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1 대한내과학회지 : 제 86 권제 4 호 특집 (Special Review) - 비알코올지방간질환 비알코올지방간질환의생활습관치료 한양대학교의과대학내과학교실 유기덕 전대원 Nonalcoholic Fatty Liver Disease: Lifestyle Modification Ki Deok Yoo and Dae Won Jun Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea Non-alcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease. The prevalence of NAFLD is growing gradually worldwide with increases in obesity, sedentary lifestyles, and an unbalanced diet. NAFLD ranges from simple steatosis without inflammation to steatohepatitis that can progress to cirrhosis. There is no single effective treatment that has widespread effects in NAFLD. The cornerstone of treatment is lifestyle modification, including weight reduction, diet, and physical activity. An approximately 7-10% weight reduction via diet or physical activity can improve the liver histopathology. Risk factors for NAFLD include a high-calorie diet, high-lipid diet, high-carbohydrate diet, saturated fatty acids, trans fatty acids, cholesterol, high fructose intake, and low-choline diet. Factors that protect against NAFLD include a low-calorie diet, low-carbohydrate diet, low-lipid diet, monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), dietary fiber, coffee, green tea, and light alcohol consumption. Physical activity also helps to manage NAFLD with or without weight reduction. Recent reports found that resistance training is as effective as aerobic training. Lifestyle modification has very low compliance. To maintain a treatment program, a multidisciplinary team approach is required that includes physicians, dietitians, physical trainers, and psychologists. (Korean J Med 2014;86: ) Keywords: Non-alcoholic fatty liver disease; Lifestyle modification; Treatment 서론비알코올지방간질환 (non-alcoholic fatty liver disease) 은간에과다한지방이침착되는질환이다. 