Prevalence of gallbladder disease in American Indian populations: findings from the Strong Heart Study

Relationship between triglyceride-glucose index and gallstones risk: a population-based study

Background

Globally, gallstones represented a prevalent condition of the digestive system, heavily affected by metabolic dysfunctions such as obesity, dyslipidemia, insulin resistance, and diabetes. The triglyceride-glucose (TyG) index served as an accessible novel indicator for evaluating insulin resistance, offering a precise reflection of metabolic conditions. However, no studies have yet explored their relationship. The link between the TyG and gallstone risk was the primary purpose of this study.

Methods

Utilized data from the public database, the National Health and Nutrition Examination Survey, for the years 2017-2020. The logit model was utilized to elucidate the connection between the TyG and the gallstones risk. The restricted cubic spline (RCS) analysis served to verify any non-linear relationships existing between them. Sensitivity analyses, encompassing both stratified and interaction analyses, were conducted to identify populations of particular interest and assess potential interactions between covariates and the TyG index.

Results

A total of 4544 individuals were included. The risk of gallstones in high group was 1.6 times that of the low group. The potential cut-off value for the TyG index was 6.19. Above this threshold, there was a 40% heightened risk of gallstones with each one-unit increment in the TyG. The RCS analysis revealed the absence of a non-linear association between them. The populations warranting particular focus included those over 60 years, non-White people, individuals with a body mass index ≥25, smokers, drinkers, those with hypertension, and diabetes. Apart from smoking history, alcohol consumption, and history of diabetes, there were no interactions between other variables and the TyG index.

Conclusion

The current study represented the inaugural investigation into the link between TyG index and the risk of gallstones. A positive correlation existed between them, signifying that an increase in TyG paralleled an elevated risk of gallstones. No non-linear relationship has been found between them. Besides, a 40% increase in gallstone risk accompanied each unit rise in TyG. Considering the convenience and accessibility of TyG in clinical settings, it has a promising potential for clinical application.

Effects of Biliary Phospholipids on Cholesterol Crystallization and Growth in Gallstone Formation

The prevalence of cholesterol gallstone disease is increasing, primarily due to the global epidemic of obesity associated with insulin resistance, and this trend leads to a considerable healthcare, financial, and social burden worldwide. Although phospholipids play an essential role in maintaining cholesterol solubility in bile through both mixed micelles and vesicles, little attention has been paid to the impact of biliary phospholipids on the pathogenesis of cholesterol gallstone formation. A reduction or deficiency of biliary phospholipids results in a distinctly abnormal metastable physical-chemical state of bile predisposing to supersaturation with cholesterol. Changes in biliary phospholipid concentrations influence cholesterol crystallization by yielding both liquid crystalline and "anhydrous" crystalline metastable intermediates, evolving into classical parallelogram-shaped cholesterol monohydrate crystals in supersaturated bile. As a result, five distinct crystallization pathways, A-E, have been defined, mainly based on the prime habits of liquid and solid crystals in the physiological or pathophysiological cholesterol saturation of gallbladder and hepatic bile. This review concisely summarizes the chemical structures and physical-chemical properties of biliary phospholipids and their physiological functions in bile formation and cholesterol solubility in bile, as well as comprehensively discusses the latest advances in the role of biliary phospholipids in cholesterol crystallization and growth in gallstone formation, largely based on the findings from clinical and animal studies and in vitro experiments. The insights gleaned from uncovering the cholelithogenic mechanisms are expected to form a fundamental framework for investigating the hitherto elusive events in the earliest stage of cholesterol nucleation and crystallization. This may help to identify better measures for early diagnosis and prevention in susceptible subjects and effective treatment of patients with gallstones.

Causal associations between changes in lipid profiles and risk of gallstone disease: a two-sample Mendelian randomization study

Background

Nonalcoholic fatty liver disease (NAFLD) has been linked to gallstone disease (GSD) in observational studies; however, the relationships between certain lipid profiles and GSD remain unclear.

Methods

We adopted a two-sample Mendelian randomization (MR) framework by applying different statistical methods to assess causalities between lipid profiles and GSD. We identified single-nucleotide polymorphisms (SNPs) for blood lipids and NAFLD from separate previous genome-wide association studies (GWASs).

Results

We retrieved GSD SNPs attributed to 10,520 cases and 361,194 controls and validated our estimates using GWAS summary data from UK Biobank. We also performed sex-stratified analyses. Based on the summary estimates of 41, 59, 35, and 2 SNPs for low-density lipoprotein cholesterol (LDLC), high-density lipoprotein cholesterol (HDLC), triglycerides (TGs), and NAFLD, respectively, we found no evidence of a causal relationship between genetically-predicted lipid profiles and GSD. The odds ratios were 0.995 for LDLC [95% confidence interval (CI): 0.994-0.998] per 0.98 mmol/L, 0.999 for HDLC (95% CI: 0.996-1.003) per 0.41 mmol/L, 0.997 for TGs (95% CI: 0.994-1.001) per 1 mmol/L, and 0.993 for NAFLD (95% CI: 0.984-1.003). No evidence of associations between lipid profile s and GSD in validation MR analyses or the sex-stratification analyses was noted.

Conclusions

Genetically predicted hyperlipidemia or NAFLD is not causally associated with GSD.

Increasing Incidence of Gallbladder Cancer among Non-Hispanic Blacks in the United States: A Birth Cohort Phenomenon

BACKGROUND

Gallbladder cancer incidence varies among racial/ethnic subgroups in the United States (US). We investigated trends in gallbladder cancer incidence rates in 50 states from 2001 to 2018.

METHODS

Age-adjusted incidence rates and trends in adults were calculated using data from the US Cancer Statistics registry. We used joinpoint regression to compute annual percentage of changes (APC). We analyzed incidence trends by time periods, age groups, and birth cohorts through age-period-cohort modeling.

RESULTS

Overall, age standardized incidence rates for gallbladder cancer decreased by 0.3% annually between 2001 and 2018 [95% confidence interval (CI) -0.5% to -0.1%]. However, secular trends varied by race/ethnicity. Although gallbladder cancer rates declined in other racial/ethnic groups, rates increased by 1.4% annually among non-Hispanic Blacks (NHB) between 2001 and 2018 (APC = 1.4%; 95% CI, 0.9%-2.0%). We found evidence for period and birth cohort effects with increasing rates among successive birth cohorts of NHBs. Relative to NHB cohorts born circa 1946, gallbladder cancer rates were 85% higher in NHB cohorts born circa 1971 [incidence rate ratio (IRR), 1.85; 95% CI, 1.26-2.72). The rates among NHBs in South region were higher in cohorts born circa 1971 (IRR, 2.17; 95% CI, 1.27-3.73) relative to those born circa 1946.

CONCLUSIONS

The incidence of gallbladder cancer has consistently increased in the US among NHBs. A notable increase in incidence was observed among NHBs with evidence of birth cohort effects in South, Northeast, and Midwest regions.

IMPACT

The cohort effect observed among NHBs with increasing rates in different US regions suggests that gallbladder cancer rates will continue to rise in the US in the near future.

Acute Cholecystitis: A Review

IMPORTANCE

Gallbladder disease affects approximately 20 million people in the US. Acute cholecystitis is diagnosed in approximately 200 000 people in the US each year.

OBSERVATIONS

Gallstone-associated cystic duct obstruction is responsible for 90% to 95% of the cases of acute cholecystitis. Approximately 5% to 10% of patients with acute cholecystitis have acalculous cholecystitis, defined as acute inflammation of the gallbladder without gallstones, typically in the setting of severe critical illness. The typical presentation of acute cholecystitis consists of acute right upper quadrant pain, fever, and nausea that may be associated with eating and physical examination findings of right upper quadrant tenderness. Ultrasonography of the right upper quadrant has a sensitivity of approximately 81% and a specificity of approximately 83% for the diagnosis of acute cholecystitis. When an ultrasound result does not provide a definitive diagnosis, hepatobiliary scintigraphy (a nuclear medicine study that includes the intravenous injection of a radiotracer excreted in the bile) is the gold standard diagnostic test. Following diagnosis, early (performed within 1-3 days) vs late (performed after 3 days) laparoscopic cholecystectomy is associated with improved patient outcomes, including fewer composite postoperative complications (11.8% for early vs 34.4% for late), a shorter length of hospital stay (5.4 days vs 10.0 days), and lower hospital costs. During pregnancy, early laparoscopic cholecystectomy, compared with delayed operative management, is associated with a lower risk of maternal-fetal complications (1.6% for early vs 18.4% for delayed) and is recommended during all trimesters. In people older than 65 years of age, laparoscopic cholecystectomy is associated with lower mortality at 2-year follow-up (15.2%) compared with nonoperative management (29.3%). A percutaneous cholecystostomy tube, in which a drainage catheter is placed in the gallbladder lumen under image guidance, is an effective therapy for patients with an exceptionally high perioperative risk. However, percutaneous cholecystostomy tube placement in a randomized trial was associated with higher rates of postprocedural complications (65%) compared with laparoscopic cholecystectomy (12%). For patients with acalculous acute cholecystitis, percutaneous cholecystostomy tube should be reserved for patients who are severely ill at the time of diagnosis; all others should undergo a laparoscopic cholecystectomy.

