Cholecystitis and cholangiocarcinoma: a two-sample mendelian randomization study

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Epidemiological studies suggest that cholecystitis elevates the risk of hepatobiliary cancer. However, an independent causal relationship remains unrevealed. Observational studies are vulnerable to residual confounders and bias, which compromises causal inference. Our study aimed to evaluate whether cholecystitis is an independent risk factor for cholangiocarcinoma. Methods Instrument variables were identified as independent single nucleotide polymorphisms highly associated with cholecystitis (n = 62). The entire dataset from the Integrative Epidemiology Unit (IEU) public availability genome-wide association studies was utilized to determine outcomes for cholangiocarcinoma (n = 62). In this study, five Mendelian randomization (MR) statistical techniques (Inverse Variance Weighted, MR Egger, Weighted Median, Simple Mode, and Weighted mode) were used. The MR Egger intercept test, leave-one-out analysis, and the funnel plot were all utilized in sensitivity analyses. Results Results of the Inverse Variance Weighted tests genetically predicted that cholecystitis was significantly associated with higher risk of cholangiocarcinoma, with an odds ratio of 1.27 (95% CI: 1.038–1.553; P = 0.02). But the Weighted Median Method, MR Egger Regression, Simple Mode, and Weighted Mode all showed no statistical significance (P > 0.05). Both funnel plots and MR Egger intercepts indicated the absence of any directional pleiotropic effects between cholecystitis and cholangiocarcinoma. Conclusion We found potential evidence of a causal effect between cholecystitis and cholangiocarcinoma, indicating an increased likelihood of cholangiocarcinoma in patients with cholecystitis through mendelian randomization analysis. Our results excepted enhance the management of patients with cholecystitis to decrease the risk of cholangiocarcinoma. Cholecystitis cholangiocarcinoma mendelian randomization analysis Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 1. Introduction Cholangiocarcinoma, a rare malignancy affecting the bile ducts, represents a mere 2% of all malignancies 1 . Despite its low incidence, its grim prognosis is largely attributed to a weak response to chemotherapeutics. Radical surgery stands as the sole effective treatment, yet its application is often limited due to late diagnoses. 2 . Hence, active prevention, early detection, and swift treatment of cholangiocarcinoma are imperative. Identification of potential risk factors is paramount as it aids surgeons in detecting early-stage cholangiocarcinoma. Parasitic infections, primary sclerosing cholangitis, and biliary duct cysts are among the various risk factors observed in clinical settings. 3 . Additionally, age emerges as a notable risk factor, prevalent among most patients 1 , 2 . Cholecystitis, characterized by inflammation of the gallbladder, typically arises from obstruction of the cystic duct 4 . Previous research has established associations between cholecystitis and various conditions, such as gallstones, gallstone pancreatitis, and choledocholithiasis 5 – 7 . Diagnostic procedures commonly employed for cholecystitis patients encompass ultrasonography of the right upper quadrant and hepatobiliary scintigraphy 8 . Emerging studies suggest a potential link between cholecystitis and the development of cholangiocarcinoma 9 – 11 (Fig. 1). Furthermore, several randomized controlled trials provide evidence supporting the notion that cholecystitis may heighten the risk of cholangiocarcinoma 12 , 13 . While randomized controlled trials typically serve to mitigate confounding factors, instances of reverse causality may still affect the causal relationship between exposure and outcome. Moreover, challenges in execution, high input costs, occasional impracticality, and ethical concerns have restricted their widespread adoption. Currently, researchers are actively pursuing the development of more precise testing methodologies. One promising avenue for addressing this limitation is Mendelian randomization (MR) analysis 14 . MR presents an alternative approach to mitigating observational biases 15 , 16 . It employs genetic instrumental variables to substitute for exposures that could otherwise be confounded or subject to reverse causation 14 . As these genetic variants are typically uncorrelated with confounders, differences in outcomes between variant carriers and non-carriers can be attributed to variations in risk factors or disease susceptibility. Consequently, MR provides a robust means to comprehend the impact of modifiable exposures on the trait of interest, in contrast to traditional observational studies susceptible to confounding or reverse causation 17 . For example, previous MR analyses have suggested that several factors, including gallstones and liver fat accumulation, represent independent risk factors for cholangiocarcinoma 18 . However, conclusive evidence from randomized controlled trials regarding the association between cholelithiasis and cholangiocarcinoma remains elusive. A definitive causal relationship between cholelithiasis and cholangiocarcinoma has yet to be established. Based on the above, we combined data from a published genome-wide association studies (GWAS) and first investigated the potential causal relationship between cholecystitis and cholangiocarcinoma risk through MR analysis. 2. Materials and methods 2.1 Data sources We conducted a two-sample MR analysis employing summary statistics from GWAS to explore the causal relationship between cholecystitis and cholangiocarcinoma. Our study utilized pooled GWAS data from the IEU, publicly accessible at https://gwas.mrcieu.ac.uk/ , without requiring access through the IEU platform. Specifically, the genetic instrument employed in this investigation was derived from recent GWAS pooled data on biliary tract disease. Our MR analysis adhered to three instrumental variable assumptions 19 . Firstly, the relevance assumption was met by selecting genetic variants strongly associated with cholangiocarcinoma at the genome-wide significance level (P < 5×10 − 6 ). Secondly, the independence assumption was ensured by confirming that the selected genetic variants were not correlated with any other potential factors linked to cholangiocarcinoma and cholecystitis. Lastly, the exclusion-restriction assumption was fulfilled by establishing a significance threshold at the genome-wide level (P < 5×10 − 6 ) and stipulating that the genetic variants were unrelated to cholangiocarcinoma apart from through cholecystitis 20 . 2.2 Instrumental variables SNPs associated with cholecystitis were identified based on a stringent significance threshold (P < 5×10 − 6 ). Subsequently, we utilized linkage disequilibrium (LD, R 2 ≤ 0.001) to evaluate gene linkage among these SNPs, ensuring a genetic distance of less than 5000 kb 16 . Detailed information including major alleles, allele frequencies, β-values, p-values, and standard errors (SEs) for each single nucleotide polymorphism (SNP) was collected. Previous MR studies have underscored the importance of strong correlation between instrumental variables and exposure, with F-statistics exceeding 10 serving as a robust criterion 21 . SNPs associated with the exposure were deliberately excluded from the cholangiocarcinoma GWAS. To uphold the third assumption, which posits that genetic variants influence the outcome solely through the intermediary risk factor, SNPs directly linked to cholecystitis were removed using a threshold of genome-wide significance (P < 5×10 − 6 ), as in previous studies. Additionally, F-statistics were computed, and weak instrumental variables (F < 10) were systematically excluded from the analysis. 