비알코올지방간은이전에는인슐린저항성및대사증후군의하나의표현형으로생각되어왔으나최근비알코올지방간이심혈관계질환, 당뇨, 고혈압및신장질환발생에있어독립적인위험인자로 밝혀지면서그임상적중요성이증가하고있다 [1]. 의미있는알코올섭취의기준은연구마다다양하게정의되지만최근이탈리아, 미국간학회가이드라인및대한간학회진료지침에서유의한알코올의섭취량을최근 2년동안남자는주당 21 잔, 여자는주당 14잔을초과하는경우로정의하였다 [2-4]. 비알코올지방간질환의발생은비만, 그중에서도복부비만과매우밀접한관계를가지는것으로알려져있다. 비만 Correspondence to Dae Won Jun, M.D. Department of Internal Medicine, Hanyang University College of Medicine, 222 Wangsimni-ro, Seongdong-gu, Seoul , Korea Tel: , Fax: , noshin@hanyang.ac.kr Copyright c 2014 The Korean Association of Internal Medicine This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

2 - Ki Deok Yoo, et al. NAFLD: Lifestyle modification - 인구가증가함에따라최근우리나라에서비알코올성지방간환자가증가하고있다. 우리나라의비알코올지방간질환에연관된자료는대부분건강검진대상자를대상으로얻어진자료로실제인구집단을대상으로한비알코올지방간유병률과는차이가있을수있지만서양의유병률이크게다르지않을것이라는것이일반적인견해이다. 주목할점은비알코올지방간질환자의 20-40% 는정상체중이며 [5,6] 특히동양인이서양인에비해낮은체질량지수를보임에도지방간질환의유병률은비슷하다는점이다. 이처럼동양인의경우서양인과비교하여낮은체질량지수에서비알코올성지방간의높은유병률에대한여러가지해석들이있으나유전적인요인과함께동 서양간식이행동의차이가중요한요인으로제시되고있다 [7,8]. 전통적으로비알코올지방간의발생원인으로과다한지방의섭취가중요한원인으로지목받고있다. 그러나대부분의선행연구들은서양중심의식이요인에대한분석을통해제시된것이며우리나라의식이가에너지영양소구성비율, 지방산구성비율, 주요영양소급원식품등다양한면에서서양과다른점을고려할때, 서양중심의선행연구결과를해석할때주의하여야할점이있다. 우리나라의경우쌀을주식으로하여탄수화물의섭취가많아탄수화물의과잉섭취가비만, 대사질환및비알코올지방간질환의발생에중요한역할을할것으로주목받고있다. 최근지방산과콜레스테롤이외에탄수화물섭취의비만및간내지방합성의역할에대하여활발한연구가진행되고있다. 본고에서는비알코올지방간질환의치료중에서생활습관의개선, 그중에서대표적인체중감량, 식이요법, 운동요법에대해서알아보고자한다. 생활습관의변화 (lifestyle modification) 를통한체중감소비알코올지방간환자의대부분이과체중이거나비만하며인슐린저항성및심혈관질환위험도를가지고있으므로생활습관교정을통한체중감량이필수적이라는데는큰이견이없다. 거의대부분의선행연구에서도비알코올지방간질환환자에서체중감량은지방간의호전을유도하였다 [9,10]. 최근에는간내지방의양을평가하는방법으로 Magnetic resonance spectroscopy (MRS) 가매우우수하다고알려져있으며간조직생검결과와매우높은일치도를보인다. MRS 를이용한연구에서운동과식이요법으로체중의 5-10% 를감량하였을때간내지방량은유의하게감소하여체중감량과 간내지방의감소가밀접한관련이있다는것이확인되었다 [11]. 또한간내지방량감소뿐아니라 7-10% 이상의체중감량은조직학적으로염증의호전을유도하였다 [12,13]. 일부연구에서는 MRS를이용하여측정한결과체중이약 2.6% 감소할경우간내중성지방은약 20% 감소하였다 [14]. 체중감량과관련되어많이제기되는다른문제는적절한체중감량의속도이다. 체중감량의적절한속도에대하여는적절한연구결과가부족한현실이다. 선행연구에서 1년간의영양상담으로조직학적호전을보인 9명의평균체중감량은 2.9 kg이었다 [15]. 