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    Gut and Liver is an international journal of gastroenterology, focusing on the gastrointestinal tract, liver, biliary tree, pancreas, motility, and neurogastroenterology. Gut atnd Liver delivers up-to-date, authoritative papers on both clinical and research-based topics in gastroenterology. The Journal publishes original articles, case reports, brief communications, letters to the editor and invited review articles in the field of gastroenterology. The Journal is operated by internationally renowned editorial boards and designed to provide a global opportunity to promote academic developments in the field of gastroenterology and hepatology. +MORE

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Real-World National Colonoscopy Volume in Korea: A Nationwide Population-Based Study over 12 Years

Jae Myung Cha1 , Min Seob Kwak1 , Hyun-Soo Kim2 , Su Young Kim2 , Sohee Park3 , Geun U Park4 , Jung Kuk Lee5 , Soo Jin Kim6 , Hun Hee Lee6 , Joo Sung Kim7 , Won Ho Kim8

1Department of Internal Medicine, Kyung Hee University School of Medicine, Seoul, 2Department of Internal Medicine, Yonsei University Wonju College of Medicine, Wonju, 3Department of Biostatistics, Graduate School of Public Health, Yonsei University, 4Department of Biostatics and Computing, Yonsei University, Seoul, 5Department of Biostatistics, Yonsei University Wonju College of Medicine, Wonju, 6Department of Biostatistics, Kyung Hee University Hospital at Gangdong, 7Department of Internal Medicine, Seoul National University School of Medicine, and 8Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea

Correspondence to: Hyun-Soo Kim
Department of Internal Medicine, Yonsei University Wonju College of Medicine, 20 Ilsan-ro, Wonju 26426, Korea
Tel: +82-33-741-0505, Fax: +82-33-747-3538, E-mail: hyskim@yonsei.ac.kr

Received: March 22, 2019; Revised: May 25, 2019; Accepted: June 7, 2019

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Gut Liver 2020;14(3):338-346. https://doi.org/10.5009/gnl19108

Published online September 19, 2019, Published date May 15, 2020

Copyright © Gut and Liver.

Background/Aims: Little is known about the national colonoscopy volume in Asian countries. This study aimed to assess the national colonoscopy volume in Korea over a 12-year period on the basis of a nationwide population-based database. Methods: We conducted a population-based study for colonoscopy claims (14,511,158 colonoscopies performed on 13,219,781 patients) on the basis of the Korean National Health Insurance Service database from 2002 to 2013. The 12-year national colonoscopy burden was analyzed according to patient age, patient sex, and healthcare facility type. Results: The overall volume of colonoscopy increased 8-fold over the 12-year period. The annual colonoscopic polypectomy rate significantly increased in all patient sex and age groups over the 12-years period (all p<0.001). The yearly colonoscopic polypectomy rate for men was significantly increased compared with that for women (2.3% vs 1.7%, p<0.001) and for the screening-age group compared with that for the young-age group (2.0% vs 1.6%, p<0.001). The yearly colonoscopic polypectomy rate relative to the total colonoscopy volume significantly increased in primary, secondary, and tertiary facilities by 2.4%, 1.9%, and 1.4% during the 12-year period (all p<0.001). In addition, the annual colonoscopy volume covered by high-volume facilities significantly increased by 1.8% in primary healthcare facilities over the 12-year period (p<0.001). Conclusions: Healthcare resources should be prioritized to allow adequate colonoscopic capacity, especially for men, individuals in the screening-age group, and at primary healthcare facilities. Cost-effective strategies to improve the quality of colonoscopy may focus on primary healthcare facilities and high-volume facilities in Korea.

Keywords: Big data, Colonoscopy, Polypectomy, Population

Colorectal cancer (CRC) is a significant public health problem, as its incidence has been increasing worldwide.1,2 Colonoscopy is very effective to reduce the risk of CRC, as most CRCs develop from colorectal adenoma through the adenoma-carcinoma sequence.3-5 CRC screening rate has been steadily increasing over the years, which significantly prevents the development of CRC.6 As a national CRC screening program, most countries, including Korea, use fecal occult blood tests, whereas several Western countries use colonoscopy.6,7 The national CRC screening program in Korea coexists alongside opportunistic colonoscopy screening of persons with an average risk of CRC.8

In Western countries, limited resources for colonoscopy have been an obstacle in expanding CRC screening program, because only certain specialists are trained to perform colonoscopy and colonoscopic polypectomy.9-12 The estimated colonoscopy capacity was sufficient to screen 80% of the eligible U.S. population with fecal test, colonoscopy, or a mix of tests in 2014.9 Survey study conducted in the United Kingdom reported that 50% of the endoscopy units provided an adequate colonoscopy service.12 In some Asian countries such as Korea, Japan, and China, however, colonoscopy burden may be different from that of Western countries because of the excellent accessibility of colonoscopy, low cost of colonoscopy, and many available experienced colonoscopists.13 Currently, however, no population-based studies have reported the national burden of colonoscopy in Asian countries. A better understanding of national colonoscopy burden may be the first step toward successful implementation of CRC screening program as well as identification of deficits in the current colonoscopy resources in Asian countries.

In this context, we aimed to assess the national burden of colonoscopy according to age, sex, and healthcare facility type, based on a nationwide population-based database in Korea.

1. Data source and study population

This study is a retrospective nationwide population-based study using the Korean National Health Insurance Service (NHIS) database, which contains all inpatient and outpatient data nationwide since 1989 in Korea. The NHIS database provides a comprehensive healthcare coverage for all Koreans and contains information on claims billed by physicians for services, admissions, diagnoses, procedures, discharge status, and patient demographics.14,15 Procedure codes in physician claims databases had a very high level of agreement with data in medical charts.15

We identified all persons who had at least one colonoscopy in the NHIS physician billing claims database between January 2002, and December 2013. Longitudinal time change in the national burden of colonoscopy was assessed according to age, sex, and healthcare facility type in 12 years. We determined whether patients had undergone colonoscopy without polypectomy (E7660) or with polypectomy (Q7701, single polypectomy; Q7702, two or more polypectomies; Q7703, endoscopic mucosal resection) using NHIS codes. In this study, colonoscopic polypectomy included endoscopic mucosal resection (Q7703), but endoscopic submucosal dissection was excluded because this procedure is rarely performed and not reimbursed by NHIS. Colonoscopic procedures were analyzed per procedure, as some patients had multiple colonoscopic procedures, whereas an early repeat colonoscopy within 12 months was analyzed per patient.

Study variables were time (2002 to 2013), colonoscopy with or without polypectomy, age groups (young age, <50 years; screening age, 50 to 74 years; and elderly age, ≥75 years), sex, healthcare facility type (primary, secondary, tertiary, and others) and annual volume of facility (high-volume or not). Age group classification was based on the current guidelines that recommend CRC screening for 50- to 75-year-old adults at an average risk for CRC.4,5 Primary facility includes a primary outpatient clinic, secondary facility includes a hospital and a general hospital, and tertiary facility includes a specialized general hospital on referral from primary and secondary healthcare facility. Other facility includes dental hospital, nursing hospital, public hospital, and oriental hospital/clinic (traditional medicine hospital/clinics prescribing herbal drug or practicing acupuncture). A high-volume facility was defined as a facility with an annual colonoscopy volume more than 200 cases, because the minimum volume of annual colonoscopy to maintain competency for colonoscopy was 200 cases per year and other universal definition is not available.16,17 As a unique situation in Korea, primary healthcare facility includes profit health promotion centers which account for most of high-volume center. As the information used in this study was related only to pseudonyms, the requirement of informed consent was waived. This study was approved by the Institutional Review Board of Kyung Hee University Hospital at Gangdong, Seoul, Republic of Korea (IRB number: KHNMC 2018-08-021).

