Carrying asymptomatic gallstones is not associated with changes in intestinal microbiota composition and diversity but cholecystectomy with significant dysbiosis

Association between Atherogenic index of plasma and gallstones in the United States adults: A cross-sectional analysis of NHANES 2017-2020

Background

Although substantial evidence suggests an association between dyslipidemia as an isolated factor and gallstones, research on the Atherogenic Index of Plasma (AIP) and gallstones remains limited.

Methods

A total of 3557 eligible adults from the United States were selected for cross-sectional analysis using the 2017-2020 National Health and Nutrition Examination Survey database. Logistic regression was employed to evaluate the association between AIP gallstones. Restricted cubic spline (RCS) analysis and threshold effect analysis were conducted to explore potential non-linear relationship.

Results

The study found a positive association between higher AIP levels and higher odds of gallstones. In the fully adjusted logistic regression model, each 1-unit increase in AIP was associated with 59 % higher odds of gallstones (OR = 1.59, 95 % CI: 1.06, 2.38). Compared to the lowest quartile of AIP, the highest quartile showed 82 % higher odds of gallstones (OR = 1.82, 95 % CI: 1.23, 2.69). RCS analysis revealed a non-linear relationship between AIP and gallstones, with threshold effect analysis identifying a turning point at -0.13, where AIP had a positive correlation with gallstones before this threshold.

Conclusion

Higher AIP is positively correlated with higher odds of gallstones, showing a non-linear relationship. As AIP increases, the odds of gallstones also rise, but this relationship is no longer observed beyond a certain threshold. It is recommended to maintain appropriate AIP levels to reduce the incidence of gallstones.

Postcholecystectomy Gut Microbiome Changes and the Clinical Impact: A Systematic Review With Narrative Synthesis

BACKGROUND

Cholecystectomy (CCE) can affect the enterohepatic circulation of bile acids and result in gut microbiome changes. This systematic review aimed to clarify the effect of CCE on gut microbiome composition and its clinical impact.

METHOD

A systematic search was conducted in PubMed, Web of Science, and Scopus, combining keywords such as "cholecystectomy" or "post-cholecystectomy" with "gut microbiome," "stool microbiome," or "gut dysbiosis." Data were extracted and synthesized using narrative review. Study quality was assessed using the Newcastle-Ottawa scale.

RESULTS

A total of 1373 articles were screened and 14 studies were selected. Significant but inconsistent microbiome changes were reported. Changes were observed in alpha and beta diversity. At phylum level, an increase in Bacteroides and Ascomycota, decrease in Firmicutes, Actinomycetes, and Basidiomycota, and both increase and decrease in Fusobacteria were reported. At genus level, an increase in Prevotella and a decrease in Faecalibacterium were reported. In post-CCE diarrhea, decreased beta diversity, a decreased F/B ratio, an increase in Prevotella, an increase in Phocaeicola vulgatus, and a decrease in Prevotella copri were noted. For post-CCE syndrome, a higher abundance of Proteobacteria and decreased Firmicutes/Bacteroides (F/B) ratio were reported. A decreased relative abundance of Bifidobacterium longum subsp. longum from controls to CCE without colonic neoplasia to CCE with colonic neoplasia, and an increased abundance of Candida glabrata from controls, to CCE without colonic neoplasia and CCE with colonic neoplasia, were reported.

CONCLUSION

Patients who underwent CCE had significant gut dysbiosis. However, current studies could not clarify the detailed gut microbial structural and functional changes associated with CCE.

Fecal glycoprotein 2 is a marker of gut microbiota dysbiosis and systemic inflammation

BACKGROUND

Antimicrobial autoantigenic glycoprotein 2 (GP2) is an important component of the innate immune system which originates from the exocrine pancreas as well as from the small intestines. The relationship of GP2 with the intestinal microbiome as well as the systemic implications of increased fecal GP2 levels are, however, still unclear. Therefore, fecal samples from 2,812 individuals of the Study of Health in Pomerania (SHIP) were collected to determine GP2 levels (enzyme-linked immunosorbent assay) and gut microbiota profiles (16 S rRNA gene sequencing). These data were correlated and associated with highly standardised and comprehensive phenotypic data of the study participants.