국내연구에서 5년간평균 2.2 kg의체중감량이간내지방축적의감소와동반된대사이상을호전시켰다 [16]. 또다른연구에서도 1주일에최대 1 kg의점진적체중감소는간내염증을유의하게감소시켰으나 [15] 체중감량의변동이큰경우에는문맥염증및섬유화를악화시켰다는보고가있고 [17], 일부무리한체중감량은간손상을악화시키고간부전으로진행되었다는보고가있어급격한체중감량은주의해야한다 [18]. 대한간학회진료지침에서는체중감량은치료시작당시의체중의 5-7% 감량을목표로한다 [4]. 체중감량과관련되어제기되는또다른화두는 체중감량이간내의염증과섬유화를회복시킬수있는가 이다. 최근 Thoma 등 [19] 은비알코올지방간환자에서생활습관개선의치료효과에대한체계적고찰 (systematic review) 을시행하였다. 이연구에는식이요법및운동요법을통한생활습관개선이간내지방량과혈청간효소수치를감소시키는결과를보였다. 하지만조직학적인개선은일부연구에서만있는것으로나타났다. 생활습관의개선을통한체중감소는비알코올지방간질환의가장중요한치료방법이라는것에대하여는다른의견이없을것이다. 그러나생활습관개선을통한체중감소는장기적인순응도가매우낮기때문에의사, 영양사, 운동트레이너, 심리학자를포함한종합적인팀의협조하에행동치료를통해생활습관을개선하는것이필요하다고하겠다. 항비만약물및비만수술을통한체중감소가지방간질환에미치는영향체중감량을위하여널리사용하던약제는 orlistat, sibutramine, rimonabant 등이있었으나 sibutramine은심혈관계질환의부작용, rimonabant는심한정신질환발생의부작용때문

3 - 대한내과학회지 : 제 86 권제 4 호통권제 644 호 에각각시장에서퇴출된상태이고 phetermine은단기간만사용가능한약제이다. 현재장기간의처방은 orlistat만가능하다. orlistat는위, 췌장의 lipase 억제제로서장내지방의흡수를감소시켜서체중을감량시킨다. 10명의비만한조직학적으로확진된지방간염환자에서 orlistat 120 mg을하루 3회 6개월간투여했을때체중을감소시키고간효소수치를개선시켰다 [12]. 비알코올지방간환자에서 orlistat를투여한무작위대조군연구는두개가있는데 Zelber-Sagi 등 [20] 은위약군에비해유의하게간효소수치개선및영상학적간내지방량감소 (48% vs. 26%) 를가져왔다고보고하였으나 Harrison 등 [21] 의보고에따르면위약군에비해추가적인체중감소나조직학적인호전을보이지않았다. 결론적으로비알코올지방간질환의치료를목적으로항비만약물사용을사용하는것은권장되지않는다. 식이및운동요법, 약물치료에반응하지않는건강을위협할정도의심한일부비만환자를대상으로비만수술이최근시행되고있다. 선행연구에서비만수술은통계적으로유의한체중감소와비알코올지방간질환의개선을보고하였으며건강을위협할정도의심한비만환자에서비만수술을시행하였을때장기간의체중감소와사망률의감소를보였다 [22,23]. 미국의경우체질량지수가 40 이상이거나 35 이상이면서당뇨병, 심장병, 수면무호흡증등을동반한경우비만수술을고려할수있다고제시하였다 [24]. 비만수술은위의용적을줄여음식물의섭취를제한하는제한수술 (restrictive procedure) 과음식물이소장의일부를우회하도록하여영양분의흡수를억제하는흡수장애수술 (malabsorptive procedure) 로나눌수있다. 제한수술에는위밴드술 (gastric banding), 위소매절제술 (sleeve gastrectomy) 이있으며흡수장애수술에는담도췌장우회술 / 십이지장전환술 (biliopancreatic diversion/duodenal switch) 이있고두가지기전을동시에갖고있는혼합형인루와이위우회술 (Roux-en-Y gastric bypass) 이있다. 이중미국에서가장많이시행되고있는수술은혼합형의루와이위우회술 (Roux-en-Y gastric bypass) 이다. 비만수술이체중감량을통하여간내지방의양을감소시킨다는것은주지의사실로받아들여지고있다. 