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1 JMBS J Metab Bariatr Surg 2017;6(1): REVIEW ARTICLE 고도비만환자의수술전후위 - 식도역류질환 단국대학교병원외과 김동욱, 지예섭 Gastroesophageal Relfux Disease in Morbid Obesity Patients Dong-Wook Kim, Ye Seob Jee Department of Surgery, Dankook University Hospital, Cheonan, Korea There has been a sharp increase in the number of obese people worldwide thanks to modern prosperity in accordance with rapid industrialization and economic development. Recently, bariatric surgery has been applied actively to extremely obese patients (BMI>35 kg/m 2 ) and presented as an alternative solution to provide not only weight loss but also a treatment for metabolic diseases such as diabetes mellitus, hypertension, and hyperlipidemia. Gastroesophageal reflux disease (GERD) is one of the most important diseases in morbidly obese patients, and many patients suffer from symptoms like epigastric pain, regurgitation, and dry cough. However, such symptoms are easy to be overlooked and studies on GERD are scarce in relation to bariatric surgery. In morbidly obese patients, high abdominal pressure leads to a pressure gradient between esophagus and stomach. This induces a hiatal hernia causing a greater likelihood of GERD. Many studies in regards to GERD were made after bariatric surgery (sleeve gastrectomy, Roux-en-Y gastric bypass, and gastric band), and various results have been presented. Studies should be carried out on pre-operative diagnosis of GERD, choice of operative method, and improvement of symptoms after the operation. Research is also needed upon bariatric operation in patients with uncontrolled GERD. Key Words: Morbid obesity, GERD, Bariatric surgery 서론 빠른산업화와경제발전으로인한풍요로운삶은전세계적으로비만인구의급격한증가를가져왔다. 미국을포함한서양의경우에서는전체인구의약 35% 정도가비만으로진단된다 [1]. 최근의통계는없으나 2005년의자료에따르면국내에서도서양과비슷하여 20세이상의성인에서 31.5% 의유병률을보이고있다 [2]. 비만환자는당뇨, 고혈압, 고지혈증등여러대사성 동반질환을가지고있으며최근에는체질량지수 (body mass index, BMI) 35 이상의고도비만환자에있어서는다양한수술적치료를통해체중감소와동시에대사성동반질환의개선및치료의가능성을보여주고있다. 그리고비만환자에서대사성합병증외에동반되는중요한질환중하나는위-식도역류질환 (gastroesophageal reflux disease, GERD) 이다. 일반적으로체질량지수가증가할수록위-식도역류질환의유병률이증가하고증상또한심해져서비만환자의삶의질을심각하게저하시 투고일 : 2017 년 5 월 10 일, 심사일 : 2017 년 5 월 22 일, 게재확정일 : 2017 년 5 월 22 일책임저자 : 지예섭, 천안시동남구단대로 119 단국대학교병원외과우 : Tel: , Fax: , ysjee@dkuh.co.kr CC This is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Copyright 2017, The Korean Society for Metabolic and Bariatric Surgery