2.3 Statistical analyses We conducted two-sample Mendelian randomization analyses to elucidate the relationship between cholecystitis and the risk of cholangiocarcinomas using genetic instruments. Specifically, we downloaded the latest data from the GWAS pooled data available on the IEU platform to estimate the association between a genetic instrument and cholangiocarcinoma. In this study, we employed a variety of methods, including inverse variance weighted (IVW), MR Egger, weighted median, simple mode, and weighted mode, to analyze the causal relationship between cholecystitis and cholangiocarcinoma, thereby assessing the potential influence of variation heterogeneity and pleiotropy 16 , 22 . As the primary Mendelian randomization method, the IVW approach integrates per-SNP effects along with a slope estimate, calculated as the weighted regression slope of SNP-outcome effects on SNP-exposure effects, with a zero intercept 23 , 24 . IVW assumes all genetic variants are valid and typically exhibits the highest statistical power among the methods considered 25 . Consequently, we utilized the IVW method as the primary approach in our study to explore initial associations between cholecystitis and hepatic bile duct malignancies. The MR Egger intercept test served to assess the presence of horizontal pleiotropy, with a non-significant P-value (> 0.05) indicating no heterogeneity among the instrumental variables 26 . Lower probabilities of horizontal pleiotropy signify less significant pleiotropic effects, suggesting that the SNP is primarily associated with the exposure rather than with other confounding variables 27 . The weighted median method calculates the estimated weighted median of the causal relationship between SNPs, assuming that at least half of the instrumental variables complement IVW are valid 28 . Additionally, we conducted leave-one-out analysis to assess the consistency of results and identify any single SNP exerting a disproportionate influence 29 . Finally, a funnel plot was employed to examine the potential directionality of pleiotropy 30 . In this study, all analyses were conducted using Two-Sample MR software (version 0.5.6) and R software (version 4.2.1). The significance threshold for the tests was set based on the p-value. If the p-value exceeded 0.05, the presence of pleiotropy in the causal analysis was considered minimal or non-existent, and its influence was deemed negligible. 3. Results Causal effects of cholecystitis on hepatic bile duct cancer In the two-way Mendelian randomization analysis, 62 SNPs were extracted with cholecystitis as the exposure and cholangiocarcinoma as the outcome. The IVW analysis showed an increased risk of cholangiocarcinoma in cholecystitis patients (OR = 1.270, 95% CI = 1.038–1.553, P = 0.020). However, MR Egger, weighted median method, simple mode, and weighted mode provided more conservative suggesting that there may not be a significant association between the presence of cholecystitis and an increased risk of cholangiocarcinoma (MR Egger: OR = 1.282, 95% CI = 0.755–2.177, P = 0.361; weighted median: OR = 1.155, 95% CI = 0.915–1.460, P = 0.226; simple mode: OR = 1.362, 95% CI = 0.815–2.274, P = 0.243; weighted mode: OR = 1.110, 95% CI: 0.783–1.574, P = 0.561) (Table 1 and Fig. 2). Table 1 Presents the MR estimates for assessing the causal effect of cholecystitis on the risk of cholangiocarcinoma 1 . MR method Number of SNPs Beat SE Association p-value Odds ratio 95% confidence interval IVW 62 0.239 0.103 0.020 1.270 1.038–1.553 MR Egger 62 0.248 0.270 0.361 1.282 0.755–2.177 Weighted median 62 0.144 0.119 0.226 1.155 0.915–1.460 Simple mode 62 0.309 0.262 0.243 1.362 0.815–2.274 Weighted mode 62 0.104 0.178 0.561 1.110 0.783–1.574 MR, Mendelian randomization; IVW, Inverse Variance Weighted; SNP, Single nucleotide polymorphism; SE, Standard error. Scatter plots of SNP effect sizes for cholecystitis and cholangiocarcinoma are shown in Fig. 3. The study findings indicate that the estimated causal effects of cholangiocarcinoma were highly consistent across IVW, MR Egger, weighted median, simple mode, and weighted modes for cholecystitis. Cholelithiasis is a risk factor for cholangiocarcinoma, although the significance varied among different studies. In this study, we extracted 62 cholecystitis-related SNPs as instrumental variables (R 2 < 0.001, P < 5×10 − 6 ) from the GWAS study. The impact of each SNP locus on cholangiocarcinoma. Furthermore, we also conducted leave-one-SNP-out analyses to identify the effect of each SNP on the overall causal estimates. No significant differences in the estimated causal effects were observed when we removed individual SNPs from our MR analysis one by one. Consequently, the estimated effect cannot be explained by any single SNP (Fig. 4). Funnel plots revealed that the Wald ratio of each SNP plotted was inversely related to their accuracy. The approximate symmetry indicated that the gene does not exhibit significant heterogeneity, and there is no systematic deviation between the research effect and its accuracy. Our results show that cholelithiasis is a risk factor for cholangiocarcinoma without significant heterogeneity (Fig. 5). 4. Discussion This study represents the pioneering effort to systematically evaluate the causal link between genetic susceptibility to cholecystitis and the incidence of cholangiocarcinoma. Our findings elucidate that genetically predicted cholecystitis correlates with heightened risk of cholangiocarcinoma. This positive association between the two conditions was robustly affirmed through sensitivity analyses. Overall, our Mendelian randomization investigation underscores a causal, unidirectional relationship between cholecystitis and the susceptibility to cholangiocarcinoma, indicating an elevated risk of cholangiocarcinoma among individuals with cholecystitis. Previous research has elucidated the intricate interplay between chronic inflammation of the intrahepatic bile duct and the pathogenesis of cholangiocarcinoma. This chronic inflammatory milieu triggers abnormal hyperplasia of the bile duct endothelium and glandular mucosal epithelium. Additionally, factors such as altered bile composition, cholestasis, and metabolic conditions contribute to the progressive damage of the bile duct endothelium and mucosal epithelium, including glandular structures. This cascade of events culminates in a spectrum of changes ranging from hyperplasia and metaplasia to atypical hyperplasia, eventually progressing to cancerous transformation 31 – 33 . Cholecystitis, a common inflammatory condition affecting the gallbladder, has been identified as a significant risk factor for the development of cholangiocarcinoma. A population-based case-control study conducted by Chang et al. highlighted various factors associated with an elevated risk of cholangiocarcinoma, including cholangitis, cholelithiasis, cholecystitis, cirrhosis of the liver, alcoholic liver disease, chronic non-alcoholic liver disease, diabetes, chronic pancreatitis, inflammatory bowel disease, and peptic ulcer 11 . Furthermore, a systematic review and meta-analysis underscored a substantially heightened risk of cholangiocarcinoma in patients with cholangitis (OR: 6.3, 95% CI: 2.3–17.5) 32 . In line with these observational findings, our study unveils a novel insight into the genetic underpinnings of cholecystitis and its causal relationship with cholangiocarcinoma. Utilizing rigorous Mendelian randomization methods including the IVW method, MR Egger regression, and the weighted median method, we observed a 27.00% increased risk of cholangiocarcinoma associated