Gallstone prevalence in Germany: the Ulm Gallbladder Stone Study

Mendelian randomization study on the causal relationship between food and cholelithiasis

BACKGROUND

Cholelithiasis, commonly referred to as gallstones, is a prevalent medical condition influenced by a combination of genetic factors, lifestyle choices, and dietary habits. Specific food items have been associated with an increased susceptibility to cholelithiasis, whereas others seem to offer a protective effect against its development.

METHODS

In this study, we conducted a Mendelian randomization (MR) analysis using a large-scale genetic dataset comprising individuals with European ancestry to explore the potential causal relationship between diet and cholelithiasis. The analysis incorporated 17 food-related variables, which were considered as potential factors influencing the occurrence of this condition.

RESULTS

Our findings indicate that a higher consumption of cooked vegetables, dried fruit, and oily fish is associated with a reduced risk of cholelithiasis. Conversely, a higher consumption of lamb is associated with an increased risk of developing the condition. Importantly, these associations proved robust to sensitivity and heterogeneity tests, and the pleiotropic test results further supported the hypothesis of a causal relationship between diet and cholelithiasis.

CONCLUSION

Through our study, we provide compelling evidence for the existence of a causal relationship between diet and cholelithiasis. Adopting a dietary pattern enriched with cooked vegetables, dried fruit, and oily fish, while minimizing lamb intake, may contribute to the prevention of cholelithiasis. Recognizing diet as a modifiable risk factor in the prevention and management of this condition is of paramount importance, and our study offers valuable insights in this regard.

Demographic and Risk Factor Profile in Patients of Gallstone Disease in Central India

Background Gallbladder stones are more common in some regions of the world than others. Gallstones that are asymptomatic might be discovered as an afterthought during a regular ultrasound scan for another abdominal ailment. The changing incidence in India is mostly due to westernization and the availability of ultrasonography in both urban and rural areas, as well as increased affordability owing to changes in the socio-economic structure and the budget of investigations. This study aims to know the prevalence of gallstone disease as well as the risk factors that contribute to its development in central India. Method A single-center, cross-sectional observational study was conducted. Seventy-two radiologically diagnosed cases of gallstone disease irrespective of age, gender, and comorbid condition were included in the study. Result Seventy-two cases of gallstone were included in the research. The highest age-specific incidence of gallstone was in the fifth and sixth decades with the maximum incidence in the sixth decade. Females had a higher incidence of gallstone formation. The pain was the earliest symptom but we found that 41.67% patients had asymptomatic gallstones. A family history of gallstone disease is found positive in 69.44% of the patients who also had an increased risk of gallstone. 22.22% patient were only diabetic, 6.95% were only hypertensive and 20.83% were both diabetic + hypertensive. Comorbidity has a high prevalence of gallstone disease. Obesity has a significant link to gallstone disease, with BMI being one of the most important indicators of obesity. Conclusion The prevalence of asymptomatic gallstones is relatively high in central India. We strongly recommend ultrasonography as a screening modality in patients with older age group, female gender, high cholesterol level, family history of gallstones, sickle cell disease, increased BMI and co-morbidities like diabetes or hypertension for early detection of gallstones formation.

Gallbladder stone incidence and prevalence in Germany: a population-based study

BACKGROUND

 We aimed to determine the prevalence and incidence of gallbladder stones in a random population-based collective in Germany.

METHODS

 We determined the prevalence and incidence rates of gallbladder stones in a random population sample of 1909 individuals from the Echinococcus-multilocularis in Leutkirch (EMIL) study in 2002 and 380 individuals in a follow-up analysis in the year 2013. The sonographic analysis was performed with a Philipps HDI 5000 (2002) and IU 22 (2013) (Netherlands) transducer 1-5 MHz. Statistical analysis was performed using SAS Version 9.4.