2. Statistical analysis

Descriptive analysis was performed on the entire population during the study period. A generalized linear regression model was applied for sex, age group, and healthcare facility type using the annual proportion of colonoscopy/polypectomy among the total volume of colonoscopy at each year, compared with those in 2002 as a reference. The trends in the annual colonoscopic polypectomy burden in each age group were assessed by subtraction using the chi-square distribution. All statistical tests were two-sided, and a p-value <0.05 was considered statistically significant. All statistical analyses were conducted using SAS 9.4 statistical software (SAS institute Inc., Cary, NC, USA) and R software packages R version 3.5.1 (R Foundation for Statistical Computing, Vienna, Austria; https://www.R-project.org).

1. National burden of colonoscopy

Table 1 shows the longitudinal time change in the national colonoscopy burden for 12 years, based on 14,511,158 colonoscopies on 13,219,781 patients. Compared with the total volume of colonoscopy in 2002, the total volume of colonoscopy doubled within 2 years in 2004, quadrupled within 5 years in 2007, hextupled within 8 years in 2010, and octupled within 10 years in 2012. The annual proportion of polypectomy performed at each year among the total volume of colonoscopy significantly increased by +2.0% from 2002 to 2013 (p<0.001). However, in-patient polypectomy rate per year significantly decreased by –2.4% (p<0.001).

2. National burden of colonoscopy according to sex and age group

The overall colonoscopy burden was higher in men than women with ratio of 1.2 to 1 (Table 2). Compared with the volume of polypectomy in 2002, the proportion of polypectomy among the total volume of colonoscopy per year was significantly increased for both sexes in 12 years (both p<0.001). For sex difference, the proportion of polypectomy performed at each year among the total volume of colonoscopy was significantly increased in men than in women (2.3% vs 1.7%, p<0.001).

The burden of total colonoscopy in young age, screening age, and elderly age groups was 38.8%, 57.2%, and 4.0%, respectively (Table 3). Compared with the volume of polypectomy in 2002, the proportion of polypectomy among the total volume of colonoscopy per year was significantly increased for all age groups in 12 years (all p<0.001). For age group difference, the proportion of polypectomy among the total volume of colonoscopy per year significantly increased in the screening and elderly age groups compared with the young age group (2.0% and 2.1% vs 1.6%, both p<0.001).

3. National burden of colonoscopy according to healthcare facility type

Our analysis was focused on primary, secondary, and tertiary facilities, as the colonoscopy volume in other facility type was only 0.2% (Table 4). The number of facilities claimed that colonoscopy procedures increased by 3.2-fold and 4.8-fold in primary and secondary facilities in 12 years. In total, 41.3%, 43.3%, and 15.2% of polypectomies were performed in primary, secondary, and tertiary facilities for 12 years. Compared with the colonoscopy database in 2002, the proportion of polypectomy among the total volume of colonoscopy per year significantly increased in primary, secondary, and tertiary facilities by 2.4%, 1.9%, and 1.4%, respectively (all p<0.001). The annual polypectomy rate of each facility type among total polypectomies was significantly increased only in the primary facilities (p<0.001), but, significantly decreased in the tertiary facilities (p<0.001) and not changed in the secondary facilities (p=0.274) (Fig. 1).

4. Colonoscopy burden by high-volume facility

Compared to that in the 2002 database, the number of high-volume facility significantly increased by 2.8% and by 2.0% in primary and secondary facilities (both p<0.001), but was not changed in the tertiary facilities (p>0.1) (Table 5). The annual colonoscopy volume covered by a high-volume facility among the total volume of colonoscopy significantly increased in primary and secondary facilities by 1.8% and by 0.4% per year (both p<0.001), but it was not changed in the tertiary facilities in 12 years (p=0.196).

5. Early repeat colonoscopy within 12 months

Overall, 8.4% of 13,219,781 persons had an early repeat colonoscopy, and 3.3% of 10,922,565 persons had an early repeat colonoscopy without polypectomy by per-patient analysis (Supplementary Table 1). The proportion of an early repeat colonoscopy without polypectomy among the total volume of colonoscopy significantly decreased in 12 years (by 0.3% for two colonoscopies and by 0.1% for ≥3 colonoscopies) (both p<0.001).

This population-based study is the first Asian study that investigated the national colonoscopy volume according to age, sex, and healthcare facility type. The national colonoscopy volume has progressively increased in all sex, age groups, and healthcare facility types in the 12 years. The volume of colonoscopic polypectomy significantly increased in men than in women and in the screening age group than in the young age group. These findings are predictable because old age and male sex are well-known risk factors for colorectal neoplasia.18,19 The colonoscopic polypectomy volume significantly increased in the primary facility than the secondary and tertiary facility. A steep rise in the volume of colonoscopy by the primary healthcare facilities may be explained by the introduction of the “National CRC Screening Program” in 2004 in Korea.8 In Canada, similarly, the proportion of colonoscopies performed in the nonhospital setting increased with the introduction of the “ColonCancerCheck” program: 18.9% increase from 2000 to 200720 and 35.1% increase from 2013 to 2014.21 Higher rates of the polypectomy in the primary healthcare facilities may be explained by that diminutive polyps may be removed by polypectomy, not by biopsy forceps, as well as that non-adenomatous polyps on the distal colon may be removed by polypectomy in primary healthcare facilities. Our findings may indicate that healthcare resources should be prioritized such that there is adequate colonoscopic capacity, especially for men, screening age group, and primary healthcare facilities.

We could estimate the capacity of screening colonoscopy at the population level on the basis of our data. In 2012, 15,537,702 Koreans were invited to undergo CRC screening and 3,884,839 (25.0%) of them underwent CRC screening with the “National CRC Screening Program.”8 One-third of the colonoscopic capacity may be used for CRC screening, because screening indication was about one-third of the total colonoscopy.22 Theoretically, if the 3,884,839 persons are eligible for CRC screening and one-third (i.e., 699,617) of the total volume of colonoscopy of 2012 are provided, 5.6 years may be required to screen the potential population of CRC screening in 2012. Therefore, 5- to 10-year interval of screening colonoscopy may cover all eligible CRC screening population in Korea. However, the potential capacity of screening colonoscopy at the population level may consider the growing rate of the target population, participation rate of screening program, screening interval, cost-effectiveness, and safety and quality of colonoscopy screening.

In previous studies, the quality of colonoscopy was suboptimal in primary healthcare facilities.20,21,23-25 In a population-based study from Ontario,20 the odds ratio of early repeat colonoscopy ≤5 years after a negative complete colonoscopy was 1.26 when the index colonoscopy had been performed in a nonhospital setting. Similarly, the adjusted odds ratio for an early repeat colonoscopy ≤6 months was 1.41 when baseline colonoscopy was performed at a nonhospital facility compared with a teaching or community hospital.21 The early repeat colonoscopy at a nonhospital facility may be explained by their suboptimal baseline colonoscopy. In addition, direct access colonoscopy of primary facility had lower detection rate of large (≥10 mm) polyp and lower completion rate of colonoscopy than conventional colonoscopy group.23 An important variation in colonoscopy quality among outpatient facilities was suggested by significant variation in the unplanned hospital visits within 7 days of colonoscopy.24 In a retrospective study from Florida,25 a higher risk of adverse events was associated with colonoscopies performed in ambulatory surgery centers (odds ratio, 1.27; 95% confidence interval, 1.16 to 1.40). Considering the predominantly increasing colonoscopy volume in primary healthcare facilities, the colonoscopy quality improvement program may be reinforced in primary healthcare facilities.