그러나비만수술이비알코올지방간질환에서역할과관련되어가장주목받는부분은비만수술이지방간염을동반한환자에서간내염증및섬유화를감소시킬수있는지여부이다. Mathurin 등 [25] 은비만수술을시행한지방간질환자에서 5년간추적관찰을시행한연구에서체질량지수, 간내지방량및간내염증정도, 인슐린저항성, 수축기혈압, 혈청지질의감소를확인하였지만추적관찰중섬유화지수는상승하였다고보고하였다. 비알코올지방간염환자에서비만수술의역할에대한두개의체계적고찰 (systematic review) 에서 Mummadi 등 [26] 은 15개연구, 766명의비알코올지방간, 지방간염환자에서비만수술을시행하였을때조직학적으로간내지방량은 91% 에서호전되었고간내염증은 81% 에서, 섬유화는 65% 에서감소하여매우효과적인것으로보고하였으나 Chavez-Tapia 등 [27] 은잘계획된무작위대조군연구가없어비만수술이비알코올지방간염에효과적이라는결론을내릴수없다고밝혔다. 비만수술과관련하여제기되는다른이슈는 수술로인한급격한체중감량이치명적인간기능부전을유발할수있는가 이다. 선행연구에서공장- 회장우회술을시행한아주일부의환자에서간부전에의한사망이보고된바가있다 [28]. 그러나공장- 회장우회술이외의다른수술을시행한경우에는이와같은보고는거의없는것으로알려지고있다. 미국간학회가이드라인에서는비만수술이비만을동반한비알코올지방간환자에게표준적인치료는아니지만간경변이없는환자에서비만수술이금기는아니라고밝히고있다 [2]. 식이패턴이지방간발생에미치는영향식생활습관에있어서비알코올지방간발생에가장중요한요인은총칼로리섭취량이다. 흥미로운점은한달이내의단기간의총칼로리섭취량의증가로도인슐린저항성및지방간이발생될수있다는점이다 [29,30]. 건강한성인에게 4주간칼로리섭취량을증가시켰을때, 간내중성지방량은 2배증가하였으며혈청 ALT는 3배증가하였다 [29,30]. 최근총칼로리섭취량과더불어효과적대량영양소 ( 지방, 탄수화물, 단백질 ) 의구성비율이비만및비알코올지방간발생에중요한역할을하는것으로알려져관심이높다 [31]. 전통적으로지방을많이섭취하는것이비만, 대사질환및지방간을유도한다는것은주지의사실이다. 일본의연구진이매우흥미로운연구결과를발표하였는데, 간내지방축적의대부분을차지하는중성지방을선택적으로억제하였을때간내지방의축적은감소하였지만오히려간내염증과섬유화는증가하였다는연구결과를보고하였다 [32]. 최근에

4 - 유기덕외 1 인. 비알코올지방간질환 : 생활습관치료 - 는총지방의양보다지방의종류가보다중요하다고제시되고있으며이러한개념을 lipid compartment theory 또는 lipid partitioning theory 로불려진다. 비알코올지방간환자에서섭취하는지방의종류에대한연구에서비알코올지방간환자들이포화지방산을더많이섭취하고그중에서도 n-3 불포화지방산 (polyunsaturated fatty acid) 을적게섭취하는경향을보였다 [33]. 동시에올리브유의풍부한단일불포화지방산 (monounsaturated fatty acid) 과생선기름에많이포함되어있는 n-3 다가불포화지방산 (polyunsaturated fatty acid, PUFA) 은지방간및심혈관질환의발생률을낮춘다 [34]. 이렇게최근연구의경향은 지방의양 보다는 지방의종류 에대하여보다많은관심이이루어지고있다. 임상에서가장널리알려진불포화지방산은오메가-3이다. 오메가-3 지방산이고중성지방혈증및대사질환에좋은영향이있다는문헌보고가있지만비알코올지방간질환에서오메가-3의적절한용량은아직정해지지않았으며아직잘시행된무작위대조군연구결과가적어추가연구가들이필요한실정이다 [35,36]. 다량영양소중에 지방섭취량 과 종류 이외에탄수화물의섭취가비만, 인슐린저항성발생에또다른주요원인으로인식되고있다 [37]. 탄수화물은체내에서인슐린분비를자극하는강력한인자이며증가된인슐린은말초지방을분해하여결국간내로들어오는유리지방산을증가시켜지방간을유발한다. 또한동시에인슐린은간내지방의신생합성 (de novo synthesis) 을증가시키는효과를가진다. 흥미로운점은탄수화물의과잉섭취는간내지방의양을증가시켜지방간을유발하는것이외에간내염증의정도와밀접한관련이있다는것이다. 