Kento Sato1, Yoko Shibata2, Sumito Inoue3, Akira Igarashi4, Yoshikane Tokairin5, Keiko Yamauchi6, Tomomi Kimura7, Takako Nemoto8, Masamichi Sato9, Hiroshi Nakano10, Hiroyoshi Machida11, Michiko Nishiwaki12, Maki Kobayashi13, Sujeong Yang14, Yukihiro Minegishi15, Kodai Furuyama16, Tomoka Yamamoto17, Tetsu Watanabe18, Tsuneo Konta19, Yoshiyuki Ueno20, Takeo Kato21, Takamasa Kayama22, Isao Kubota23. 1. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: k-sato@med.id.yamagata-u.ac.jp. 2. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan; Department of Pulmonary Medicine, Fukushima Medical University School of Medicine, 1 Hikariga-Oka, Fukushima 960-1295, Japan. Electronic address: shibatay@fmu.ac.jp. 3. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: sinoue@med.id.yamagata-u.ac.jp. 4. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: akigaras@med.id.yamagata-u.ac.jp. 5. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: ytokair@med.id.yamagata-u.ac.jp. 6. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: kyamauchi@med.id.yamagata-u.ac.jp. 7. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: tomomi-i@med.id.yamagata-u.ac.jp. 8. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: n.takako@med.id.yamagata-u.ac.jp. 9. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: m-satoh@med.id.yamagata-u.ac.jp. 10. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: h-nakano@med.id.yamagata-u.ac.jp. 11. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: phirom7812@yahoo.co.jp. 12. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: m-nishi@med.id.yamagata-u.ac.jp. 13. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: m-kobayashi@med.id.yamagata-u.ac.jp. 14. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: youngishyoungster@gmail.com. 15. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: y-minegishi@med.id.yamagata-u.ac.jp. 16. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: k-furuyama@med.id.yamagata-u.ac.jp. 17. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: danses_de_travers@docomo.ne.jp. 18. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: tewatana@med.id.yamagata-u.ac.jp. 19. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: kkonta@med.id.yamagata-u.ac.jp. 20. Global Center of Excellence Program Study Group, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: y-ueno@med.id.yamagata-u.ac.jp. 21. Global Center of Excellence Program Study Group, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: tkato@med.id.yamagata-u.ac.jp. 22. Global Center of Excellence Program Study Group, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: pulmoyamagata@outlook.jp. 23. Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. Electronic address: ikubota@med.id.yamagata-u.ac.jp.
Abstract
BACKGROUND: Few studies are available regarding the annual decline of forced expiratory volume in 1s (FEV1) in chronic obstructive pulmonary disease patients with mild airflow obstruction. This study sought to clarify to what extent cigarette-smoking individuals with mild airflow obstruction lose pulmonary function annually. METHODS: From 2004 to 2006, pulmonary function tests were performed on people >40 years of age, during the annual health checkup held in Takahata, Yamagata, Japan (initial study population, n=3253). In 2011, pulmonary function tests were performed again on participants who agreed to undergo reexamination (follow-up study population, n=838). RESULTS: Smokers have decreased pulmonary function in terms of percent forced vital capacity (FVC), %FEV1, and FEV1/FVC; the stages of airflow obstruction were also more severe in smokers than never-smokers. The annual decline in FEV1 was significantly greater in smokers than in never-smokers. The median annual decline in FEV1 was most significant in individuals with mild airflow obstruction. The annual decline in FEV1 was greater in smokers with mild airflow obstruction than in smokers with moderate airflow obstruction. In analyzing the decline in %FEV1, the annual change in smokers with mild airflow obstruction was greater than that in smokers with normal spirometric values. CONCLUSION: The annual decline in FEV1 was most significant in smokers with mild airflow obstruction in a Japanese general population. This highlights the importance of early detection of chronic obstructive pulmonary disease patients among the general population in order to prevent disease progression in undiagnosed patients.
BACKGROUND: Few studies are available regarding the annual decline of forced expiratory volume in 1s (FEV1) in chronic obstructive pulmonary diseasepatients with mild airflow obstruction. This study sought to clarify to what extent cigarette-smoking individuals with mild airflow obstruction lose pulmonary function annually. METHODS: From 2004 to 2006, pulmonary function tests were performed on people >40 years of age, during the annual health checkup held in Takahata, Yamagata, Japan (initial study population, n=3253). In 2011, pulmonary function tests were performed again on participants who agreed to undergo reexamination (follow-up study population, n=838). RESULTS: Smokers have decreased pulmonary function in terms of percent forced vital capacity (FVC), %FEV1, and FEV1/FVC; the stages of airflow obstruction were also more severe in smokers than never-smokers. The annual decline in FEV1 was significantly greater in smokers than in never-smokers. The median annual decline in FEV1 was most significant in individuals with mild airflow obstruction. The annual decline in FEV1 was greater in smokers with mild airflow obstruction than in smokers with moderate airflow obstruction. In analyzing the decline in %FEV1, the annual change in smokers with mild airflow obstruction was greater than that in smokers with normal spirometric values. CONCLUSION: The annual decline in FEV1 was most significant in smokers with mild airflow obstruction in a Japanese general population. This highlights the importance of early detection of chronic obstructive pulmonary diseasepatients among the general population in order to prevent disease progression in undiagnosed patients.