Journal of Rheumatic Diseases Vol. 21, No. 4, August, 2014 http://dx.doi.org/10.4078/jrd.2014.21.4.187 Original Article 한국어번역본 Assessment of SpondyloArthritis International Society-Health Index 에대한임상적유효성평가 최정호ㆍ정현주ㆍ오태렴ㆍ이승헌ㆍ진준ㆍ이정원ㆍ이경은ㆍ박동진ㆍ박용욱ㆍ이신석ㆍ김태종 전남대학교의과대학류마티스내과학교실 Study on Clinical Effectiveness of the Korean Version of Assessment of SpondyloArthritis International Society-Health Index Jung-Ho Choi, Hyun-Ju Jung, Tae-Ryom Oh, Seung-Hun Lee, Joon Jin, Jeong-Won Lee, Kyung-Eun Lee, Dong-Jin Park, Yong-Wook Park, Shin-Seok Lee, Tae-Jong Kim Department of Rheumatology, Chonnam National University Medical School, Gwangju, Korea Objective. To evaluate the validity of the Korean version of ASAS-HI in patients with spondyloarthritis in Korea. Methods. A total of 91 patients were enrolled. We evaluated the validity by calculating the correlation coefficients between the Korean version of ASAS-HI and other clinical parameters, including patient global assessment (PGA), spinal back pain score, Bath ankylosing spondylitis disease activity index (BASDAI), Bath ankylosing spondylitis functional index (BASFI), ankylosing spondylitis disease activity score (AS-DAS), work productivity and activity impairment (WPAI) number 5 and number 6, hospital Anxiety and Depression Scale (HADS), health Survey Short-Form 36 (SF-36), and EuroQol visual analogue scale (EQ-5D VAS). Using a Pearson correlation coefficient, the validity was assessed by making a comparison between the correlation of the ASAS HI and clinical parameters in all patients. Results. The Korean version of ASAS-HI score was correlated with PGA, spinal back pain score, BASDAI, BASFI, AS-DAS, WPAI number 5, WPAI number 6, HADS, and EQ-5D (r=0.331, 0.403, 0.638, 0.500, 0.595, 0.480, 0.573, 0.626, 0.497, p=0.002, <0.001, <0.001, <0.001, <0.001, <0.001, <0.001, and <0.001, respectively). Conclusion. In this study, the clinical effectiveness of the Korean version of ASAS-HI was proved by calculating the correlation with other clinical parameters. The Korean version of ASAS-HI can be used in clinical practice and research to assess the healthy state of spondyloarthritis patients in Korea. Key Words. Spondylitis, Ankylosing, Patient outcome assessment 서론척추관절염 (spondyloarthritis, SpA) 은천장관절염 (sacroiliitis) 및척추염 (spondylitis), 주로하지에나타나는비대칭적 인소수관절염 (oligoarthritis), 손발가락염 (dactylitis), 부착부염 (enthesitis) 등의임상적인특징을공유하는질환군을나타낸다. 