폐활량측정법의새로운정상예측식이폐활량측정법장애양상및질병중증도해석에미치는영향 울산대학교의과대학서울아산병원호흡기내과, 만성기도폐쇄성질환임상연구센터, 연세대학교의과대학내과학교실 오연목, 홍상범, 심태선, 임채만, 고윤석, 김우성, 김동순, 김원동, 김영삼, 이상도 Effect of a New Spirometric Reference Equation on the Interpretation of Spirometric Patterns and Disease Severity Yeon-Mok Oh, M.D., Sang-Bum Hong, M.D., Tae Sun Shim, M.D., Chae-Man Lim, M.D., Younsuck Koh, M.D., Woo Sung Kim, M.D., Dong-Soon Kim, M.D., Won Dong Kim, M.D., Young Sam Kim, M.D., Sang Do Lee, M.D Department of Internal Medicine and Clinical Research Center for Chronic Obstructive Airway Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea Background : A spirometric reference equation was recently developed for the general population in Korea. The applicability of the new Korean equation to clinical practice was examined by comparing it with the Morris equation, which is one of the most popular reference equations used for interpreting the spirometric patterns and for grading the disease severity in Korea. Methods : Spirometry was performed on 92 men and 94 women, aged 20 years or older, in November 2004 at the Asan Medical Center, Seoul, Korea. The subjects age, gender, height, weight, and spirometric values (FEV [forced expiratory volume in one second], FVC [forced vital capacity], and FEV /FVC) were obtained. The spirometric patterns and disease severity were evaluated using both equations, and the results of the Korean equation were compared with the Morris equation. The spirometric patterns were defined as normal, restrictive, obstructive, and undetermined according to the level of FEV /FVC and FVC. The disease severity was defined according to the level of FEV level for subjects with an airflow limitation, and according to the FVC level for those subjects without an airflow limitation. Results : Spirometric patterns were differently interpreted in 22.5% (208/92) of the men and 24.8% (72/94) of the women after the application of the Korean equation compared with the Morris equation. Of the subjects with airflow limitation, disease severity was differently graded in 30.2% (4/378) of the men and 39.4% (37/94) of the women after the application of the Korean equation. Of the subjects without airflow limitation, disease severity was differently graded in 27.9% (53/548) of the men and 30.2% (8/00) of the women after the application of the Korean equation. Conclusion : Achange in the reference equation for spirometry could have an effect on the interpretation of spirometric patterns and on the grading of disease severity. (Tuberc Respir Dis 200; 0: 25-220) Key words : Spirometry; reference equation; interpretation. 서 폐활량측정법 (spirometry) 은호흡기질병을평가하는데중요한진단적검사중하나이다. 폐활량측정 Address for correspondence : Sang Do Lee, M.D. Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine and Clinical Research Center for Chronic Obstructive Airway Diseases, Asan Medical Center, University of Ulsan College of Medicine, 388- Pungnap-dong, Sonpa-gu, Seoul 38-73, South Korea Phone : 02-300-340 Fax : 02-300-98 E-mail : sdlee@amc.seoul.kr Received : Jan. 2. 200 Accepted : Feb. 2. 200 론 법으로질병을확정적으로정확히진단할수있는것은아니지만폐활량측정법결과를올바르게해석하면폐쇄성질환인지아니면제한성질환인지감별해낼수있고질병의중증도를평가하는데도움을줄수있다. 폐활량측정법결과를해석하고질병중증도를평가하려면정상인을대상으로한폐활량측정법의정상예측식이필요하다 2. 폐활량측정법의정상예측식은여러나라에서개발되어사용하고있으며사용하는정상예측식이달라지면그에따라폐활량측정법결과를해석하는것과질병의중증도를평가하는것이달라질수있다. 하지만, 정상예측식이달라지면그에따라폐활량측정법결과를해석하는것과 25
SD Lee et al. : Effect of a new spirometric reference equation 질병의중증도를평가하는것이실제환자를진료할때얼마나영향을주는지정량적으로평가한연구는아직없는것같다. 최근우리나라의전체인구집단을대상으로폐활량측정법정상예측식이개발되었다 3. 우리의정상예측식이개발되기전까지는다른나라의정상예측식을차용하여사용하고있었으며그중많이사용하던정상예측식은 Morris 예측식으로서미국인을대상으로개발한정상예측식이다 4. 이제한국인의정상예측식을실제환자진료에적용하기전에정상예측식이 Morris 예측식에서한국인정상예측식으로바꾸어사용함으로써폐활량측정법해석결과가어떻게달라지는지그리고질병의중증도평가가어떻게달라지는지알아보고자본연구를구상하게되었다. 대상및방법. 대상 20세이상성인중서울아산병원의호흡기검사실에서 2004년도 월한달간폐활량측정법을시행한남자 92명과여자 94명을대상으로하였다. 이대상환자들이폐활량측정법을시행하게된주요이유는호흡기질환을평가하거나아니면수술전폐기능을평가하기위해서였다. 2. 방법 ) 폐활량측정법폐활량측정기 (Vmax22 or 230, SensorMedics, 미국 ) 를사용하여 초간노력성호기량 (forced expiratory volume in one second, FEV ), 노력성폐활량 (forced vital capacity, FVC), 그리고 FEV /FVC를구하였다. 폐활량측정법은미국흉부학회에서권장하는방법으로시행하였다 5. 폐활량측정법정상예측식으로 Morris식과한국인정상예측식을사용하여비교하였다 (Table ) 3,4. 2) 폐활량측정법장애양상및질병중증도정의정상폐활량측정법은 FEV /FVC 0.7 그리고 FVC 80% 예측치로정의하였다. 제한성장애 (restrictive pattern) 는 FEV /FVC 0.7 그리고 FVC <80% 예측치로정의하였다. 폐쇄성장애 (obstructive pattern) 는 FEV /FVC <0.7 그리고 FVC 80% 예측치로정의하였다. 양상미정 (undetermined pattern) 은 FEV /FVC <0.7 그리고 FVC <80% 예측치로정의하였다. 대상환자가기류폐쇄가있는경우 (FEV /FVC <0.7), 질병의중증도를 FEV (% 예측치 ) 80%, <80% 그리고 50%, <50% 그리고 30%, <30% 대해서각각경증 (mild), 중등증 (moderate), Table. Reference equations 3,4 Morris equation FEV FVC Korean equation FEV Males Ht* x 0.092 x 0.3937 - Age x 0.032 -.20 Females Ht x 0.089 x 0.3937 - Age x 0.025 -.932 Males Ht x 0.48 x 0.3937 - Age x 0.025-4.24 Females Ht x 0.5 x 0.3937 - Age x 0.024-2.852 Males 0.04578 x Ht - 0.0002484 x Age2-3.432 Females 0.03558 x Ht - 0.000920 x Age2-2.44 Males 0.05292 x Ht + 0.00947 x Wt - 0.0000833 xage2-4.8434 FVC Females 0.0395 x Ht + 0.00892 x Wt -0.0002728 x Age2-3.000 *Height in centimeters; a conversion factor from inches to centimeters; Age in years; Weight in kilograms 2
Tuberculosis and Respiratory Diseases Vol. 0. No. 2, Feb. 200 Table 2. Characteristics of the subjects Men Women Number 92 94 Age (years) 0.0 ± 3.2* 58.4± 2. Height (cm) 7 ±. 54 ± 5.8 Weight (kg) 5.8 ± 0. 57. ± 8.4 FEV (L) 2.35 ± 0.83.88 ± 0.55 FVC (L) 3.34 ± 0.82 2.37 ± 0.58 FEV/FVC 0.70 ± 0.5 0.79 ± 0.0 * mean ± standard deviation 중증 (severe), 최중증 (very severe) 으로정의하였다. 