with genetic predisposition to cholecystitis. These robust findings further support the notion that cholecystitis may indeed heighten the risk of cholangiocarcinoma, as indicated by collective evidence from observational studies. To reveal the intricate relationship between cholecystitis and cholangiocarcinoma development, it is essential to first consider a wide array of preventive measures, diagnostic techniques, and therapeutic strategies tailored for managing cholecystitis. Our primary investigation, meticulously incorporating genetic testing at a stringent significance threshold of P < 5×10 − 8 , has provided compelling evidence bolstering the hypothesis that heightened genetic susceptibility to cholecystitis correlates with an elevated risk of cholangiocarcinoma. This pivotal finding underscores the potential role of genetic factors in predisposing individuals to both conditions, offering valuable insights into the underlying molecular mechanisms and potential avenues for targeted intervention and precision medicine approaches. The MR method offers a robust approach for assessing causality by establishing a link between an "exposure" and an "outcome," thereby mitigating the risk of confounding inherent in traditional observational studies. While observational studies are frequently relied upon to infer causality, they can be time-consuming and impractical. It is noteworthy that gallstones are implicated in 80–95% of acute cholecystitis cases, with acalculous cholecystitis comprising the remaining 5–10% of cases 34 , 35 . However, many studies predominantly focus on the impact of gallstones, overlooking the significant contribution of cholecystitis itself. In our study, we conducted a two-sample MR analysis, which revealed a causal relationship from cholecystitis to cholangiocarcinoma. Our findings underscore the critical importance of initiating treatment promptly following cholecystitis diagnosis to optimize clinical outcomes and mitigate potential complications, such as cholangiocarcinoma. Furthermore, we advocate for early screening for cholangiocarcinoma risk among cholecystitis patients, as this proactive approach may facilitate earlier diagnosis and timely initiation of curative interventions for cholangiocarcinoma. Overall, our systematic meta-analysis, conducted in a large population of European ancestry, sheds light on the relationship between cholecystitis and cholangiocarcinoma, offering valuable insights for informing preventive care strategies for cholangiocarcinoma and identifying pivotal intervention points for managing cholangiocarcinoma in patients with cholecystitis. Our study delved into the causal association between cholangiocarcinoma and cholecystitis, guided by earlier research highlighting chronic inflammation as the primary driver of progression from cholecystitis to cholangiocarcinoma. This chronic inflammatory milieu can trigger a cascade of events, including epigenetic alterations, activation of proto-oncogenes, and deactivation of tumor suppressor genes, culminating in abnormal cell proliferation, differentiation, and an elevated cancer risk. For instance, an inflammatory microenvironment characterized by elevated levels of pro-inflammatory cytokines, growth factors, and toxic bile acids may foster accelerated mitosis of normal bile duct cells, predisposing them to mutations and uncontrolled proliferation. Epigenetic modifications in intrahepatic cholangiocarcinoma epithelial cells can be induced by pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and transforming growth factor-β (TGF-β), akin to tumor suppressor inactivation and oncogene activation mechanisms 36 , 37 . Of particular interest, IL-6, upon binding to the gp130 receptor, triggers JAK1/2 activation, leading to subsequent STAT3 phosphorylation and activation. This signaling cascade may also activate extracellular signal-regulated kinase 1/2 (ERK1/2) and p38/MAPK pathways, ultimately fueling tumor proliferation and cholangiocarcinoma progression 38 . Future studies should endeavor to explore additional potential mechanistic pathways to inform the development of pertinent clinical recommendations in the management of cholecystitis-associated cholangiocarcinoma. It's important to recognize limitations in our study. The biological mechanisms of cholecystitis and cholangiocarcinoma are complex, involving many factors. Using certain genetic markers with unclear roles in Mendelian randomization may challenge our assumptions. Also, genetic differences can vary among ethnic groups. While our study focused on one population, more research on diverse populations is needed for stronger evidence. Additionally, we should conduct formal mediation analysis to understand how cholecystitis might lead to cholangiocarcinoma. Cholangiocarcinoma patients show diverse characteristics, suggesting cholecystitis could be linked to specific subtypes. Future studies should explore these subgroups further to better understand the relationships. In conclusion, this study strengthened the argument for a genetic connection between susceptibility to cholecystitis and cholangiocarcinoma. Considering the high mortality and poor prognosis associated with cholangiocarcinoma patients, it is important to identify and manage the risk factor of cholecystitis for cholangiocarcinoma to reduce its morbidity. Abbreviations IEU Integrative Epidemiology Unit MR Mendelian randomization GWAS Genome-wide association studies SEs Standard errors SNP Single nucleotide polymorphism IVW Inverse variance weighted TNF-α Tumor necrosis factor-α IL-6 Interleukin-6 TGF-β Transforming growth factor-β ERK1/2 Extracellular signal-regulated kinase 1/2. Declarations Ethics approval and consent to participate Not applicable Consent for publication Not applicable Availability of data and materials Publicly available datasets were analyzed in this study. Our study utilized pooled GWAS data from the IEU, publicly accessible at https://gwas.mrcieu.ac.uk/. Competing interests The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Funding This research was funded by Cuiying Scientific and Technological Innovation Program of Lanzhou University Second Hospital-CY2022-MS-A18, Major Science and Technology Project of Gansu Province [20ZD7FA003, 22ZD6FA050, 22JR9KA002] and Natural Science Foundation of Gansu Province (21JR1RA135, 23JRRA1001). Author contributions XG: Writing—original draft preparation, investigation, and figure preparation. HG: Investigation, figure preparation and analyzed the data. SW: Investigation. FT: Investigation. YZ: Investigation. YL: Conceptualization, methodology, and supervision. All authors contributed to the article and approved the submitted version. Acknowledgements Not applicable References Khan AS, Dageforde LA, Cholangiocarcinoma. 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Gastroenterol Clin North Am . 2010;39(2):265 – 87, ix. 10.1016/j.gtc.2010.02.009 . Moeini A, Haber PK, Sia D. Cell of origin in biliary tract cancers and clinical implications. JHEP Rep Apr. 2021;3(2):100226. 10.1016/j.jhepr.2021.100226 . Banales JM, Marin JJG, Lamarca A, et al. Cholangiocarcinoma 2020: the next horizon in mechanisms and management. Nat Rev Gastroenterol Hepatol Sep. 2020;17(9):557–88. 10.1038/s41575-020-0310-z . Brindley PJ, Bachini M, Ilyas SI, et al. Cholangiocarcinoma. Nat Rev Dis Primers Sep. 2021;9(1):65. 10.1038/s41572-021-00300-2 . Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 26 Aug, 2025 Read the published version in BMC Gastroenterology → Version 1 posted Editorial decision: Revision requested 28 May, 2024 Submission checks completed at journal 24 May, 2024 Editor assigned by journal 24 May, 2024 First submitted to journal 24 May, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4470063","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":307733926,"identity":"0093f39c-ad2a-47ec-a3b6-3fd03ae83dbb","order_by":0,"name":"Xing Gao","email":"","orcid":"","institution":"School of Life Sciences of Lanzhou University","correspondingAuthor":false,"prefix":"","firstName":"Xing","middleName":"","lastName":"Gao","suffix":""},{"id":307733927,"identity":"8713e4f7-37cc-4e95-ac17-1f95c1153246","order_by":1,"name":"Hao Gao","email":"","orcid":"","institution":"School of Life Sciences of Lanzhou University","correspondingAuthor":false,"prefix":"","firstName":"Hao","middleName":"","lastName":"Gao","suffix":""},{"id":307733928,"identity":"79fe7d3e-6435-4d44-9a86-7110d548af18","order_by":2,"name":"Song Wang","email":"","orcid":"","institution":"National-Local Joint Engineering Research Center of Biodiagnosis \u0026 Biotherapy, The Second Affiliated Hospital, Xi'an Jiaotong University","correspondingAuthor":false,"prefix":"","firstName":"Song","middleName":"","lastName":"Wang","suffix":""},{"id":307733929,"identity":"b7a78aa3-b1d4-4691-9a8c-83fd13b84730","order_by":3,"name":"Futian Tang","email":"","orcid":"","institution":"Key Laboratory of the Digestive System Tumors of Gansu Province, The Second Clinical Medical College of Lanzhou Universit","correspondingAuthor":false,"prefix":"","firstName":"Futian","middleName":"","lastName":"Tang","suffix":""},{"id":307733930,"identity":"dc02fe03-51ee-4756-870f-6d850cd44e22","order_by":4,"name":"Yang Zhao","email":"","orcid":"","institution":"Key Laboratory of the Digestive System Tumors of Gansu Province, The Second Clinical Medical College of Lanzhou Universit","correspondingAuthor":false,"prefix":"","firstName":"Yang","middleName":"","lastName":"Zhao","suffix":""},{"id":307733931,"identity":"475b5735-c091-415a-962e-4a23b639ea31","order_by":5,"name":"Yumin Li","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAq0lEQVRIiWNgGAWjYBACPmYg8aEAzDYgTgsbUAvjDAOStAAxMw9pWth5TDfbGNQlNrA3b5NgqLlDjMN4zG7nGLAlNvAcK5NgOPaMaC08iQ0SOWYSjA2HidRiYSCR2CD/hhQtDAYGQFt4iNbCVnazxyDBuI0nrdgi4RgRWvj5D2+78aOiTraf/fDGGx9qiNDCwMABiQ5QBDEkEKOBgYH9AXHqRsEoGAWjYOQCAB+aLZkLPadHAAAAAElFTkSuQmCC","orcid":"","institution":"Key Laboratory of the Digestive System Tumors of Gansu Province, The Second Clinical Medical College of Lanzhou Universit","correspondingAuthor":true,"prefix":"","firstName":"Yumin","middleName":"","lastName":"Li","suffix":""}],"badges":[],"createdAt":"2024-05-24 05:08:32","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4470063/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4470063/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12876-025-04199-x","type":"published","date":"2025-08-26T15:57:23+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":58077473,"identity":"84bbf461-2888-4241-9c4e-403d19614689","added_by":"auto","created_at":"2024-06-10 22:33:53","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":226977,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic diagram of cholecystitis and cholangiocarcinoma.\u003c/p\u003e","description":"","filename":"fig1.png","url":"https://assets-eu.researchsquare.com/files/rs-4470063/v1/edb3fddeab6184dc954388cc.png"},{"id":58077716,"identity":"864f7a0a-c698-4d0c-a708-93b76adb21ba","added_by":"auto","created_at":"2024-06-10 22:41:53","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":240466,"visible":true,"origin":"","legend":"\u003cp\u003eEstimates of Mendelian randomization for the association between genetically instrumented cholecystitis and cholangiocarcinoma.\u003c/p\u003e","description":"","filename":"fig2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-4470063/v1/ec485db03c40f43cb36181d1.jpeg"},{"id":58077477,"identity":"882a1657-5fea-4b8c-89c5-0ffae2dcaf61","added_by":"auto","created_at":"2024-06-10 22:33:53","extension":"jpeg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":288511,"visible":true,"origin":"","legend":"\u003cp\u003eScatter plot illustrating the causal effect of cholecystitis on the risk of cholangiocarcinoma. The slope of the straight line represents the strength of the causal relationship.\u003c/p\u003e","description":"","filename":"fig3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-4470063/v1/4d311268a9931c69689127dd.jpeg"},{"id":58077822,"identity":"a72eda0b-65bb-463d-9d7b-66346e8dcb43","added_by":"auto","created_at":"2024-06-10 22:49:53","extension":"jpeg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":717367,"visible":true,"origin":"","legend":"\u003cp\u003eForest plots depicting the causal effects of SNPs associated with cholangiocarcinoma on cholecystitis.\u003c/p\u003e","description":"","filename":"fig4.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-4470063/v1/04a3618cfbf42908ed245a18.jpeg"},{"id":58077475,"identity":"232d80b6-2066-4ee9-b2f6-3386f1b7995f","added_by":"auto","created_at":"2024-06-10 22:33:53","extension":"jpeg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":200373,"visible":true,"origin":"","legend":"\u003cp\u003eFunnel plots are used to visualize the overall heterogeneity of MR estimates for the effect of cholecystitis on the risk of cholangiocarcinoma.\u003c/p\u003e","description":"","filename":"fig5.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-4470063/v1/226ab805074260a6cdbf6be9.jpeg"},{"id":90344971,"identity":"21f58399-fb8e-42f2-aba8-ef35463a3286","added_by":"auto","created_at":"2025-09-01 16:08:37","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2257850,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4470063/v1/a31e43ed-6df4-459f-8101-406d91d45848.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Cholecystitis and cholangiocarcinoma: a two-sample mendelian randomization study","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eCholangiocarcinoma, a rare malignancy affecting the bile ducts, represents a mere 2% of all malignancies\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e. Despite its low incidence, its grim prognosis is largely attributed to a weak response to chemotherapeutics. Radical surgery stands as the sole effective treatment, yet its application is often limited due to late diagnoses.\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e. Hence, active prevention, early detection, and swift treatment of cholangiocarcinoma are imperative. Identification of potential risk factors is paramount as it aids surgeons in detecting early-stage cholangiocarcinoma. Parasitic infections, primary sclerosing cholangitis, and biliary duct cysts are among the various risk factors observed in clinical settings. \u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e. Additionally, age emerges as a notable risk factor, prevalent among most patients\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e,\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eCholecystitis, characterized by inflammation of the gallbladder, typically arises from obstruction of the cystic duct\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e. Previous research has established associations between cholecystitis and various conditions, such as gallstones, gallstone pancreatitis, and choledocholithiasis\u003csup\u003e\u003cspan additionalcitationids=\"CR6\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e. Diagnostic procedures commonly employed for cholecystitis patients encompass ultrasonography of the right upper quadrant and hepatobiliary scintigraphy\u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e. Emerging studies suggest a potential link between cholecystitis and the development of cholangiocarcinoma\u003csup\u003e\u003cspan additionalcitationids=\"CR10\" citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e (Fig.