2 Vol. 6, No. 1, 2017 킨다 [3,4]. 그러나, 고도비만수술시위-식도역류질환은대사성질환과달리간과되기쉽고이에대한연구도부족한실정이다. 또한, 비만환자의위-식도역류질환은수술후체중감소와함께호전되나일부에서는수술후호전되지않고오히려하부식도괄약근의손상및남은위의과도한압력으로수술후역류증상이새로이발생하거나악화를보이는경우도있다. 그러므로수술전비만환자의위-식도역류질환에대한진단과수술후발생하는위-식도역류에대한고찰이필요할것으로보인다. 본론 1. 고도비만환자의위-식도역류질환위-식도역류질환은위내용물이식도로역류해서발생하는일련의증상을의미한다. 이질환은환자의삶의질저하를초래하며의료비상승의원인으로지목되고있다 [5]. 위내용물의역류로부터식도손상을방지하는기전은위-식도접합부의항역류방어 (antireflux barrier), 식도의정화기능 (clearance mechanism), 그리고상피세포의방어기능이다 [6]. 일반인의위식도역류질환의유병률은서양에서 10-20% 정도, 동양에서는 5% 이하로보고되고있으나 [3] 비만환자에있어서는최대 61% 까지증가한다. 이처럼유병률이증가하는이유는비만환자에서복압의증가로인한항역류방어기전의손상으로설명할수있다. 항역류방어기전으로는하부식도괄약근, crural diaphragm, 식도-횡경막인대에의해흡기시등과같이복압이증가하는상황에서하부식도를높은압력으로유지하는역할을하며, 히스각은식도와위의각또는꺾임을만들게하여역류를방지하게된다. 비만환자에서는일반인보다복압이상승하여식도와위의압력차이가상대적으로높게발생하며또한 crural diaphragm과하부식도괄약근의분리, 즉열공헤르니아 (hiatal hernia) 로인해일반인보다위-식도역류질환발생이높아지게된다 [6]. Jacobson 등 [7] 은체질량지수와역류증상의정도는비례하며높은체질량지수가위-식도역류질환의가장중요한원인이라고지목하였다. 그이유로는비만환자신체의구조적인이유, 즉복압의증가가가장중요한원인이며이와함께호르몬특히지방세포 (adipocyte) 에서분비되는호르몬을원인으로제시되었다. 또다른연구에서는체질량지수 25 이상의위 -식도역류질환환자에서체중감소는증상의개선에가장큰도움이된다고하였으며 [7-9] 이는비만이위-식도역류질환의가장중요한원인이라는것을시사한다. 국내에서도위식도역류질환이빠르게증가하고있으며이러한원인중의하나는비만환자의증가로기인한것으로보인다. 2. 비만수술과위-식도역류질환 1) 위소매절제술위소매절제술은루와이위우회술 (Roux-en-Y gastric bypass) 전체중감소를위한중간단계의수술방법이었으나상대적으로낮은합병증및단독수술만으로체중감소의효과가입증되어최근에는대표적인섭취제한수술로많이시행되고있는수술법중하나이다 [10]. 위소매절제술과위-식도역류질환에관한연구는다른수술방법에비해많이시행된편이지만연구의결과가모두일치하지는않는다. 즉, 위소매절제술후기존의위-식도역류질환의증상이개선되었다는몇몇연구가있는반면에대다수의연구에서는위-식도역류질환이수술후새로이발생하였거나기존의증상이악화되었다고주장하고있다 [11-16]. 이러한상이한연구결과의차이는두가지로설명할수있다. 첫째, 위-식도역류질환을측정하는도구및시기가서로상이하기때문이다. 대부분의연구에서주간적인지표로 PPI의감량또는증량정도, 증상설문지, 내시경을통한식도염의유무를사용하였으며객관적인지표인 24시간식도 ph 측정도구를사용한연구는드물었다. 또한위식도역류를진단한연구시점또한수술후 6개월, 1년또는 2년등으로다양했다. 이는수술이후기간에따라체중감소정도의차이가발생하므로시점이상이한연구들을비교하는것은다소무리가있다. 둘째로는수술방법의차이때문일가능성이있다. 남은위의모양이위-식도역류질환의발생에중요한역할을한다는가정하에위의중간부분절제를많이하고윗부분, 즉위의바닥부분 (gastric fundus) 의절제를적게할경우위바닥부분의음식물이배출되는시간이지연되고위의상부에음식물및위산의저류가생겨결국에는식도로역류되어위-식도역류질환의발생률을증가시킬수있다. 실제로 Toro 등 [17] 등은수술직후상부위장관조영술을시행하여위소매의모양을 upper pouch, lower pouch, dumbbell 그리고 tubular 네가지형태로분류한뒤환자에게역류질환에대한증상을설문조사하였다. Upper pouch 환자에서다른모양에비해심각한역류증상이의미있게높게조사되었으며 (P=0.02) 이러한결과는수술의방법즉남은소매의모양이역류질환과관련되어있다는것을시사하므로위-식도역류질환의연구결과에영향을미칠수있다. 또다른수술적관점은수술전에위-식도역류질환을가진환자에서수술중식도열공을복원하는것이다. 수술전위-식도역류질환을가진환자에서위소매절제술의적응증에대해서는논란의여지가있으며또한, 이러한환자에서수술중열공을복원하는것에대해서도논란의여지가있다. 많은연구에서수술중식도열공을복원하는것이 GERD 의증상개선이도움이된다고하였으나 [18,19] 최근의연구에서는 [20,21] 식도열공을복원하지않은그룹에서복원한그룹 20