RESULTS

Fecal GP2 levels were increased in individuals with higher body mass index and smokers, whereas lower levels were found in case of preserved exocrine pancreatic function, female sex or a healthier diet. Moreover, higher GP2 levels were associated with increased serum levels of high-sensitivity C-reactive protein, loss of gut microbial diversity and an increase of potentially detrimental bacteria (Streptococcus, Haemophilus, Clostridium XIVa, or Collinsella). At the same time, predicted microbial pathways for the biosynthesis of beneficial short-chain fatty acids or lactic acid were depleted in individuals with high fecal GP2. Of note, GP2 exhibited a stronger association to overall microbiome variation than calprotectin.

CONCLUSION

Fecal GP2 is a biomarker of gut microbiota dysbiosis and associated with increased systemic inflammation. The intestines may be more important as origin for GP2 than pancreatic acinar cells. Future studies need to investigate the potential clinical value in disease specific patient cohorts.

Sex disparities in gallstone disease: insights from the MAUCO prospective population-based cohort study

OBJECTIVE

To investigate factors associated with the prevalence and incidence of gallstone disease (GSD) in women and men of the MAUCO population-based prospective cohort.

DESIGN

8948 MAUCO participants (aged 38-74 years) underwent abdominal ultrasound at baseline (2015-2019); 4385 received follow-up ultrasound at years 2 or 4. Factors associated with prevalent GSD were assessed using Poisson multiple regression and with incident GSD using Cox regression models.

RESULTS

GSD prevalence was 40.4% in women (13.1% gallstones, 27.3% cholecystectomies) and 17.1% in men (8.9% gallstones, 8.2% cholecystectomies). In men, GSD prevalence rate ratio (PRR) by age in >64 years was 3.85 (95% CI 3.00 to 4.94), doubling that of women's PRR 1.78 (95% CI 1.57 to 2.01). In women, waist circumference and diabetes were stronger GSD factors; a higher number of children and worse metabolic and socioeconomic conditions were also highlighted. GSD men had higher cardiovascular disease and a family history of GSD and gallbladder cancer. 198 GSD cases developed during follow-up, with incidence increasing by 2% (95% CI 1.005% to 1.03%) per each centimetre above the ideal waist circumference, statistically significant only in women. In men, age was the strongest factor for incidence, followed by a family history of GSD and low high-density lipoprotein increased incidence risk.

CONCLUSIONS

GSD burden was high in this population; a third of women had their gallbladder removed, which may pose them at risk of other health problems. Abdominal obesity was the only preventable GSD risk factor, highlighting the need for effective public health policies promoting obesity reduction.

Alteration of ascending colon mucosal microbiota in patients after cholecystectomy

BACKGROUND

Cholecystectomy is a successful treatment option for gallstones, although the incidence of colorectal cancer (CRC) has notably increased in post-cholecystectomy (PC) patients. However, it remains uncertain whether the altered mucosal microbiota in the ascending colon is related.

AIM

To investigate the potential correlation between gut microbiota and the surgical procedure of cholecystectomy.

METHODS

In total, 30 PC patients and 28 healthy controls underwent colonoscopies to collect mucosal biopsy samples. PC patients were divided based on their clinical features. Then, 16S-rRNA gene sequencing was used to analyze the amplicon, alpha diversity, beta diversity, and composition of the bacterial communities. Additionally, the Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) database, sourced from the Kyoto Encyclopedia of Genes and Genomes, was used to predict the functional capabilities of the bacteria.

RESULTS

PC patients were comparable with healthy controls. However, PC patients older than 60 years had a distinct composition compared to those under 60 years old. Bacteroidetes richness was considerably higher at the phylum level in PC patients. Bacteroides, Parabacteroides, and Bilophila were more abundant in the PC group than in the control group. Furthermore, PC patients exhibited greater enrichment in metabolic pathways, specifically those related to lipopolysaccharide biosynthesis and vancomycin group antibiotic production, than controls.