비알코올지방간환자에서탄수화물의섭취비중이높은환자에서간조직학적염증소견이더욱심했다는보고가있으며 [38,39] 일본에서시행한연구에서도비알코올지방간염환자의식습관비교연구에서지방간염환자군에서단순지방간환자보다탄수화물의섭취가의미있게많았다 [40]. 우리나라국민건강영양조사결과를분석한연구에서도지방의에너지섭취비율보다탄수화물의에너지섭취비율이혈청 AST, ALT 상승에미치는영향이더욱컸다고보고하였다 [41]. 이러한현상은탄수화물의에너지섭취비율이우리나라의경우 65.6% 로미국의 51.7% 에비해절대적으로높고, 상대적으로지질의에너지섭취비율은우리나라의경우 20.5% 로미국의 32.9% 에비하여낮은것에기인할것으로 사료된다. 저탄수화물식이와저지방식이가비만조절에미치는영향에대한메타분석에서저탄수화물식이가저지방식이보다비만및대사증후군조절에더좋은효과를보였다는보고가있었다. 저탄수화물식이요법과저지방식이요법을비교한무작위대조군연구에서는양군모두에서간내지방량이감소되었다 [42]. 기호식품섭취와비알코올지방간질환종실류및견과류종실류및견과류의섭취는비알코올지방간질환발생에예방효과가있다고알려져있다. 이는종실류및견과류에많이함유되어있는불포화지방산과같은성분에의한항산화효과와지질개선효과가지방간발생을예방한다고생각한다 [43]. 트랜스지방트랜스지방 (trans-fatty acid) 의섭취는심혈관질환및인슐린저항성의발생과매우밀접한관계가있다고알려져있다. 트랜스지방산은한개이상의이중결합을갖고있는불포화지방산으로, 자연에서얻어진식품에서는드물고주로음식을가공하면서발생되는지방의형태이다. 마가린, 쇼트닝등이대표적인예로주로튀김, 케이크, 아이스크림, 햄등을만들때사용된다. 동물실험에서트랜스지방의섭취는내당능장애를보였고콜레스테롤, 중성지방의농도를증가시키고간내지방합성증가에따라서지방간염과유사한병변이생겼으며 C-reactive protein (CRP) 을증가시켰다 [44]. 저지방식이에서트랜스지방을섭취를늘리면고지방식이와유사하게간내지방량이증가하였다 [45]. 과당 (fructose) 최근가공식품섭취가폭발적으로증가하면서트랜스지방과함께과당 ( 단순당 ) 섭취가가파르게증가하고있다. 미국의연구자료에따르면기원전의과당섭취량은연간 2 kg 으로추정되었으나 1950년대에는 45 kg, 1997년에는 69 kg으로과당섭취량이기하급수적으로증가하였다 [46]. 우리나라의경우도최근 3년간당류섭취량이 23% 증가하는것으로나타났다 [47]. 과당은탄산음료, 주스, 과자등의인스턴트식품에단맛을내는데사용되고있다. 31명의정상체중을가진비알코올지방간환자와건강한대조군비교연구에서

5 - The Korean Journal of Medicine: Vol. 86, No. 4, 비알코올지방간환자군에서월등히많은탄산음료를섭취하고있었다 (81% vs. 17%) [48]. 과당은섭취가과다하였을때포만감을유도하여식욕을억제하는기전이없어간세포내에과다한지방의합성을촉진하는결과를초래하며 [49] 지속적인과당의투여는세포의에너지 (adenosine triphosphate) 를급속하게감소시켜세포사멸을유도한다 [46]. 또한장기간의과당투여는장내세균총의분포변화를유도하여소장내세균의과증식, 장투과도증가등을일으켜간내염증을유발할수있다고알려져있다 [50]. 채소및과일류섭취식이섬유는위배출시간을지연시켜포만감을유지시켜체중감량에효과가있다. 또한소화를지연시켜인슐린의급격한분비를억제하는효과가있으며장내세균총개선에기여한다고알려져있다. 수용성식이섬유가섭취한지방을흡착하여체외로일부를배출시켜지방간질환및대사증후군을예방했다는보고도있다. Musso 등 [51] 은 25명의조직검사로확진된비알코올지방간환자군에서대조군과비교하였을때식이섬유의섭취가적었다고보고하였으나, Zelber- Sagi 등 [52] 은단면연구에서 108명의비만한초음파로진단된비알코올지방간환자에서식이섬유의섭취는대조군과비교시에큰차이가없었다고보고하였다. 따라서비알코올지방간에식이섬유의역할에대해서는더연구가필요할것으로생각된다. 