We also investigated the volume of an early repeat colonoscopy within 12 months. The volume of an early repeat colonoscopy without polypectomy among the total volume of colonoscopy decreased by 0.3% for two colonoscopies and by 0.1% for ≥3 colonoscopies from 2002 to 2013. In Canada, 2.4% of 334,663 persons had an early repeat colonoscopy within 6 months.21 In the Veterans Health Administration data,26 colonoscopy was used more frequently than the recommended intervals on guidelines by 16% of patients without adenoma. In addition, 46.2% of the Medicare population underwent a repeated examination within 7 years and 23.5% of patients had no clear indication for the early repeat examination.27 In our study, the number of high-volume facility significantly increased in primary and secondary facilities, and the annual colonoscopy volume covered by the high-volume facilities also increased regardless of facility types. For example, only 11.7% of colonoscopy volume in primary facilities and 3.2% of colonoscopy volume in secondary facilities was performed in low-volume facilities in 2013. Therefore, the cost-effective strategy to increase colonoscopy quality may be focused on high-volume facilities in Korea.

The use of a NHIS enabled us to perform the largest study to date that assessed the national volume of colonoscopy, and the results are virtually free from referral bias and readily generalizable owing to the population-based design. However, some limitations should be considered. We concede that one of the limitations of our study is secondary data with the uncertainty regarding the accuracy of the diagnosis. However, previous studies with NHIS as data sources have generally shown that procedures and diagnoses are coded accurately.14,15 As no specific details of the colonoscopy were recorded in the NHIS, safety, quality, and the cost of colonoscopy were not addressed in this study. In addition, we cannot assess detailed clinical information for the cause of an early repeat colonoscopy within 12 months. We defined high-volume facility (i.e., annual colonoscopy volume ≥200) based on some evidence,16,17 but it may still be arbitrary as it was a criterion for an endoscopist, not a healthcare facility. In a German screening colonoscopy registry, the detection rate of any neoplasm was better for annual colonoscopy volume ≥200 than annual colonoscopy volume <50 (27.5% vs 21.9%, p<0.001).16 Spanish Society of Gastrointestinal Endoscopy also recommended at least 200 annual screening colonoscopies to maintain colonoscopy quality in CRC screening.17

In conclusion, the national volume of colonoscopy has been progressively increasing regardless of sex, age group, and healthcare facility types for the past 12 years in Korea. Healthcare resources should be prioritized such that there is adequate colonoscopic capacity, especially for men, subjects of screening age, and primary healthcare facilities. Considering difference in colonoscopy quality among facilities and majority of colonoscopy volume covered by high-volume facility, cost-effective strategy to improve colonoscopy quality may be focused on primary healthcare facilities and high-volume facilities in Korea.

This study was supported by grants from the Korean Society of Gastroenterology, the National R&D Program for Cancer Control (HA17C0046 and 1720230) and the Korean National Health Clinical Research (NHCR) project (HC16C2320), Ministry of Health and Welfare, Republic of Korea. Data source: National Health Information Database (NHIS-2018-4-062) made by the National Health Insurance Service (NHIS) was used.

No potential conflict of interest relevant to this article was reported.

Study concept and design, analysis, and interpretation of data, drafting of the manuscript, critical revision of the manuscript for important intellectual content: J.M.C., H.S.K. Data management, statistical analysis: M.S.K., G.U.P., S.P., J.K.L., S.Y.K., S.J.K., H.H.L. Acquisition of data, administrative, and technical support of this study: J.S.K., W.H.K. Study supervision: J.M.C., H.S.K., J.S.K., W.H.K.

Fig. 1.Annual colonoscopic polypectomy volume in each type of healthcare facility. The proportion of colonoscopic polypectomies performed relative to the total polypectomy volume significantly increased by 1.6% in primary facilities and decreased by 1.8% in tertiary facilities (both p<0.001) compared with the rates in the 2002 database.

National Colonoscopy Burden over the 12-Year Period in Korea

Year Total volume Colonoscopy without polypectomy* Colonoscopic polypectomy* In-patient polypectomy
2002 264,345 240,167 (90.8) 24,178 (9.1) 9,523 (39.4)
2003 448,051 408,397 (91.1) 39,654 (8.9) 16,016 (40.4)
2004 546,190 487,466 (89.2) 58,724 (10.8) 23,367 (39.8)
2005 751,535 657,790 (87.5) 93,745 (12.5) 35,033 (37.4)
2006 957,534 812,859 (84.9) 144,675 (15.1) 45,369 (31.4)
2007 1,080,359 892,151 (82.6) 188,208 (17.4) 54,583 (29.0)
2008 1,207,613 968,661 (80.2) 238,952 (19.8) 61,273 (25.6)
2009 1,441,564 1,136,222 (78.8) 305,342 (21.2) 75,095 (24.6)
2010 1,601,688 1,226,376 (76.6) 375,312 (23.4) 84,706 (22.6)
2011 1,975,279 1,467,324 (74.3) 507,955 (25.7) 96,464 (19.0)
2012 2,138,150 1,542,315 (72.1) 595,835 (27.9) 103,647 (17.4)
2013 2,098,850 1,474,064 (70.2) 624,786 (29.8) 105,374 (16.9)
Percent change –2.0 +2.0 –2.4

Data are presented as number or number (%).

*The percent is the proportion of procedures performed each year relative to the total colonoscopy volume.


National Colonoscopy Burden According to Sex over the 12-Year Period in Korea

Year Men Women


Total volume Colonoscopy without polypectomy* Polypectomy* Total volume Colonoscopy without polypectomy* Polypectomy*
2002 144,252 127,678 (88.5) 16,574 (11.5) 120,093 112,489 (93.7) 7,604 (6.3)
2003 241,827 214,526 (88.7) 27,301 (11.3) 206,224 193,871 (94.0) 12,353 (6.0)
2004 293,264 252,753 (86.2) 40,511 (13.8) 252,926 234,713 (92.8) 18,213 (7.2)
2005 408,158 344,383 (84.4) 63,775 (15.6) 343,377 313,407 (91.3) 29,970 (8.7)
2006 523,894 426,143 (81.3) 97,751 (18.7) 433,640 386,716 (89.2) 46,924 (10.8)
2007 600,398 472,939 (78.8) 127,459 (21.2) 479,961 419,212 (87.3) 60,749 (12.7)
2008 666,918 507,257 (76.1) 159,661 (23.9) 540,695 461,404 (85.3) 79,291 (14.7)
2009 792,350 590,410 (74.5) 201,940 (25.5) 649,214 545,812 (84.1) 103,402 (15.9)
2010 882,390 634,393 (71.9) 247,997 (28.1) 719,298 591,983 (82.3) 127,315 (17.7)
2011 1,115,603 776,992 (69.6) 338,611 (30.4) 859,676 690,332 (80.3) 169,344 (19.7)
2012 1,198,330 804,831 (67.2) 393,499 (32.8) 939,820 737,484 (78.5) 202,336 (21.5)
2013 1,166,880 761,413 (65.3) 405,467 (34.7) 931,970 712,651 (76.5) 219,319 (23.5)
Percent change –2.3 +2.3 –1.7 +1.7

Data are presented as number or number (%).

*The percent is the proportion of procedures performed each year relative to the total colonoscopy volume.


