Global, regional, and national deaths, prevalence, disability-adjusted life years, and years lived with disability for chronic obstructive pulmonary disease and asthma, 1990-2015: a systematic analysis for the Global Burden of Disease Study 2015

GBD 2015 Chronic Respiratory Disease Collaborators, Joan B Soriano, Amanuel Alemu Abajobir, Kalkidan Hassen Abate, Semaw Ferede Abera, Anurag Agrawal, Muktar Beshir Ahmed, Amani Nidhal Aichour, Ibtihel Aichour, Miloud Taki Eddine Aichour, Khurshid Alam, Noore Alam, Juma M Alkaabi, Fatma Al-Maskari, Nelson Alvis-Guzman, Alemayehu Amberbir, Yaw Ampem Amoako, Mustafa Geleto Ansha, Josep M Antó, Hamid Asayesh, Tesfay Mehari Atey, Euripide Frinel G Arthur Avokpaho, Aleksandra Barac, Sanjay Basu, Neeraj Bedi, Isabela M Bensenor, Adugnaw Berhane, Addisu Shunu Beyene, Zulfiqar A Bhutta, Stan Biryukov, Dube Jara Boneya, Michael Brauer, David O Carpenter, Daniel Casey, Devasahayam Jesudas Christopher, Lalit Dandona, Rakhi Dandona, Samath D Dharmaratne, Huyen Phuc Do, Florian Fischer, Tsegaye T Gebrehiwot, Ayele Geleto, Aloke Gopal Ghoshal, Richard F Gillum, Ibrahim Abdelmageem Mohamed Ginawi, Vipin Gupta, Simon I Hay, Mohammad T Hedayati, Nobuyuki Horita, H Dean Hosgood, Mihajlo Michael B Jakovljevic, Spencer Lewis James, Jost B Jonas, Amir Kasaeian, Yousef Saleh Khader, Ibrahim A Khalil, Ejaz Ahmad Khan, Young-Ho Khang, Jagdish Khubchandani, Luke D Knibbs, Soewarta Kosen, Parvaiz A Koul, G Anil Kumar, Cheru Tesema Leshargie, Xiaofeng Liang, Hassan Magdy Abd El Razek, Azeem Majeed, Deborah Carvalho Malta, Treh Manhertz, Neal Marquez, Alem Mehari, George A Mensah, Ted R Miller, Karzan Abdulmuhsin Mohammad, Kedir Endris Mohammed, Shafiu Mohammed, Ali H Mokdad, Mohsen Naghavi, Cuong Tat Nguyen, Grant Nguyen, Quyen Le Nguyen, Trang Huyen Nguyen, Dina Nur Anggraini Ningrum, Vuong Minh Nong, Jennifer Ifeoma Obi, Yewande E Odeyemi, Felix Akpojene Ogbo, Eyal Oren, Mahesh Pa, Eun-Kee Park, George C Patton, Katherine Paulson, Mostafa Qorbani, Reginald Quansah, Anwar Rafay, Mohammad Hifz Ur Rahman, Rajesh Kumar Rai, Salman Rawaf, Nik Reinig, Saeid Safiri, Rodrigo Sarmiento-Suarez, Benn Sartorius, Miloje Savic, Monika Sawhney, Mika Shigematsu, Mari Smith, Fentaw Tadese, George D Thurston, Roman Topor-Madry, Bach Xuan Tran, Kingsley Nnanna Ukwaja, Job F M van Boven, Vasiliy Victorovich Vlassov, Stein Emil Vollset, Xia Wan, Andrea Werdecker, Sarah Wulf Hanson, Yuichiro Yano, Hassen Hamid