CONCLUSIONS AND RELEVANCE

Acute cholecystitis, typically due to gallstone obstruction of the cystic duct, affects approximately 200 000 people in the US annually. In most patient populations, laparoscopic cholecystectomy, performed within 3 days of diagnosis, is the first-line therapy for acute cholecystitis.

Maternal smoking during pregnancy is risk factor for gallbladder disease in offspring during adulthood: a prospective study from UK Biobank

INTRODUCTION AND OBJECTIVES

Gallbladder disease is a common disease with high prevalence. Majority of gallbladder disease is due to gallstone. Though genetics are believed to play a role in its pathogenesis, the contribution of environmental pressures in early life to the development of this disease in adulthood has not been ever investigated. This study aimed to clarify the risk of maternal smoking exposure in association with gallbladder disease in adulthood. The interaction of maternal smoking and own smoking during adulthood on this association was studied as well.

PATIENTS AND METHODS

A total of 286,731 eligible participants from the UK Biobank population-based cohort were included. Multivariable Cox regression analysis were used to examine the HR and 95% CI with adjustment for covariates.

RESULT

During a median of 8.8 years follow-up, 7110 incident cases of gallbladder disease including 6800 (95.6%) gallstone were identified. Maternal smoking was associated with increased risk of incident total gallbladder disease (HR = 1.13; 95%CI: 1.06 - 1.21; P = 0.0002) as well as gallstones (HR = 1.13; 95%CI: 1.06 -1.21; P = 0.0003) in adulthood. Compared with those who were neither exposed to maternal smoking nor own smoking, subjects adherence to no smoking during adulthood but having maternal smoking exposure still had increased risk of total gallbladder disease (HR = 1.21; 95%CI: 1.1-1.34, P=0.0001) and gallstones (HR = 1.21; 95%CI: 1.1-1.35, P=0.0001).

CONCLUSION

The present study using large prospective cohort data from UK Biobank, for the first time, demonstrated maternal smoking exposure bringing elevated risk of incident total gallbladder disease/gallstone in adulthood.

A Mitochondrial DNA Variant Elevates the Risk of Gallstone Disease by Altering Mitochondrial Function

BACKGROUND AND AIMS

Gallstone disease (cholelithiasis) is a cholesterol-related metabolic disorders with strong familial predisposition. Mitochondrial DNA (mtDNA) variants accumulated during human evolution are associated with some metabolic disorders related to modified mitochondrial function. The mechanistic links between mtDNA variants and gallstone formation need further exploration.

METHODS

In this study, we explored the possible associations of mtDNA variants with gallstone disease by comparing 104 probands and 300 controls in a Chinese population. We constructed corresponding cybrids using trans-mitochondrial technology to investigate the underlying mechanisms of these associations. Mitochondrial respiratory chain complex activity and function and cholesterol metabolism were assessed in the trans-mitochondrial cell models.

RESULTS

Here, we found a significant association of mtDNA 827A>G with an increased risk of familial gallstone disease in a Chinese population (odds ratio [OR]: 4.5, 95% confidence interval [CI]: 2.1-9.4, P=1.2×10-4). Compared with 827A cybrids (haplogroups B4a and B4c), 827G cybrids (haplogroups B4b and B4d) had impaired mitochondrial respiratory chain complex activity and function and activated JNK and AMPK signaling pathways. Additionally, the 827G cybrids showed disturbances in cholesterol transport and accelerated development of gallstones. Specifically, cholesterol transport through the transporter ABCG5/8 was increased via activation of the AMPK signaling pathway in 827G cybrids.

CONCLUSIONS

Our findings reveal that mtDNA 827A>G induces aberrant mitochondrial function and abnormal cholesterol transport, resulting in increased occurrence of gallstones. The results provide an important biological basis for the clinical diagnosis and prevention of gallstone disease in the future.

Relationship between high-sensitivity C reactive protein and the risk of gallstone disease: results from the Kailuan cohort study

OBJECTIVES

Gallstone disease (GSD) can be caused by various health and clinical factors such as obesity, dyslipidaemia and an unhealthy diet, all of which are associated with higher high-sensitivity C reactive protein (hs-CRP) concentrations. Whether hs-CRP represents an independent risk factor for GSD is still unclear. We prospectively investigated hs-CRP in relation to the occurrence of GSD based on the Kailuan study.

STUDY DESIGN

Prospective cohort study.

SETTING

The Kailuan cohort study was conducted in Tangshan City in northern China.

PARTICIPANTS

95 319 participants who were free from GSD were recruited in this study. Epidemiological data, anthropometric parameters and biochemical data of participants were collected.

PRIMARY AND SECONDARY OUTCOME MEASURES

Cox proportional hazards regression models were used to evaluate the association between hs-CRP concentrations and the risk of GSD after adjustments for potential confounders.

RESULTS

During the mean 7.58 years of follow-up among 95 319 participants, 4205 participants were identified as newly diagnosed with GSD or having undergone cholecystectomy for cholelithiasis. Compared with the hs-CRP<1 mg/L group, elevated hs-CRP concentrations were significantly associated with higher risk of GSD with the corresponding HR of 1.11 (95% CI 1.03 to 1.19), 1.12 (95% CI 1.04 to 1.22) in the 1≤hs-CRP≤3 mg/L and hs-CRP>3 mg/L group, respectively. The multivariate model which included hs-CRP not only had a better line of fitness but also had better predictive values to help identify new cases of GSD during follow-up.

CONCLUSION

Elevated hs-CRP concentration is an independent risk factor for new-onset GSD among the Chinese population.

TRIAL REGISTRATION NUMBER

ChiCTR-TNC-11001489.

Funding of Hispanic/Latino Health-Related Research by the National Institutes of Health: An Analysis of the Portfolio of Research Program Grants on Six Health Topic Areas

Hispanics/Latinos are expected to constitute 25% of the U.S. population by 2060. Differences in the prevalence of health risk factors, chronic diseases, and access to and utilization of health-care services between Hispanics/Latinos and other populations in the U.S. have been documented. This study aimed to describe and analyze the landscape of Research Program Grants (RPGs) funded by the National Institutes of Health (NIH) between 2008 and 2015 involving Hispanic/Latino health research in six health condition areas-asthma, cancer, dementia, diabetes, liver/gallbladder disease, and obesity-and to identify opportunities for continued research in these areas. Using an NIH internal search engine, we identified new and renewal Hispanic/Latino health RPGs searching for specific Hispanic/Latino identifiers in the Title, Abstract, and Specific Aims. We used descriptive statistics to examine the distribution of funded RPGs by NIH disease-based classification codes for the six health condition areas of interest, and other selected characteristics. The most prominent clusters of research subtopics were identified within each health condition area, and performance sites were mapped at the city level. Within the selected time frame, 3,221 Hispanic/Latino health-related unique RPGs were funded (constituting 4.4% of all funded RPGs), and of those 625 RPGs were eligible for review and coding in the present study. Cancer and obesity were the most commonly studied health condition areas (72%), while studies on mechanisms of disease-biological and non-biological-(72.6%), behavioral research (42.1%) and epidemiological studies (38.1%) were the most common types of research. Most of the primary performance sites were in California, Texas, the northeastern U.S., and Illinois. The predominance of mechanistic, behavioral, and epidemiological studies in our analysis poses opportunities to evaluate knowledge gained and their clinical application, explore new research questions, or to update some methods or instruments. The findings of the present study suggest opportunities to expand research in understudied mechanisms of disease that could explain differences in prevalence of conditions like diabetes and cancer among different heritage groups. In addition, our findings suggest that the impact of interventions or policies designed to reduce health disparities, innovative multi-level interventions, implementation and dissemination studies, the role of health information technology on health outcomes, and the intersectionality of individual, sociocultural, geographic, and other factors on health outcomes, among others, are understudied approaches, which could potentially advance research in Hispanic/Latino health and contribute to the achievement of better health outcomes in this diverse population.