\u0026nbsp;1). Furthermore, several randomized controlled trials provide evidence supporting the notion that cholecystitis may heighten the risk of cholangiocarcinoma\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e,\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eWhile randomized controlled trials typically serve to mitigate confounding factors, instances of reverse causality may still affect the causal relationship between exposure and outcome. Moreover, challenges in execution, high input costs, occasional impracticality, and ethical concerns have restricted their widespread adoption. Currently, researchers are actively pursuing the development of more precise testing methodologies. One promising avenue for addressing this limitation is Mendelian randomization (MR) analysis\u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e. MR presents an alternative approach to mitigating observational biases \u003csup\u003e\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e,\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e. It employs genetic instrumental variables to substitute for exposures that could otherwise be confounded or subject to reverse causation\u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e. As these genetic variants are typically uncorrelated with confounders, differences in outcomes between variant carriers and non-carriers can be attributed to variations in risk factors or disease susceptibility. Consequently, MR provides a robust means to comprehend the impact of modifiable exposures on the trait of interest, in contrast to traditional observational studies susceptible to confounding or reverse causation\u003csup\u003e\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u003c/sup\u003e. For example, previous MR analyses have suggested that several factors, including gallstones and liver fat accumulation, represent independent risk factors for cholangiocarcinoma\u003csup\u003e\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e. However, conclusive evidence from randomized controlled trials regarding the association between cholelithiasis and cholangiocarcinoma remains elusive. A definitive causal relationship between cholelithiasis and cholangiocarcinoma has yet to be established.\u003c/p\u003e \u003cp\u003eBased on the above, we combined data from a published genome-wide association studies (GWAS) and first investigated the potential causal relationship between cholecystitis and cholangiocarcinoma risk through MR analysis.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"2. Materials and methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1 Data sources\u003c/h2\u003e \u003cp\u003eWe conducted a two-sample MR analysis employing summary statistics from GWAS to explore the causal relationship between cholecystitis and cholangiocarcinoma. Our study utilized pooled GWAS data from the IEU, publicly accessible at \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://gwas.mrcieu.ac.uk/\u003c/span\u003e\u003cspan address=\"https://gwas.mrcieu.ac.uk/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e, without requiring access through the IEU platform. Specifically, the genetic instrument employed in this investigation was derived from recent GWAS pooled data on biliary tract disease. Our MR analysis adhered to three instrumental variable assumptions\u003csup\u003e\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u003c/sup\u003e. Firstly, the relevance assumption was met by selecting genetic variants strongly associated with cholangiocarcinoma at the genome-wide significance level (P\u0026thinsp;\u0026lt;\u0026thinsp;5\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e). Secondly, the independence assumption was ensured by confirming that the selected genetic variants were not correlated with any other potential factors linked to cholangiocarcinoma and cholecystitis. Lastly, the exclusion-restriction assumption was fulfilled by establishing a significance threshold at the genome-wide level (P\u0026thinsp;\u0026lt;\u0026thinsp;5\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e) and stipulating that the genetic variants were unrelated to cholangiocarcinoma apart from through cholecystitis\u003csup\u003e\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2 Instrumental variables\u003c/h2\u003e \u003cp\u003eSNPs associated with cholecystitis were identified based on a stringent significance threshold (P\u0026thinsp;\u0026lt;\u0026thinsp;5\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e). Subsequently, we utilized linkage disequilibrium (LD, R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;\u0026le;\u0026thinsp;0.001) to evaluate gene linkage among these SNPs, ensuring a genetic distance of less than 5000 kb\u003csup\u003e\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e. Detailed information including major alleles, allele frequencies, β-values, p-values, and standard errors (SEs) for each single nucleotide polymorphism (SNP) was collected. Previous MR studies have underscored the importance of strong correlation between instrumental variables and exposure, with F-statistics exceeding 10 serving as a robust criterion\u003csup\u003e\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eSNPs associated with the exposure were deliberately excluded from the cholangiocarcinoma GWAS. To uphold the third assumption, which posits that genetic variants influence the outcome solely through the intermediary risk factor, SNPs directly linked to cholecystitis were removed using a threshold of genome-wide significance (P\u0026thinsp;\u0026lt;\u0026thinsp;5\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e), as in previous studies. Additionally, F-statistics were computed, and weak instrumental variables (F\u0026thinsp;\u0026lt;\u0026thinsp;10) were systematically excluded from the analysis.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.3 Statistical analyses\u003c/h2\u003e \u003cp\u003eWe conducted two-sample Mendelian randomization analyses to elucidate the relationship between cholecystitis and the risk of cholangiocarcinomas using genetic instruments. Specifically, we downloaded the latest data from the GWAS pooled data available on the IEU platform to estimate the association between a genetic instrument and cholangiocarcinoma. In this study, we employed a variety of methods, including inverse variance weighted (IVW), MR Egger, weighted median, simple mode, and weighted mode, to analyze the causal relationship between cholecystitis and cholangiocarcinoma, thereby assessing the potential influence of variation heterogeneity and pleiotropy\u003csup\u003e\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e,\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eAs the primary Mendelian randomization method, the IVW approach integrates per-SNP effects along with a slope estimate, calculated as the weighted regression slope of SNP-outcome effects on SNP-exposure effects, with a zero intercept\u003csup\u003e\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e,\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e\u003c/sup\u003e. IVW assumes all genetic variants are valid and typically exhibits the highest statistical power among the methods considered\u003csup\u003e\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u003c/sup\u003e. Consequently, we utilized the IVW method as the primary approach in our study to explore initial associations between cholecystitis and hepatic bile duct malignancies.