RESULTS

 The prevalence of gallbladder stones was 3.8 % (69/1909) in 2002 and 10.8 % (41/380) in 2013. In 2013, the gallbladder stone prevalence was 15.1 % (26/172) in women, compared to 7.2 % (15/208) in men. No gallbladder stones were found in participants in the 18-30 or 31-40 age groups. The average annual incidence was 1.03 % in the 41-50 age group, 0.79 % in the 51-65 age group, and 0.63 % in the > 65 age group. The annual incidence was higher among women (1.04 %) than men (0.53 %). The age-associated annual incidence rates for women and men were 1.93 % and 0.5 % in the 41-50 age group, 0.8 % and 0.78 % in the 51-65 age group, and 1.06 % and 0.30 % in the > 65 age group.

CONCLUSION

 For the investigated German collective from 2002 to 2013, the average annual incidence of gallbladder stones was 0.75 %, with a higher incidence rate among women. These results are consistent with data from comparable international studies.

Incidental Findings on Whole-body Computed Tomography in Major Trauma Patients: Who and What?

PURPOSE

Whole-body computed tomography (WBCT) scans are frequently used for trauma patients, and sometimes, nontraumatic findings are observed. We aimed to investigate the characteristics of patients with nontraumatic findings on WBCT.

METHODS

From 2013 to 2016, adult trauma patients who underwent WBCT were enrolled. The proportions of nontraumatic findings in different anatomical regions were studied. Nontraumatic findings were classified and evaluated as clinically important findings and findings that needed no further follow-up or treatment. The characteristics of the patients with nontraumatic findings were analyzed and compared with those of patients without nontraumatic findings.

RESULTS

Two hundred seventeen patients were enrolled in this study during the 3-year study period, and 89 (41.0%) patients had nontraumatic findings. Nontraumatic findings were found more frequently in the abdomen (69.2%) than in the head/neck (17.3%) and chest regions (13.5%). In total, 31.3% of the findings needed further follow-up or treatment. Patients with nontraumatic findings that needed further management were significantly older than those without nontraumatic findings (57.3 vs. 38.9; P < .001), particularly those with abdominal nontraumatic findings (57.9 vs. 41.3; P < .001). A significantly higher proportion of women were observed in the group with head/neck nontraumatic findings that needed further management than in the group without nontraumatic findings (56.3% vs 24.9%; P = .015).

CONCLUSIONS

Whole-body computed tomography could provide alternative benefits for nontraumatic findings. Whole-body computed tomography images should be read carefully for nontraumatic findings, particularly for elderly patients or the head/neck region of female patients. A comprehensive program for the follow-up of nontraumatic findings is needed.

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.

Cholesterol cholelithiasis: part of a systemic metabolic disease, prone to primary prevention

Cholesterol gallstone disease have relationships with various conditions linked with insulin resistance, but also with heart disease, atherosclerosis, and cancer. These associations derive from mechanisms active at a local (i.e. gallbladder, bile) and a systemic level and are involved in inflammation, hormones, nuclear receptors, signaling molecules, epigenetic modulation of gene expression, and gut microbiota. Despite advanced knowledge of these pathways, the available therapeutic options for symptomatic gallstone patients remain limited. Therapy includes oral litholysis by the bile acid ursodeoxycholic acid (UDCA) in a small subgroup of patients at high risk of postdissolution recurrence, or laparoscopic cholecystectomy, which is the therapeutic radical gold standard treatment. Cholecystectomy, however, may not be a neutral event, and potentially generates health problems, including the metabolic syndrome. Areas covered: Several studies on risk factors and pathogenesis of cholesterol gallstone disease, acting at a systemic level have been reviewed through a PubMed search. Authors have focused on primary prevention and novel potential therapeutic strategies. Expert commentary: The ultimate goal appears to target the manageable systemic mechanisms responsible for gallstone occurrence, pointing to primary prevention measures. Changes must target lifestyles, as well as experimenting innovative pharmacological tools in subgroups of patients at high risk of developing gallstones.