CONCLUSION

This study indicated that the mucosal microbiota in PC patients was altered, perhaps offering new perspectives on the treatment possibilities for CRC and diarrhea following cholecystectomy.

The alteration of fecal microbial and metabolic profile of gallstone patients in Taiwan: Single-center study

BACKGROUND

Gallstone disease is a common health problem worldwide. The role of the gut microbiota in gallstone pathogenesis remains obscure. Our aim was to evaluate the association and crosstalk between gut microbiota, gut metabolomic, and metabolic parameters in cholesterol gallstone patients, pigmented gallstone patients, and controls.

METHODS

We collected stool samples from healthy individuals and patients with gallstones in our hospital from March 2019 to February 2021. 16s rRNA sequencing was performed, followed by differential abundance analyses. Measurement of bile acids and short-chain fatty acids was conducted via targeted metabolomics.

RESULT

Thirty healthy individuals and 20 gallstone patients were recruited. The intergroup difference of microbial composition was significant between control and gallstone patients. The control group had more abundant Faecalibacterium , Prevotella 9 , and Bacteroides plebeius DSM 17135 . The cholesterol stones group had higher Desulfovibrionaceae and Bacteroides uniformis than the other two groups, while the pigment stone group had more abundant Escherichia-Shigella . In the analysis of metabolites, only n-butyric acid had a significantly higher concentration in the controls than in the gallstone group ( p < 0.01). The level of 3α-hydroxy-12 ketolithocholic acid, deoxycholic acid, and cholic acid showed no intergroup differences but was correlated to the serum cholesterol level and bacterial richness and evenness.

CONCLUSION

Our study revealed the key taxa that can discriminate between individuals with or without gallstones. We also identified metabolites that are possibly associated with metabolic parameter and bacterial diversity. However, the correlation of the metabolites to certain clusters of bacteria should be analyzed in a larger cohort.

Microbiota-gut-brain axis and its therapeutic applications in neurodegenerative diseases

The human gastrointestinal tract is populated with a diverse microbial community. The vast genetic and metabolic potential of the gut microbiome underpins its ubiquity in nearly every aspect of human biology, including health maintenance, development, aging, and disease. The advent of new sequencing technologies and culture-independent methods has allowed researchers to move beyond correlative studies toward mechanistic explorations to shed light on microbiome-host interactions. Evidence has unveiled the bidirectional communication between the gut microbiome and the central nervous system, referred to as the "microbiota-gut-brain axis". The microbiota-gut-brain axis represents an important regulator of glial functions, making it an actionable target to ameliorate the development and progression of neurodegenerative diseases. In this review, we discuss the mechanisms of the microbiota-gut-brain axis in neurodegenerative diseases. As the gut microbiome provides essential cues to microglia, astrocytes, and oligodendrocytes, we examine the communications between gut microbiota and these glial cells during healthy states and neurodegenerative diseases. Subsequently, we discuss the mechanisms of the microbiota-gut-brain axis in neurodegenerative diseases using a metabolite-centric approach, while also examining the role of gut microbiota-related neurotransmitters and gut hormones. Next, we examine the potential of targeting the intestinal barrier, blood-brain barrier, meninges, and peripheral immune system to counteract glial dysfunction in neurodegeneration. Finally, we conclude by assessing the pre-clinical and clinical evidence of probiotics, prebiotics, and fecal microbiota transplantation in neurodegenerative diseases. A thorough comprehension of the microbiota-gut-brain axis will foster the development of effective therapeutic interventions for the management of neurodegenerative diseases.

