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<article article-type="editorial" dtd-version="1.0" xml:lang="en" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id journal-id-type="publisher-id">KJIM</journal-id>
<journal-title-group>
<journal-title>The Korean Journal of Internal Medicine</journal-title><abbrev-journal-title>Korean J Intern Med</abbrev-journal-title></journal-title-group>
<issn pub-type="ppub">1226-3303</issn>
<issn pub-type="epub">2005-6648</issn>
<publisher>
<publisher-name>The Korean Association of Internal Medicine</publisher-name></publisher></journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.3904/kjim.2016.196</article-id>
<article-id pub-id-type="publisher-id">kjim-2016-196</article-id>
<article-categories>
<subj-group>
<subject>Editorial</subject></subj-group></article-categories>
<title-group>
<article-title>High prevalence of chronic obstructive pulmonary disease in Korea</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name><surname>Rhee</surname><given-names>Chin Kook</given-names></name>
<xref ref-type="corresp" rid="c1-kjim-2016-196"/>
</contrib>
<aff id="af1-kjim-2016-196">
Division of Pulmonary, Allergy and Critical Care Medicine, Department of Internal Medicine, College of Medicine, Seoul St. Mary’s Hospital, The Catholic University of Korea, Seoul, <country>Korea</country></aff>
</contrib-group>
<author-notes>
<corresp id="c1-kjim-2016-196">Correspondence to Chin Kook Rhee, M.D. Division of Pulmonary, Allergy and Critical Care Medicine, Department of Internal Medicine, College of Medicine, Seoul St. Mary’s Hospital, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, Seoul 06591, Korea Tel: +82-2-2258-6067 Fax: +82-2-599-3589 E-mail: <email>chinkook@catholic.ac.kr</email>.</corresp>
</author-notes>
<pub-date pub-type="ppub">
<month>7</month>
<year>2016</year></pub-date>
<pub-date pub-type="epub">
<day>1</day>
<month>7</month>
<year>2016</year></pub-date>
<volume>31</volume>
<issue>4</issue>
<fpage>651</fpage>
<lpage>652</lpage>
<history>
<date date-type="received">
<day>22</day>
<month>06</month>
<year>2016</year></date>
<date date-type="accepted">
<day>24</day>
<month>06</month>
<year>2016</year></date>
</history>
<permissions>
<copyright-statement>Copyright &#x000A9; 2016 The Korean Association of Internal Medicine</copyright-statement>
<copyright-year>2016</copyright-year>
<license>
<license-p>This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (<ext-link ext-link-type="uri" xlink:href="http://creativecommons.org/licenses/by-nc/3.0/">http://creativecommons.org/licenses/by-nc/3.0/</ext-link>) which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original work is properly cited.</license-p></license></permissions>
</article-meta></front>
<body>
<p>See Article on Page <related-article related-article-type="commentary-article" id="ra1-kjim-2016-196" vol="31" page="685" ext-link-type="pmc">685-693</related-article></p>
<p>South Korea has a very high prevalence of chronic obstructive pulmonary dis&#x000ad;ease (COPD). According to data from the Fourth Korean National Health and Nutrition Survey &#x0005b;<xref ref-type="bibr" rid="b1-kjim-2016-196">1</xref>&#x0005d;, the prevalence of COPD among subjects aged &#x02265; 40 years is 13.4% (19.4% of males, 7.9% of females). This is considerably higher than in other countries. COPD is a het&#x000ad;erogeneous disease &#x0005b;<xref ref-type="bibr" rid="b2-kjim-2016-196">2</xref>&#x0005d;, the prevalence of which is influenced by diverse fac&#x000ad;tors. Therefore, the high rate in Korea may have several explanations; these are outlined below.</p>
<p>First, Korea has a rate of cigarette smoking considerably higher than that of other countries. In 1995, the rate among Korean adult males was 66.7%. Although it has since decreased, it was 36.2% in 2013, which is the highest of all OECD (The Organisation for Econom&#x000ad;ic Co-operation and Development) countries &#x0005b;<xref ref-type="bibr" rid="b3-kjim-2016-196">3</xref>&#x0005d;. Second, a large number of Korean females have been exposed to biomass fuel in previous decades. Third, many in South Korea have tu&#x000ad;berculosis (Tb), which might be related to the high rate of COPD. According to data from The Latin American Project for the Investigation of Obstructive Lung Disease (PLATINO study) &#x0005b;<xref ref-type="bibr" rid="b4-kjim-2016-196">4</xref>&#x0005d;, a history of Tb is associated with airflow obstruction. Moreover, a study in Ko&#x000ad;rea &#x0005b;<xref ref-type="bibr" rid="b5-kjim-2016-196">5</xref>&#x0005d; reported that 76.8% of patients with Tb-destroyed lungs showed air&#x000ad;flow obstruction. Tb is also a risk factor for lung function impairment among Korean non-smokers &#x0005b;<xref ref-type="bibr" rid="b6-kjim-2016-196">6</xref>&#x0005d;.</p>
<p>The prevalence of COPD in North Korea is unclear due to a dearth of data. Furthermore, collection of such data is hampered by the restrictions placed on society in North Korea. However, its rate there is expected to be very high, because the three abovementioned risk factors for COPD are likely markedly more common there than in South Ko&#x000ad;rea. Indeed, Kim et al. &#x0005b;<xref ref-type="bibr" rid="b7-kjim-2016-196">7</xref>&#x0005d; reported that among 272 male North Korean defec&#x000ad;tors, 84.2% were current smokers and 12.5% were ex-smokers. Such a high rate of smoking will inevitably lead to a high prevalence of COPD. In addi&#x000ad;tion, North Korea is one of the poorest countries in the world and thus smoke inhalation from the burning of wood, charcoal, and other biomass is like&#x000ad;ly frequent. Furthermore, the country has an extremely high rate of Tb: at 345 cases out of every 100,000 people, it is higher than that in some countries with an epidemic of generalized human im&#x000ad;munodeficiency virus &#x0005b;<xref ref-type="bibr" rid="b8-kjim-2016-196">8</xref>&#x0005d;. Moreover, the lack of advanced medical facilities and/or anti-Tb medication and the high prevalence of multidrug-resistant Tb in North Korea suggest a high rate of Tb-destroyed lungs.</p>
<p>The high rate of COPD in South Korea and probably considerably higher rate in North Korea represent a huge socioeconomic burden. Screening for early COPD should be performed and adequate treatment should be provided in South Korea. Regarding North Korea, considerable effort will be required post-unification to identify and manage individuals with COPD.</p>
</body>
<back>
<fn-group>
<fn fn-type="conflict"><p>No potential conflict of interest relevant to this article was reported.</p></fn>
</fn-group>
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