The Role of Diet in the Pathogenesis of Cholesterol Gallstones

Cholesterol gallstone disease is a major health problem in Westernized countries and depends on a complex interplay between genetic factors, lifestyle and diet, acting on specific pathogenic mechanisms. Overweigh, obesity, dyslipidemia, insulin resistance and altered cholesterol homeostasis have been linked to increased gallstone occurrence, and several studies point to a number of specific nutrients as risk- or protective factors with respect to gallstone formation in humans. There is a rising interest in the identification of common and modifiable dietetic factors that put the patients at risk of gallstones or that are able to prevent gallstone formation and growth. In particular, dietary models characterized by increased energy intake with highly refined sugars and sweet foods, high fructose intake, low fiber contents, high fat, consumption of fast food and low vitamin C intake increase the risk of gallstone formation. On the other hand, high intake of monounsaturated fats and fiber, olive oil and fish (ω-3 fatty acids) consumption, vegetable protein intake, fruit, coffee, moderate alcohol consumption and vitamin C supplementation exert a protective role. The effect of some confounding factors (e.g., physical activity) cannot be ruled out, but general recommendations about the multiple beneficial effects of diet on cholesterol gallstones must be kept in mind, in particular in groups at high risk of gallstone formation.

Association of Circulating Vitamin E (α- and γ-Tocopherol) Levels with Gallstone Disease

In addition to well-established risk factors like older age, female gender, and adiposity, oxidative stress may play a role in the pathophysiology of gallstone disease. Since vitamin E exerts important anti-oxidative functions, we hypothesized that circulating vitamin E levels might be inversely associated with prevalence of gallstone disease. In a cross-sectional study, we measured plasma levels of α- and γ-tocopherol using high performance liquid chromatography in a community-based sample (582 individuals; median age 62 years; 38.5% women). Gallstone disease status was assessed by ultrasound. Multivariable-adjusted logistic regression models were used to estimate the association of circulating α- and γ-tocopherol/cholesterol ratio levels with prevalent gallstone disease. Lower probabilities of having gallstone disease were observed in the top (compared to the bottom) tertile of the plasma α-tocopherol/cholesterol ratio in multivariable-adjusted models (OR (Odds Ratio): 0.31; 95% CI (Confidence Interval): 0.13–0.76). A lower probability of having gallstone disease was also observed for the γ-tocopherol/cholesterol ratio, though the association did not reach statistical significance (OR: 0.77; 95% CI: 0.35–1.69 for 3rd vs 1st tertile). In conclusion, our observations are consistent with the concept that higher vitamin E levels might protect from gallstone disease, a premise that needs to be further addressed in longitudinal studies.

Application of ultrasonically modified cloud point extraction method for simultaneous enrichment of cadmium and lead in sera of different types of gallstone patients

A novel and greener ultrasonically assisted/modified cloud point extraction procedure for the simultaneous preconcentration of lead and cadmium in serum samples of different types of gallstone patients was developed. The chelates of the under study metals, formerly formed with 8-hydroxyquinoline, were extracted in the micelles of a nonionic surfactant prior to analysis by flame atomic absorption spectrometer (FAAS). After the arrival of the cloud point, the critical micellar mass produced was homogenously dispersed in the aqueous phase with the help of ultrasound energy. The reliability of the developed procedure was tested by relative standard deviation (% RSD), which was found to be <5%. The performance of the proposed procedure was checked by applying to certified reference material and spiking standard in real samples. All the experimental parameters were optimized. The developed procedure of Um-CPE was applied successfully for the analysis of the target heavy metals in serum samples of different types of gallstone patients and referents. The higher levels of the understudy metals were observed in the patients as compared to the referents but the levels of the both metal were found to be considerably higher in patients with pigmented gallstones.

