1 López‐Campos, J. L., Tan, W. & Soriano, J. B. Global burden of COPD. Respirology 21, 14-23 (2016).
2 World Health Organization. Chronic respiratory diseases. https://www.who.int/health-topics/chronic-respiratory-diseases#tab=tab_1
3 Lundbäck, B. et al. Not 15 but 50% of smokers develop COPD?—report from the obstructive lung disease in Northern Sweden studies. Respir. Med. 97, 115-122 (2003).
4 Mannino, D. M. COPD: epidemiology, prevalence, morbidity and mortality, and disease heterogeneity. Chest 121, 121S-126S (2002).
5 Raherison, C. & Girodet, P. Epidemiology of COPD. Eur. Respir. Rev. 18, 213-221 (2009).
6 Laniado-Laborín, R. Smoking and chronic obstructive pulmonary disease (COPD). Parallel epidemics of the 21st century. Int. J. Environ. Res. Public Health 6, 209-224 (2009).
7 S Sharma, G. & Goodwin, J. Effect of aging on respiratory system physiology and immunology. Clin. Interv. Aging 1, 253 (2006).
8 Kerstjens, H., Rijcken, B., Schouten, J. P. & Postma, D. S. Decline of FEV1 by age and smoking status: facts, figures, and fallacies. Thorax 52, 820 (1997).
9 Camilli, A. E., Burrows, B., Knudson, R. J., Lyle, S. K. & Lebowitz, M. D. Longitudinal changes in forced expiratory volume in one second in adults: effects of smoking and smoking cessation. Am. Rev. Respir. Dis. 135, 794-799 (1987).
10 Gold, D. R. et al. Effects of cigarette smoking on lung function in adolescent boys and girls. N. Engl. J. Med. 335, 931-937 (1996).
11 Anthonisen, N. R., Connett, J. E. & Murray, R. P. Smoking and lung function of Lung Health Study participants after 11 years. Am. J. Respir. Crit. Care Med. 166, 675-679 (2002).
12 Scanlon, P. D. et al. Smoking cessation and lung function in mild-to-moderate chronic obstructive pulmonary disease: the Lung Health Study. Am. J. Respir. Crit. Care Med. 161, 381-390 (2000).
13 Anthonisen, N. R. et al. Effects of smoking intervention and the use of an inhaled anticholinergic bronchodilator on the rate of decline of FEV1: the Lung Health Study. JAMA 272, 1497-1505 (1994).
14 Lee, P. N. & Fry, J. S. Systematic review of the evidence relating FEV 1 decline to giving up smoking. BMC Med. 8, 1-29 (2010).
15 Oelsner, E. C. et al. Lung function decline in former smokers and low-intensity current smokers: a secondary data analysis of the NHLBI Pooled Cohorts Study. Lancet Respir. Med. 8, 34-44 (2020).
16 Hogg, J. C. Why does airway inflammation persist after the smoking stops? Thorax 61, 96-97 (2006).
17 Miller, M. et al. Persistent airway inflammation and emphysema progression on CT scan in ex-smokers observed for 4 years. Chest 139, 1380-1387 (2011).
18 Rutgers, S. R. et al. Ongoing airway inflammation in patients with COPD who do not currently smoke. Thorax 55, 12-18 (2000).
19 Bagaitkar, J., Demuth, D. R. & Scott, D. A. Tobacco use increases susceptibility to bacterial infection. Tob. Induc. Dis. 4, 1-10 (2008).
20 Feldman, C. & Anderson, R. Cigarette smoking and mechanisms of susceptibility to infections of the respiratory tract and other organ systems. J. Infect. 67, 169-184 (2013).
21 Stämpfli, M. R. & Anderson, G. P. How cigarette smoke skews immune responses to promote infection, lung disease and cancer. Nat. Rev. Immunol. 9, 377-384 (2009).
22 Allinson, J. P. et al. The presence of chronic mucus hypersecretion across adult life in relation to chronic obstructive pulmonary disease development. Am. J. Respir. Crit. Care Med. 193, 662-672 (2016).
23 Allinson, J. et al. The relationship between cigarette smoking intensity and chronic mucus hypersecretion (CMH) at different ages within a nationally representative birth cohort. Eur. Respir. J. 46 (2015).
24 Wang, G. et al. Persistence of smoking-induced dysregulation of miRNA expression in the small airway epithelium despite smoking cessation. PloS one 10, e0120824 (2015).
25 Tasena, H. et al. microRNA–mRNA regulatory networks underlying chronic mucus hypersecretion in COPD. Eur. Respirat. J. 52 (2018).
26 Churg, A., Tai, H., Coulthard, T., Wang, R. & Wright, J. L. Cigarette smoke drives small airway remodeling by induction of growth factors in the airway wall. Am. J. Respir. Crit. Care Med. 174, 1327-1334 (2006).
27 Jobst, B. J. et al. Longitudinal airway remodeling in active and past smokers in a lung cancer screening population. Eur. Radiol. 29, 2968-2980 (2019).
28 Bergeron, C. & Boulet, L.-P. Structural changes in airway diseases: characteristics, mechanisms, consequences, and pharmacologic modulation. Chest 129, 1068-1087 (2006).
29 Global Initiative for Chronic Obstructive Lung Disease. 2021 GOLD reports: Global strategy for prevention, diagnosis and management of chronic obstructive lung disease. https://goldcopd.org/2021-gold-reports/
30 Celli, B. R. & Halbert, R. J. Point: should we abandon FEV1/FVC< 0.70 to detect airway obstruction? No. Chest 138, 1037-1040 (2010).