대상환자가기류폐쇄가없는경우 (FEV /FVC 0.7), 질병의중증도를 FVC (% 예측치 ) <80% 그리고 0%, <0% 그리고 >50%, 50% 대해서각각경증 (mild), 중등증 (moderate), 중증 (severe) 으로정의하였다 7. 3) 통계분석카이제곱검정을이용하여폐활량측정법장애양상과질병중증도를비교하였다. P 값이 0.05보다작은경우유의하게차이가난다고결론지었다. 통계프로그램으로 SPSS (0.판) 을사용하여통계분석을시행하였다. 결과. 대상환자특성대상환자의평균연령은 59.3세이었다. 대상환자 20명중 92명은남자이고 94명은여자이었다. (T able 2). Figure. Effect of different reference equations on the interpretation of spirometric patterns. Spirometric patterns were differently interpreted after the change in reference equation from the Morris to the new Korean equation (P<0.00 in both males and females by the chi-square test). Definition: normal pattern, FE- V /FVC 0.7 & FVC 80% predicted value; restrictive pattern, FEV /FVC 0.7 & FVC <80% predicted value; obstructive pattern, FEV /FVC <0.7 & FVC 80% predicted value; undetermined pattern, FEV /FVC <0.7 &FVC <80% predicted value. The number inside each block represents the number of subjects showing each spirometric pattern. 사용하였을때, 정상에서제한성장애로해석이달라지는경우와폐쇄성장애에서양상미정으로해석이달라지는경우가연령이증가함에따라더많아지는경향을보였다 (P=0.02) (Table 3). 정상예측식으로 Morris 식대신한국인예측식을사용하였을때, 제한성장애에서정상으로해석이달라지는경우와양상미정에서폐쇄성장애로해석이달라지는경우는남자의 20대에서만관찰되었다. 2. 폐활량측정법장애양상 (spirometric patterns) 3. 질병중증도 (Ddisease severity) 폐활량측정법을해석할때정상예측식으로 Morris 식대신한국인예측식을사용하면, 남자 92명중 208 명 (22.5%) 과여자 94명중 72명 (24.8%) 에서폐활량측정법장애양상해석이달라지게되었다 (Figure & Table 3). 정상예측식으로 Morris식대신한국인예측식을 ) 기류폐쇄가있는경우폐활량측정법을해석할때정상예측식으로 Morris 식대신한국인예측식을사용하면, 기류폐쇄 (FEV / FVC <0.7) 를보이는남자 378명중 4명 (30.2%) 에서질병중증도평가가달라지게되었다 (Figure 2). 비슷한결과가기류폐쇄를보이는여자 94명에게서 27
SD Lee et al. : Effect of a new spirometric reference equation Table 3. Number of subjects showing spirometric pattern shift in each age group by the change in reference equations from the Morris to the Korean equation 3,4 A. Men Age group (years) Pattern shift* MenAll ages 20-29 30-39 40-49 50-59 0-9 70-79 80 Normal to restrictive 0 Restrictive to normal Obstructive to undetermined Undetermined to obstructive Total number of subjects in each age group (4.0) (3.0) 0 0 (2.3) 5 (5.8) 29 (3.4) 54 (.5) 29 (5.5) 3 (9.4) 0 0 0 0 0 0 2 (2.3) (5.) 37 (.3) 23 (2.3) 7 (2.9) 0 0 0 0 0 0 2 (3.2) (3.%) (0.7) (0.7%) 80 (8.80) (8.%) (0.) 43 33 8 27 328 87 32 92 (0.%) B. Women Pattern shift* Age group (years) 20-29 30-39 40-49 50-59 0-9 70-79 80 All ages Normal to restrictive 0 0 4 33 8 38 2 45 (4.3) (8.9) (28.7) (3.4) (20.0) (20.9) Restrictive to normal 0 0 0 0 0 0 0 0 Obstructive to 4 9 3.9 0 undetermined (2.7) (4.3) (3.4) (2.5) (7.4) (0.0) (27) Undetermined to obstructive 0 0 0 0 0 0 0 0 Total number of subjects in each age group 20 37 94 75 237 2 0 94 *No other types of the pattern shift were observed other than the above four types. The numbers in parentheses represent the percentage of subjects showing each pattern shift among each age group. 