National Colonoscopy Burden According to Age Group over the 12-Year Period in Korea

Year Young age (<50 yr) Screening age (50–74 yr) Elderly age (≥75 yr)



Total volume CS without polypectomy Polypectomy Total volume CS without polypectomy* Polypectomy* Total volume CS without polypectomy* Polypectomy*
2002 131,431 124,226 (94.5) 7,205 (5.5) 125,060 109,097 (87.2) 15,963 (12.8) 7,854 6,844 (87.1) 1,010 (12.9)
2003 229,271 217,796 (95.0) 11,475 (5.0) 206,768 180,233 (87.2) 26,535 (12.8) 12,012 10,368 (86.3) 1,644 (13.7)
2004 267,815 251,194 (93.8) 16,621 (6.2) 262,325 222,634 (84.9) 39,691 (15.1) 16,050 13,638 (85.0) 2,412 (15.0)
2005 361,729 335,013 (92.6) 26,716 (7.4) 367,829 304,638 (82.8) 63,191 (17.2) 21,977 18,139 (82.5) 3,838 (17.5)
2006 442,551 401,190 (90.7) 41,361 (9.3) 483,284 386,253 (79.9) 97,031 (20.1) 31,699 25,416 (80.2) 6,283 (19.8)
2007 479,373 425,120 (88.7) 54,253 (11.3) 563,229 437,513 (77.7) 125,716 (22.3) 37,757 29,518 (78.2) 8,239 (21.8)
2008 508,168 439,933 (86.6) 68,235 (13.4) 654,693 494,628 (75.6) 160,065 (24.4) 44,752 34,100 (76.2) 10,652 (23.8)
2009 578,202 494,490 (85.5) 83,712 (14.5) 807,666 600,228 (74.3) 207,438 (25.7) 55,696 41,504 (74.5) 14,192 (25.5)
2010 588,331 493,360 (83.9) 94,971 (16.1) 946,442 684,963 (72.4) 261,479 (27.6) 66,915 48,053 (71.8) 18,862 (28.2)
2011 709,141 577,893 (81.5) 131,248 (18.5) 1,186,855 834,456 (70.3) 352,399 (29.7) 79,283 54,975 (69.3) 24,308 (30.7)
2012 691,351 552,549 (79.9) 138,802 (20.1) 1,351,311 926,350 (68.6) 424,961 (31.4) 95,488 63,416 (66.4) 32,072 (33.6)
2013 649,927 507,664 (78.1) 142,263 (21.9) 1,340,951 896,796 (66.9) 444,155 (33.1) 107,972 69,604 (64.5) 38,368 (35.5)
Percent change –1.6 +1.6 –2.0 +2.0 –2.1 +2.1

Data are presented as number or number (%).

*The percent is the proportion of procedures performed each year relative to the total colonoscopy (CS) volume.


National Colonoscopy Burden According to Healthcare Facility Type over the 12-Year Period in Korea

Year Primary healthcare facility Secondary healthcare facility


Total facility Total CS volume CS without polypectomy* Polypectomy Total facility Total CS volume CS without polypectomy* Polypectomy
2002 741 97,302 89,447 (91.9) 7,855 (8.1) 213 89,074 80,322 (90.2) 8,752 (9.8)
2003 941 173,580 161,535 (93.1) 12,045 (6.9) 307 172,338 155,935 (90.5) 16,403 (9.5)
2004 1,118 208,541 188,736 (90.5) 19,805 (9.5) 454 225,861 200,916 (89.0) 24,945 (11.0)
2005 1,281 286,832 252,915 (88.2) 33,917 (11.8) 571 328,030 286,629 (87.4) 41,401 (12.6)
2006 1,508 367,715 312,673 (85.0) 55,042 (15.0) 660 425,631 361,774 (85.0) 63,857 (15.0)
2007 1,635 420,900 346,348 (82.3) 74,552 (17.7) 717 481,575 397,277 (82.5) 84,298 (17.5)
2008 1,791 479,126 380,046 (79.3) 99,080 (20.7) 809 538,892 433,290 (80.4) 105,602 (19.6)
2009 1,894 584,781 452,727 (77.4) 132,054 (22.6) 856 627,587 499,776 (79.6) 127,811 (20.4)
2010 2,040 664,000 497,557 (74.9) 166,443 (25.1) 908 696,670 539,123 (77.4) 157,547 (22.6)
2011 2,221 862,130 627,247 (72.8) 234,883 (27.2) 950 857,009 642,009 (74.9) 215,000 (25.1)
2012 2,316 938,075 661,358 (70.5) 276,717 (29.5) 992 923,782 671,683 (72.7) 252,099 (27.3)
2013 2,408 918,035 626,622 (68.3) 291,413 (31.7) 1,020 916,029 648,732 (70.8) 267,297 (29.2)
Percent change –2.4 +2.4 –1.9 +1.9

Year Tertiary healthcare facility Other healthcare facility

Total facility Total CS volume CS without polypectomy* Polypectomy Total facility Total CS volume CS without polypectomy* Polypectomy

2002 41 77,969 70,398 (90.3) 7,571 (9.7) 0 0 0 (0.0) 0 (0.0)
2003 42 102,126 90,921 (89.0) 11,205 (11.0) 1 7 6 (85.7) 1 (14.3)
2004 43 111,648 97,691 (87.5) 13,957 (12.5) 5 140 123 (87.9) 17 (12.1)
2005 41 136,467 118,046 (86.5) 18,421 (13.5) 14 206 200 (97.1) 6 (2.9)
2006 43 163,608 137,889 (84.3) 25,719 (15.7) 18 580 523 (90.2) 57 (9.8)
2007 45 176,816 147,695 (83.5) 29,121 (16.5) 28 1,068 831 (77.8) 237 (22.2)
2008 48 188,401 154,408 (82.0) 33,993 (18.0) 53 1,194 917 (76.8) 277 (23.2)
2009 44 227,388 182,176 (80.1) 45,212 (19.9) 69 1,808 1,543 (85.3) 265 (14.7)
2010 44 238,498 187,558 (78.6) 50,940 (21.4) 84 2,520 2,138 (84.8) 382 (15.2)
2011 45 252,192 194,992 (77.3) 57,200 (22.7) 97 3,948 3,076 (77.9) 872 (22.1)
2012 47 269,869 204,870 (75.9) 64,999 (24.1) 127 6,424 4,404 (68.6) 2,020 (31.4)
2013 45 259,116 194,901 (75.2) 64,215 (24.8) 136 5,670 3,809 (67.2) 1,861 (32.8)
Percent change –1.4 +1.4

Data are presented as number or number (%).

*The percent is the proportion of procedures performed each year relative to the total colonoscopy (CS) volume.


Colonoscopy Burden of HVFs over the 12-Year Period in Korea

Year Primary facility Secondary facility Tertiary facility



Total facility HVF Total CS volume CS by HVF Total facility HVF Total CS volume CS by HVF Total facility HVF Total CS volume CS by HVF
2002 741 138 (18.6) 97,302 65,532 (67.3) 213 78 (36.6) 89,074 81,441 (91.4) 41 38 (92.7) 77,969 77,607 (99.5)
2003 941 241 (25.6) 173,580 128,733 (74.2) 307 146 (47.6) 172,338 162,967 (94.6) 42 42 (100.0) 102,126 102,126 (100.0)
2004 1,118 310 (27.7) 208,541 159,744 (76.6) 454 195 (43.0) 225,861 209,954 (93.0) 43 42 (97.7) 111,648 111,646 (100.0)
2005 1,281 405 (31.6) 286,832 230,342 (80.3) 571 273 (47.8) 328,030 309,221 (94.3) 41 41 (100.0) 136,467 136,467 (100.0)
2006 1,508 497 (33.0) 367,715 302,222 (82.2) 660 363 (55.0) 425,631 407,472 (95.7) 43 42 (97.7) 163,608 163,599 (100.0)
2007 1,635 555 (33.9) 420,900 349,481 (83.0) 717 371 (51.7) 481,575 457,269 (95.0) 45 42 (93.3) 176,816 176,812 (100.0)
2008 1,791 623 (34.8) 479,126 400,216 (83.5) 809 418 (51.7) 538,892 511,956 (95.0) 48 43 (89.6) 188,401 188,372 (100.0)
2009 1,894 737 (38.9) 584,781 505,555 (86.5) 856 489 (57.1) 627,587 602,607 (96.0) 44 43 (97.7) 227,388 227,319 (100.0)
2010 2,040 824 (40.4) 664,000 578,234 (87.1) 908 518 (57.0) 696,670 668,812 (96.0) 44 43 (97.7) 238,498 238,482 (100.0)
2011 2,221 1,030 (46.4) 862,130 771,774 (89.5) 950 588 (61.9) 857,009 830,944 (97.0) 45 43 (95.6) 252,192 252,177 (100.0)
2012 2,316 1,113 (48.1) 938,075 847,351 (90.3) 992 613 (61.8) 923,782 896,816 (97.1) 47 46 (97.9) 269,869 269,704 (99.9)
2013 2,408 1,113 (46.2) 918,035 820,108 (89.3) 1,020 613 (60.1) 916,029 887,043 (96.8) 45 44 (97.8) 259,116 259,115 (100.0)
Percent change +2.8 +1.7 +2.0 +0.3 +0.0 +0.0

Data are presented as number or number (%). A high volume facility (HVF) was defined as a facility with an annual colonoscopy (CS) volume of more than 200 colonoscopies.