The Lowest Prevalence of Cholelithiasis in the Americas - An Autopsy-based Study

OBJECTIVES

This study used autopsy to evaluate the prevalence of cholelithiasis and its associated risk factors in a population of healthy, young subjects who suffered a violent or natural death.

METHODS

This study is a prospective evaluation of autopsies of 446 individuals from 2011 to 2013 in Brazil. Of that sample, 330 (74%) subjects died from violent deaths and 116 (26%) died naturally. The presence of biliary calculi, previous cholecystectomy, gender, age, ethnicity, body mass index (BMI) and alcohol use were evaluated.

RESULTS

In the natural death group, 6.9% (95% CI 3.39 to 13.28) (3.08% of the male subjects and 11.76% of the female subjects) exhibited evidence of gallbladder disease. In the violent death group, only 2.12% (95% CI 0.96 to 4.43) (2.17% of the male subjects and 1.85% of the female subjects) of the subjects exhibited evidence of gallbladder disease. Age was correlated with the prevalence of gallbladder disease, but BMI was correlated with only gallbladder disease in the natural death group.

CONCLUSIONS

This population has the lowest prevalence of cholelithiasis in the Americas. Dietary habits, physical activity, ethnicity, alcohol consumption and genetic factors may be responsible for this low prevalence.

The Prevalence and Risk Factors of Gallstone Among Adults in South-East of Iran: A Population-Based Study

Objective:

The present study aimed to evaluate the prevalence and possible risk factors of gallstone disease in the general population.

Patients and Methods:

This cross sectional study was carried out on a total of 1522 males and females aged ≥30 years in Zahedan district, South-East of Iran. Data were collected by a validated questionnaire and gallstone diagnosis was assessed by an experienced radiologist using ultrasonography. Logistic regression model was used to identify the association between selected variables and gallstone disease.

Results:

The overall prevalence of gallstone in participants was 2.4%. The risk of gallstone was 2.60 times higher in people age 45 and older than those aged 30 - 44 years (Odds Ratio = 2.60, 95% CI; 1.22 - 5.55). Females were 2.73 (95% CI; 1.34 - 5.56) times more likely to have disease compared to males as well. The risk in unmarried individuals was also three times higher than married ones (OR = 2.99: 95% CI 1.02 - 9.16). Additionally, daily physical activity reduced the risk of gallstone disease by 66% (95% CI; 0.18 - 0.86).

Conclusion:

In conclusion, increasing age and female gender were risk factors, whereas daily physical activity and marriage identified as protective factors in aetiology of gallstone disease.

Prevalence and Risk Factors of Asymptomatic Gallstone Disease in North-East Part of Bangladesh

Background

The study was designed to assess the prevalence of asymptomatic gallstone disease in North-East part of Bangladesh.

Materials and methods

Randomly selected asymptomatic persons, unknown to have gallstone disease, from both rural and urban areas were enrolled. They were subjected to abdominal ultrasonography and findings were recorded in a data sheet.

Results

Total 1,019 persons (316 males and 703 females) were examined. Age of them varied from 18 to 80 years with mean age of 37.22 years. Out of them, 61 (6%) persons were found to have gallstone. Among them, 14 were males and 47 were females. Both male and females of age below 40 years were more affected. Gallstone disease was found more commonly among housewives and middle class people. Among 61 patients with gallstone, seven were underweight (11.47%), 32 (52.45%) had normal weight and 22 (36.06%) were overweight, obese or extremely obese. But, this difference was not statistically significant (p = 0.894).

Conclusion

Prevalence of asymptomatic gallstone disease was found in 6% apparently healthy subjects of North-East part of Bangladesh. It was more prevalent among housewives and middle class group of population. It is also common among the people of age group below 40 years.

How to cite this article

Saha M, Nahar K, Hosen MMA, Khan MH, Saha SK, Shil BC, Rahman MH. Prevalence and Risk Factors of Asymptomatic Gallstone Disease in North-East Part of Bangladesh. Euroasian J Hepato-Gastroenterol 2015;5(1):1-3.