\u003c/p\u003e \u003cp\u003eThe MR Egger intercept test served to assess the presence of horizontal pleiotropy, with a non-significant P-value (\u0026gt;\u0026thinsp;0.05) indicating no heterogeneity among the instrumental variables\u003csup\u003e\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u003c/sup\u003e. Lower probabilities of horizontal pleiotropy signify less significant pleiotropic effects, suggesting that the SNP is primarily associated with the exposure rather than with other confounding variables\u003csup\u003e\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u003c/sup\u003e. The weighted median method calculates the estimated weighted median of the causal relationship between SNPs, assuming that at least half of the instrumental variables complement IVW are valid\u003csup\u003e\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e\u003c/sup\u003e. Additionally, we conducted leave-one-out analysis to assess the consistency of results and identify any single SNP exerting a disproportionate influence\u003csup\u003e\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e\u003c/sup\u003e. Finally, a funnel plot was employed to examine the potential directionality of pleiotropy\u003csup\u003e\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eIn this study, all analyses were conducted using Two-Sample MR software (version 0.5.6) and R software (version 4.2.1). The significance threshold for the tests was set based on the p-value. If the p-value exceeded 0.05, the presence of pleiotropy in the causal analysis was considered minimal or non-existent, and its influence was deemed negligible.\u003c/p\u003e \u003c/div\u003e"},{"header":"3. Results","content":"\u003cp\u003e \u003cb\u003eCausal effects of cholecystitis on hepatic bile duct cancer\u003c/b\u003e \u003c/p\u003e \u003cp\u003eIn the two-way Mendelian randomization analysis, 62 SNPs were extracted with cholecystitis as the exposure and cholangiocarcinoma as the outcome. The IVW analysis showed an increased risk of cholangiocarcinoma in cholecystitis patients (OR\u0026thinsp;=\u0026thinsp;1.270, 95% CI\u0026thinsp;=\u0026thinsp;1.038\u0026ndash;1.553, P\u0026thinsp;=\u0026thinsp;0.020). However, MR Egger, weighted median method, simple mode, and weighted mode provided more conservative suggesting that there may not be a significant association between the presence of cholecystitis and an increased risk of cholangiocarcinoma (MR Egger: OR\u0026thinsp;=\u0026thinsp;1.282, 95% CI\u0026thinsp;=\u0026thinsp;0.755\u0026ndash;2.177, P\u0026thinsp;=\u0026thinsp;0.361; weighted median: OR\u0026thinsp;=\u0026thinsp;1.155, 95% CI\u0026thinsp;=\u0026thinsp;0.915\u0026ndash;1.460, P\u0026thinsp;=\u0026thinsp;0.226; simple mode: OR\u0026thinsp;=\u0026thinsp;1.362, 95% CI\u0026thinsp;=\u0026thinsp;0.815\u0026ndash;2.274, P\u0026thinsp;=\u0026thinsp;0.243; weighted mode: OR\u0026thinsp;=\u0026thinsp;1.110, 95% CI: 0.783\u0026ndash;1.574, P\u0026thinsp;=\u0026thinsp;0.561) (Table\u0026nbsp;1 and Fig.\u0026nbsp;2).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePresents the MR estimates for assessing the causal effect of cholecystitis on the risk of cholangiocarcinoma\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMR method\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNumber of SNPs\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eBeat\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eSE\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eAssociation p-value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eOdds ratio\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e95% confidence interval\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIVW\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.239\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.103\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.020\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.270\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e1.038\u0026ndash;1.553\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMR Egger\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.248\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.270\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.361\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.282\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.755\u0026ndash;2.177\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWeighted median\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.144\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.119\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.226\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.155\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.915\u0026ndash;1.460\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSimple mode\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.309\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.262\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.243\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.362\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.815\u0026ndash;2.274\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWeighted mode\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.104\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.178\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.561\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.110\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.783\u0026ndash;1.574\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eMR, Mendelian randomization; IVW, Inverse Variance Weighted; SNP, Single nucleotide polymorphism; SE, Standard error.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eScatter plots of SNP effect sizes for cholecystitis and cholangiocarcinoma are shown in Fig.\u0026nbsp;3. The study findings indicate that the estimated causal effects of cholangiocarcinoma were highly consistent across IVW, MR Egger, weighted median, simple mode, and weighted modes for cholecystitis. Cholelithiasis is a risk factor for cholangiocarcinoma, although the significance varied among different studies.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIn this study, we extracted 62 cholecystitis-related SNPs as instrumental variables (R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001, P\u0026thinsp;\u0026lt;\u0026thinsp;5\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;6\u003c/sup\u003e) from the GWAS study. The impact of each SNP locus on cholangiocarcinoma. Furthermore, we also conducted leave-one-SNP-out analyses to identify the effect of each SNP on the overall causal estimates. No significant differences in the estimated causal effects were observed when we removed individual SNPs from our MR analysis one by one. Consequently, the estimated effect cannot be explained by any single SNP (Fig.\u0026nbsp;4).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFunnel plots revealed that the Wald ratio of each SNP plotted was inversely related to their accuracy. The approximate symmetry indicated that the gene does not exhibit significant heterogeneity, and there is no systematic deviation between the research effect and its accuracy. Our results show that cholelithiasis is a risk factor for cholangiocarcinoma without significant heterogeneity (Fig.\u0026nbsp;5).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"4. Discussion","content":"\u003cp\u003eThis study represents the pioneering effort to systematically evaluate the causal link between genetic susceptibility to cholecystitis and the incidence of cholangiocarcinoma. Our findings elucidate that genetically predicted cholecystitis correlates with heightened risk of cholangiocarcinoma. This positive association between the two conditions was robustly affirmed through sensitivity analyses. Overall, our Mendelian randomization investigation underscores a causal, unidirectional relationship between cholecystitis and the susceptibility to cholangiocarcinoma, indicating an elevated risk of cholangiocarcinoma among individuals with cholecystitis.