3 김동욱, 지예섭 : 고도비만과위 - 식도역류질환 보다 GERD의개선을보여연구의결과가일치하지는않는다. 그러므로수술중식도열공을복원할지에대해서와어떤방법으로복구 (posterior cruroplasty, anterior cruroplasty, hiatal hernia repair with mesh) 할지에대한대규모의전향적연구가필요할것으로생각된다. 마지막으로경험많은비만수술외과의사는위-소매절제술시식도역류를방지할수있는몇가지방법을제안하였다. 그방법으로는위소매가꺾이거나각이지는것 (angulation) 을피해위소매가곧게펴지게해야하고위의바닥부분절제를적절하게하여수술후일정기간이지난후위의저부가확장되어 neofundus가발생하는것을방지해야하며, 40Fr. 이하의작은부지의사용을금지하는것이다. 또한주장하는사람에따라식도열공을반드시복구해야한다고하였다 [22-25]. 2) 루와이위우회술루와이우회술은고도비만수술의표준일뿐만아니라위식도역류질환을가진환자에게서도표준치료로시행되고있다. 루와이위우회술이역류를방지하는기전은첫째루림 (Roux-limb) 으로부터담즙이우회되며, 체중감소로인해상대적으로복압이감소되는것이다 [26]. 또한, 위주머니 (gastric pouch) 내에위산의농도가낮으며음식물의위배출시간이빨라위-하부식도괄약근의압력을낮추기때문이다. 대부분의연구에서주관적인증상의개선뿐만아니라 24시간식도 ph 측정을통해객관적인질환의개선을보여주었다 [27-31]. 또한다른수술방법즉위소매절제술및위밴드삽입술에비해서도위-식도역류질환의개선에우월한결과를보였다 [32]. 그러므로루와이위우회술은위-식도역류질환을가진고도비만환자에있어서표준수술로받아들여지고있다. 또한이전에위소매절제술또는위밴드삽입술을시행받았던환자에게서위-식도역류질환이조절되지않을경우루와이위우회술을고려할수있다. Varela 등 [33] 에의하면루와이위우회술은복강경위바닥주름술 (laparoscopic Nissen fundoplication) 과비교하여수술의안전성에차이가없으며위-식도역류질환증상개선효과가더욱우수하여 (P <0.05) 위-식도역류질환을가진고도비만환자에서위바닥주름술보다루와이위우회술을권장한다고보고하였다. 또한최근연구결과에의하면복강경위바닥주름술을시행받았던환자에서위-식도역류질환치료에실패하였을경우위바닥주름술을교정하는것보다루와이위우회술을시행하는것이더욱효과가있었다는보고도있다 [34]. 3) 조절형위밴드삽입술조절형위밴드삽입술은수술이간단하고안정성이우수하여고도비만환자의수술에많이사용되어왔으나최근후기합병증에대한보고이후점차줄어들고있는추세이다. 조절형위밴드삽입술은위주머니 (gastric pouch) 를만들면서히스각의변 화, 식도-횡격막인대의손상및위배출시간의지연으로인한높은위의압력, 그리고수술후식도운동장애및기능적인식도위접합부의폐색으로인한식도의배출지연으로이론적으로는위-식도역류질환을조장하는것으로알려져있다 [35-37]. 하지만조절형위밴드삽입술또한수술과위-식도역류질환에관한연구의결과는일치하지않는다. 조절형위밴드삽입술후위- 식도역류질환증상및식도 ph의개선을보였다는연구가있는반면에다른연구에서는위-식도역류질환의발생이증가했다는연구도있다. 위-식도역류질환의발생이증가했다는연구에서는밴드삽입후식도에서음식물의배출에지장이생겨식도운동에장애가생기며그결과하부식도의확장으로위식도역류질환이발생한다고주장하였다 [32,38,39]. 증상이감소하였다고주장하는연구에서는밴드를올바른위치에삽입하였을경우위에서언급한식도의변화는관찰되지않으며체중감소와함께위-식도역류질환또한증가하지않았다고보고하였다 [40]. 하지만이러한결과는단기적인결과이며장기간후에밴드의위치가이동할경우그리고체중이다시증가할경우위식도역류질환이발생할수있을것으로생각된다. 이러한연구결과의이유로수술전에위식도역류질환을가진환자에서는조절형위밴드삽입술은일반적으로권장되지않는다. 3. 수술후발생한위-식도역류질환의진단과치료 1) 진단위-식도역류질환의전형적인임상적증상은명치또는가슴을칼로찌르는듯한통증, 위내용물의역류, 기침등의증상이다 [6]. 하지만수술후발생한위-식도역류질환은수술전진단되지않았던식도의운동장애뿐만아니라수술후합병증과종종혼돈된다. 예를들어조절형위밴드삽입술후에발생한위-식도역류질환은부적절할밴드의위치, 너무꽉조여진밴드또는미끄러짐, 그리고위의밴드로부터의탈출 (prolapse) 에의해발생하기도한다. 