Yimam, Naohiro Yonemoto, Chuanhua Yu, Zoubida Zaidi, Maysaa El Sayed Zaki, Alan D Lopez, Christopher J L Murray, Theo Vos, GBD 2015 Chronic Respiratory Disease Collaborators, Joan B Soriano, Amanuel Alemu Abajobir, Kalkidan Hassen Abate, Semaw Ferede Abera, Anurag Agrawal, Muktar Beshir Ahmed, Amani Nidhal Aichour, Ibtihel Aichour, Miloud Taki Eddine Aichour, Khurshid Alam, Noore Alam, Juma M Alkaabi, Fatma Al-Maskari, Nelson Alvis-Guzman, Alemayehu Amberbir, Yaw Ampem Amoako, Mustafa Geleto Ansha, Josep M Antó, Hamid Asayesh, Tesfay Mehari Atey, Euripide Frinel G Arthur Avokpaho, Aleksandra Barac, Sanjay Basu, Neeraj Bedi, Isabela M Bensenor, Adugnaw Berhane, Addisu Shunu Beyene, Zulfiqar A Bhutta, Stan Biryukov, Dube Jara Boneya, Michael Brauer, David O Carpenter, Daniel Casey, Devasahayam Jesudas Christopher, Lalit Dandona, Rakhi Dandona, Samath D Dharmaratne, Huyen Phuc Do, Florian Fischer, Tsegaye T Gebrehiwot, Ayele Geleto, Aloke Gopal Ghoshal, Richard F Gillum, Ibrahim Abdelmageem Mohamed Ginawi, Vipin Gupta, Simon I Hay, Mohammad T Hedayati, Nobuyuki Horita, H Dean Hosgood, Mihajlo Michael B Jakovljevic, Spencer Lewis James, Jost B Jonas, Amir Kasaeian, Yousef Saleh Khader, Ibrahim A Khalil, Ejaz Ahmad Khan, Young-Ho Khang, Jagdish Khubchandani, Luke D Knibbs, Soewarta Kosen, Parvaiz A Koul, G Anil Kumar, Cheru Tesema Leshargie, Xiaofeng Liang, Hassan Magdy Abd El Razek, Azeem Majeed, Deborah Carvalho Malta, Treh Manhertz, Neal Marquez, Alem Mehari, George A Mensah, Ted R Miller, Karzan Abdulmuhsin Mohammad, Kedir Endris Mohammed, Shafiu Mohammed, Ali H Mokdad, Mohsen Naghavi, Cuong Tat Nguyen, Grant Nguyen, Quyen Le Nguyen, Trang Huyen Nguyen, Dina Nur Anggraini Ningrum, Vuong Minh Nong, Jennifer Ifeoma Obi, Yewande E Odeyemi, Felix Akpojene Ogbo, Eyal Oren, Mahesh Pa, Eun-Kee Park, George C Patton, Katherine Paulson, Mostafa Qorbani, Reginald Quansah, Anwar Rafay, Mohammad Hifz Ur Rahman, Rajesh Kumar Rai, Salman Rawaf, Nik Reinig, Saeid Safiri, Rodrigo Sarmiento-Suarez, Benn Sartorius, Miloje Savic, Monika Sawhney, Mika Shigematsu, Mari Smith, Fentaw Tadese, George D Thurston, Roman Topor-Madry, Bach Xuan Tran, Kingsley Nnanna Ukwaja, Job F M van Boven, Vasiliy Victorovich Vlassov, Stein Emil Vollset, Xia Wan, Andrea Werdecker, Sarah Wulf Hanson, Yuichiro Yano, Hassen Hamid Yimam, Naohiro Yonemoto, Chuanhua Yu, Zoubida Zaidi, Maysaa El Sayed Zaki, Alan D Lopez, Christopher J L Murray, Theo Vos