Inflammation-associated ectopic mineralization

Ectopic mineralization refers to the deposition of mineralized complexes in the extracellular matrix of soft tissues. Calcific aortic valve disease, vascular calcification, gallstones, kidney stones, and abnormal mineralization in arthritis are common examples of ectopic mineralization. They are debilitating diseases and exhibit excess mortality, disability, and morbidity, which impose on patients with limited social or financial resources. Recent recognition that inflammation plays an important role in ectopic mineralization has attracted the attention of scientists from different research fields. In the present review, we summarize the origin of inflammation in ectopic mineralization and different channels whereby inflammation drives the initiation and progression of ectopic mineralization. The current knowledge of inflammatory milieu in pathological mineralization is reviewed, including how immune cells, pro-inflammatory mediators, and osteogenic signaling pathways induce the osteogenic transition of connective tissue cells, providing nucleating sites and assembly of aberrant minerals. Advances in the understanding of the underlying mechanisms involved in inflammatory-mediated ectopic mineralization enable novel strategies to be developed that may lead to the resolution of these enervating conditions.

Cholecystectomy Significantly Alters Gut Microbiota Homeostasis and Metabolic Profiles: A Cross-Sectional Study

Cholecystectomy (CCE) is a standard clinical treatment for conditions like gallstones and cholecystitis. However, its link to post-CCE syndrome, colorectal cancer, and nonalcoholic fatty liver disease has raised concerns. Additionally, studies have demonstrated the disruptive effects of CCE on gut microbiota homeostasis and bile acid (BA) metabolism. Considering the role of gut microbiota in regulating host metabolic and immune pathways, the use of dietary and probiotic intervention strategies to maintain a stable gut ecosystem after CCE could potentially reduce associated disease risks. Inter-study variations have made it challenging to identify consistent gut microbiota patterns after CCE, a prerequisite for targeted interventions. In this study, we first meta-analyzed 218 raw 16S rRNA gene sequencing datasets to determine consistent patterns of structural and functional changes in the gut microbiota after CCE. Our results revealed significant alterations in the gut microbiota's structure and function due to CCE. Furthermore, we identified characteristic gut microbiota changes associated with CCE by constructing a random model classifier. In the validation cohort, this classifier achieved an area under the receiver operating characteristic curve (AUC) of 0.713 and 0.683 when distinguishing between the microbiota of the CCE and healthy groups at the family and genus levels, respectively. Further, fecal metabolomics analysis demonstrated that CCE also substantially modified the metabolic profile, including decreased fecal short-chain fatty acid levels and disrupted BA metabolism. Importantly, dietary patterns, particularly excessive fat and total energy intake, influenced gut microbiota and metabolic profile changes post-CCE. These dietary habits were associated with further enrichment of the microbiota related to BA metabolism and increased levels of intestinal inflammation after CCE. In conclusion, our study identified specific alterations in gut microbiota homeostasis and metabolic profiles associated with CCE. It also revealed a potential link between dietary patterns and gut microbiota changes following CCE. Our study provides a theoretical basis for modulating gut microbiota homeostasis after CCE using long-term dietary strategies and probiotic interventions.

The necessity and safety of simultaneous cholecystectomy during gastric surgery for patients with asymptomatic cholelithiasis

OBJECTIVES

The incidence of cholelithiasis is higher among individuals who have undergone gastric surgery. The benefits of concomitant gallbladder removal in asymptomatic gallstone patients remain uncertain. The aim was to investigate the necessity and safety of simultaneous cholecystectomy in this particular patient population.

METHODS

We performed a systematic review and meta-analysis to assess the incidence of asymptomatic cholelithiasis converting to symptomatic after gastric surgery and the complication rate associated with simultaneous cholecystectomy. PubMed, Embase, and the Cochrane Library were searched for relevant articles published until 10 March 202210 March 2022.

RESULTS

Patients with asymptomatic cholelithiasis after gastric surgery were at a higher risk of developing symptomatic cholelithiasis compared to those without cholelithiasis (relative risk [RR] 2.28, 95% confidence interval [CI] 1.23-4.25) and those with unknown gallbladder conditions (RR 2.70, 95% CI 1.54-4.73). Additionally, patients who underwent simultaneous cholecystectomy did not face a higher risk of complications compared to those who only underwent gastric surgery (RR 0.86, 95% CI 0.48-1.53).

CONCLUSIONS

Simultaneous cholecystectomy is both necessary and safe for patients with asymptomatic cholelithiasis undergoing gastric surgery. It is crucial to assess the gallbladder's condition before gastric surgery, and if the gallbladder status is unknown, simultaneous cholecystectomy should be avoided.