Prevalence and risk factors for gallstone disease: A population-based cross-sectional study

OBJECTIVE

To explore the prevalence of and risk factors for gallstone disease in Shanghai, China.

METHODS

A population-based cross-sectional study was conducted in Shanghai between 2016 and 2017. Using a three-stage stratified sampling strategy, 4009 participants (1753 men and 2256 women) from 10 districts were enrolled.

RESULTS

The overall prevalence of gallstones was 6.83% (6.22% for men vs 7.31% for women, P = 0.173). According to the multivariate analysis, individuals aged ≥40 years (odds ratio [OR] 3.058, 95% confidence interval [CI] 2.110-4.433, P < 0.001), hypertension (OR 1.479, 95% CI 1.076-2.034, P = 0.016), thyroid disease (OR 1.409, 95% CI 1.029-1.928, P = 0.032), a family history of gallstones (OR 2.234, 95% CI 1.362-3.662, P = 0.001) and a waist-to-height ratio ≥0.5 (OR 1.656, 95% CI 1.197-2.292, P = 0.002) had an increased risk of developing gallstones. The risk of gallstone disease was 2.232 (95% CI 1.167-4.268, P = 0.015) times higher in individuals with elevated C4 levels than in those with normal C4 levels. Diabetes (OR 4.144, 95% CI 1.171-14.671, P = 0.028) was a risk factor for the formation of gallstones with diameters ≥1 cm, and men were more susceptible to develop multiple stones (OR 2.356, 95% CI 1.321-4.200, P = 0.004).

CONCLUSION

Individuals aged ≥40 years, with a history of hypertension and familial gallstones, a high waist-to-height ratio, thyroid disease and high C4 levels were related to an increased risk of gallstone disease.

Gallbladder and Biliary Disease in Pregnancy

Diseases of the gallbladder and biliary tract are extremely common in developed nations. Because of the physiology of pregnancy, their incidence increases during gestation. This article represents a review of the existing literature on the entire spectrum of biliary disease. The physiology, clinical presentation, and diagnostic evaluation of a variety of conditions are reviewed. Historical and contemporary data regarding pregnancy implications and treatment options are discussed.

Bile Metabolism and Lithogenesis: An Update

Bile is composed of multiple macromolecules, including bile acids, free cholesterol, phospholipids, bilirubin, and inorganic ions that aid in digestion, nutrient absorption, and disposal of the insoluble products of heme catabolism. The synthesis and release of bile acids is tightly controlled and dependent on feedback mechanisms that regulate enterohepatic circulation. Alterations in bile composition, impaired gallbladder relaxation, and accelerated nucleation are the principal mechanisms leading to biliary stone formation. Various physiologic conditions and disease states alter bile composition and metabolism, thus increasing the risk of developing gallstones.

Cancer incidence among First Nations adults in Canada: follow-up of the 1991 Census Mortality Cohort (1992-2009)

OBJECTIVES

Estimate site-specific cancer incidence rates for a wide range of cancers in First Nations adults in Canada, and compare these with rates in non-Aboriginal adults.

METHODS

Responses from persons aged 25 and older to the 1991 Long Form Census were linked to national mortality and cancer databases. First Nations- and non-Aboriginal-specific incidence rates were age-standardized to the world standard population. The sex- and site-specific relative risks (RR) of cancer in First Nations compared to those in non-Aboriginal adults were estimated with Poisson regression. Results were stratified by residence on-reserve (all cancers combined) and region of Canada (four most common cancer sites).

RESULTS

Compared to non-Aboriginal adults, First Nations had higher incidence of colon and rectum, kidney, cervix, and liver cancers and lower incidence of prostate, breast, bladder, uterus, ovary, and brain cancers, as well as non-Hodgkin lymphoma, leukemia, and melanoma. First Nations women additionally had higher incidence of stomach, gallbladder, and laryngeal cancers and lower incidence of thyroid cancers compared to non-Aboriginal women. The higher relative incidence of stomach and gallbladder cancers was observed only among First Nations adults who reported living on-reserve. Incidence of lung cancer was similar for First Nations and non-Aboriginal adults nationally, though variation by region of Canada was observed.

CONCLUSION

First Nations people in Canada have disproportionately high rates of certain cancers, providing evidence to support public health policy and programming. More research is needed to identify factors contributing to the significantly lower incidence observed for various cancer types. Novel methods for studying disparities in cancer incidence among First Nations people are required to support ongoing cancer control planning and advocacy.

Role of the biliary microbiome in gallstone disease

Gallstone disease is caused by multiple pathogenic factors and is common worldwide. Most studies have focused on the significance of the biliary microbiome in gallstone pathogenesis. Areas covered: In this study, the epidemiology of gallstone diseases and the existence, composition, origin, and mechanisms of the biliary microbiota were reviewed. Mechanisms involved in promoting the formation of different types of gallstones were also emphasized. The antibiotic susceptibility of the biliary microbiota is briefly discussed because it may guide clinical strategies. Expert commentary: The biliary microbiome facilitates the formation of brown pigment stones. Although glycoprotein (mucin) may be pivotal for many promoting substances to coagulate and integrate relevant components, new mechanisms involving prostaglandins, oxysterols, oxygen free radicals, and lipopolysaccharides have been discovered. Furthermore, specific bacterial species such as Helicobacter and Salmonella are involved in the pathogenesis of cholesterol gallstones. Recently, metabolomics of the biliary microbiome has been used to determine the detailed mechanisms that promote gallstone formation. Previously, the bacterial effects involved in the pathogenesis of brown pigment stones have not been analyzed in detail. Whether the administration of antibiotics is related to prophylaxis for gallstone formation and gallstone-associated infections remains unclear.

Effects of gender and age on prevalence of cholelithiasis in patients with chronic HCV infection: A community-based cross-sectional study in an HCV-hyperendemic area

This study investigated the effects of age and gender on the prevalence of cholelithiasis in patients with chronic HCV infection.Demographic and clinical data of 8489 subjects (3671 males, 4818 females; mean age 47.5 years) receiving township-wide health examinations between September 2012 and August 2013 were analyzed. The main endpoint was prevalence of cholelithiasis. Risk factors (age, gender, body mass index, concomitant diseases, lifestyle, laboratory parameters, and HCV status) were evaluated. Univariate and multivariate logistic regression analyses were performed to identify associations between cholelithiasis and variables.Cholelithiasis was more prevalent among HCV subjects than non-HCV subjects (females: 8.1% vs 4.2%; males: 9.1% vs 3.9%; both P < .001); rates ranged from 5.6% to 8.3% in females and 4.7% to 10.6% in males. HCV status and age were associated with cholelithiasis occurrence (OR = 2.17 for HCV vs non-HCV; OR = 2.44, 3.54 for age 45-55, and >55 vs <45 years; all P < .05). Multivariate analysis showed a significant association between cholelithiasis and age/sex interaction terms (OR = 0.517 for age >55 vs <45 for sex; P = .011). Cholelithiasis prevalence was significantly associated between age and sex interaction terms but not anymore if considering positive HCV status. All noninvasive tests for liver fibrosis were associated with cholelithiasis but only fibrosis-4 index was significantly associated (OR = 1.28, P = .019).Age, gender, and HCV infection are associated with increased risk and prevalence of cholelithiasis. After age of 55 years, cholelithiasis is more prevalent among HCV-positive males than females. Females of age 55 and more may be protected against cholelithiasis as sex hormones decrease.

Analysis of gallstone disease after gastric cancer surgery

BACKGROUND

The incidence rate of newly developed gallstone disease after gastrectomy for gastric cancer is thought to be higher than that in the general population. However, the presentation and management of these gallstones remain under debate, and the role of prophylactic cholecystectomy remains questionable.

METHODS

Data on adult patients who were diagnosed with gastric cancer and received gastrectomy between 2000 and 2011 were extracted from the Taiwan National Health Insurance Research Database. A patient was excluded if he or she had gallstone disease or received cholecystectomy before the index date. The incidence of newly developed gallstone disease and its subsequent management were recorded. Data were analyzed to evaluate the factors associated with gallstone development and treatment options.