Abstract

Background: Chronic obstructive pulmonary disease (COPD) and asthma are common diseases with a heterogeneous distribution worldwide. Here, we present methods and disease and risk estimates for COPD and asthma from the Global Burden of Diseases, Injuries, and Risk Factors (GBD) 2015 study. The GBD study provides annual updates on estimates of deaths, prevalence, and disability-adjusted life years (DALYs), a summary measure of fatal and non-fatal disease outcomes, for over 300 diseases and injuries, for 188 countries from 1990 to the most recent year.

Methods: We estimated numbers of deaths due to COPD and asthma using the GBD Cause of Death Ensemble modelling (CODEm) tool. First, we analysed data from vital registration and verbal autopsy for the aggregate category of all chronic respiratory diseases. Subsequently, models were run for asthma and COPD relying on covariates to predict rates in countries that have incomplete or no vital registration data. Disease estimates for COPD and asthma were based on systematic reviews of published papers, unpublished reports, surveys, and health service encounter data from the USA. We used the Global Initiative of Chronic Obstructive Lung Disease spirometry-based definition as the reference for COPD and a reported diagnosis of asthma with current wheeze as the definition of asthma. We used a Bayesian meta-regression tool, DisMod-MR 2.1, to derive estimates of prevalence and incidence. We estimated population-attributable fractions for risk factors for COPD and asthma from exposure data, relative risks, and a theoretical minimum exposure level. Results were stratified by Socio-demographic Index (SDI), a composite measure of income per capita, mean years of education over the age of 15 years, and total fertility rate.

Findings: In 2015, 3·2 million people (95% uncertainty interval [UI] 3·1 million to 3·3 million) died from COPD worldwide, an increase of 11·6% (95% UI 5·3 to 19·8) compared with 1990. There was a decrease in age-standardised death rate of 41·9% (37·7 to 45·1) but this was counteracted by population growth and ageing of the global population. From 1990 to 2015, the prevalence of COPD increased by 44·2% (41·7 to 46·6), whereas age-standardised prevalence decreased by 14·7% (13·5 to 15·9). In 2015, 0·40 million people (0·36 million to 0·44 million) died from asthma, a decrease of 26·7% (-7·2 to 43·7) from 1990, and the age-standardised death rate decreased by 58·8% (39·0 to 69·0). The prevalence of asthma increased by 12·6% (9·0 to 16·4), whereas the age-standardised prevalence decreased by 17·7% (15·1 to 19·9). Age-standardised DALY rates due to COPD increased until the middle range of the SDI before reducing sharply. Age-standardised DALY rates due to asthma in both sexes decreased monotonically with rising SDI. The relation between with SDI and DALY rates due to asthma was attributed to variation in years of life lost (YLLs), whereas DALY rates due to COPD varied similarly for YLLs and years lived with disability across the SDI continuum. Smoking and ambient particulate matter were the main risk factors for COPD followed by household air pollution, occupational particulates, ozone, and secondhand smoke. Together, these risks explained 73·3% (95% UI 65·8 to 80·1) of DALYs due to COPD. Smoking and occupational asthmagens were the only risks quantified for asthma in GBD, accounting for 16·5% (14·6 to 18·7) of DALYs due to asthma.

Interpretation: Asthma was the most prevalent chronic respiratory disease worldwide in 2015, with twice the number of cases of COPD. Deaths from COPD were eight times more common than deaths from asthma. In 2015, COPD caused 2·6% of global DALYs and asthma 1·1% of global DALYs. Although there are laudable international collaborative efforts to make surveys of asthma and COPD more comparable, no consensus exists on case definitions and how to measure disease severity for population health measurements like GBD. Comparisons between countries and over time are important, as much of the chronic respiratory burden is either preventable or treatable with affordable interventions.

Funding: Bill & Melinda Gates Foundation.

Copyright © 2017 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.