Gastrointestinal microbiome and cholelithiasis: Current status and perspectives

Cholelithiasis is a common digestive disease affecting 10% to 15% of adults. It imposes significant global health and financial burdens. However, the pathogenesis of cholelithiasis involves several factors and is incompletely elucidated. In addition to genetic predisposition and hepatic hypersecretion, the pathogenesis of cholelithiasis might involve the gastrointestinal (GI) microbiome, consisting of microorganisms and their metabolites. High-throughput sequencing studies have elucidated the role of bile, gallstones, and the fecal microbiome in cholelithiasis, associating microbiota dysbiosis with gallstone formation. The GI microbiome may drive cholelithogenesis by regulating bile acid metabolism and related signaling pathways. This review examines the literature implicating the GI microbiome in cholelithiasis, specifically gallbladder stones, choledocholithiasis, and asymptomatic gallstones. We also discuss alterations of the GI microbiome and its influence on cholelithogenesis.

Gastrointestinal microbiome and cholelithiasis: Current status and perspectives

Cholelithiasis is a common digestive disease affecting 10% to 15% of adults. It imposes significant global health and financial burdens. However, the pathogenesis of cholelithiasis involves several factors and is incompletely elucidated. In addition to genetic predisposition and hepatic hypersecretion, the pathogenesis of cholelithiasis might involve the gastrointestinal (GI) microbiome, consisting of microorganisms and their metabolites. High-throughput sequencing studies have elucidated the role of bile, gallstones, and the fecal microbiome in cholelithiasis, associating microbiota dysbiosis with gallstone formation. The GI microbiome may drive cholelithogenesis by regulating bile acid metabolism and related signaling pathways. This review examines the literature implicating the GI microbiome in cholelithiasis, specifically gallbladder stones, choledocholithiasis, and asymptomatic gallstones. We also discuss alterations of the GI microbiome and its influence on cholelithogenesis.

Adipose Tissue, Bile Acids, and Gut Microbiome Species Associated With Gallstones After Bariatric Surgery

Several risk factors are associated with gallstone disease after bariatric surgery, but the underlying pathophysiological mechanisms of gallstone formation are unclear. We hypothesize that gallstone formation after bariatric surgery is induced by different pathways compared with gallstone formation in the general population, since postoperative formation occurs rapidly in patients who did not develop gallstones in preceding years. To identify both pathophysiological and potentially protective mechanisms against postoperative gallstone formation, we compared the preoperative fasting metabolome, fecal microbiome, and liver and adipose tissue transcriptome obtained before or during bariatric surgery of obese patients with and without postoperative gallstones. In total, 88 patients were selected from the BARIA longitudinal cohort study. Within this group, 32 patients had postoperative gallstones within 2 years. Gut microbiota metagenomic analyses showed group differences in abundance of 41 bacterial species, particularly abundance of Lactobacillaceae and Enterobacteriaceae in patients without gallstones. Subcutaneous adipose tissue transcriptomic analyses revealed four genes that were suppressed in gallstone patients compared with patients without gallstones. These baseline gene expression and gut microbiota composition differences might relate to protective mechanisms against gallstone formation after bariatric surgery. Moreover, baseline fasting blood samples of patients with postoperative gallstones showed increased levels of several bile acids. Overall, we revealed different genes and bacteria associated with gallstones than those previously reported in the general population, supporting the hypothesis that gallstone formation after bariatric surgery follows a different trajectory. Further research is necessary to confirm the involvement of the bile acids, adipose tissue activity, and microbial species observed here.