\u003c/p\u003e \u003cp\u003ePrevious research has elucidated the intricate interplay between chronic inflammation of the intrahepatic bile duct and the pathogenesis of cholangiocarcinoma. This chronic inflammatory milieu triggers abnormal hyperplasia of the bile duct endothelium and glandular mucosal epithelium. Additionally, factors such as altered bile composition, cholestasis, and metabolic conditions contribute to the progressive damage of the bile duct endothelium and mucosal epithelium, including glandular structures. This cascade of events culminates in a spectrum of changes ranging from hyperplasia and metaplasia to atypical hyperplasia, eventually progressing to cancerous transformation\u003csup\u003e\u003cspan additionalcitationids=\"CR32\" citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e\u003c/sup\u003e. Cholecystitis, a common inflammatory condition affecting the gallbladder, has been identified as a significant risk factor for the development of cholangiocarcinoma. A population-based case-control study conducted by Chang et al. highlighted various factors associated with an elevated risk of cholangiocarcinoma, including cholangitis, cholelithiasis, cholecystitis, cirrhosis of the liver, alcoholic liver disease, chronic non-alcoholic liver disease, diabetes, chronic pancreatitis, inflammatory bowel disease, and peptic ulcer\u003csup\u003e\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e. Furthermore, a systematic review and meta-analysis underscored a substantially heightened risk of cholangiocarcinoma in patients with cholangitis (OR: 6.3, 95% CI: 2.3\u0026ndash;17.5)\u003csup\u003e\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e\u003c/sup\u003e. In line with these observational findings, our study unveils a novel insight into the genetic underpinnings of cholecystitis and its causal relationship with cholangiocarcinoma. Utilizing rigorous Mendelian randomization methods including the IVW method, MR Egger regression, and the weighted median method, we observed a 27.00% increased risk of cholangiocarcinoma associated with genetic predisposition to cholecystitis. These robust findings further support the notion that cholecystitis may indeed heighten the risk of cholangiocarcinoma, as indicated by collective evidence from observational studies.\u003c/p\u003e \u003cp\u003eTo reveal the intricate relationship between cholecystitis and cholangiocarcinoma development, it is essential to first consider a wide array of preventive measures, diagnostic techniques, and therapeutic strategies tailored for managing cholecystitis. Our primary investigation, meticulously incorporating genetic testing at a stringent significance threshold of P\u0026thinsp;\u0026lt;\u0026thinsp;5\u0026times;10\u003csup\u003e\u0026minus;\u0026thinsp;8\u003c/sup\u003e, has provided compelling evidence bolstering the hypothesis that heightened genetic susceptibility to cholecystitis correlates with an elevated risk of cholangiocarcinoma. This pivotal finding underscores the potential role of genetic factors in predisposing individuals to both conditions, offering valuable insights into the underlying molecular mechanisms and potential avenues for targeted intervention and precision medicine approaches.\u003c/p\u003e \u003cp\u003eThe MR method offers a robust approach for assessing causality by establishing a link between an \"exposure\" and an \"outcome,\" thereby mitigating the risk of confounding inherent in traditional observational studies. While observational studies are frequently relied upon to infer causality, they can be time-consuming and impractical. It is noteworthy that gallstones are implicated in 80\u0026ndash;95% of acute cholecystitis cases, with acalculous cholecystitis comprising the remaining 5\u0026ndash;10% of cases\u003csup\u003e\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e,\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e\u003c/sup\u003e. However, many studies predominantly focus on the impact of gallstones, overlooking the significant contribution of cholecystitis itself. In our study, we conducted a two-sample MR analysis, which revealed a causal relationship from cholecystitis to cholangiocarcinoma. Our findings underscore the critical importance of initiating treatment promptly following cholecystitis diagnosis to optimize clinical outcomes and mitigate potential complications, such as cholangiocarcinoma. Furthermore, we advocate for early screening for cholangiocarcinoma risk among cholecystitis patients, as this proactive approach may facilitate earlier diagnosis and timely initiation of curative interventions for cholangiocarcinoma. Overall, our systematic meta-analysis, conducted in a large population of European ancestry, sheds light on the relationship between cholecystitis and cholangiocarcinoma, offering valuable insights for informing preventive care strategies for cholangiocarcinoma and identifying pivotal intervention points for managing cholangiocarcinoma in patients with cholecystitis.\u003c/p\u003e \u003cp\u003eOur study delved into the causal association between cholangiocarcinoma and cholecystitis, guided by earlier research highlighting chronic inflammation as the primary driver of progression from cholecystitis to cholangiocarcinoma. This chronic inflammatory milieu can trigger a cascade of events, including epigenetic alterations, activation of proto-oncogenes, and deactivation of tumor suppressor genes, culminating in abnormal cell proliferation, differentiation, and an elevated cancer risk. For instance, an inflammatory microenvironment characterized by elevated levels of pro-inflammatory cytokines, growth factors, and toxic bile acids may foster accelerated mitosis of normal bile duct cells, predisposing them to mutations and uncontrolled proliferation. Epigenetic modifications in intrahepatic cholangiocarcinoma epithelial cells can be induced by pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and transforming growth factor-β (TGF-β), akin to tumor suppressor inactivation and oncogene activation mechanisms\u003csup\u003e\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e,\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e\u003c/sup\u003e. Of particular interest, IL-6, upon binding to the gp130 receptor, triggers JAK1/2 activation, leading to subsequent STAT3 phosphorylation and activation. This signaling cascade may also activate extracellular signal-regulated kinase 1/2 (ERK1/2) and p38/MAPK pathways, ultimately fueling tumor proliferation and cholangiocarcinoma progression\u003csup\u003e\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e\u003c/sup\u003e. Future studies should endeavor to explore additional potential mechanistic pathways to inform the development of pertinent clinical recommendations in the management of cholecystitis-associated cholangiocarcinoma.\u003c/p\u003e \u003cp\u003eIt's important to recognize limitations in our study. The biological mechanisms of cholecystitis and cholangiocarcinoma are complex, involving many factors. Using certain genetic markers with unclear roles in Mendelian randomization may challenge our assumptions. Also, genetic differences can vary among ethnic groups. While our study focused on one population, more research on diverse populations is needed for stronger evidence. Additionally, we should conduct formal mediation analysis to understand how cholecystitis might lead to cholangiocarcinoma. Cholangiocarcinoma patients show diverse characteristics, suggesting cholecystitis could be linked to specific subtypes. Future studies should explore these subgroups further to better understand the relationships.