Center, Kobe, Japan. Electronic address: akikeda@nmc-kobe.org. 6. Division of Clinical Science, St. George's Hospital Medical School, London, England, UK. Electronic address: pjones@sgul.ac.uk.
Abstract
BACKGROUND: The Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2011 consensus report proposed a new classification system, incorporating symptoms with future risk, in subjects with chronic obstructive pulmonary disease (COPD). We hypothesized it could be applied to Japanese COPD patients. METHODS: We previously analyzed clinical factors related to 5-year mortality in 150 male outpatients with COPD. We reviewed the data and reanalyzed the relationships between the new GOLD classification and various outcomes including mortality. RESULTS: There were 51 (34.0%), 12 (8.0%), 57 (38.0%), and 30 (20.0%) patients in GOLD A (forced expiratory volume in 1s [FEV1] ≥ 50% predicted and modified Medical Research Council [mMRC] 0-1), GOLD B (FEV1 ≥ 50% predicted and mMRC ≥ 2), GOLD C (FEV1<50% predicted and mMRC 0-1), and GOLD D (FEV1 <50% predicted and mMRC ≥ 2), respectively. The GOLD 2011 classification correlated significantly with exercise capacity and multi-dimensional disease staging. Cox proportional hazards analysis revealed that, among several methods categorizing symptoms, the GOLD A-D classification was significantly associated with mortality (p=0.0055). CONCLUSION: Although the relative number of patients in each category of the combined COPD assessment classification depended on the choice of symptom measures, the categories defined by the mMRC scale (score 0-1 versus ≥ 2) were most useful for future risk assessed as mortality. GOLD A had the lowest mortality, followed by GOLD B and C, and D had the highest mortality. Exercise capacity was also stratified by the new GOLD classification.
BACKGROUND: The Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2011 consensus report proposed a new classification system, incorporating symptoms with future risk, in subjects with chronic obstructive pulmonary disease (COPD). We hypothesized it could be applied to Japanese COPDpatients. METHODS: We previously analyzed clinical factors related to 5-year mortality in 150 male outpatients with COPD. We reviewed the data and reanalyzed the relationships between the new GOLD classification and various outcomes including mortality. RESULTS: There were 51 (34.0%), 12 (8.0%), 57 (38.0%), and 30 (20.0%) patients in GOLD A (forced expiratory volume in 1s [FEV1] ≥ 50% predicted and modified Medical Research Council [mMRC] 0-1), GOLD B (FEV1 ≥ 50% predicted and mMRC ≥ 2), GOLD C (FEV1<50% predicted and mMRC 0-1), and GOLD D (FEV1 <50% predicted and mMRC ≥ 2), respectively. The GOLD 2011 classification correlated significantly with exercise capacity and multi-dimensional disease staging. Cox proportional hazards analysis revealed that, among several methods categorizing symptoms, the GOLD A-D classification was significantly associated with mortality (p=0.0055). CONCLUSION: Although the relative number of patients in each category of the combined COPD assessment classification depended on the choice of symptom measures, the categories defined by the mMRC scale (score 0-1 versus ≥ 2) were most useful for future risk assessed as mortality. GOLD A had the lowest mortality, followed by GOLD B and C, and D had the highest mortality. Exercise capacity was also stratified by the new GOLD classification.