이러한질환군은 human leukocyte antigen (HLA)-B27과 <Received:July 28, 2014, Revised (1st: August 22, 2014, 2nd: August 22, 2014), Accepted:August 22, 2014> Corresponding to:tae-jong Kim, Department of Rheumatology, Chonnam National University Medical School, 42, Jebong-ro, Dong-gu, Gwangju 501-757, Korea. E-mail:ktj1562@chonnam.ac.kr pissn: 2093-940X, eissn: 2233-4718 Copyright c 2014 by The Korean College of Rheumatology This is a Free Access article, which permits unrestricted non-commerical use, distribution, and reproduction in any medium, provided the original work is properly cited. 187
188 최정호외 연관이있는것으로알려져있다 (1). 강직성척추염은척추관절염의범주에포함되는질환으로천장관절 (sacroiliac joint) 의염증이특징적으로나타나며, 말초관절과눈, 피부, 심혈관계등관절외장기에도염증이나타날수있다 (2-4). 강직성척추염은연골하상아질화및인대골증식 (syndysmophyte) 형성이가장특징적이며, 이러한것들이진행하여척추의강직과척추체의융합을일으킬수있다. 통증, 뻣뻣함, 골성강직 (bony ankylosis) 은다양한정도의척추의움직임의제한과기능의제한을가져올수있으며 (5-8), 이러한기능장애에대한전반적인평가를위한도구가필요하다 (9). Assessment of SpondyloArthritis international Society Health index (ASAS HI) 는 International Classification of Functioning, Disability and Health (ICF) 에기반을두고척추관절염환자의건강정도를측정하기위해개발되었다 (10-12). 강직성척추염에대한 ICF core set는축성척추관절염환자의모든기능과장애에대한정보를빠짐없이찾아내는것에대한기본개념을제공해준다 (10,13). 간단히말해서, ASAS HI는 ICF core set의항목을강직성척추염과연관시켜만들어진항목풀을기반으로하였으며각항목은기존에만들어져이미축성척추관절염환자에게사용하고있는설문지나, ICF와연관이있는설문지항목에근원을두고있다. 항목중일부는구조적인일관성을위해수정하였다. 동시에, 환자모임에서강직성척추염환자들이최종버전에포함되어야할중요한항목이나, 기존에설문지에포함되어있지않은새로운항목을제안받아총 44가지범주내포함된 251가지최종항목풀에서항목수를줄이기위해두 international cross-sectional 연구를시행하였다. ASAS HI 최종버전은통증, 정서적기능, 수면, 성기능, 활동성, 자가돌봄, 사회생활과취업의범주로분류된 17개의양자택일질문형식의항목으로구성되어있고각나라의언어적, 문화적요건을고려하여이를각나라별로번역작업을시행하였으며, 한국어버전작업역시시행되었다 (14). 이연구의목적은한국어로번역한 ASAS-HI 설문지 (Appendix) 의국내환자들에대한임상적유효성을검증하는데있다. 대상및방법총 91명의환자 ( 강직성척추염 50명, 비방사선학적척추관절염 29명, 말초형척추관절염 12명 ) 를대상으로연구를시행하였다. 강직성척추염은 modified New York criteria에따라 (15), 비방사선학적척추관절염과말초형척추관절염은 ASAS classification criteria에따라분류기준을만족하는환자들을각각모집하였다 (13,16). 허리뼈 (lumbar vertebra) 나대퇴골에손상이있는환자나, 이전에골절병력이있는환자및뼈질환과연관이있는다른질환이있는환자는이연구에서제외하였다. 환자들의나이, 성별등인구학적인정보와증상발생에서부터진단까지의기간, 허리통증정도, 생물학적제제사용여부, C-반응단백 (C-reactive protein, CRP) 등질환과관계있는특징적인정보를수집하였다. 