Figures

Figure 1
Figure 1
Age-standardised DALY rate per 100 000 people due to COPD by country, both sexes, 2015 DALYs=disability-adjusted life years. COPD=chronic obstructive pulmonary disease. ATG=Antigua and Barbuda. FSM=Federated States of Micronesia. Isl=islands. LCA=Saint Lucia. TLS=Timor-Leste. TTO=Trinidad and Tobago. VCT=Saint Vincent and the Grenadines.
Figure 2
Figure 2
Age-standardised DALY rate per 100 000 people due to asthma, by country, both sexes, 2015 DALYs=disability-adjusted life years. ATG=Antigua and Barbuda. FSM=Federated States of Micronesia. Isl=islands. LCA=Saint Lucia. TLS=Timor-Leste. TTO=Trinidad and Tobago. VCT=Saint Vincent and the Grenadines.
Figure 3
Figure 3
Expected relationship between all-age DALY rates due to COPD and asthma and SDI by sex, 2015 DALYs=disability-adjusted life years. COPD=chronic obstructive pulmonary disease. SDI=Socio-demographic Index.
Figure 4
Figure 4
Expected relationship between age-standardised DALY rates due to COPD and asthma and SDI by sex, 2015 DALYs=disability-adjusted life years. COPD=chronic obstructive pulmonary disease. SDI=Socio-demographic Index.
Figure 5
Figure 5
Expected relationship between age-standardised DALY rates due to COPD and asthma and SDI by YLLs and YLDs, 2015 DALYs=disability-adjusted life years. COPD=chronic obstructive pulmonary disease. SDI=Socio-demographic Index. YLLs=years of life lost. YLDs=years lived with disability.
Figure 6
Figure 6
Age-standardised DALY rates due to COPD by 21 GBD world regions and the expected value based on the SDI by sex, 1990–2015 The black line represents the expected value of a disease rate based on a LOESS regression of all years of estimates by GBD locations and their SDI value. DALYs=disability-adjusted life years. COPD=chronic obstructive pulmonary disease. GBD=Global Burden of Disease. SDI=Socio-demographic Index. LOESS=locally weighted regression and smoothing scatterplots.
Figure 7
Figure 7
Age-standardised DALY rates due to asthma by 21 GBD world regions and the expected value based on the SDI by sex, 1990–2015 The black line represents the expected value of a disease rate based on a LOESS regression of all years of estimates by GBD locations and their SDI value. DALYs=disability-adjusted life years. GBD=Global Burden of Disease. SDI=Socio-demographic Index. LOESS=locally weighted regression and smoothing scatterplots.
Figure 8
Figure 8
Age-standardised DALY rates due to COPD and asthma attributable to seven risk factors, both sexes, 2015 COPD=chronic obstructive pulmonary disease. DALYs=disability-adjusted life years.
Figure 9
Figure 9
Contribution of behavioural and environmental and occupational risks to DALYs due to COPD per 100 000 people in locations grouped by SDI quintiles, 2015 Environmental and occupational: ambient particulate matter, household air pollution, occupational particulates, and ozone. Behavioural: smoking and second-hand smoke. Behavioural environmental: ambient particulate matter, household air pollution, occupational particulates, ozone, smoking, and second-hand smoke. DALYs=disability-adjusted life years. COPD=chronic obstructive pulmonary disease. SDI=Socio-demographic Index.