Moderate to severe, but not mild, nonalcoholic fatty liver disease associated with increased risk of gallstone disease

OBJECTIVE

Nonalcoholic fatty liver disease (NAFLD) and gallstone disease (GSD) share some of the same risk factors. The association between NAFLD and GSD was inconsistent. Moreover, there are no studies on the association between GSD and the severity of NAFLD in the literature. The aim of this study was to determine the relationship between the severity of NAFLD and GSD in a Taiwanese population.

MATERIALS AND METHODS

A total of 12,033 subjects were enrolled. The diagnoses of GSD and NAFLD were based on the finding of abdominal ultrasonography. The severity of NAFLD was divided into mild, moderate, and severe.

RESULTS

Compared with the non-GSD group, the GSD one was older and had a higher BMI, blood pressure, fasting plasma glucose, cholesterol, triglyceride, and higher prevalence of diabetes and hypertension, but they had a lower eGFR and HDL-C level and less prevalence of current smoking and alcohol drinking. There was a significant difference in the severity of NAFLD between subjects with and without GSD. Based on logistic regression, age ≥65 versus <40 years, 40-64.9 versus <40 years, female, current alcohol drinking, diabetes, hypertension, HDL-C level and moderate to severe NAFLD, but not mild NAFLD, were the independently associated risk factors of GSD.

CONCLUSION

Moderate to severe, but not mild, NAFLD was associated with an increased risk of GSD, independent of the traditional cardio-metabolic risk factor. Age, female, diabetes, and hypertension were also related to a higher risk of GSD, but HDL-C level and moderate alcohol drinking showed a lower risk.

Gallstones

Gallstone disease is a worldwide medical problem, but the incidence rates show substantial geographical variation, with the lowest rates reported in African populations. Publications in English language on gallstones which were obtained from reprint requests and PubMed database formed the basis for this paper. Data extracted from these sources included authors, country, year of publication, age and sex of patients, pathogenesis, risk factors for development of gallstones, racial distribution, presenting symptoms, complications and treatment. Gallstones occur worldwide, however it is commonest among North American Indians and Hispanics but low in Asian and African populations. High biliary protein and lipid concentrations are risk factors for the formation of gallstones, while gallbladder sludge is thought to be the usual precursor of gallstones. Biliary calcium concentration plays a part in bilirubin precipitation and gallstone calcification. Treatment of gallstones should be reserved for those with symptomatic disease, while prophylactic cholecystectomy is recommended for specific groups like children, those with sickle cell disease and those undergoing weight-loss surgical treatments. Treatment should be undertaken for a little percentage of patients with gallstones, as majority of those who harbor them never develop symptoms. The group that should undergo cholecystectomy include those with symptomatic gallstones, sickle cell disease patients with gall stones, and patients with morbid obesity who are undergoing laparotomy for other reasons.

Genetic and functional identification of the likely causative variant for cholesterol gallstone disease at the ABCG5/8 lithogenic locus

The sterolin locus (ABCG5/ABCG8) confers susceptibility for cholesterol gallstone disease in humans. Both the responsible variant and the molecular mechanism causing an increased incidence of gallstones in these patients have as yet not been identified. Genetic mapping utilized patient samples from Germany (2,808 cases, 2,089 controls), Chile (680 cases, 442 controls), Denmark (366 cases, 766 controls), India (247 cases, 224 controls), and China (280 cases, 244 controls). Analysis of allelic imbalance in complementary DNA (cDNA) samples from human liver (n = 22) was performed using pyrosequencing. Transiently transfected HEK293 cells were used for [(3) H]-cholesterol export assays, analysis of protein expression, and localization of allelic constructs. Through fine mapping in German and Chilean samples, an ∼250 kB disease-associated interval could be defined for this locus. Lack of allelic imbalance or allelic splicing of the ABCG5 and ABCG8 transcripts in human liver limited the search to coding single nucleotide polymorphisms. Subsequent mutation detection and genotyping yielded two disease-associated variants: ABCG5-R50C (P = 4.94 × 10(-9) ) and ABCG8-D19H (P = 1.74 × 10(-10) ) in high pairwise linkage disequilibrium (r(2) = 0.95). [(3) H]-cholesterol export assays of allelic constructs harboring these genetic candidate variants demonstrated increased transport activity (3.2-fold, P = 0.003) only for the ABCG8-19H variant, which was also superior in nested logistic regression models in German (P = 0.018), Chilean (P = 0.030), and Chinese (P = 0.040) patient samples.