이와동시에임상적인평가를시행하였으며, 이는전반적인기능평가 (Patient s global assessment), 한국어버전 Korean Hospital Anxiety and Depression Scale (KHADS) ( 비출간자료 ), 한국어버전 Korean Bath ankylosing spondylitis disease activity index (KBASDAI) (17), 한국어버전 Korean Bath ankylosing spondylitis functional index (KBASFI) ( 비출간자료 ), 건강문제와관련된삶의질의측정지표인한국어버전 Korean EuroQol-5 Dimensions Visual analogue scale (KEQ-5D VAS) (18), 기능과삶의질을포함한건강상태평가지표인한국어버전 Korean Short Form health survey (KSF-36) ( 비출간자료 ), 허리통증, 조조강직의지속시간, 말초관절의통증및부종, CRP 수치를기반으로척추관절염의활성도를평가하는 Ankylosing spondylitis disease activity score (AS-DAS) (19), 한국어버전 Korean work productivity and activity impairment (KWPAI) 항목중에서건강문제로인해일을하는데지장을초래하는지여부에대한지표인 5번항목과, 일상생활에서건강문제로지장을받는지여부에대한지표인 6번항목을포함하고있다 (20). 통계분석측정결과는연속변수의경우평균 ± 표준편차로표시하였고측정값이비연속적인경우에는퍼센트 (%) 로제시하였다. 인구학적인요소와임상적인평가지표들과의상관관계에대한분석을위해서 Pearson 상관관계분석을시행하였고상관관계분석에서는상관계수 (correlation coefficient) 의분석을상관계수가 (±) 0.75 이상인경우를 매우좋은선형관계, (±) 0.5부터 (±) 0.75 사이인경우를 중등도이상의좋은선형관계, (±) 0.25부터 (±) 0.5 사이인경우를 양호한선형관계, (±) 0.25 이하인경우를 미약한선형관계 로해석하였다. 모든통계분석은 SPSS version 17 (SPSS, Chicago, IL) 을사용하여수행하였으며, p-value <0.05의값은통계적으로의미있는것으로간주하였다. 결과강직성척추염환자 50명, 비방사선학적척추관절염 29명, 말초형척추관절염 12명환자를대상으로연구를시행하였다 (Table 1). 나이는강직성척추염, 비방사선학적척추관절염, 말초형척추관절염에서각각 35.1±10.7세, 33.1±11.0세, 32.8±10.0세로각군간에큰차이를보이지않았으며, 남성의비율은각각 86.0%, 82.8%, 41.7% 로강직성척추염과, 비방사선학적척추관절염환자군에서상대적으로남성의비율이더높았다. 증상발생으로부터진단받을때까지의기간은강직성척추염환자군에서 9.7±6.2년으로가장길었으며, 비방사선학적척추관절염, 말초형척추관절염환자군에서는각각 4.3±3.2, 3.9±2.4년으로강직성척추염환자들에비해상대적으로그기간이짧았다. 염증표지자인 CRP는
Clinical Effectiveness of the Korean Version of ASAS-HI 189 비방사선학적척추관절염환자군에서가장낮은수치를보였다. 그러나통증정도및염증표지자수치와관계가있을것으로생각되는질환의활성도평가지표인 KBASDAI, AS-DAS는세군간에큰차이를보이지않았으며, 환자가느끼는질환의활성도역시비슷한수준을보였다. 기능적인측면에대한정보를제공하여주는 KBASFI는비방사선학적척추관절염에서 0.5±0.6으로가장낮은수치를보였지만, 나머지두군에서도비교적낮은수치를보여전반적으로기능적인제한은크지않은것으로보였다. 삶의질과관련이있는지표인 KEQ-5D, KSF-36은세군간에큰차이를보이지않았다. 환자의불안과우울감에대한척도로 KHADS를측정하였으며, 세군모두불안감이나우울감은심하지않은것으로보였다. ASAS-HI 한국어버전은강직성척추염, 비방사선학적척추관절염, 말초형관절염에서각각 4.5±3.4, 3.6±2.7, 4.3±3.0으로세군간에큰차이를보이지않았다. 생물학제제사용여부에서는강직성척추염환자군과말초형척추관절염환자군에서각각 77.6%, 81.8% 로사용빈도가높았으며, 비방사선학적척추관절염환자군에서는 39.3% 로다른두군에비해서사용빈도가상대적으로낮았다 (Table 1). ASAS-HI 한국어버전의유효성검증 (validation) 을위해질환에대한다른임상적인평가와삶의질과관련된지표들을비교하였다 (Table 2). ASAS-HI 한국어버전은척추관절염의임상적인평가에흔히사용하고있는 KBASDAI, KBASFI, AS-DAS, KWPAI 설문지중일상생활에지장을초래하는지여부에관한항목인 6번항목과중등도이상의좋은선형상관관계를보였으며 (r=0.638, 0.500, 0.595, 0.573; p<0.001, <0.001, <0.001, <0.001), patient s global assessment, 허리통증, KWPAI 중일하는데지장을초래하는지여부에관한항목인 5번항목과는양호한선형상관관계를보 였다 (r=0.331, 0.403, 0.480; p=0.002, <0.001, <0.001). 