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Article

Original Article

Gut and Liver 2020; 14(3): 338-346

Published online May 15, 2020 https://doi.org/10.5009/gnl19108

Copyright © Gut and Liver.

Real-World National Colonoscopy Volume in Korea: A Nationwide Population-Based Study over 12 Years

Jae Myung Cha1 , Min Seob Kwak1 , Hyun-Soo Kim2 , Su Young Kim2 , Sohee Park3 , Geun U Park4 , Jung Kuk Lee5 , Soo Jin Kim6 , Hun Hee Lee6 , Joo Sung Kim7 , Won Ho Kim8

1Department of Internal Medicine, Kyung Hee University School of Medicine, Seoul, 2Department of Internal Medicine, Yonsei University Wonju College of Medicine, Wonju, 3Department of Biostatistics, Graduate School of Public Health, Yonsei University, 4Department of Biostatics and Computing, Yonsei University, Seoul, 5Department of Biostatistics, Yonsei University Wonju College of Medicine, Wonju, 6Department of Biostatistics, Kyung Hee University Hospital at Gangdong, 7Department of Internal Medicine, Seoul National University School of Medicine, and 8Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea

Correspondence to:Hyun-Soo Kim
Department of Internal Medicine, Yonsei University Wonju College of Medicine, 20 Ilsan-ro, Wonju 26426, Korea
Tel: +82-33-741-0505, Fax: +82-33-747-3538, E-mail: hyskim@yonsei.ac.kr

Received: March 22, 2019; Revised: May 25, 2019; Accepted: June 7, 2019

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Background/Aims: Little is known about the national colonoscopy volume in Asian countries. This study aimed to assess the national colonoscopy volume in Korea over a 12-year period on the basis of a nationwide population-based database. Methods: We conducted a population-based study for colonoscopy claims (14,511,158 colonoscopies performed on 13,219,781 patients) on the basis of the Korean National Health Insurance Service database from 2002 to 2013. The 12-year national colonoscopy burden was analyzed according to patient age, patient sex, and healthcare facility type. Results: The overall volume of colonoscopy increased 8-fold over the 12-year period. The annual colonoscopic polypectomy rate significantly increased in all patient sex and age groups over the 12-years period (all p<0.001). The yearly colonoscopic polypectomy rate for men was significantly increased compared with that for women (2.3% vs 1.7%, p<0.001) and for the screening-age group compared with that for the young-age group (2.0% vs 1.6%, p<0.001). The yearly colonoscopic polypectomy rate relative to the total colonoscopy volume significantly increased in primary, secondary, and tertiary facilities by 2.4%, 1.9%, and 1.4% during the 12-year period (all p<0.001). In addition, the annual colonoscopy volume covered by high-volume facilities significantly increased by 1.8% in primary healthcare facilities over the 12-year period (p<0.001). Conclusions: Healthcare resources should be prioritized to allow adequate colonoscopic capacity, especially for men, individuals in the screening-age group, and at primary healthcare facilities. Cost-effective strategies to improve the quality of colonoscopy may focus on primary healthcare facilities and high-volume facilities in Korea.

Keywords: Big data, Colonoscopy, Polypectomy, Population

INTRODUCTION

Colorectal cancer (CRC) is a significant public health problem, as its incidence has been increasing worldwide.1,2 Colonoscopy is very effective to reduce the risk of CRC, as most CRCs develop from colorectal adenoma through the adenoma-carcinoma sequence.3-5 CRC screening rate has been steadily increasing over the years, which significantly prevents the development of CRC.6 As a national CRC screening program, most countries, including Korea, use fecal occult blood tests, whereas several Western countries use colonoscopy.6,7 The national CRC screening program in Korea coexists alongside opportunistic colonoscopy screening of persons with an average risk of CRC.8

In Western countries, limited resources for colonoscopy have been an obstacle in expanding CRC screening program, because only certain specialists are trained to perform colonoscopy and colonoscopic polypectomy.9-12 The estimated colonoscopy capacity was sufficient to screen 80% of the eligible U.S. population with fecal test, colonoscopy, or a mix of tests in 2014.9 Survey study conducted in the United Kingdom reported that 50% of the endoscopy units provided an adequate colonoscopy service.12 In some Asian countries such as Korea, Japan, and China, however, colonoscopy burden may be different from that of Western countries because of the excellent accessibility of colonoscopy, low cost of colonoscopy, and many available experienced colonoscopists.13 Currently, however, no population-based studies have reported the national burden of colonoscopy in Asian countries. A better understanding of national colonoscopy burden may be the first step toward successful implementation of CRC screening program as well as identification of deficits in the current colonoscopy resources in Asian countries.

In this context, we aimed to assess the national burden of colonoscopy according to age, sex, and healthcare facility type, based on a nationwide population-based database in Korea.

MATERIALS AND METHODS

1. Data source and study population

This study is a retrospective nationwide population-based study using the Korean National Health Insurance Service (NHIS) database, which contains all inpatient and outpatient data nationwide since 1989 in Korea. The NHIS database provides a comprehensive healthcare coverage for all Koreans and contains information on claims billed by physicians for services, admissions, diagnoses, procedures, discharge status, and patient demographics.14,15 Procedure codes in physician claims databases had a very high level of agreement with data in medical charts.15

We identified all persons who had at least one colonoscopy in the NHIS physician billing claims database between January 2002, and December 2013. Longitudinal time change in the national burden of colonoscopy was assessed according to age, sex, and healthcare facility type in 12 years. We determined whether patients had undergone colonoscopy without polypectomy (E7660) or with polypectomy (Q7701, single polypectomy; Q7702, two or more polypectomies; Q7703, endoscopic mucosal resection) using NHIS codes. In this study, colonoscopic polypectomy included endoscopic mucosal resection (Q7703), but endoscopic submucosal dissection was excluded because this procedure is rarely performed and not reimbursed by NHIS. Colonoscopic procedures were analyzed per procedure, as some patients had multiple colonoscopic procedures, whereas an early repeat colonoscopy within 12 months was analyzed per patient.

Study variables were time (2002 to 2013), colonoscopy with or without polypectomy, age groups (young age, <50 years; screening age, 50 to 74 years; and elderly age, ≥75 years), sex, healthcare facility type (primary, secondary, tertiary, and others) and annual volume of facility (high-volume or not). Age group classification was based on the current guidelines that recommend CRC screening for 50- to 75-year-old adults at an average risk for CRC.4,5 Primary facility includes a primary outpatient clinic, secondary facility includes a hospital and a general hospital, and tertiary facility includes a specialized general hospital on referral from primary and secondary healthcare facility. Other facility includes dental hospital, nursing hospital, public hospital, and oriental hospital/clinic (traditional medicine hospital/clinics prescribing herbal drug or practicing acupuncture). A high-volume facility was defined as a facility with an annual colonoscopy volume more than 200 cases, because the minimum volume of annual colonoscopy to maintain competency for colonoscopy was 200 cases per year and other universal definition is not available.16,17 As a unique situation in Korea, primary healthcare facility includes profit health promotion centers which account for most of high-volume center. As the information used in this study was related only to pseudonyms, the requirement of informed consent was waived. This study was approved by the Institutional Review Board of Kyung Hee University Hospital at Gangdong, Seoul, Republic of Korea (IRB number: KHNMC 2018-08-021).