RESULTS

A total of 17,325 gastric cancer patients who underwent gastrectomy were eligible for analysis. During the follow-up period (mean 4.1 years; median, 2.9 years), 1280 (7.4%) patients developed gallstone disease and 560 (3.2%) patients subsequently underwent cholecystectomy. The in-hospital mortality for cholecystectomy was 1.8% (10/560). Development of gallstone disease was associated with older age, total gastrectomy, duodenal exclusion, diabetes, cirrhosis, and more comorbidities. Factors associated with the use of cholecystectomy to treat gallstone disease included younger age, fewer comorbidities, medical center admission, and presentation as cholecystitis.

CONCLUSIONS

Although few patients required further gallbladder removal after gastrectomy for gastric malignancy, the increased mortality rate for subsequent cholecystectomy was worth noting. The decision to undergo prophylactic cholecystectomy might be individualized based upon patient characteristics and the surgeon's discretion.

Choledocholithiasis: Treatment Options in a Tertiary Care Setup in Pakistan

Introduction Among patients with cholelithiasis, choledocholithiasis may also be present in about 18% of cases. They can be treated through various endoscopic, laparoscopic, and open surgical procedures. Objective The objective of this study was to determine the outcome of patients with choledocholithiasis being treated in our setup. Methods This descriptive case series was conducted at Holy Family Hospital, Rawalpindi, Pakistan over two years from January 2015 to December 2016. All patients with choledocholithiasis admitted to Surgical Unit 1 were included in this study. All patients underwent elective endoscopic retrograde cholangiopancreatography (ERCP). In patients with successful ERCP, laparoscopic or open cholecystectomy was performed at a later date. In patients in whom ERCP failed, open surgical clearance of the common bile duct (CBD), along with cholecystectomy, was done. Results A total of 200 cases of choledocholithiasis were admitted during the study period. Most of the participants (73%) in this study were female. Liver function tests were found to be deranged in 88 patients (44%) and normal in 112 patients (56%). At presentation, 3.5% (n=7) had concomitant acute biliary pancreatitis and 8% (n=16) had cholangitis. Successful ERCP followed by cholecystectomy was performed in 88.5% of cases. On the other hand, 11.5% (n=23) patients had failed ERCP due to impacted stones. They underwent open surgical procedures, i.e. 43.48% (n=10) had choledochotomies, 47.82% (n=11) had choledochoduodenostomies and 8.69% (n=2) had hepaticojejunostomies. No postoperative mortality was observed. However, anastomotic leaking occurred in 8.69% cases (n=2). Conclusion A two-staged procedure consisting of ERCP, followed by laparoscopic cholecystectomy, should be the first line of treatment for common bile duct (CBD) stones. In cases where ERCP fails, open surgical procedures still remain a relevant and a definitive option in resource-constrained setups.

Risk Factors for Cholelithiasis

Gallstone disease is one of the most common public health problems in the United States. Approximately 10%-20% of the national adult populations currently carry gallstones, and gallstone prevalence is rising. In addition, nearly 750,000 cholecystectomies are performed annually in the United States; direct and indirect costs of gallbladder surgery are estimated to be $6.5 billion. Cholelithiasis is also strongly associated with gallbladder, pancreatic, and colorectal cancer occurrence. Moreover, the National Institutes of Health estimates that almost 3,000 deaths (0.12% of all deaths) per year are attributed to complications of cholelithiasis and gallbladder disease. Although extensive research has tried to identify risk factors for cholelithiasis, several studies indicate that definitive findings still remain elusive. In this review, predisposing factors for cholelithiasis are identified, the pathophysiology of gallstone disease is described, and nonsurgical preventive options are discussed. Understanding the risk factors for cholelithiasis may not only be useful in assisting nurses to provide resources and education for patients who are diagnosed with gallstones, but also in developing novel preventive measures for the disease.

Physical Chemistry of Bile: Detailed Pathogenesis of Cholelithiasis

Despite the overwhelming prevalence of cholelithiasis, many health care professionals are not familiar with the basic pathophysiology of gallstone formation. This article provides an overview of the biochemical pathways related to bile, with a focus on the physical chemistry of bile. We describe the important factors in bile synthesis and secretion that affect the composition of bile and consequently its liquid state. Within this biochemical background lies the foundation for understanding the clinical and sonographic manifestation of cholelithiasis, including the pathophysiology of cholesterol crystallization, gallbladder sludge, and gallstones. There is a brief discussion of the clinical manifestations of inflammatory and obstructive cholestasis and the impact on bile metabolism and subsequently on liver function tests. Despite being the key modality in diagnosing cholelithiasis, ultrasound has a limited role in the characterization of stone composition.

Hepatitis C Virus Infection Is Positively Associated with Gallstones in Liver Cirrhosis

AIM

To elucidate the prevalence and risk factors of gallstone disease (GD) among patients with liver disease and explore their association with the aetiology and severity of hepatic injury.

METHODS

We analysed 4,832 subjects of hepatic injury induced by one of the following aetiologies: hepatitis B virus (HBV) infection, hepatitis C virus (HCV) infection, excessive alcohol consumption. The risk factors significantly associated with GD were analysed using stepwise logistic regression analysis, the influence of aetiology and severity of liver disease on the prevalence of GD were assessed by multiple logistic regression analysis adjusting for confounding factors.

RESULTS

Three thousand forty eight patients were of positive HBV surface antigen alone with a prevalence of GD of 18.6%, 526 were tested as positive Anti-HCV alone with a prevalence of GD of 22.4%, and 1,258 were identified with excessive alcohol consumption patterns with a prevalence of GD of 13.5%. In each aetiological category, the prevalence of GD increased by age. Stepwise logistic regression analysis showed that age, female, low-density lipoprotein-cholesterol (LDL-Cho), family history of GD, HBV infection, HCV infection, chronic hepatitis and cirrhosis were independent factors associated with GD. After adjusting for age, LDL-Cho and family history of GD, the prevalence of gallstone disease was significantly associated with HCV-related cirrhosis in both genders, HBV-related cirrhosis in males and alcohol-related cirrhosis in females compared with patients with less severe liver disease [corrected]. After adjusting for gender, age, LDL-Cho and family history of GD, patients with HCV-related cirrhosis (OR 2.66, 95% CI 1.49-3.84) but not HBV-related cirrhosis (OR 1.52, 95% CI 0.73-1.82) were more likely to have GD compared with alcohol-related cirrhosis.

CONCLUSION

HCV infection is positively associated with gallstone formation especially in those with cirrhosis patients.

Prevalence of Cholelithiasis Among Igbo Adult Subjects in Nnewi, Southeast Nigeria

Aim: To determine the prevalence of cholelithiasis in a Nigerian population. Subjects and Methods: A cross-sectional study of Igbo adult subjects in Nnewi, Nigeria, was conducted from June 2011 to April 2014. A sample of 3501 adult subjects’ gallbladders and associated biliary systems was evaluated by sonography, and the presence or absence of cholelithiasis was documented. The age and anthropometric variables of the subjects were recorded. Results: The subjects (18-92 years) comprised 1731 men (49.4%) and 1770 women (50.6%). Only 4.4% (n = 154) had cholelithiasis. It is more common in women than men, at a ratio of 2.8:1. It is also more common in subjects with a high body mass index. Conclusion: The prevalence of cholelithiasis among the Igbo people in Nnewi is 4.40%, and it is about three times more common in women than men.

Obesity Not Necessary, Risk of Symptomatic Cholelithiasis Increases as a Function of BMI

INTRODUCTION

Obesity is a well-established risk factor for cholelithiasis. But most of the studies have actually tried to establish the risk of cholelithiasis in overweight and obese people. Very few studies have addressed the issue of cholelithiasis in patients with otherwise normal Body Mass Index (BMI). In this study we have tried to establish if there is any relationship between increasing BMI and cholelithiasis.

AIM

To establish a relationship between increasing BMI and risk of cholelithiasis.

MATERIALS AND METHODS

Retrospective analysis was carried out after doing a prospective pilot study. Ten years data of patients admitted to surgery ward with complaints of pain abdomen was reviewed. Patients with cholelithiasis were segregated as cases and patients with some other diagnosis were selected as controls. Patients with incidental diagnosis of cholelithiasis were excluded. Appropriate analytical tools were used to draw the results using SPSS^© 20.