\u003c/p\u003e \u003cp\u003eIn conclusion, this study strengthened the argument for a genetic connection between susceptibility to cholecystitis and cholangiocarcinoma. Considering the high mortality and poor prognosis associated with cholangiocarcinoma patients, it is important to identify and manage the risk factor of cholecystitis for cholangiocarcinoma to reduce its morbidity.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eIEU\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eIntegrative Epidemiology Unit\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMR\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMendelian randomization\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eGWAS\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eGenome-wide association studies\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eSEs\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eStandard errors\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eSNP\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eSingle nucleotide polymorphism\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eIVW\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eInverse variance weighted\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eTNF-α\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eTumor necrosis factor-α\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eIL-6\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eInterleukin-6\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eTGF-β\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eTransforming growth factor-β\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eERK1/2\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eExtracellular signal-regulated kinase 1/2.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePublicly available datasets were analyzed in this study. Our study utilized pooled GWAS data from the IEU, publicly accessible at https://gwas.mrcieu.ac.uk/.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research was funded by Cuiying Scientific and Technological Innovation Program of Lanzhou University Second Hospital-CY2022-MS-A18, Major Science and Technology Project of Gansu Province [20ZD7FA003, 22ZD6FA050, 22JR9KA002] and Natural Science Foundation of Gansu Province (21JR1RA135, 23JRRA1001).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eXG: Writing\u0026mdash;original draft preparation, investigation, and figure preparation. HG: Investigation, figure preparation and analyzed the data. SW: Investigation. FT: Investigation. YZ: Investigation. YL: Conceptualization, methodology, and supervision. All authors contributed to the article and approved the submitted version.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eKhan AS, Dageforde LA, Cholangiocarcinoma. Surg Clin North Am Apr. 2019;99(2):315\u0026ndash;35. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.suc.2018.12.004\u003c/span\u003e\u003cspan address=\"10.1016/j.suc.2018.12.004\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGatto M, Bragazzi MC, Semeraro R, et al. Cholangiocarcinoma: update and future perspectives. 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Nat Rev Dis Primers Sep. 2021;9(1):65. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1038/s41572-021-00300-2\u003c/span\u003e\u003cspan address=\"10.1038/s41572-021-00300-2\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-gastroenterology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmge","sideBox":"Learn more about [BMC Gastroenterology](http://bmcgastroenterol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bmge/default.aspx","title":"BMC Gastroenterology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Cholecystitis, cholangiocarcinoma, mendelian randomization analysis","lastPublishedDoi":"10.21203/rs.3.rs-4470063/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4470063/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn recent years, the incidence of cholangiocarcinoma increases. Epidemiological studies suggest that cholecystitis elevates the risk of hepatobiliary cancer. However, an independent causal relationship remains unrevealed. Observational studies are vulnerable to residual confounders and bias, which compromises causal inference. Our study aimed to evaluate whether cholecystitis is an independent risk factor for cholangiocarcinoma.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eInstrument variables were identified as independent single nucleotide polymorphisms highly associated with cholecystitis (n = 62). The entire dataset from the Integrative Epidemiology Unit (IEU) public availability genome-wide association studies was utilized to determine outcomes for cholangiocarcinoma (n = 62). In this study, five Mendelian randomization (MR) statistical techniques (Inverse Variance Weighted, MR Egger, Weighted Median, Simple Mode, and Weighted mode) were used. The MR Egger intercept test, leave-one-out analysis, and the funnel plot were all utilized in sensitivity analyses.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eResults of the Inverse Variance Weighted tests genetically predicted that cholecystitis was significantly associated with higher risk of cholangiocarcinoma, with an odds ratio of 1.27 (95% CI: 1.038–1.553; P = 0.02). But the Weighted Median Method, MR Egger Regression, Simple Mode, and Weighted Mode all showed no statistical significance (P \u0026gt; 0.05). Both funnel plots and MR Egger intercepts indicated the absence of any directional pleiotropic effects between cholecystitis and cholangiocarcinoma.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe found potential evidence of a causal effect between cholecystitis and cholangiocarcinoma, indicating an increased likelihood of cholangiocarcinoma in patients with cholecystitis through mendelian randomization analysis. Our results excepted enhance the management of patients with cholecystitis to decrease the risk of cholangiocarcinoma.\u003c/p\u003e","manuscriptTitle":"Cholecystitis and cholangiocarcinoma: a two-sample mendelian randomization study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-06-10 22:33:49","doi":"10.21203/rs.3.rs-4470063/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-05-28T12:54:16+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-05-24T15:31:42+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-05-24T15:31:42+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Gastroenterology","date":"2024-05-24T05:00:02+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-gastroenterology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmge","sideBox":"Learn more about [BMC Gastroenterology](http://bmcgastroenterol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bmge/default.aspx","title":"BMC Gastroenterology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"6c6ee64e-8364-4474-a8e3-b40e4d1906e2","owner":[],"postedDate":"June 10th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-09-01T16:04:26+00:00","versionOfRecord":{"articleIdentity":"rs-4470063","link":"https://doi.org/10.1186/s12876-025-04199-x","journal":{"identity":"bmc-gastroenterology","isVorOnly":false,"title":"BMC Gastroenterology"},"publishedOn":"2025-08-26 15:57:23","publishedOnDateReadable":"August 26th, 2025"},"versionCreatedAt":"2024-06-10 22:33:49","video":"","vorDoi":"10.1186/s12876-025-04199-x","vorDoiUrl":"https://doi.org/10.1186/s12876-025-04199-x","workflowStages":[]},"version":"v1","identity":"rs-4470063","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4470063","identity":"rs-4470063","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}