References

    1. GBD 2015 Mortality and Causes of Death Collaborators Global, regional, and national life expectancy, all-cause mortality, and cause-specific mortality for 249 causes of death, 1980–2015: a systematic analysis for the Global Burden of Disease Study 2015. Lancet. 2016;388:1459–1544.
    1. GBD 2015 Disease and Injury Incidence and Prevalence Collaborators Global, regional, and national incidence, prevalence, and years lived with disability for 310 diseases and injuries, 1990–2015: a systematic analysis for the Global Burden of Disease Study 2015. Lancet. 2016;388:1545–1602.
    1. Burney P, Jarvis D, Perez-Padilla R. The global burden of chronic respiratory disease in adults. Int J Tuberc Lung Dis. 2015;19:10–20.
    1. Yáñez A, Cho S-H, Soriano JB. Asthma in the elderly: what we know and what we have yet to know. World Allergy Organ J. 2014;7:8.
    1. Wurst KE, Rheault TR, Edwards L, Tal-Singer R, Agusti A, Vestbo J. A comparison of COPD patients with and without ACOS in the ECLIPSE study. Eur Respir J. 2016;47:1559–1562.
    1. de Marco R, Marcon A, Rossi A. Asthma, COPD and overlap syndrome: a longitudinal study in young European adults. Eur Respir J. 2015;46:671–679.
    1. Barnes PJ. Asthma-COPD overlap. Chest. 2016;149:7–8.
    1. Sin DD, Miravitlles M, Mannino DM. What is asthma-COPD overlap syndrome? Towards a consensus definition from a round table discussion. Eur Respir J. 2016;48:664–673.
    1. BOLD-COPD International Research platform. (accessed Feb 7, 2017).
    1. Caballero A, Torres-Duque CA, Jaramillo C. Prevalence of COPD in five Colombian cities situated at low, medium, and high altitude (PREPOCOL study) Chest. 2008;133:343–349.
    1. Menezes AMB, Victora CG, Perez-Padilla R, PLATINO Team The Platino project: methodology of a multicenter prevalence survey of chronic obstructive pulmonary disease in major Latin American cities. BMC Med Res Methodol. 2004;4:15.
    1. Vollmer WM, Gíslason T, Burney P. Comparison of spirometry criteria for the diagnosis of COPD: results from the BOLD study. Eur Respir J. 2009;34:588–597.
    1. Quinn CE, Soriano JB, Chen R, Zhou Y. Epidemiology of COPD. In: Quinn CE, editor. 100 questions & answers about chronic obstructive pulmonary disease (COPD) Jones & Bartlett Learning; Burlington, MA: 2005.
    1. Vogelmeier CF, Criner GJ, Martinez FJ. Global strategy for the diagnosis, management, and prevention of chronic obstructive lung disease 2017 report: GOLD executive summary. Eur Respir J. 2017;49:1750214.
    1. Quanjer PH, Stanojevic S, Cole TJ. Multi-ethnic reference values for spirometry for the 3–95-yr age range: the global lung function 2012 equations. Eur Respir J. 2012;40:1324–1343.
    1. Lamprecht B, Soriano JB, Studnicka M. Determinants of underdiagnosis of COPD in national and international surveys. Chest. 2015;148:971–985.
    1. Soriano JB, Zielinski J, Price D. Screening for and early detection of chronic obstructive pulmonary disease. Lancet. 2009;374:721–732.
    1. Pearce N, Sunyer J, Cheng S. Comparison of asthma prevalence in the ISAAC and the ECRHS. ISAAC Steering Committee and the European Community Respiratory Health Survey. International Study of Asthma and Allergies in Childhood. Eur Respir J. 2000;16:420–426.
    1. Toelle BG, Peat JK, Salome CM, Mellis CM, Woolcock AJ. Toward a definition of asthma for epidemiology. Am Rev Respir Dis. 1992;146:633–637.
    1. Riiser A, Hovland V, Carlsen K-H, Mowinckel P, Lødrup Carlsen KC. Does bronchial hyperresponsiveness in childhood predict active asthma in adolescence? Am J Respir Crit Care Med. 2012;186:493–500.
    1. Pekkanen J, Pearce N. Defining asthma in epidemiological studies. Eur Respir J. 1999;14:951–957.
    1. Pattemore PK, Asher MI, Harrison AC, Mitchell EA, Rea HH, Stewart AW. The interrelationship among bronchial hyperresponsiveness, the diagnosis of asthma, and asthma symptoms. Am Rev Respir Dis. 1990;142:549–554.