RESULTS

Over 11,000 patients data was reviewed and 7,182 patients were selected for inclusion into the study. Major exclusion was due to incomplete availability of data. Cholelithiasis group had 2,872 patients and rest of the patients served as controls against them. Female patients outnumbered their male counterparts in cholelithiasis group. Mean age of the gallstone patients was 37.09 years, almost 2 years younger than their controls. Mean BMI of all patients was 23.55 kg/m² and in cholelithiasis and control group was 24.93 and 22.62, respectively (df=1, F>1635.395, p<0.001). Gender specific comparison also yielded a significant difference df=3, F=547.238, p<0.001). The difference in the way the patients were distributed among the ethnic groups (Nepalis, Bhutias, Lepchas and others) was also significant (df=3, F=34.234, p<0.001). Most important outcome was that the majority of the patients in the cholelithiasis group were within the normal BMI range.

CONCLUSION

We concluded that it's not only the overweight or obese patients who develop symptomatic cholelithiasis but also the individuals with normal BMI. The risk of symptomatic cholelithiasis increases with every increase in BMI. Risk of symptomatic cholelithiasis also increases in women and as the age advances.

Gallstones

Gallstones grow inside the gallbladder or biliary tract. These stones can be asymptomatic or symptomatic; only gallstones with symptoms or complications are defined as gallstone disease. Based on their composition, gallstones are classified into cholesterol gallstones, which represent the predominant entity, and bilirubin ('pigment') stones. Black pigment stones can be caused by chronic haemolysis; brown pigment stones typically develop in obstructed and infected bile ducts. For treatment, localization of the gallstones in the biliary tract is more relevant than composition. Overall, up to 20% of adults develop gallstones and >20% of those develop symptoms or complications. Risk factors for gallstones are female sex, age, pregnancy, physical inactivity, obesity and overnutrition. Factors involved in metabolic syndrome increase the risk of developing gallstones and form the basis of primary prevention by lifestyle changes. Common mutations in the hepatic cholesterol transporter ABCG8 confer most of the genetic risk of developing gallstones, which accounts for ∼25% of the total risk. Diagnosis is mainly based on clinical symptoms, abdominal ultrasonography and liver biochemistry tests. Symptoms often precede the onset of the three common and potentially life-threatening complications of gallstones (acute cholecystitis, acute cholangitis and biliary pancreatitis). Although our knowledge on the genetics and pathophysiology of gallstones has expanded recently, current treatment algorithms remain predominantly invasive and are based on surgery. Hence, our future efforts should focus on novel preventive strategies to overcome the onset of gallstones in at-risk patients in particular, but also in the population in general.

Phase composition and morphological analysis of human gallstones using IR spectroscopy, scanning electron microscopy and X-ray Rietveld analysis

Quantitative phase composition and morphological characterization of 12 human gallbladder stones (GS1–GS12) retrieved from patients of eastern India have been carried out using IR-spectroscopy, powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM). The FTIR spectra indicated that the primary composition of gallstones studied was cholesterol. X-ray powder diffraction study revealed cholesterol monohydrate (CHM) as the major crystalline phase in GS1–GS12. The Rietveld analysis showed that nine of the gallstones were composed exclusively of CHM, while the remaining three stones contained in addition to CHM, small amounts (4.2–10.6 wt%) of calcium carbonate as aragonite and vaterite. The crystallite size of CHM in GS1–GS12 varied between 82(6) and 249(3) nm. The SEM images of gallstones showed different crystal habits of CHM such as plates, thin rods, rectangular and hexagonal blocks, which resulted into different levels of agglomeration at the mesoscopic scale. Presence of numerous parasitic eggs with a typical muskmelon surface in three gallstones (GS2, GS7 and GS9) suggests possible association between the liver fluke infection and biliary stone formation in these patients. To the best of our knowledge, the study constitutes the first report of X-ray quantitative phase analysis of gallstones using the Rietveld methodology.

Helicobacter pylori infection is associated with gallstones: Epidemiological survey in China

AIM: To elucidate the prevalence and risk factors for gallstones, primarily focusing on Helicobacter pylori (H. pylori) infection.

METHODS: A total of 10016 Chinese subjects, who had undergone physical examination, fasting ¹³C urea breath test and abdominal ultrasonography, had sufficient blood test data, and had finished a questionnaire, were included in this cross-sectional study. Participants (n = 1122) who had previous eradication of H. pylori were studied separately.

RESULTS: Gallstones were discovered in 9.10% of men and 8.58% of women, with no significant sex difference. Multivariate analyses displayed that age, aspartate aminotransferase, total cholesterol, H. pylori infection, hepatitis C virus (HCV) infection, and fatty liver had a significant association with gallstones (P < 0.05). Successive multiple logistic regression analysis including index of odds ratio (OR) and standardized coefficient (β) indicated that older age (OR/β = 1.056/0.055), H. pylori infection (OR/β = 1.454/0.109), HCV infection (OR/β = 1.871/0.123), and fatty liver (OR/β = 1.947/0.189) had a significant positive association with gallstones. After age stratification, H. pylori infection and fatty liver still had a significant positive association with gallstones in any age-specific groups, whereas HCV infection had a significant positive association in patients aged > 40 years. The prevalence of gallstones among H. pylori-positive, H. pylori-eradicated, and H. pylori-negative subjects was 9.47%, 9.02%, and 8.46%, respectively. The matched analysis showed that gallstones among H. pylori eradicated subjects was significantly lower compared with H. pylori-positive subjects (P < 0.05).

CONCLUSION: H. pylori infection and fatty liver have a significant positive association with gallstones. H. pylori eradication may lead to prevention of gallstones.

Clinical effectiveness and cost-effectiveness of cholecystectomy compared with observation/conservative management for preventing recurrent symptoms and complications in adults presenting with uncomplicated symptomatic gallstones or cholecystitis: a systematic review and economic evaluation

BACKGROUND

Approximately 10-15% of the adult population suffer from gallstone disease, cholelithiasis, with more women than men being affected. Cholecystectomy is the treatment of choice for people who present with biliary pain or acute cholecystitis and evidence of gallstones. However, some people do not experience a recurrence after an initial episode of biliary pain or cholecystitis. As most of the current research focuses on the surgical management of the disease, less attention has been dedicated to the consequences of conservative management.

OBJECTIVES

To determine the clinical effectiveness and cost-effectiveness of cholecystectomy compared with observation/conservative management in people presenting with uncomplicated symptomatic gallstones (biliary pain) or cholecystitis.

DATA SOURCES

We searched all major electronic databases (e.g. MEDLINE, EMBASE, Science Citation Index, Bioscience Information Service, Cochrane Central Register of Controlled Trials) from 1980 to September 2012 and we contacted experts in the field.

REVIEW METHODS

Evidence was considered from randomised controlled trials (RCTs) and non-randomised comparative studies that enrolled people with symptomatic gallstone disease (pain attacks only and/or acute cholecystitis). Two reviewers independently extracted data and assessed the risk of bias of included studies. Standard meta-analysis techniques were used to combine results from included studies. A de novo Markov model was developed to assess the cost-effectiveness of the interventions.

RESULTS

Two Norwegian RCTs involving 201 participants were included. Eighty-eight per cent of people randomised to surgery and 45% of people randomised to observation underwent cholecystectomy during the 14-year follow-up period. Participants randomised to observation were significantly more likely to experience gallstone-related complications [risk ratio = 6.69; 95% confidence interval (CI) 1.57 to 28.51; p = 0.01], in particular acute cholecystitis (risk ratio = 9.55; 95% CI 1.25 to 73.27; p = 0.03), and less likely to undergo surgery (risk ratio = 0.50; 95% CI 0.34 to 0.73; p = 0.0004), experience surgery-related complications (risk ratio = 0.36; 95% CI 0.16 to 0.81; p = 0.01) or, more specifically, minor surgery-related complications (risk ratio = 0.11; 95% CI 0.02 to 0.56; p = 0.008) than those randomised to surgery. Fifty-five per cent of people randomised to observation did not require an operation during the 14-year follow-up period and 12% of people randomised to cholecystectomy did not undergo the scheduled operation. The results of the economic evaluation suggest that, on average, the surgery strategy costs £1236 more per patient than the conservative management strategy but was, on average, more effective. An increase in the number of people requiring surgery while treated conservatively corresponded to a reduction in the cost-effectiveness of the conservative strategy. There was uncertainty around some of the parameters used in the economic model.