루와이위우회술후에는위공장문합부위의협착 (stenosis) 에의해서발생하기도한다. 또한위소매절제술후에도위소매의모양에따라서위-식도역류질환이발생할수있기때문에진단에신중을기해야한다 [26]. 진단은우선일반인들에게서시행하는약물적치료와함께시작된다. 만약효과가있다면위-식도역류성질환으로진단을할수있고 (empiric PPI trial) 약물치료를지속하고 [5] 효과가없다면적극적인진단방법을사용하여진단해야한다. 진단방법으로는 24시간 ph 모니터, 바륨식도조영술, 위내시경검사와식도내압측정법등이있다. 이중 24시간 ph 모니터는 GERD의진단에가장중요하다. 바륨식도조영술은식도열공탈장및위장관의음식배출구의막힘을판단하는데도움이되며식도내압측정법은식도의운동장애를배제할수있다. 그리고위내시경 21

4 Vol. 6, No. 1, 2017 검사는바렛식도의존재유무, 식도염, 식도열공탈장을파악하는데도움이된다 [26]. 2) 치료우선적인치료는앞서언급한바와같이일반인과마찬가지로약물적치료이다. Proton pump inhibitor (PPI) 는위-식도역류질환의일차적인약물치료방법이며위장관운동조절제 (promotility agent) 를함께사용할수도있다. 생활습관의개선도치료에도움이될수있으며일차적으로는체중감소가중요하다. 그리고수면전 2-3시간이내에음식물섭취를피해야하며역류를일으킬수있는음식예를들어초콜릿, 카페인, 알코올, 산도가높은음식이나매운음식의섭취를줄여야한다 [5]. 하지만약물치료나생활습관개선에의해조절되지않고증상이지속되거나악화될경우, 그리고앞서언급한검사로수술적합병증등특별한원인이밝혀지지않을경우수술적치료를고려해야한다 [26]. 적절한체중감소에실패하고조절되지않는위식도역류질환의경우수술적치료의적응증이된다 [26]. 만약수술이조절형위밴드삽입술이나위소매절제술일경우루와이위우회술로의전환을고려해야한다. Langer 등 [41] 은위-소매절제술을시행한 73명의환자중심한위식도역류증상이발생한 3명의환자에대해서루와이전환술을시행하였다. 심한위식도역류의증상은고용량 ( 하루 80 mg) 의 PPI를사용해도증상의개선이없는환자였으며수술후모든환자에서증상의개선과함께 PPI 사용을중단할수있었다고발표하였다. 루와이위우회술후새롭게발생한위식도역류질환의치료는다양하다. 가장고전적인방법으로는루림의길이를연장하고위주머니의용량을줄이는술식이나, 최근에는우회된위를이용한위바닥주름술, 그리고 Linx device, MUSE system, Stretta Procedure, EsophyX 등새로운방법이시도되고있다 [26]. 결론 비만환자는당뇨, 고혈압, 고지혈증등의동반된대사질환과더불어위-식도역류질환의높은유병률을보이고있다. 동반된대사질환은체중감소로인한질환의개선또는치료가가능하며이에대한연구또한활발히진행되고있다. 비만환자에서발생한위-식도역류질환은이론적으로체중의감소와더불어복강내압력의감소로증상의소실및개선이가능하나수술방법에따라오히려악화또는새로이발병할수있다. 그러므로비만환자의수술전위-식도역류질환의진단그리고위-식도역류질환의유무에따른수술방법의선택, 수술후위-식도역류질환의증상을개선하거나발생을방지하는수술기법등의연구가진행되어야하며마지막으로기존에수술을시행받은환자에서조절되지않는위-식도역류질환의내과적및수술적치료법에 대한연구도필요할것으로보인다. REFERENCES 1. Ogden CL, Carroll MD, Kit BK, Flegal KM. Prevalence of obesity in the United States, NCHS Data Brief 2012;(82): Kang JH, Kim KS, Kim KJ, et al. The guideline of treatment for obese patient Korean Society for the Study of the Obesity, Dent J, El-Serag HB, Wallander MA, Johansson S. Epidemiology of gastro-oesophageal reflux disease: a systematic review. Gut 2005;54: Peery AF, Dellon ES, Lund J, et al. Burden of gastrointestinal disease in the United States: 2012 update. Gastroenterology 2012; 143: e Katz PO, Gerson LB, Vela MF. Guidelines for the diagnosis and management of gastroesophageal reflux disease. Am J Gastroenterol 2013;108: Cecil RL, Goldman L, Ausiello DA. Cecil medicine. 