    1. GBD 2015 Risk Factors Collaborators Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks, 1990–2015: a systematic analysis for the Global Burden of Disease Study 2015. Lancet. 2016;388:1659–1724.
    1. Tilert T, Dillon C, Paulose-Ram R, Hnizdo E, Doney B. Estimating the US prevalence of chronic obstructive pulmonary disease using pre- and post-bronchodilator spirometry: the National Health and Nutrition Examination Survey (NHANES) 2007–2010. Respir Res. 2013;14:103.
    1. Johannessen A, Omenaas ER, Bakke PS, Gulsvik A. Implications of reversibility testing on prevalence and risk factors for chronic obstructive pulmonary disease: a community study. Thorax. 2005;60:842–847.
    1. Pérez-Padilla R, Hallal PC, Vázquez-García JC. Impact of bronchodilator use on the prevalence of COPD in population-based samples. COPD. 2007;4:113–120.
    1. Shirtcliffe P, Weatherall M, Marsh S. COPD prevalence in a random population survey: a matter of definition. Eur Respir J. 2007;30:232–239.
    1. Mohamed Hoesein FAA, Zanen P, Sachs APE, Verheij TJM, Lammers J-WJ, Broekhuizen BDL. Spirometric thresholds for diagnosing COPD: 0·70 or LLN, pre- or post-dilator values? COPD. 2012;9:338–343.
    1. Ko FWS, Woo J, Tam W. Prevalence and risk factors of airflow obstruction in an elderly Chinese population. Eur Respir J. 2008;32:1472–1478.
    1. Swanney MP, Ruppel G, Enright PL. Using the lower limit of normal for the FEV1/FVC ratio reduces the misclassification of airway obstruction. Thorax. 2008;63:1046–1051.
    1. Lindberg A, Bjerg A, Bjerg-Bäcklund A, Rönmark E, Larsson L-G, Lundbäck B. Prevalence and underdiagnosis of COPD by disease severity and the attributable fraction of smoking report from the Obstructive Lung Disease in Northern Sweden Studies. Respir Med. 2006;100:264–272.
    1. US Department of Health and Human Services Medical expenditure panel survey home. (accessed Feb 9, 2017).
    1. Ware J, Kosinski M, Keller SD. A 12-Item Short-Form Health Survey: construction of scales and preliminary tests of reliability and validity. Med Care. 1996;34:220–233.
    1. Brauer M, Freedman G, Frostad J. Ambient air pollution exposure estimation for the Global Burden of Disease 2013. Environ Sci Technol. 2016;50:79–88.
    1. International Labour Organization Key indicators of the labour market. (accessed Aug 1, 2017).
    1. Jerrett M, Burnett RT, Pope CA. Long-term ozone exposure and mortality. N Engl J Med. 2009;360:1085–1095.
    1. Salomon JA, Haagsma JA, Davis A. Disability weights for the Global Burden of Disease 2013 study. Lancet Glob Health. 2015;3:e712–e723.
    1. Stevens GA, Alkema L, Black RE. Guidelines for Accurate and Transparent Health Estimates Reporting: the GATHER statement. Lancet. 2016;388:e19–e23.
    1. Global Initiative for Asthma 2017 GINA report: global strategy for asthma management and prevention. (accessed March 23, 2017).
    1. Burney PGJ, Hooper RL. The use of ethnically specific norms for ventilatory function in African-American and white populations. Int J Epidemiol. 2012;41:782–790.
    1. Soriano JB, Parkes G. Remember elephants and icebergs… ‘Your lung function should be here, but it is there!’. Eur Respir J. 2009;33:715–716.
    1. Halbert RJ, Natoli JL, Gano A, Badamgarav E, Buist AS, Mannino DM. Global burden of COPD: systematic review and meta-analysis. Eur Respir J. 2006;28:523–532.
    1. Masoli M, Fabian D, Holt S, Beasley R, Global Initiative for Asthma (GINA) Program The global burden of asthma: executive summary of the GINA Dissemination Committee report. Allergy. 2004;59:469–478.
    1. To T, Stanojevic S, Moores G. Global asthma prevalence in adults: findings from the cross-sectional world health survey. BMC Public Health. 2012;12:204.
    1. Burney P, Jithoo A, Kato B. Chronic obstructive pulmonary disease mortality and prevalence: the associations with smoking and poverty—a BOLD analysis. Thorax. 2014;69:465–473.