도관찰되어 37명 (39.4%) 의중증도가달라지게되었다. 질병의중증도가달라지게된모든환자에서 Morris 식대신한국인예측식을사용하면중증도가더나쁜것처럼분류되었다. 2) 기류폐쇄가없는경우폐활량측정법을해석할때정상예측식으로 Morris 식대신한국인예측식을사용하면, 기류폐쇄가없는 (FEV/FVC 0.7) 남자 548 명중 53명 (27.9%) 에서질병중증도평가가달라지게되었다 (Figure 3). 비슷한결과가기류폐쇄가없는여자 00명에게서도관찰되어 8명 (30.2%) 의중증도가달라지게되었다. 질병의중증도가달라지게된대다수환자에서 Morris 식대신한국인예측식을사용하면중증도가더나쁜것처럼분류되었다. 단지, 7명의환자만한국인예측식을사용하면중증도가더좋아진것처럼분류되었다. 고찰본연구를통해서폐활량측정법정상예측식을외국의 Morris 예측식 4 에서한국인예측식 3 으로바꾸어사용하면폐활량측정법양상과중증도해석에유의한영향을미침을확인할수있었다. 예측식을 Morris식에서한국인예측식으로바꾸게되면 20% 가넘는환자의폐활량측정법장애양상해석이달라지게되었으며약 30% 환자에서는질병의중증도분류가달라지게되었다. 한국인예측식으로바꾸어사용할때폐활량측정법양상변화는주로 정상 에서 제한성장애 이었다. 또한, 한국인예측식으로바꾸어사용하면대다수의환자에서질병의중증도가더나빠진것처럼해석되었다. 이같은연구결과는최등이한국인예측식을개발하였을때 Morris 예측식과비교하면서어느정도예상할수있었는데폐활량측 28
Tuberculosis and Respiratory Diseases Vol. 0. No. 2, Feb. 200 Figure 2. Effect of different reference equations on disease severity in subjects with airflow limitation (FEV /FVC <0.7). Disease severity was differently interpreted after the change in reference equation from the Morris to the new Korean equation (P<0.00 in both males and females by the chi-square test). Disease se verity was defined as mild, moderate, severe, and very severe according to FEV (% predicted value) of 80%, <80% & 50%, <50% & 30%, and <30%, respectively. The number inside each block represents the number of subjects showing each grade of disease severity. 정법의예측치 (FEV 과 FVC) 들이우리나라정상인이미국의정상인보다더크게나왔기때문이다 3. 최등은 Morris 식과한국인예측식으로부터얻어지는 FVC값의차이가남자는.3% 이었고여자는 2.5% 이었다고보고하였다. 또한, 두예측식에서얻어지는 FEV, 값차이가남자는 7.% 이었고여자는 0.2% 이었다고보고하였다. 하지만, 우리의연구결과에의하면한국인예측식을실제진료에사용하게되었을때는최등이보고한차이보다더큰차이가폐활량측정법을해석하는데나타날수있음을보여주었다. 본저자들이아는한에서는본연구는폐활량측정법정상예측식을다른예측식으로사용하였을때폐활량측정법장애양상해석과질병중증도평가에어떻게영향을미치는지정량적으로평가한첫보고이다. 폐활량측정법의정상예측식은나라와인종마다차이가난다. 한국인예측식이개발되기전까지우리는다른나라에서개발한예측식을사용하였고그중 Morris 예측식은가장많이차용하여사용하던예측식중하나이었다. Figure 3. Effect of different reference equations on disease severity in subjects without airflow limitation (FEV /FVC 0.7). Disease severity was differently interpreted after the change in reference equation from the Morris to the new Korean equation (P<0.00 in both males and females, by the chi-square test). Disease severity was defined as mild, moderate, and severe according to FVC (% predicted value) of <80% & 0%, <0% & >50%, and 50%, respectively. The number inside each block represents the number of subjects showing each grade of disease severity. 본연구에서사용한폐활량측정법장애양상정의와질병중증도정의는다소임의적이었다. 본연구에서폐쇄성장애의정의는 FEV /FVC <0.7 그리고 FVC 80% 예측치 로하였다. 비록 95 백분위수방법이나 95% 신뢰구간방법으로장애여부를정의하는것이이상적이기는하지만만성폐쇄성폐질환 (chronic obstructive pulmonary disease, COPD) 에대한지침서에는폐쇄성장애진단을편리한방법인 FEV /FVC <0.7 를사용하였고, -8 본연구에서도이방법을사용하였다. 본연구에서양상미정 (undetermined pattern) 을보인환자의다수는폐쇄성장애일가능성이높지만 9, 추가로임상정보나방사선정보를더분석하지는않았다. 본연구에서사용한질병중증도분류는기류폐쇄가있는경우는 COPD 국제지침의분류를따랐으며기류폐쇄가없는경우는미국의사회에서호흡기장애분류에사용하는중증도분류법을따랐다,7. 본연구의제한점으로는폐활량측정법외의다른임상정보나방사선정보를더평가하지는않았기때 29