커피및차커피의섭취가간질환진행을억제하고간암의발생을낮출수있다는많은역학결과가보고되고있다. 커피가비알코올지방간발생을억제한다는연구결과도많이있는데비알코올지방간환자를대상으로커피섭취량을조사한결과커피의섭취량과간내섬유화의정도는역의상관관계를보였다 [53]. 일반적으로카페인의섭취는지방간발생을낮추는것으로나타났다 [54]. 하지만중요한것은적절한커피섭취량인데일본의경우하루에 5잔이상의커피를마시는경우대사증후군과간염증수치가의미있게낮았다 [55]. 우리나라연구결과에서는하루에커피를 2잔이상섭취하는경우고혈압의유병률, 공복혈당이상및고지혈증의빈도가낮았으며, 대사증후군의발생빈도가의미있게낮았다 [56]. 우리나라식품의약품안전처에서권고하는하루카페인섭취량은 400 mg으로일반적으로커피전문점에서판매되는한 잔의커피에약 mg의카페인이있다고가정할때하루에약 3잔이내가적절할것으로생각된다. 커피가일부간보호기능을가지는것은커피의주된성분인카페인과연관이있을것으로생각되지만카페인을제거한커피에서도지방간억제효과가있다는연구결과도있어커피의지방간억제효과가카페인에의한것인지커피내에있는항산화효과를가지는물질에의한것인지분명하지않다 [57]. 항산화효과, 저지질, 항염효과를가지는폴리페놀이풍부한녹차도비알코올지방간진행및발병예방효과가있다는연구결과가있다 [58]. 홍차 (black tea) 는대사및항염효과를가진폴리페놀이풍부한음료이다. 한연구에의하면, 고과당식이를하고있는동물에서홍차추출물을추가하였을때, 고혈당, 이상지질혈증, 간내지방축적, 염증, 세포사멸이방지되었다는보고가있다 [59]. 녹차는동물실험에서일일식이섭취에영향없이체중감소, 간내지방량감소, 지질의과산화에효과가있었다 [60,61]. 차를좋아하는일본인을대상으로한연구에서녹차를즐겨마시는사람은그렇지않은사람과비교하여심혈관계질환과간염증수치가의미있게낮았다. 특히하루에 10잔이상의녹차를마시는경우지질성분개선및혈청 AST, ALT의감소가더뚜렷하였다 [62]. 하지만녹차는매우낮은경구 bioavailability를가지고있기때문에대부분의연구에서매일 5-10잔이상의섭취를하는군에서효과가있었으며일부과량의녹차추출물을복용후에간독성발생보고도있다 [58]. 현재까지는비알코올지방간환자에게차를마시는것은충분한근거가없는상태이다. 비알코올지방간질환에서운동요법 (physical activity) 운동및활동량이비만및비알코올지방간발생에중요한원인요인이라는것은주지의사실이다. 선행연구에서도앉아있는시간이많은사람, 즉신체활동이부족하거나운동을하지않는사람에서비알코올지방간의유병률이높았다 [63]. 운동은식이조절과더불어서체중감량에중요한역할을한다. 비알코올지방간질환과관련하여운동치료와관련되어제기되는핵심질문은 체중감량이없어도운동요법은효과적인가? 와 어느정도의어떤종류의운동이지방간질환호전에효과적인가? 이다. 결론적으로운동은체중감량이외에도비알코올지방간질환에도움을줄수있다 [64-66]. 선행연구에서운동은체중

6 - Ki Deok Yoo, et al. NAFLD: Lifestyle modification - 감량이나신체조성의변화없이도인슐린감수성과포도당항상성을증가시키고전신의지질산화를증가시켜서유리지방산의대사에도이득이있다. 결국운동은체중감소를동반하지않더라도지방간을호전시킬수있다 [14,67-70]. 그러나운동이간내지방량감소이외에간내염증및섬유화를호전시킬수있는지에대한연구는매우적다. 일부연구에서운동은체중감소와관련없이대사지표및간염증수치를감소시켰다는보고들이있었으나 [71,72] 최근의체계적고찰 (systematic review) 에따르면운동은간내지방량은감소시켰으나간염증수치감소와의관련성은추가적인연구가필요할것으로생각된다 [73]. 운동요법과관련하여두번째제기되는핵심질문은운동의종류, 강도및시간에대한것이다. 기존의연구들에서운동요법은주로일상활동에유산소운동을추가하는것이었다. 운동요법의종류및적절한강도와운동시간에대한합의는아직없다. 대표적인유산소운동의종류로는걷기, 조깅, 수영, 자전거타기등을들수있는데연구마다차이가있지만, 운동의강도는중등도 ( 최대심박수의 50-70%) 를추천하였고운동시간은일주일에 2-3회, 한번에 30-60분, 6-12 주의규칙적인운동이었다 [64-66]. 