2. Statistical analysis

Descriptive analysis was performed on the entire population during the study period. A generalized linear regression model was applied for sex, age group, and healthcare facility type using the annual proportion of colonoscopy/polypectomy among the total volume of colonoscopy at each year, compared with those in 2002 as a reference. The trends in the annual colonoscopic polypectomy burden in each age group were assessed by subtraction using the chi-square distribution. All statistical tests were two-sided, and a p-value <0.05 was considered statistically significant. All statistical analyses were conducted using SAS 9.4 statistical software (SAS institute Inc., Cary, NC, USA) and R software packages R version 3.5.1 (R Foundation for Statistical Computing, Vienna, Austria; https://www.R-project.org).

RESULTS

1. National burden of colonoscopy

Table 1 shows the longitudinal time change in the national colonoscopy burden for 12 years, based on 14,511,158 colonoscopies on 13,219,781 patients. Compared with the total volume of colonoscopy in 2002, the total volume of colonoscopy doubled within 2 years in 2004, quadrupled within 5 years in 2007, hextupled within 8 years in 2010, and octupled within 10 years in 2012. The annual proportion of polypectomy performed at each year among the total volume of colonoscopy significantly increased by +2.0% from 2002 to 2013 (p<0.001). However, in-patient polypectomy rate per year significantly decreased by –2.4% (p<0.001).

2. National burden of colonoscopy according to sex and age group

The overall colonoscopy burden was higher in men than women with ratio of 1.2 to 1 (Table 2). Compared with the volume of polypectomy in 2002, the proportion of polypectomy among the total volume of colonoscopy per year was significantly increased for both sexes in 12 years (both p<0.001). For sex difference, the proportion of polypectomy performed at each year among the total volume of colonoscopy was significantly increased in men than in women (2.3% vs 1.7%, p<0.001).

The burden of total colonoscopy in young age, screening age, and elderly age groups was 38.8%, 57.2%, and 4.0%, respectively (Table 3). Compared with the volume of polypectomy in 2002, the proportion of polypectomy among the total volume of colonoscopy per year was significantly increased for all age groups in 12 years (all p<0.001). For age group difference, the proportion of polypectomy among the total volume of colonoscopy per year significantly increased in the screening and elderly age groups compared with the young age group (2.0% and 2.1% vs 1.6%, both p<0.001).

3. National burden of colonoscopy according to healthcare facility type

Our analysis was focused on primary, secondary, and tertiary facilities, as the colonoscopy volume in other facility type was only 0.2% (Table 4). The number of facilities claimed that colonoscopy procedures increased by 3.2-fold and 4.8-fold in primary and secondary facilities in 12 years. In total, 41.3%, 43.3%, and 15.2% of polypectomies were performed in primary, secondary, and tertiary facilities for 12 years. Compared with the colonoscopy database in 2002, the proportion of polypectomy among the total volume of colonoscopy per year significantly increased in primary, secondary, and tertiary facilities by 2.4%, 1.9%, and 1.4%, respectively (all p<0.001). The annual polypectomy rate of each facility type among total polypectomies was significantly increased only in the primary facilities (p<0.001), but, significantly decreased in the tertiary facilities (p<0.001) and not changed in the secondary facilities (p=0.274) (Fig. 1).

4. Colonoscopy burden by high-volume facility

Compared to that in the 2002 database, the number of high-volume facility significantly increased by 2.8% and by 2.0% in primary and secondary facilities (both p<0.001), but was not changed in the tertiary facilities (p>0.1) (Table 5). The annual colonoscopy volume covered by a high-volume facility among the total volume of colonoscopy significantly increased in primary and secondary facilities by 1.8% and by 0.4% per year (both p<0.001), but it was not changed in the tertiary facilities in 12 years (p=0.196).

5. Early repeat colonoscopy within 12 months

Overall, 8.4% of 13,219,781 persons had an early repeat colonoscopy, and 3.3% of 10,922,565 persons had an early repeat colonoscopy without polypectomy by per-patient analysis (Supplementary Table 1). The proportion of an early repeat colonoscopy without polypectomy among the total volume of colonoscopy significantly decreased in 12 years (by 0.3% for two colonoscopies and by 0.1% for ≥3 colonoscopies) (both p<0.001).

DISCUSSION

This population-based study is the first Asian study that investigated the national colonoscopy volume according to age, sex, and healthcare facility type. The national colonoscopy volume has progressively increased in all sex, age groups, and healthcare facility types in the 12 years. The volume of colonoscopic polypectomy significantly increased in men than in women and in the screening age group than in the young age group. These findings are predictable because old age and male sex are well-known risk factors for colorectal neoplasia.18,19 The colonoscopic polypectomy volume significantly increased in the primary facility than the secondary and tertiary facility. A steep rise in the volume of colonoscopy by the primary healthcare facilities may be explained by the introduction of the “National CRC Screening Program” in 2004 in Korea.8 In Canada, similarly, the proportion of colonoscopies performed in the nonhospital setting increased with the introduction of the “ColonCancerCheck” program: 18.9% increase from 2000 to 200720 and 35.1% increase from 2013 to 2014.21 Higher rates of the polypectomy in the primary healthcare facilities may be explained by that diminutive polyps may be removed by polypectomy, not by biopsy forceps, as well as that non-adenomatous polyps on the distal colon may be removed by polypectomy in primary healthcare facilities. Our findings may indicate that healthcare resources should be prioritized such that there is adequate colonoscopic capacity, especially for men, screening age group, and primary healthcare facilities.

We could estimate the capacity of screening colonoscopy at the population level on the basis of our data. In 2012, 15,537,702 Koreans were invited to undergo CRC screening and 3,884,839 (25.0%) of them underwent CRC screening with the “National CRC Screening Program.”8 One-third of the colonoscopic capacity may be used for CRC screening, because screening indication was about one-third of the total colonoscopy.22 Theoretically, if the 3,884,839 persons are eligible for CRC screening and one-third (i.e., 699,617) of the total volume of colonoscopy of 2012 are provided, 5.6 years may be required to screen the potential population of CRC screening in 2012. Therefore, 5- to 10-year interval of screening colonoscopy may cover all eligible CRC screening population in Korea. However, the potential capacity of screening colonoscopy at the population level may consider the growing rate of the target population, participation rate of screening program, screening interval, cost-effectiveness, and safety and quality of colonoscopy screening.

In previous studies, the quality of colonoscopy was suboptimal in primary healthcare facilities.20,21,23-25 In a population-based study from Ontario,20 the odds ratio of early repeat colonoscopy ≤5 years after a negative complete colonoscopy was 1.26 when the index colonoscopy had been performed in a nonhospital setting. Similarly, the adjusted odds ratio for an early repeat colonoscopy ≤6 months was 1.41 when baseline colonoscopy was performed at a nonhospital facility compared with a teaching or community hospital.21 The early repeat colonoscopy at a nonhospital facility may be explained by their suboptimal baseline colonoscopy. In addition, direct access colonoscopy of primary facility had lower detection rate of large (≥10 mm) polyp and lower completion rate of colonoscopy than conventional colonoscopy group.23 An important variation in colonoscopy quality among outpatient facilities was suggested by significant variation in the unplanned hospital visits within 7 days of colonoscopy.24 In a retrospective study from Florida,25 a higher risk of adverse events was associated with colonoscopies performed in ambulatory surgery centers (odds ratio, 1.27; 95% confidence interval, 1.16 to 1.40). Considering the predominantly increasing colonoscopy volume in primary healthcare facilities, the colonoscopy quality improvement program may be reinforced in primary healthcare facilities.