    1. Bousquet J, Anto J, Sunyer J. Pooling birth cohorts in allergy and asthma: European Union-funded initiatives—a MeDALL, CHICOS, ENRIECO, and GA2LEN joint paper. Int Arch Allergy Immunol. 2013;161:1–10.
    1. Kohansal R, Soriano JB, Agusti A. Investigating the natural history of lung function: facts, pitfalls, and opportunities. Chest. 2009;135:1330–1341.
    1. Bilano V, Gilmour S, Moffiet T. Global trends and projections for tobacco use, 1990–2025: an analysis of smoking indicators from the WHO Comprehensive Information Systems for Tobacco Control. Lancet. 2015;385:966–976.
    1. Ng M, Freeman MK, Fleming TD. Smoking prevalence and cigarette consumption in 187 countries, 1980–2012. JAMA. 2014;311:183–192.
    1. GBD 2015 Tobacco Collaborators Smoking prevalence and attributable disease burden in 195 countries and territories, 1990–2015: a systematic analysis from the Global Burden of Disease Study 2015. Lancet. 2017;389:1885–1906.
    1. Buist AS, McBurnie MA, Vollmer WM. International variation in the prevalence of COPD (the BOLD Study): a population-based prevalence study. Lancet. 2007;370:741–750.
    1. Lee C-H, Lee M-C, Lin H-H. Pulmonary tuberculosis and delay in anti-tuberculous treatment are important risk factors for chronic obstructive pulmonary disease. PLoS One. 2012;7:e37978.
    1. Shaheen SO, Barker DJ, Holgate ST. Do lower respiratory tract infections in early childhood cause chronic obstructive pulmonary disease? Am J Respir Crit Care Med. 1995;151:1649–1651.
    1. Mannino DM, Buist AS. Global burden of COPD: risk factors, prevalence, and future trends. Lancet. 2007;370:765–773.
    1. Guarnieri M, Balmes JR. Outdoor air pollution and asthma. Lancet. 2014;383:1581–1592.
    1. Khreis H, Kelly C, Tate J, Parslow R, Lucas K, Nieuwenhuijsen M. Exposure to traffic-related air pollution and risk of development of childhood asthma: a systematic review and meta-analysis. Environ Int. 2017;100:1–31.
    1. Garcia-Aymerich J, Lange P, Benet M, Schnohr P, Antó JM. Regular physical activity modifies smoking-related lung function decline and reduces risk of chronic obstructive pulmonary disease: a population-based cohort study. Am J Respir Crit Care Med. 2007;175:458–463.
    1. Garcia-Aymerich J, Lange P, Benet M, Schnohr P, Antó JM. Regular physical activity reduces hospital admission and mortality in chronic obstructive pulmonary disease: a population based cohort study. Thorax. 2006;61:772–778.
    1. Verlato G, Nguyen G, Marchetti P. Smoking and new-onset asthma in a prospective study on Italian adults. Int Arch Allergy Immunol. 2016;170:149–157.
    1. Polosa R, Morjaria JB, Caponnetto P. Persisting long term benefits of smoking abstinence and reduction in asthmatic smokers who have switched to electronic cigarettes. Discov Med. 2016;21:99–108.
    1. Wong GWK, Chow CM. Childhood asthma epidemiology: insights from comparative studies of rural and urban populations. Pediatr Pulmonol. 2008;43:107–116.
    1. Strachan DP. Family size, infection and atopy: the first decade of the ‘hygiene hypothesis’. Thorax. 2000;55(suppl 1):S2–10.
    1. Douwes J, Pearce N. Asthma and the westernization ‘package’. Int J Epidemiol. 2002;31:1098–1102.
    1. Guibas GV, Manios Y, Xepapadaki P. The obesity-asthma link in different ages and the role of body mass index in its investigation: findings from the Genesis and Healthy Growth Studies. Allergy. 2013;68:1298–1305.
    1. Antó JM, Sunyer J, Basagaña X. Risk factors of new-onset asthma in adults: a population-based international cohort study. Allergy. 2010;65:1021–1030.
    1. Fuchs O, Bahmer T, Rabe KF, von Mutius E. Asthma transition from childhood into adulthood. Lancet Respir Med. 2017;5:224–234.
    1. van Schayck CP, van der Heijden FMMA, van den Boom G, Tirimanna P, van Herwaarden CLA. Underdiagnosis of asthma: is the doctor or the patient to blame? The DIMCA project. Thorax. 2000;55:562–565.
    1. Bloomberg Philanthropies Data for health. (accessed March 23, 2017).

Source: PubMed

3
Abonneren