운동의종류는유산소운동이광범위하고더욱효과적일것으로판단되나덤벨등의기구를이용해서근육운동을하는저항력훈련 (resistance training) 도비알코올성지방간에효과가있는것으로알려져있다 [74]. 저항력훈련으로인한체내근육의증가는기초대사율을높이고인슐린저항성을개선시켜저항력훈련이체중의감소없이인슐린저항성, 공복혈당을낮추고내장지방을감소시키는것으로알려져있다 [74,75]. 또한최근저항력훈련이유산소운동과동등한효과가있었다는보고도있다 [76]. 저항력훈련은신체적인제한이있거나유산소운동을시행하는데동기부여가적어서유산소운동을시행하기어려운경우에는저항력훈련이추천된다. 운동만으로체중을줄이는것은쉽지않으며특히유지하는것은더욱어렵다. 일반적으로운동만으로체중을감소하기위해서는일주일에 150분이상의중등도운동또는 75분이상의고강도운동이필요하다. 2년간의추적에따르면순응도가평균적으로 20% 정도밖에되지않는다는보고가있다 [77]. 운동치료프로그램을최대한유지할수있도록생활습관개선의행동및인지치료에더욱초점을두고개개인에적합한장기간지속이가능하고흥미있는운동을선택하여 식이조절과병행하여꾸준히할수있도록의사, 영양사, 운동트레이너, 심리학자를포함한종합적인팀의도움을받는것이중요하다. 결 비만, 좌식생활, 건강하지않은식단의증가에따라비알코올지방간질환의발생이전세계적으로증가하고있다. 비알코올지방간질환은지방이간세포내에침착된이후에세포내염증과괴사에의해간염과간경변증으로진행될수있다. 또한비알코올지방간질환을가지고있는환자는향후당뇨, 대사증후군, 심혈관계질환의발생위험이높은것으로알려지고있어현재비알코올지방간질환은대상질환및심혈관계질환발생의독립적인위험인자로여겨지고있다. 많은약물이개발되어임상시험을진행하고있으나비알코올지방간질환의치료의근간은생활습관개선이라고하겠다. 그러나생활습관개선은순응도가매우낮기때문에치료를유지하기위해서는의사, 영양사, 운동트레이너, 심리학자등의다수의팀접근이필요하다고하겠다. 그러나아쉽게도아직우리나라에서는비알코올지방간질환에대한영양교육, 운동교육, 및심리교육에대한수가가정하여지지않아임상에서다각적이고입체적인팀접근이어려운현실이다. 향후비알코올지방간환자에대하여영양사, 운동처방에대한비용- 효과에대한연구가필요하겠다. 중심단어 : 비알코올지방간질환 ; 생활습관개선 ; 치료 론 REFERENCES 1. Musso G, Cassader M, Gambino R. Diagnostic accuracy of adipose insulin resistance index and visceral adiposity index for progressive liver histology and cardiovascular risk in nonalcoholic fatty liver disease. Hepatology 2012;56: Chalasani N, Younossi Z, Lavine JE, et al. The diagnosis and management of non-alcoholic fatty liver disease: practice Guideline by the American Association for the Study of Liver Diseases, American College of Gastroenterology, and the American Gastroenterological Association. Hepatology 2012;55: Loria P, Adinolfi LE, Bellentani S, et al. Practice guidelines for the diagnosis and management of nonalcoholic fatty liver disease: a decalogue from the Italian Association for

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