Cholecystectomy for asymptomatic gallstones: Markov decision tree analysis

Gallstones are a common public health problem, especially in developed countries. There are an increasing number of patients who are diagnosed with gallstones due to increasing awareness and liberal use of imaging, with 22.6%-80% of gallstone patients being asymptomatic at the time of diagnosis. Despite being asymptomatic, this group of patients are still at life-long risk of developing symptoms and complications such as acute cholangitis and acute biliary pancreatitis. Hence, while early prophylactic cholecystectomy may have some benefits in selected groups of patients, the current standard practice is to recommend cholecystectomy only after symptoms or complications occur. After reviewing the current evidence about the natural course of asymptomatic gallstones, complications of cholecystectomy, quality of life outcomes, and economic outcomes, we recommend that the option of cholecystectomy should be discussed with all asymptomatic gallstone patients. Disclosure of material information is essential for patients to make an informed choice for prophylactic cholecystectomy. It is for the patient to decide on watchful waiting or prophylactic cholecystectomy, and not for the medical community to make a blanket policy of watchful waiting for asymptomatic gallstone patients. For patients with high-risk profiles, it is clinically justifiable to advocate cholecystectomy to minimize the likelihood of morbidity due to complications.

[Introduction to the microbiome]

The human body is colonized by a multitude of different microbes that are collectively referred to as the human microbiome. Gut microbes account for the largest proportion of these. They constitute a barrier against foreign pathogens, carry out important metabolic functions and regulate the immune system, thereby making them essential for the maintenance of health. The most important determinants of the gut microbiome structure in the general population include exocrine pancreatic function, genetics, nutrition, age, sex, and obesity. Changes in the gut microbiome have also been linked to a variety of diseases not limited to gastrointestinal disorders. Typical microbiome changes in disease include a loss of diversity and beneficial bacteria or an increase in opportunistic pathogens. This may result in a proinflammatory and unstable microbiome. Knowledge about the microbiome is rapidly increasing and microbiome modulation therapies have already been implemented in clinical practice. Therefore, basic knowledge about the microbiome is essential for all medical professionals in order for them to advise and treat their patients properly.

Cholecystectomy promotes the development of colorectal cancer by the alternation of bile acid metabolism and the gut microbiota

The incidence and mortality of colorectal cancer (CRC) have been markedly increasing worldwide, causing a tremendous burden to the healthcare system. Therefore, it is crucial to investigate the risk factors and pathogenesis of CRC. Cholecystectomy is a gold standard procedure for treating symptomatic cholelithiasis and gallstone diseases. The rhythm of bile acids entering the intestine is altered after cholecystectomy, which leads to metabolic disorders. Nonetheless, emerging evidence suggests that cholecystectomy might be associated with the development of CRC. It has been reported that alterations in bile acid metabolism and gut microbiota are the two main reasons. However, the potential mechanisms still need to be elucidated. In this review, we mainly discussed how bile acid metabolism, gut microbiota, and the interaction between the two factors influence the development of CRC. Subsequently, we summarized the underlying mechanisms of the alterations in bile acid metabolism after cholecystectomy including cellular level, molecular level, and signaling pathways. The potential mechanisms of the alterations on gut microbiota contain an imbalance of bile acid metabolism, cellular immune abnormality, acid-base imbalance, activation of cancer-related pathways, and induction of toxin, inflammation, and oxidative stress.

Cholecystectomy-induced secondary bile acids accumulation ameliorates colitis through inhibiting monocyte/macrophage recruitment