We also investigated the volume of an early repeat colonoscopy within 12 months. The volume of an early repeat colonoscopy without polypectomy among the total volume of colonoscopy decreased by 0.3% for two colonoscopies and by 0.1% for ≥3 colonoscopies from 2002 to 2013. In Canada, 2.4% of 334,663 persons had an early repeat colonoscopy within 6 months.21 In the Veterans Health Administration data,26 colonoscopy was used more frequently than the recommended intervals on guidelines by 16% of patients without adenoma. In addition, 46.2% of the Medicare population underwent a repeated examination within 7 years and 23.5% of patients had no clear indication for the early repeat examination.27 In our study, the number of high-volume facility significantly increased in primary and secondary facilities, and the annual colonoscopy volume covered by the high-volume facilities also increased regardless of facility types. For example, only 11.7% of colonoscopy volume in primary facilities and 3.2% of colonoscopy volume in secondary facilities was performed in low-volume facilities in 2013. Therefore, the cost-effective strategy to increase colonoscopy quality may be focused on high-volume facilities in Korea.

The use of a NHIS enabled us to perform the largest study to date that assessed the national volume of colonoscopy, and the results are virtually free from referral bias and readily generalizable owing to the population-based design. However, some limitations should be considered. We concede that one of the limitations of our study is secondary data with the uncertainty regarding the accuracy of the diagnosis. However, previous studies with NHIS as data sources have generally shown that procedures and diagnoses are coded accurately.14,15 As no specific details of the colonoscopy were recorded in the NHIS, safety, quality, and the cost of colonoscopy were not addressed in this study. In addition, we cannot assess detailed clinical information for the cause of an early repeat colonoscopy within 12 months. We defined high-volume facility (i.e., annual colonoscopy volume ≥200) based on some evidence,16,17 but it may still be arbitrary as it was a criterion for an endoscopist, not a healthcare facility. In a German screening colonoscopy registry, the detection rate of any neoplasm was better for annual colonoscopy volume ≥200 than annual colonoscopy volume <50 (27.5% vs 21.9%, p<0.001).16 Spanish Society of Gastrointestinal Endoscopy also recommended at least 200 annual screening colonoscopies to maintain colonoscopy quality in CRC screening.17

In conclusion, the national volume of colonoscopy has been progressively increasing regardless of sex, age group, and healthcare facility types for the past 12 years in Korea. Healthcare resources should be prioritized such that there is adequate colonoscopic capacity, especially for men, subjects of screening age, and primary healthcare facilities. Considering difference in colonoscopy quality among facilities and majority of colonoscopy volume covered by high-volume facility, cost-effective strategy to improve colonoscopy quality may be focused on primary healthcare facilities and high-volume facilities in Korea.

ACKNOWLEDGEMENTS

This study was supported by grants from the Korean Society of Gastroenterology, the National R&D Program for Cancer Control (HA17C0046 and 1720230) and the Korean National Health Clinical Research (NHCR) project (HC16C2320), Ministry of Health and Welfare, Republic of Korea. Data source: National Health Information Database (NHIS-2018-4-062) made by the National Health Insurance Service (NHIS) was used.

CONFLICTS OF INTEREST

No potential conflict of interest relevant to this article was reported.

AUTHOR CONTRIBUTIONS

Study concept and design, analysis, and interpretation of data, drafting of the manuscript, critical revision of the manuscript for important intellectual content: J.M.C., H.S.K. Data management, statistical analysis: M.S.K., G.U.P., S.P., J.K.L., S.Y.K., S.J.K., H.H.L. Acquisition of data, administrative, and technical support of this study: J.S.K., W.H.K. Study supervision: J.M.C., H.S.K., J.S.K., W.H.K.

Fig 1.

Figure 1.Annual colonoscopic polypectomy volume in each type of healthcare facility. The proportion of colonoscopic polypectomies performed relative to the total polypectomy volume significantly increased by 1.6% in primary facilities and decreased by 1.8% in tertiary facilities (both p<0.001) compared with the rates in the 2002 database.
Gut and Liver 2020; 14: 338-346https://doi.org/10.5009/gnl19108

Table 1 National Colonoscopy Burden over the 12-Year Period in Korea

YearTotal volumeColonoscopy without polypectomy*Colonoscopic polypectomy*In-patient polypectomy
2002264,345240,167 (90.8)24,178 (9.1)9,523 (39.4)
2003448,051408,397 (91.1)39,654 (8.9)16,016 (40.4)
2004546,190487,466 (89.2)58,724 (10.8)23,367 (39.8)
2005751,535657,790 (87.5)93,745 (12.5)35,033 (37.4)
2006957,534812,859 (84.9)144,675 (15.1)45,369 (31.4)
20071,080,359892,151 (82.6)188,208 (17.4)54,583 (29.0)
20081,207,613968,661 (80.2)238,952 (19.8)61,273 (25.6)
20091,441,5641,136,222 (78.8)305,342 (21.2)75,095 (24.6)
20101,601,6881,226,376 (76.6)375,312 (23.4)84,706 (22.6)
20111,975,2791,467,324 (74.3)507,955 (25.7)96,464 (19.0)
20122,138,1501,542,315 (72.1)595,835 (27.9)103,647 (17.4)
20132,098,8501,474,064 (70.2)624,786 (29.8)105,374 (16.9)
Percent change–2.0+2.0–2.4

Data are presented as number or number (%).

*The percent is the proportion of procedures performed each year relative to the total colonoscopy volume.


Table 2 National Colonoscopy Burden According to Sex over the 12-Year Period in Korea

YearMenWomen


Total volumeColonoscopy without polypectomy*Polypectomy*Total volumeColonoscopy without polypectomy*Polypectomy*
2002144,252127,678 (88.5)16,574 (11.5)120,093112,489 (93.7)7,604 (6.3)
2003241,827214,526 (88.7)27,301 (11.3)206,224193,871 (94.0)12,353 (6.0)
2004293,264252,753 (86.2)40,511 (13.8)252,926234,713 (92.8)18,213 (7.2)
2005408,158344,383 (84.4)63,775 (15.6)343,377313,407 (91.3)29,970 (8.7)
2006523,894426,143 (81.3)97,751 (18.7)433,640386,716 (89.2)46,924 (10.8)
2007600,398472,939 (78.8)127,459 (21.2)479,961419,212 (87.3)60,749 (12.7)
2008666,918507,257 (76.1)159,661 (23.9)540,695461,404 (85.3)79,291 (14.7)
2009792,350590,410 (74.5)201,940 (25.5)649,214545,812 (84.1)103,402 (15.9)
2010882,390634,393 (71.9)247,997 (28.1)719,298591,983 (82.3)127,315 (17.7)
20111,115,603776,992 (69.6)338,611 (30.4)859,676690,332 (80.3)169,344 (19.7)
20121,198,330804,831 (67.2)393,499 (32.8)939,820737,484 (78.5)202,336 (21.5)
20131,166,880761,413 (65.3)405,467 (34.7)931,970712,651 (76.5)219,319 (23.5)
Percent change–2.3+2.3–1.7+1.7

Data are presented as number or number (%).

*The percent is the proportion of procedures performed each year relative to the total colonoscopy volume.