CONCLUSIONS

The results of this assessment indicate that cholecystectomy is still the treatment of choice for many symptomatic people. However, approximately half of the people in the observation group did not require surgery or suffer complications in the long term indicating that a conservative therapeutic approach may represent a valid alternative to surgery in this group of people. Owing to the dearth of current evidence in the UK setting a large, well-designed, multicentre trial is needed.

STUDY REGISTRATION

The study was registered as PROSPERO CRD42012002817.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Gallbladder Cancer Incidence and Mortality, United States 1999-2011

BACKGROUND

Gallbladder cancer is a rare cancer with unusual distribution, and few population-based estimates for the United States have been published.

METHODS

Using population-based cancer incidence and mortality data, we examined U.S. gallbladder cancer incidence and death rates for 2007-2011 and trends for 1999-2011.

RESULTS

During 2007 to 2011, approximately 3,700 persons were diagnosed with primary gallbladder cancer (rate = 1.13 cases per 100,000) and 2,000 died from the disease (rate = 0.62 deaths per 100,000) each year in the United States. Two thirds of gallbladder cancer cases and deaths occurred among women. Gallbladder cancer incidence and death rates were three times higher among American Indian and Alaska Native persons than non-Hispanic white persons. By state, gallbladder cancer incidence and death rates ranged by about 2-fold. During 1999 to 2011, gallbladder cancer incidence rates decreased among women but remained level among men; death rates declined among women but stabilized among men after declining from 1999 to 2006. Gallbladder cancer incidence rates increased in some subgroups, notably among black persons, those aged <45 years, and for endocrine tumors.

CONCLUSIONS

Data from U.S. population-based cancer registries confirm that gallbladder cancer incidence and death rates are higher among women than men, highest among American Indian and Alaska Native persons, and differ by region. While overall incidence and death rates decreased during 1999 to 2011, incidence rates increased among some small subgroups.

IMPACT

Surveillance of gallbladder cancer incidence and mortality, particularly to monitor increases in subgroups, may provide clues to etiology and stimulate further research.

The expression of hepatic carboxypeptidase E is decreased in patients with cholesterol gallstone

BACKGROUND/AIMS

Decreased carboxypeptidase E (CPE) expression is associated with numerous pathophysiological conditions. This study aimed to investigate the potential function of hepatic CPE in cholesterol gallstone formation.

PATIENTS AND METHODS

Patients with cholesterol gallstone (CGS group) and patients without cholesterol gallstones (non-CGS group) were enrolled. The serum total cholesterol, triglyceride, and biliary composition were analyzed. Eight liver samples from two patients without CGS and six patients with CGS were subjected to cDNA microarray analysis. Hepatic CPE expression was detected by quantitative real-time polymerase chain reaction (qRT-PCR), Western blot, and immunohistochemical analysis. Plasma CCK level was measured by ELISA.

RESULTS

cDNA microarray identified CPE as a gene downregulated in the CGS group. RT-PCR showed that CPE mRNA level was lower in CGS group than in control (P < 0.05, t-test). Moreover, Western blot and immunohistochemistry analysis showed that CPE protein level was significantly lower in CGS group than in the control group. In addition, plasma CCK level was lower in CGS group than in the control group. A positive correlation was found between serum CCK level and hepatic CPE mRNA level (r2 = 0.713, P = 0.003).

CONCLUSIONS

Down-expression of liver CPE may reduce the secretion of serum CCK and contribute to the formation of cholesterol gallstone.

Helicobacter pylori infection is positively associated with gallstones: a large-scale cross-sectional study in Japan

BACKGROUND

Our aim is to elucidate causative factors for gallstones, especially focusing on Helicobacter pylori (HP) infection.

METHODS

We analyzed 15,551 Japanese adults who had no history of gastrectomy, cholecystectomy, HP eradication, and didn't use proton pump inhibitors, anti-diabetic drugs, or anti-cholesterol drugs. 1,057 subjects who previously had HP eradication were analyzed separately.

RESULTS

Gallstones were detected in 409 of 8,625 men (4.74%) and 285 of 6,926 women (4.11%) by ultrasonography. Among the 25 factors univariately analyzed, age, HP infection, alcohol intake, weight, body mass index (BMI), and 14 blood test values (AST, ALT, ALP, γ-GTP, T-Chol, HDL-Chol, LDL-Chol, TG, TP, Hb, HbA1c, pepsinogen I, pepsinogen II, and pepsinogen I/II ratio) displayed significant association with gallstones (p < 0.05), whereas gender, smoking, height, and three blood test values (Alb, T-Bil, MCV) did not. Multivariate analysis showed that age, gender, alcohol intake, BMI, γ-GTP, LDL-Chol, TP, and HP infection had significant association (p < 0.05). Successive multiple logistic regression analysis calculating odds ratio (OR) and standardized coefficients (β) showed that age (OR/β = 1.57/0.450), BMI (OR/β = 1.30/0.264), HP infection (OR/β = 1.51/0.206), lower alcohol intake (OR/β = 1.33/0.144), γ-GTP (OR/β = 1.15/0.139), and pepsinogen I/II ratio (OR/β = 1.08/0.038) have significant positive association with gallstones, whereas gender does not. The gallstone prevalence among HP-negative, HP-eradicated, and HP-positive subjects was 3.81, 4.73 and 6.08%, respectively. The matched analysis controlling age, BMI, γ-GTP, alcohol intake, pepsinogen I/II ratio and gender also demonstrated that gallstone prevalence among HP-eradicated subjects was significantly lower compared with HP-positive subjects (p < 0.05).

CONCLUSIONS

HP infection is positively associated with gallstones. HP eradication may lead to prevention of gallstones.

Gallbladder cancer: epidemiology and outcome

Gallbladder cancer, though generally considered rare, is the most common malignancy of the biliary tract, accounting for 80%-95% of biliary tract cancers. An early diagnosis is essential as this malignancy progresses silently with a late diagnosis, often proving fatal. Its carcinogenesis follows a progression through a metaplasia-dysplasia-carcinoma sequence. This comprehensive review focuses on and explores the risks, management, and outcomes for primary gallbladder carcinoma. Epidemiological studies have identified striking geographic and ethnic disparities - inordinately high occurrence in American Indians, elevated in Southeast Asia, yet quite low elsewhere in the Americas and the world. Age, female sex, congenital biliary tract anomalies, and a genetic predisposition represent important risk factors that are immutable. Environmental triggers play a critical role in eliciting cancer developing in the gallbladder, best exemplified by cholelithiasis and chronic inflammation from biliary tract and parasitic infections. Mortality rates closely follow incidence; those countries with the highest prevalence of gallstones experience the greatest mortality from gallbladder cancer. Vague symptoms often delay the diagnosis of gallbladder cancer, contributing to its overall progression and poor outcome. Surgery represents the only potential for cure. Some individuals are fortunate to be incidentally found to have gallbladder cancer at the time of cholecystectomy being performed for cholelithiasis. Such an early diagnosis is imperative as a late presentation connotes advanced staging, nodal involvement, and possible recurrence following attempted resection. Overall mean survival is a mere 6 months, while 5-year survival rate is only 5%. The dismal prognosis, in part, relates to the gallbladder lacking a serosal layer adjacent to the liver, enabling hepatic invasion and metastatic progression. Improved imaging modalities are helping to diagnose patients at an earlier stage. The last decade has witnessed improved outcomes as aggressive surgical management and preoperative adjuvant therapy has helped prolong survival in patients with gallbladder cancer. In the future, the development of potential diagnostic markers for disease will yield screening opportunities for those at risk either with ethnic susceptibility or known anatomic anomalies of the biliary tract. Meanwhile, clarification of the value of prophylactic cholecystectomy should provide an opportunity for secondary prevention. Primary prevention will arrive once the predictive biomarkers and environmental risk factors are more clearly identified.