삶의 Table 2. Correlation coefficient between ASAS-HI score and other clinical factors Factors Age (years) Disease duration (years) Patient s global assessment (0-10 NRS) Education Disease activity (0-10 NRS) Spinal back pain (0-10 NRS) KBASDAI (scores) KBASFI (scores) CRP (mg/l) AS-DAS (scores) KWPAI, while working (scores) KWPAI, regular activity (scores) KHADS (scores) KSF-36 (scores) KEQ-5D VAS (mm) Pearson correlation coefficients ASAS-HI (scores) 0.225* 0.165 0.331 0.005* 0.209 0.403 0.638 0.500 0.152 0.595 0.480 0.573 0.626 0.209* 0.497 ASAS-HI: ASAS heath index, KBASDAI: Korean Bath ankylosing spondylitis disease activity index, KBASFI: Korean Bath ankylosing spondylitis functional index, CRP: C-reactive protein, AS-DAS: Ankylosing spondylitis disease activity score, KWPAI: Korean work productivity and activity impairment, KHADS: Korean Hospital Anxiety and Depression Scale, KSF-36: Korean Health Survey Short-Form 36, KEQ-5D: Korean EuroQol visual analogue scale, *p<0.05, <0.01. Table 1. Baseline demographics and clinical characteristics of subjects AS (n=50) Nr-axial SpA (n=29) Peripheral SpA (n=12) Age (years) (mean±sd) Male, No. (total, %) Symptom duration (years) (mean±sd) PGA (0-10 NRS) (mean±sd) Disease activity (0-10 NRS) (mean±sd) Spinal back pain (0-10 NRS) (mean±sd) KHADS (mean±sd) KBASDAI (mean±sd) KBASFI (mean±sd) KEQ-5D VAS (mean±sd) KSF-36 (mean±sd) CRP (mg/l) (mean±sd) AS-DAS (mean±sd) Biologics use, No. (%) ASAS-HI (mean±sd) 35.1±10.7 43 (86.0) 9.7±6.2 3.4±1.7 3.9±2.3 2.9±2.3 10.9±7.1 3.7±2.3 1.2±1.7 69.3±20.0 101.12±8.3 3.8±6.5 1.8±1.1 38 (77.6) 4.5±3.4 33.1±11.0 24 (82.8) 4.3±3.2 3.1±1.6 3.6±2.5 3.5±2.3 9.0±4.2 3.4±2.1 0.5±0.6 71.7±18.1 98.6±21.2 1.8±2.1 1.6±1.1 11 (39.3) 3.64±2.7 32.8±10.0 5 (41.7) 3.9±2.4 3.0±1.9 3.9±2.3 1.6±1.6 11.3±3.7 3.9±2.1 1.4±2.0 65.4±15.3 105.4±6.8 4.2±6.4 1.8±1.1 9 (81.8) 4.3±3.0 AS: Ankylosing spondylitis, Nr-axial SpA: non-radiographics axial spondyloarthritis, Peripheral SpA: Peripheral spondyloarthritis, PGA: patient s global assessment, KHADS: Korean hospital Anxiety and Depression Scale, KBASDAI: Korean Bath ankylosing spondylitis disease activity index, KBASFI: Korean Bath ankylosing spondylitis functional index, KEQ-5D: Korean EuroQol visual analogue scale, KSF-36: Korean Health Survey Short-Form 36, CRP: C-reactive protein, AS-DAS: Ankylosing spondylitis disease activity score, ASAS-HI: ASAS heath index.