Table 3 National Colonoscopy Burden According to Age Group over the 12-Year Period in Korea

YearYoung age (<50 yr)Screening age (50–74 yr)Elderly age (≥75 yr)



Total volumeCS without polypectomyPolypectomyTotal volumeCS without polypectomy*Polypectomy*Total volumeCS without polypectomy*Polypectomy*
2002131,431124,226 (94.5)7,205 (5.5)125,060109,097 (87.2)15,963 (12.8)7,8546,844 (87.1)1,010 (12.9)
2003229,271217,796 (95.0)11,475 (5.0)206,768180,233 (87.2)26,535 (12.8)12,01210,368 (86.3)1,644 (13.7)
2004267,815251,194 (93.8)16,621 (6.2)262,325222,634 (84.9)39,691 (15.1)16,05013,638 (85.0)2,412 (15.0)
2005361,729335,013 (92.6)26,716 (7.4)367,829304,638 (82.8)63,191 (17.2)21,97718,139 (82.5)3,838 (17.5)
2006442,551401,190 (90.7)41,361 (9.3)483,284386,253 (79.9)97,031 (20.1)31,69925,416 (80.2)6,283 (19.8)
2007479,373425,120 (88.7)54,253 (11.3)563,229437,513 (77.7)125,716 (22.3)37,75729,518 (78.2)8,239 (21.8)
2008508,168439,933 (86.6)68,235 (13.4)654,693494,628 (75.6)160,065 (24.4)44,75234,100 (76.2)10,652 (23.8)
2009578,202494,490 (85.5)83,712 (14.5)807,666600,228 (74.3)207,438 (25.7)55,69641,504 (74.5)14,192 (25.5)
2010588,331493,360 (83.9)94,971 (16.1)946,442684,963 (72.4)261,479 (27.6)66,91548,053 (71.8)18,862 (28.2)
2011709,141577,893 (81.5)131,248 (18.5)1,186,855834,456 (70.3)352,399 (29.7)79,28354,975 (69.3)24,308 (30.7)
2012691,351552,549 (79.9)138,802 (20.1)1,351,311926,350 (68.6)424,961 (31.4)95,48863,416 (66.4)32,072 (33.6)
2013649,927507,664 (78.1)142,263 (21.9)1,340,951896,796 (66.9)444,155 (33.1)107,97269,604 (64.5)38,368 (35.5)
Percent change–1.6+1.6–2.0+2.0–2.1+2.1

Data are presented as number or number (%).

*The percent is the proportion of procedures performed each year relative to the total colonoscopy (CS) volume.


Table 4 National Colonoscopy Burden According to Healthcare Facility Type over the 12-Year Period in Korea

YearPrimary healthcare facilitySecondary healthcare facility


Total facilityTotal CS volumeCS without polypectomy*PolypectomyTotal facilityTotal CS volumeCS without polypectomy*Polypectomy
200274197,30289,447 (91.9)7,855 (8.1)21389,07480,322 (90.2)8,752 (9.8)
2003941173,580161,535 (93.1)12,045 (6.9)307172,338155,935 (90.5)16,403 (9.5)
20041,118208,541188,736 (90.5)19,805 (9.5)454225,861200,916 (89.0)24,945 (11.0)
20051,281286,832252,915 (88.2)33,917 (11.8)571328,030286,629 (87.4)41,401 (12.6)
20061,508367,715312,673 (85.0)55,042 (15.0)660425,631361,774 (85.0)63,857 (15.0)
20071,635420,900346,348 (82.3)74,552 (17.7)717481,575397,277 (82.5)84,298 (17.5)
20081,791479,126380,046 (79.3)99,080 (20.7)809538,892433,290 (80.4)105,602 (19.6)
20091,894584,781452,727 (77.4)132,054 (22.6)856627,587499,776 (79.6)127,811 (20.4)
20102,040664,000497,557 (74.9)166,443 (25.1)908696,670539,123 (77.4)157,547 (22.6)
20112,221862,130627,247 (72.8)234,883 (27.2)950857,009642,009 (74.9)215,000 (25.1)
20122,316938,075661,358 (70.5)276,717 (29.5)992923,782671,683 (72.7)252,099 (27.3)
20132,408918,035626,622 (68.3)291,413 (31.7)1,020916,029648,732 (70.8)267,297 (29.2)
Percent change–2.4+2.4–1.9+1.9

YearTertiary healthcare facilityOther healthcare facility

Total facilityTotal CS volumeCS without polypectomy*PolypectomyTotal facilityTotal CS volumeCS without polypectomy*Polypectomy

20024177,96970,398 (90.3)7,571 (9.7)000 (0.0)0 (0.0)
200342102,12690,921 (89.0)11,205 (11.0)176 (85.7)1 (14.3)
200443111,64897,691 (87.5)13,957 (12.5)5140123 (87.9)17 (12.1)
200541136,467118,046 (86.5)18,421 (13.5)14206200 (97.1)6 (2.9)
200643163,608137,889 (84.3)25,719 (15.7)18580523 (90.2)57 (9.8)
200745176,816147,695 (83.5)29,121 (16.5)281,068831 (77.8)237 (22.2)
200848188,401154,408 (82.0)33,993 (18.0)531,194917 (76.8)277 (23.2)
200944227,388182,176 (80.1)45,212 (19.9)691,8081,543 (85.3)265 (14.7)
201044238,498187,558 (78.6)50,940 (21.4)842,5202,138 (84.8)382 (15.2)
201145252,192194,992 (77.3)57,200 (22.7)973,9483,076 (77.9)872 (22.1)
201247269,869204,870 (75.9)64,999 (24.1)1276,4244,404 (68.6)2,020 (31.4)
201345259,116194,901 (75.2)64,215 (24.8)1365,6703,809 (67.2)1,861 (32.8)
Percent change–1.4+1.4

Data are presented as number or number (%).

*The percent is the proportion of procedures performed each year relative to the total colonoscopy (CS) volume.


Table 5 Colonoscopy Burden of HVFs over the 12-Year Period in Korea

YearPrimary facilitySecondary facilityTertiary facility



Total facilityHVFTotal CS volumeCS by HVFTotal facilityHVFTotal CS volumeCS by HVFTotal facilityHVFTotal CS volumeCS by HVF
2002741138 (18.6)97,30265,532 (67.3)21378 (36.6)89,07481,441 (91.4)4138 (92.7)77,96977,607 (99.5)
2003941241 (25.6)173,580128,733 (74.2)307146 (47.6)172,338162,967 (94.6)4242 (100.0)102,126102,126 (100.0)
20041,118310 (27.7)208,541159,744 (76.6)454195 (43.0)225,861209,954 (93.0)4342 (97.7)111,648111,646 (100.0)
20051,281405 (31.6)286,832230,342 (80.3)571273 (47.8)328,030309,221 (94.3)4141 (100.0)136,467136,467 (100.0)
20061,508497 (33.0)367,715302,222 (82.2)660363 (55.0)425,631407,472 (95.7)4342 (97.7)163,608163,599 (100.0)
20071,635555 (33.9)420,900349,481 (83.0)717371 (51.7)481,575457,269 (95.0)4542 (93.3)176,816176,812 (100.0)
20081,791623 (34.8)479,126400,216 (83.5)809418 (51.7)538,892511,956 (95.0)4843 (89.6)188,401188,372 (100.0)
20091,894737 (38.9)584,781505,555 (86.5)856489 (57.1)627,587602,607 (96.0)4443 (97.7)227,388227,319 (100.0)
20102,040824 (40.4)664,000578,234 (87.1)908518 (57.0)696,670668,812 (96.0)4443 (97.7)238,498238,482 (100.0)
20112,2211,030 (46.4)862,130771,774 (89.5)950588 (61.9)857,009830,944 (97.0)4543 (95.6)252,192252,177 (100.0)
20122,3161,113 (48.1)938,075847,351 (90.3)992613 (61.8)923,782896,816 (97.1)4746 (97.9)269,869269,704 (99.9)
20132,4081,113 (46.2)918,035820,108 (89.3)1,020613 (60.1)916,029887,043 (96.8)4544 (97.8)259,116259,115 (100.0)
Percent change+2.8+1.7+2.0+0.3+0.0+0.0

Data are presented as number or number (%). A high volume facility (HVF) was defined as a facility with an annual colonoscopy (CS) volume of more than 200 colonoscopies.


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Gut and Liver

Vol.18 No.3
May, 2024

pISSN 1976-2283
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