Gallbladder cancer: epidemiology and outcome

Gallbladder cancer, though generally considered rare, is the most common malignancy of the biliary tract, accounting for 80%-95% of biliary tract cancers. An early diagnosis is essential as this malignancy progresses silently with a late diagnosis, often proving fatal. Its carcinogenesis follows a progression through a metaplasia-dysplasia-carcinoma sequence. This comprehensive review focuses on and explores the risks, management, and outcomes for primary gallbladder carcinoma. Epidemiological studies have identified striking geographic and ethnic disparities - inordinately high occurrence in American Indians, elevated in Southeast Asia, yet quite low elsewhere in the Americas and the world. Age, female sex, congenital biliary tract anomalies, and a genetic predisposition represent important risk factors that are immutable. Environmental triggers play a critical role in eliciting cancer developing in the gallbladder, best exemplified by cholelithiasis and chronic inflammation from biliary tract and parasitic infections. Mortality rates closely follow incidence; those countries with the highest prevalence of gallstones experience the greatest mortality from gallbladder cancer. Vague symptoms often delay the diagnosis of gallbladder cancer, contributing to its overall progression and poor outcome. Surgery represents the only potential for cure. Some individuals are fortunate to be incidentally found to have gallbladder cancer at the time of cholecystectomy being performed for cholelithiasis. Such an early diagnosis is imperative as a late presentation connotes advanced staging, nodal involvement, and possible recurrence following attempted resection. Overall mean survival is a mere 6 months, while 5-year survival rate is only 5%. The dismal prognosis, in part, relates to the gallbladder lacking a serosal layer adjacent to the liver, enabling hepatic invasion and metastatic progression. Improved imaging modalities are helping to diagnose patients at an earlier stage. The last decade has witnessed improved outcomes as aggressive surgical management and preoperative adjuvant therapy has helped prolong survival in patients with gallbladder cancer. In the future, the development of potential diagnostic markers for disease will yield screening opportunities for those at risk either with ethnic susceptibility or known anatomic anomalies of the biliary tract. Meanwhile, clarification of the value of prophylactic cholecystectomy should provide an opportunity for secondary prevention. Primary prevention will arrive once the predictive biomarkers and environmental risk factors are more clearly identified.

Gallbladder cancer: epidemiology and outcome

Gallbladder cancer, though generally considered rare, is the most common malignancy of the biliary tract, accounting for 80%–95% of biliary tract cancers. An early diagnosis is essential as this malignancy progresses silently with a late diagnosis, often proving fatal. Its carcinogenesis follows a progression through a metaplasia–dysplasia–carcinoma sequence. This comprehensive review focuses on and explores the risks, management, and outcomes for primary gallbladder carcinoma. Epidemiological studies have identified striking geographic and ethnic disparities – inordinately high occurrence in American Indians, elevated in Southeast Asia, yet quite low elsewhere in the Americas and the world. Age, female sex, congenital biliary tract anomalies, and a genetic predisposition represent important risk factors that are immutable. Environmental triggers play a critical role in eliciting cancer developing in the gallbladder, best exemplified by cholelithiasis and chronic inflammation from biliary tract and parasitic infections. Mortality rates closely follow incidence; those countries with the highest prevalence of gallstones experience the greatest mortality from gallbladder cancer. Vague symptoms often delay the diagnosis of gallbladder cancer, contributing to its overall progression and poor outcome. Surgery represents the only potential for cure. Some individuals are fortunate to be incidentally found to have gallbladder cancer at the time of cholecystectomy being performed for cholelithiasis. Such an early diagnosis is imperative as a late presentation connotes advanced staging, nodal involvement, and possible recurrence following attempted resection. Overall mean survival is a mere 6 months, while 5-year survival rate is only 5%. The dismal prognosis, in part, relates to the gallbladder lacking a serosal layer adjacent to the liver, enabling hepatic invasion and metastatic progression. Improved imaging modalities are helping to diagnose patients at an earlier stage. The last decade has witnessed improved outcomes as aggressive surgical management and preoperative adjuvant therapy has helped prolong survival in patients with gallbladder cancer. In the future, the development of potential diagnostic markers for disease will yield screening opportunities for those at risk either with ethnic susceptibility or known anatomic anomalies of the biliary tract. Meanwhile, clarification of the value of prophylactic cholecystectomy should provide an opportunity for secondary prevention. Primary prevention will arrive once the predictive biomarkers and environmental risk factors are more clearly identified.

Lipid trait-associated genetic variation is associated with gallstone disease in the diverse Third National Health and Nutrition Examination Survey (NHANES III)

BACKGROUND

Gallstone disease is one of the most common digestive disorders, affecting more than 30 million Americans. Previous twin studies suggest a heritability of 25% for gallstone formation. To date, one genome-wide association study (GWAS) has been performed in a population of European-descent. Several candidate gene studies have been performed in various populations, but most have been inconclusive. Given that gallstones consist of up to 80% cholesterol, we hypothesized that common genetic variants associated with high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG) would also be associated with gallstone risk.

METHODS

To test this hypothesis, the Epidemiologic Architecture for Genes Linked to Environment (EAGLE) study as part of the Population Architecture using Genomics and Epidemiology (PAGE) study performed tests of association between 49 GWAS-identified lipid trait SNPs and gallstone disease in non-Hispanic whites (446 cases and 1,962 controls), non-Hispanic blacks (179 cases and 1,540 controls), and Mexican Americans (227 cases and 1,478 controls) ascertained for the population-based Third National Health and Nutrition Examination Survey (NHANES III).

RESULTS

At a liberal significance threshold of 0.05, five, four, and four SNP(s) were associated with disease risk in non-Hispanic whites, non-Hispanic blacks, and Mexican Americans, respectively. No one SNP was associated with gallstone disease risk in all three racial/ethnic groups. The most significant association was observed for ABCG5 rs6756629 in non-Hispanic whites [odds ratio (OR) = 1.89; 95% confidence interval (CI) = 1.44-2.49; p = 0.0001). ABCG5 rs6756629 is in strong linkage disequilibrium with rs11887534 (D19H), a variant previously associated with gallstone disease risk in populations of European-descent.

CONCLUSIONS

We replicated a previously associated variant for gallstone disease risk in non-Hispanic whites. Further discovery and fine-mapping efforts in diverse populations are needed to fully describe the genetic architecture of gallstone disease risk in humans.

Presence of coronary artery disease increases the risk of biliary events in patients with asymptomatic gallstones

BACKGROUND AND AIM

Propensity score indicates a probability of having a confounding factor. It is used to match each patient with the closest propensity score between two groups, which is known as propensity score matching. This study aimed to evaluate the gallstone-related biliary events, defined as biliary colic and acute cholecystitis between coronary artery disease (CAD) and non-CAD patients using propensity score matching.

METHODS

This retrospective cohort study evaluated 267 asymptomatic gallstone patients with CAD and 459 asymptomatic gallstone patients without CAD from March 2003 to December 2009 at two tertiary teaching hospitals in the Republic of Korea. After propensity score matching, total 378 patients, including 126 in study group (with CAD) and 252 in control group (without CAD), were evaluated.

RESULTS

During a median follow-up of 47 months, overall gallstone-related biliary event rate was 33.5% in the study group and 27.5% in the control group. The 5-year cumulative rates were 25.3% versus 17.7% in gallstone-related biliary event and 10.9% versus 1.6% in acute cholecystitis (study versus control group). After propensity score adjustment, the risk of gallstone-related biliary events in the CAD patients significantly increased (hazard ratio 2.11, 95% confidence interval 1.14-3.90, P = 0.017 in matched patients).

CONCLUSION

In patients with asymptomatic gallstones, the coexistence of CAD can increase the risk of gallstone-related biliary events, particularly acute cholecystitis. Therefore, gallstone patients with CAD should be carefully monitored, even if they are asymptomatic.

Genetics of gallstone disease

Gallstone disease (GSD) is one of the most common biliary tract disorders worldwide. The prevalence, however, varies from 5.9-21.9% in Western society to 3.1-10.7% in Asia. Most gallstones (75%) are silent. Approximately half of symptomatic gallstone carriers experience a second episode of biliary pain within 1 year. These individuals are at increased risk of developing acute cholecystitis, acute cholangitis, and biliary pancreatitis. As can be expected, these complications burden health care systems because of their invasive nature and surgical cost. Factors that contribute to gallstone formation include supersaturation of cholesterol in bile, gallbladder hypomotility, destabilization of bile by kinetic protein factors, and abnormal mucins. Epidemiologic studies have implicated multiple environmental factors and some common genetic elements in gallstone formation. Genetic factors that influence gallstone formation have been elaborated from linkage studies of twins, families, and ethnicities. Accumulating evidence suggests that genetic factors play a role in GSD.