Although post-cholecystectomy (PC) patients usually have gastrointestinal complications and a higher risk of colorectal cancer, previous studies undetected a heightened risk of inflammatory bowel disease. Thus, we tried to investigate cholecystectomy's impact and pathophysiological mechanism on murine colitis models and clarify the association among fecal bile acids (BAs), mucosal bacterial microbiota, and immune cells in the PC patients. One month or three months after cholecystectomy, mice have induced colitis and tested BAs and fecal microbiota analysis. Next, mice were treated with various cholecystectomy-accumulated bile acids in drinking water for three months before inducing colitis. All 14 paired PC patients and healthy subjects were enrolled for BAs and mucosal microbiota analysis. Cholecystectomy ameliorated DSS-induced murine colitis, accelerated mucosal repair, and induced a significant shifting of fecal microbiota and BAs profiles under colitis status, which featured a higher relative abundance of species involved in BAs metabolism and increased secondary BAs concentrations. Cholecystectomy-associated secondary BAs (LCA, DCA, and HDCA) also ameliorated DSS-induced colitis and accelerated mucosal repair in mice. Cholecystectomy and specific secondary BAs treatments inhibited monocytes/macrophages recruitment in colitis mice. In vitro, cholecystectomy-associated secondary BAs also downregulated monocytes chemokines in the THP-1 derived macrophages through activation of the LXRα-linked signaling pathway. The alterations of mucosal microbiota and fecal BAs profiles were found in the PC patients, characterized as increased species with potential immuno-modulating effects and secondary BAs, which were negatively associated with peripheral monocytes levels. Cholecystectomy-induced secondary bile acids accumulation ameliorated colitis through inhibiting monocyte/macrophage recruitment, which might be mediated by the LXRα-related signaling pathway. Cholecystectomy, after 3 months follow-up, has an immune-regulatory role in murine colitis, preliminarily explaining that no increased risk of IBD had been reported in the PC patients, which still warrants further studies.

Increased Risk of Cancer after Cholecystectomy: A Nationwide Cohort Study in Korea including 123,295 Patients

Background/Aims

Contradictory findings on the association between cholecystectomy and cancer have been reported. We aimed to investigate the risk of all types of cancers or site-specific cancers in patients who underwent cholecystectomy using a nationwide dataset.

Methods

Subjects who underwent cholecystectomy from January 1, 2007, to December 31, 2014, who were older than 20 years and who underwent an initial baseline health check-up within 2 years were enrolled. Those who were diagnosed with any type of cancer before the enrollment or within 1 year after enrollment were excluded. Ultimately, patients (n=123,295) who underwent cholecystectomy and age/sex matched population (n=123,295) were identified from the database of the Korean National Health Insurance Service. The hazard ratio (HR) and 95% confidence interval (CI) for cancer were estimated, and Cox regression analysis was performed.

Results

The incidence of cancer in the cholecystectomy group was 9.56 per 1,000 personyears and that in the control group was 7.95 per 1,000 person-years. Patients who underwent cholecystectomy showed an increased risk of total cancer (adjusted HR, 1.19; 95% CI, 1.15 to 1.24; p<0.001), particularly leukemia and malignancies of the colon, liver, pancreas, biliary tract, thyroid, pharynx, and oral cavity. In the subgroup analysis according to sex, the risk of developing cancers in the pancreas, biliary tract, thyroid, lungs and stomach was higher in men than in women.

Conclusions

Physicians should pay more attention to the possibility of the occurrence of secondary cancers among patients who undergo cholecystectomy.

NMR Metabolomics Reveal Urine Markers of Microbiome Diversity and Identify Benzoate Metabolism as a Mediator between High Microbial Alpha Diversity and Metabolic Health

Microbial metabolites measured using NMR may serve as markers for physiological or pathological host–microbe interactions and possibly mediate the beneficial effects of microbiome diversity. Yet, comprehensive analyses of gut microbiome data and the urine NMR metabolome from large general population cohorts are missing. Here, we report the associations between gut microbiota abundances or metrics of alpha diversity, quantified from stool samples using 16S rRNA gene sequencing, with targeted urine NMR metabolites measures from 951 participants of the Study of Health in Pomerania (SHIP). We detected significant genus–metabolite associations for hippurate, succinate, indoxyl sulfate, and formate. Moreover, while replicating the previously reported association between hippurate and measures of alpha diversity, we identified formate and 4-hydroxyphenylacetate as novel markers of gut microbiome alpha diversity. Next, we predicted the urinary concentrations of each metabolite using genus abundances via an elastic net regression methodology. We found profound associations of the microbiome-based hippurate prediction score with markers of liver injury, inflammation, and metabolic health. Moreover, the microbiome-based prediction score for hippurate completely mediated the clinical association pattern of microbial diversity, hinting at a role of benzoate metabolism underlying the positive associations between high alpha diversity and healthy states. In conclusion, large-scale NMR urine metabolomics delivered novel insights into metabolic host–microbiome interactions, identifying pathways of benzoate metabolism as relevant candidates mediating the beneficial health effects of high microbial alpha diversity.