24th ed. Amsterdam: Elsevier, Jacobson BC, Somers SC, Fuchs CS, Kelly CP, Camargo CA Jr. Body-mass index and symptoms of gastroesophageal reflux in women. N Engl J Med 2006;354: Fraser-Moodie CA, Norton B, Gornall C, Magnago S, Weale AR, Holmes GK. Weight loss has an independent beneficial effect on symptoms of gastro-oesophageal reflux in patients who are overweight. Scand J Gastroenterol 1999;34: Mathus-Vliegen LM, Tytgat GN. Twenty-four-hour ph measurements in morbid obesity: effects of massive overweight, weight loss and gastric distension. Eur J Gastroenterol Hepatol 1996; 8: Hutter MM, Schirmer BD, Jones DB, et al. First report from the American College of Surgeons Bariatric Surgery Center Network: laparoscopic sleeve gastrectomy has morbidity and effectiveness positioned between the band and the bypass. Ann Surg 2011; 254: Tai CM, Huang CK, Lee YC, Chang CY, Lee CT, Lin JT. Increase in gastroesophageal reflux disease symptoms and erosive esophagitis 1 year after laparoscopic sleeve gastrectomy among obese adults. Surg Endosc 2013;27: Himpens J, Dapri G, Cadière GB. A prospective randomized study between laparoscopic gastric banding and laparoscopic isolated sleeve gastrectomy: results after 1 and 3 years. Obes Surg 2006; 16: Braghetto I, Csendes A, Korn O, Valladares H, Gonzalez P, Henríquez A. Gastroesophageal reflux disease after sleeve gastrectomy. Surg Laparosc Endosc Percutan Tech 2010;20: Carter PR, LeBlanc KA, Hausmann MG, Kleinpeter KP, debarros SN, Jones SM. Association between gastroesophageal reflux disease and laparoscopic sleeve gastrectomy. Surg Obes Relat Dis 2011;7: Himpens J, Dobbeleir J, Peeters G. Long-term results of laparoscopic sleeve gastrectomy for obesity. Ann Surg 2010;252: Menenakos E, Stamou KM, Albanopoulos K, Papailiou J, Theodorou D, Leandros E. Laparoscopic sleeve gastrectomy performed with intent to treat morbid obesity: a prospective single-center 22

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A 617 Special Issue Diabetic Retinopathy Won Ki Lee, M.D. Department of Ophthalmology The Catholic University of Korea College of Medicine Kangnam St. Mary s Hospital E mail : wklee@catholic.ac.kr Abstract R