Genetics of biliary lithiasis from an ethnic perspective

Gallstone disease represents one of the most common gastroenterological disorders worldwide. Gallstones affect over 15% of adults in Europe and 25-30% of Hispanic populations in Central and South America. The heritability of gallstones varies considerably according to ethnicity, with Native Americans and Hispanics with Amerindian admixture being the most susceptible populations. Genetic factors have been shown to account for 25-30% of total gallstone risk in Europe, however, in Hispanic populations, this risk percentage may increase to 45-65%. Recent genome-wide association and candidate gene studies have identified common polymorphisms in enterohepatic transporters (ABCG5/8, SLC10A2) and the Gilbert syndrome UGT1A1 variant as genetic determinants of gallstone formation. Together, these polymorphisms cover a significant proportion of the previously predicted genetic background of gallstones in European populations. New lithogenic genes need to be discovered in future studies in high-risk populations. In this review, we address the latest developments in the genetic analysis of gallstones and discuss the ethnic background of this condition in European, Central and South American and Asian populations.

Relationship between gallbladder surgery and ethnic admixture in African American and Hispanic American women

OBJECTIVES

The objective of this study was to investigate whether differences in admixture in African American and Hispanic American adult women are associated with differences in gallbladder surgery.

METHODS

Gallbladder surgery history on entry to the Women's Health Initiative's (WHI) study was used as a dichotomous outcome measure for this study. The proportion of European, sub-Saharan African, and Amerindian (AMI) admixture was estimated for 10,841 African American and 4,620 Hispanic American women in WHI using 92 ancestry informative markers. Logistic regression analyses assessed the relationship between admixture and gallbladder surgery in WHI women (enrollment at ages >50, mean age 61 years) with or without adjusting for multiple covariates, including measures of adiposity, parity, alcohol use, and education.

RESULTS

There was a significant positive association between AMI admixture and the frequency of gallbladder surgery in Hispanic Americans. The odds ratio (OR) and 95% confidence intervals (CIs) for AMI admixture group was OR=2.97, CI=2.01-4.38, P<10(-4). Although there were strong positive associations with parity and adiposity, and negative associations with alcohol consumption and education, accounting for these covariates did not remove the admixture association (OR=2.46, CI=1.62-3.73). In contrast, the effect of African admixture was nearly indistinguishable from that of the European admixture, both of which were protective in the Hispanic American group, and African admixture had a marginal association with decreased gallbladder surgery in the African American group. Measures of adiposity were associated with increased risk for gallbladder surgery and remained significant after accounting for admixture and each of the other covariates. Education level and alcohol use were associated with decreased risk for gallbladder disease. However, after accounting for the other covariates these variably remained significant.

CONCLUSIONS

AMI admixture is strongly associated with gallbladder surgery in women, even after adjustment for selected risk factors for cholelithiasis. Additional studies to ascertain the specific genetic risk factors underlying these associations are warranted.

[Obesity and gallbladder diseases]

Obesity is an important health problem in the world and related to many critical diseases, such as diabetes, cardiovascular disease, and metabolic syndrome. Obesity leads to fat infiltration of multiple organs and infiltrated adipose tissue produces many cytokines resulting in the dysfunction of organs such as the gallbladder. In the biliary diseases, obesity and overweight have been known as a major risk factor for gallstones. According to current studies, obesity, insulin resistance, hyperinsulinemia, and metabolic syndrome are related to various gallbladder diseases including gallbladder stones, cholecystitis, gallbladder polyps, and gallbladder cancers. We reviewed further literature on the obesity and gallbladder diseases, in aspects of epidemiology, mechanism, pathology and prevention.

Epidemiology of gallbladder disease: cholelithiasis and cancer

Diseases of the gallbladder are common and costly. The best epidemiological screening method to accurately determine point prevalence of gallstone disease is ultrasonography. Many risk factors for cholesterol gallstone formation are not modifiable such as ethnic background, increasing age, female gender and family history or genetics. Conversely, the modifiable risks for cholesterol gallstones are obesity, rapid weight loss and a sedentary lifestyle. The rising epidemic of obesity and the metabolic syndrome predicts an escalation of cholesterol gallstone frequency. Risk factors for biliary sludge include pregnancy, drugs like ceftiaxone, octreotide and thiazide diuretics, and total parenteral nutrition or fasting. Diseases like cirrhosis, chronic hemolysis and ileal Crohn's disease are risk factors for black pigment stones. Gallstone disease in childhood, once considered rare, has become increasingly recognized with similar risk factors as those in adults, particularly obesity. Gallbladder cancer is uncommon in developed countries. In the U.S., it accounts for only ~ 5,000 cases per year. Elsewhere, high incidence rates occur in North and South American Indians. Other than ethnicity and female gender, additional risk factors for gallbladder cancer include cholelithiasis, advancing age, chronic inflammatory conditions affecting the gallbladder, congenital biliary abnormalities, and diagnostic confusion over gallbladder polyps.

Tiny cystine stones in the gallbladder of a patient with cholecystolithiasis complicating acute cholecystitis: a case report

Cystine stones, the main component of which is cystine, are very common urinary calculi, but are rare in the gall bladder. In animals, there has been only one report of cystine gallstones in tree shrews, and to our knowledge, this is the first report of cystine gallstones in humans.

Occurrence of pancreatic, biliary tract, and gallbladder cancers in Alaska Native people, 1973-2007

Objectives

To describe the occurrence of pancreatic, biliary tract, and gallbladder cancers within the Alaska Native (AN) population.

Study design

Population-based analysis utilizing a tumor registry and comparative population data.

Methods

Pancreaticobiliary cancers rates for AN people during 1973–2007 were determined from the Surveillance, Epidemiology, and End Results (SEER) AN Tumor Registry. Cancer incidence rates were age-adjusted to the World Standard Million and compared over 2 time periods with US white and black rates.

Results

During 1973–2007, 213 AN people developed pancreatic cancer, 73 gallbladder cancer and 61 biliary tract cancer. Pancreatic cancer occurs at similar rates in AN men and women, but data for 1993–2007 indicate that the rates among AN men may be increasing. The incidence rate in AN women (9.5/100,000) was statistically higher than in US white women (5.8/100,000). The incidence for biliary tract cancer in AN men and gallbladder cancer in AN men and women is statistically higher than that for US whites and blacks.

Conclusions

Pancreaticobiliary cancers, particularly biliary tract and gallbladder cancers, in both AN men and women and pancreatic cancer in women occur at an increased rate in AN people. Risk factors relating to the elevated rate are discussed. Certain factors are potentially modifiable, such as the use of tobacco and obesity.

Concept of the pathogenesis and treatment of cholelithiasis

Gallstone disease (GD) is a chronic recurrent hepatobiliary disease, the basis for which is the impaired metabolism of cholesterol, bilirubin and bile acids, which is characterized by the formation of gallstones in the hepatic bile duct, common bile duct, or gallbladder. GD is one of the most prevalent gastrointestinal diseases with a substantial burden to health care systems. GD can result in serious outcomes, such as acute gallstone pancreatitis and gallbladder cancer. The epidemiology, pathogenesis and treatment of GD are discussed in this review. The prevalence of GD varies widely by region. The prevalence of gallstone disease has increased in recent years. This is connected with a change in lifestyle: reduction of motor activity, reduction of the physical load and changes to diets. One of the important benefits of early screening for gallstone disease is that ultrasonography can detect asymptomatic cases, which results in early treatment and the prevention of serious outcomes. The pathogenesis of GD is suggested to be multifactorial and probably develops from complex interactions between many genetic and environmental factors. It suggests that corticosteroids and oral contraceptives, which contain hormones related to steroid hormones, may be regarded as a model system of cholelithiasis development in man. The achievement in the study of the physiology of bile formation and the pathogenesis of GD has allowed expanding indications for therapeutic treatment of GD.

Molecular Mechanisms Underlying the Link between Nuclear Receptor Function and Cholesterol Gallstone Formation

Cholesterol gallstone disease is highly prevalent in western countries, particularly in women and some specific ethnic groups. The formation of water-insoluble cholesterol crystals is due to a misbalance between the three major lipids present in the bile: cholesterol, bile salts, and phospholipids. Many proteins implicated in biliary lipid secretion in the liver are regulated by several transcription factors, including nuclear receptors LXR and FXR. Human and murine genetic, physiological, pathophysiological, and pharmacological evidence is consistent with the relevance of these nuclear receptors in gallstone formation. In addition, there is emerging data that also suggests a role for estrogen receptor ESR1 in abnormal cholesterol metabolism leading to gallstone disease. A better comprehension of the role of nuclear receptor function in gallstone formation may help to design new and more effective therapeutic strategies for this highly prevalent disease condition.