SD Lee et al. : Effect of a new spirometric reference equation 문에새로사용하게되는한국인예측식이실제폐활량측정법장애양상해석및질병중증도평가에더우월한지확인할수없었다. 그렇지만, 본연구를통해서한국인예측식을사용하게되면폐활량측정법해석이상당히바뀌게됨을알수있게되었다. 결론적으로, 폐활량측정법정상예측식을바꾸어사용하게될경우장애양상해석과질병중증도평가에유의한영향을미칠수있으므로새로운한국인예측식을적용하여진료를할때이점을유념하여진료하는것이필요하겠다. 요약 (4/378) 바뀌었고여자에서 39.4% (37/94) 바뀌었다. 기류제한이없는환자의경우는질병의중증도가남자에서 27.9% (53/548) 바뀌었고여자에서 30.2% (8/00) 바뀌었다. 결론 : 폐활량측정법정상예측식이바뀌면장애양상해석과질병중증도평가에유의한영향을미칠수있다. 감사의글본연구는보건복지부보건의료기술진흥사업의지원에의하여이루어진것임 (042-CR03-0704-000) 연구배경 : 폐활량측정법정상예측식이한국인을대상으로개발되었다. 한국인정상예측식을실제진료에사용하기위해서그동안많이사용하던정상예측식중하나인 Morris 예측식을적용하였을때와한국인예측식을적용하였을때장애양상해석및질병중증도평가가어떻게달라지나비교하고자하였다. 방법 : 서울아산병원의호흡기검사실에서 2004년도 월한달간폐활량측정법을시행한남자 92명과여자 94명을대상으로하였다. 나이, 성, 키, 몸무게, 그리고폐활량측정법으로 FEV [forced expiratory volume in one second], FVC [forced vital capacity], FEV /FVC 등을구하였다. 한국인예측식과 Morris 예측식을사용하여장애양상해석과질병중증도평가를하였고그차이를비교하였다. 폐활량측정법장애양상은 FEV /FVC과 FVC 값에따라서정상, 제한성, 폐쇄성, 양상미정등으로정의하였고질병중증도는기류제한이있는환자는 FEV 값에따라서기류제한이없는환자는 FVC값에따라서정의하였다. 결과 : Morris 예측식에서한국인예측식으로바꾸어적용하면장애양상해석이남자환자의경우 22.5% (208/92) 달라졌고여자의경우 24.8% (72/94) 달라졌다. 한국인예측식을적용하였을때, 기류제한이있는환자의경우질병의중증도가남자에서 30.2% 참고문헌. Gold WM. Pulmonary function testing. In: Murray JF, Nadel JA, editors. Textbook of respiratory medicine. 3rd ed. W.B. Philadelphia: Saunders; 2000. p. 78-88. 2. American Thoracic Society. Lung function testing: selection of reference values and interpretative strategies. Am Rev Respir Dis 99;44:202-8. 3. Choi JK, Paek D, Lee JO. Normal predictive values of spirometry for Korean population. Tuberc Respir Dis 2005;58:230-42. 4. Morris JF, Koski A, Johnson LC. Spirometric standards for healthy nonsmoking adults. Am Rev Respir Dis 97;03:57-7. 5. American Thoracic Society. Standardization of Spirometry: 994 update. Am J Respir Crit Care Med 99 5;52:07-3.. National Heart, Lung, and Blood Institute and World Health Organization. Global initiative for chronic obstructive lung disease: global strategy for the diagnosis, management, and prevention of chronic obstructive pulmonary disease. National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA [revised 2003; cited 20 August 2004]. Available from: URL: http:// www.goldcopd.com 7. American Medical Association. Guides to the evaluation of permanent impairment. 4th ed. Chicago: American Medical Association 993. 8. American Thoracic Society and European Respiratory Society. Standards for the diagnosis and treatment of patients with chronic obstructive pulmonary disease. American Thoracic Society, New York, USA [cited 0 June 2-004]. Available from URL: http://www.thoracic.org/copd/ 9. Dykstra BJ, Scanlon PD, Kester MM, Beck KC, Enright PL. Lung volumes in 4,774 patients with obstructive lung disease. Chest 999;5:8-74. 220