[The role of the microbiome in diseases of the pancreas]

BACKGROUND

The human body is inhabited by diverse microorganisms. Together, this so-called microbiome exerts important metabolic functions and contributes to the maintenance of health. At the same time, shifts in the microbiome composition may lead to disease.

OBJECTIVES

Review of the current literature about the role of the microbiome in diseases of the pancreas.

MATERIALS AND METHODS

Literature search in PubMed and Embase.

RESULTS

The exocrine pancreas is a major factor determining the composition and stability of the intestinal microbiome even in healthy people without pancreatic disease. Inflammatory diseases of the pancreas such as acute or chronic pancreatitis lead to reduced microbial diversity, loss of gut barrier stabilizing bacteria and an increase in facultative pathogens like Escherichia or Enterococcus. Even pancreatic cancer tissue harbours microbiota and mice models have shown that the growth of pancreatic cancer can be inhibited by microbiota ablation.

CONCLUSIONS

Inflammatory diseases of the pancreas lead to gut microbiome dysbiosis and tumor microbiota probably play a role in the development of pancreatic cancer. Until now, however, there is no proof that therapeutic microbiota modulation in individuals with pancreatic disease can improve mortality or quality of life. At this point, the analysis of the microbiome in pancreatic disease should only be performed in scientific studies.

Progress in the Study of Colorectal Cancer Caused by Altered Gut Microbiota After Cholecystectomy

Epidemiological studies have found an increased incidence of colorectal cancer (CRC) in people who undergo cholecystectomy compared to healthy individuals. After cholecystectomy, bile enters the duodenum directly, unregulated by the timing of meals. Disruption of the balance of bile acid metabolism and increased production of primary bile acids, which in turn affects the composition and abundance of intestinal microorganisms. The link among cholecystectomy, the gut microbiota, and the occurrence and development of CRC is becoming clearer. However, due to the complexity of the microbial community, the mechanistic connections are less well understood. In this review, we summarize the changes of gut microbiota after cholecystectomy and illuminate the potential mechanisms on CRC, such as inflammation and immune regulation, production of genotoxins, metabolism of dietary ingredients, activation of signaling pathways, and so on. By reviewing these, we aimed to unravel the interactions between the gut microbiota and its host and be better positioned to develop treatments for CRC after cholecystectomy.

Risk of aortic dissection or aneurysm in patients with gallstone disease: a retrospective cohort study in Taiwan

OBJECTIVE

This nationwide population-based cohort study was to compare the risk of aortic dissection (AD) or aortic aneurysm (AN) between the subjects with and without gallstone disease (GD). We also compare the risk of AD/AN between the patients with GD with and without cholecystectomy.

SETTING

This nationwide population-based cohort study.

PARTICIPANTS

We extracted the hospitalisation database from the National Health Insurance Research Database of Taiwan and identified a total of 343 300 patients aged ≥20 years with GD newly diagnosed between 2000 and 2010 as the study cohort, including 191 111 with cholecystectomy and 152 189 without cholecystectomy, respectively. We randomly selected those without GD as the control cohort, by 1:1 propensity score matching with the study cohort based on age, sex, comorbidities and year of the index date for GD diagnosis.

RESULTS

The incidence of AD/AN was 6.65/10 000 person-years for the GD cohort and 6.24/10 000 person-years for the non-GD cohort (adjusted HR (aHR)=1.11, 95% CI=1.09 to 1.13), respectively (p<0.001). Furthermore, the incidence of AD/AN in the patients with GD was 9.93/10 000 person-years for the non-cholecystectomy patients (aHR=1.24, 95% CI=1.22 to 1.26) and 4.63/10 000 person-years for the cholecystectomy patients (aHR=0.97, 95% CI=0.95 to 0.99), respectively (p<0.05).

CONCLUSIONS

The GD cohort was associated with and greater risk of AD/AN than the non-GD cohort, but the risk of AD/AN in the patients with GD would decrease after cholecystectomy.