190 최정호외 Table 3. Differences in ASAS-HI between the gender or the use of biologics Sex (mean±sd) Male Female Biologics (mean±sd) Use Never ASAS-HI: ASAS heath index. Number ASAS-HI p-value 70 19 57 30 3.9±3.2 5.0±2.9 4.3±3.2 3.9±3.1 0.197 0.616 질과관련된지표인 KSF-36과는약한음의상관관계를보였으며, KEQ-5D VAS는양호한음의선형상관관계를보였다 (r= 0.209, 0.497; p=0.05. <0.001). 그이외에나이도약한상관관계를보였다 (r=0.225, p=0.034). 증상발생부터진단까지의기간, CRP는 ASAS-HI 한국어버전과통계학적으로유의한상관관계를보이지않았다 (p 0.05). 환자의성별과, 생물학적제제사용유무에따라 ASAS-HI 한국어버전의차이를분석해보았을때, 남녀각각 ASAS-HI는 3.9±3.2, 5.0±2.9로성별에따른차이는저명하지않았으며 (p=0.197), 생물학적제제사용유무에따른차이에대한분석에서도두군간에유의한차이를보이지않았다 (p=0.616)(table 3). 고찰척추관절염은환자들의삶에상당한영향을미치고있다. 그러나전문가들사이에서질병활성도및심각성평가에대한의견일치가이루어지지않아건강정도를양적으로측정할수있는기준이나도구의필요성이대두되었다. 이러한배경으로건강과기능및장애에대한국제분류인 ICF에기반을두고, 12개국의 19명의전문가들이모여 Comprehensive ICF Core Set과 Brief ICF Core Set를정의하였으며 (10), 다시이를기반으로해서총 17개의항목으로구성된 ASAS-HI를개발하였다 (21). 최근 ASAS-HI 한국어번역중시행한유효성예비검증에서 Spinal pain, PGA, BASDAI, BASFI, BASMI (Bath ankylosing spondylitis metrology index), EQ VAS과상관관계를확인함으로써 ASAS-HI 한국어버전에대한기본적인유효성검증을시행한바있다 (14). 하지만본연구에서는이전연구보다더많은환자를포함시켰으며, 이전연구에서는포함하지않았던질병과관련된여러가지임상지표들을포함시킴으로써유효성검증의질을높이고자하였다. 총 91명을대상으로분석을시행한이번연구에서 ASAS- HI 한국어버전은 patient s global assessment, 허리통증정도, KBASDAI, KBASFI, KWPAI 항목 5번과 6번, AS-DAS, KEQ-5D VAS와유의한상관관계를가지는것으로나타났다. 이는이전에시행하였던연구와거의동일한결과로 ASAS-HI 한국어버전의임상적인유효성을재증명하는근거라고할수있다. 기존의연구에는포함되지않았던임상지표들인 AS-DAS, KWPAI 항목 5번과 6번, KHADS, KSF-36를이번연구에서는추가적으로포함시켰다. AS-DAS는환자가느끼는허리통증, 조조강직의지속시간, patient s global assessment, 말초관절의통증및부종, CRP 또는 ESR을변수로가지고이를기반으로질병활성도에대한평가를하는지표로서, AS환자를대상으로질병활성도평가측면에대해 BASDAI와비교한연구에서 BASDAI와 AS-DAS는비슷한수준의결과를보였으며, CRP나 ESR과같은염증수치가상승되어있는세부그룹분석에서는 BASDAI 보다질병활성도평가측면에있어서더우수하다는연구결과가있다 (22). 이번연구결과 ASAS-HI 한국어버전은 AS-DAS, KBASDAI와의상관관계분석에서두가지임상지표들과모두중등도이상의좋은상관관계를보였으며, 이러한결과는 ASAS-HI 한국어버전이질병활성도평가측면에있어서유용한평가도구로사용될수있음을시사한다고할수있다. WPAI 항목 5번 6번은직장생활및일상생활에서질환이미치는영향을반영하는지표로역시 ASAS-HI 한국어버전과좋은상관관계를보였으며, 우울감에대한평가지표인 KHADS 역시중등도이상의좋은상관관계를보였다. 이는 ASAS-HI가단순한기능평가를넘어서직장생활과일상생활을포함한사회경제적인측면및정서적인측면을간접적으로반영하고있음을나타내는증거라고생각된다. ASAS-HI 한국어버전이기존의다른지표들과구분되는또하나의특징은 KEQ-5D VAS, KSF-36과같은삶의질적인측면을반영하는지표와도좋은상관관계를보이는점이다. BASDAI, BASFI, AS-DAS와같이질병의활성도나기능적인측면에대한평가뿐만아니라삶의질을반영하고있다는점은다른임상지표들과비교되는 ASAS-HI 한국어버전의장점이라고할수있다. 결론 ASAS-HI 한국어버전은척추관절염환자의질병활성도및기능에대한평가등임상적인측면뿐만아니라, 삶의질적인측면도반영하고있으며, 간접적으로사회경제적인측면및정서적인측면까지반영하고있는환자평가도구로이에대한유효성이검증되었으며, 향후척추관절염환자에관한임상연구및진료에유용하게사용될수있을것이라고생각한다. 감사의글본논문은전남대학교병원의생명연구원의지원을받아수행된연구입니다 ( 과제고유번호 : CRI 14010-1). References 1. Healy PJ, Helliwell PS. Classification of the spondyloarthropathies. Curr Opin Rheumatol 2005;17:395-9. 2. Khan MA, van der Linden SM. A wider spectrum of spondyloarthropathies. Semin Arthritis Rheum 1990;20: 107-13.
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