CONCLUSION

This variant thus provides a molecular basis for biliary cholesterol hypersecretion as the mechanism for cholesterol gallstone formation, thereby drawing a link between "postgenomic" and "pregenomic" pathophysiological knowledge about this common complex disorder. (HEPATOLOGY 2012).

Impact of risk factors for prolonged operative time in laparoscopic cholecystectomy

OBJECTIVE

Laparoscopic cholecystectomy (LC) remains one of the most frequent surgical therapies for symptomatic gallstone disorders. Prolonged operative time is frequently associated with increased complication rates. The aim of this study was to identify the risk factors for prolonged operative times to minimize perioperative morbidity and optimize clinical management.

METHODS

A total of 677 consecutive patients underwent LC. The exclusion criteria were conversion to an open procedure, intraoperative cholangiography, and liver cirrhosis (n=81). Data were analyzed retrospectively with respect to age, sex, BMI, ASA score, previous abdominal surgery, preoperative endoscopic retrograde cholangiopancreatography, acute cholecystitis, and surgeon's experience. Univariate and multivariate analyses were performed.

RESULTS

A total of 596 patients, mean (± SD) age of 52.2 ± 16.7 years, were analyzed. In all, 29% of the patients were obese (BMI ≥ 30 kg/m); 11% had ASA III. Five percent of patients had undergone previous upper abdominal surgery. Overall, 105/596 patients had an acute cholecystitis. Residents of general surgery performed 58% of all operations. The median operative time was 80 min (range, 15-281 min). No statistical significance was found between intraoperative and postoperative complications by surgeon's experience. Statistically, independent preoperative predictors for prolonged operative time as identified through multivariate analysis were acute cholecystitis, obesity, previous upper abdominal surgery, male sex, and low degree of surgical expertise.

CONCLUSION

The risk for prolonged operative times in LC can be assessed on the basis of patients' characteristics. Assessment of these factors not only helps to optimize the individual outcome for each patient but also improves the decision process toward operative training for junior surgeons.

Loci from a genome-wide analysis of bilirubin levels are associated with gallstone risk and composition

BACKGROUND & AIMS

Genome-wide association studies have mapped loci that are associated with serum levels of bilirubin. Bilirubin is a major component of gallstones so we investigated whether these variants predict gallstone bilirubin content and overall risk for gallstones.

METHODS

Loci that were identified in a meta-analysis to attain a genome-wide significance level of a P value less than 1.0×10(-7) (UGT1A1, SLCO1B1, LST-3TM12, SLCO1A2) were analyzed in 1018 individuals with known gallstone composition. Gallstone risk was analyzed in 2606 German choleystecomized individuals and 1121 controls and was replicated in 210 cases and 496 controls from South America.

RESULTS

By using the presence of bilirubin as a phenotype, variants rs6742078 (UGT1A1; P = .003), rs4149056 (SLCO1B1; P = .003), and rs4149000 (SLCO1A2; P = .015) were associated with gallstone composition. In regression analyses, only UGT1A1 and SLCO1B1 were independently retained in the model. UGT1A1 (rs6742078; P = .018) was associated with overall gallstone risk. In a sex-stratified analysis, only male carriers of rs6742078 had an increased risk for gallstone disease (P = 2.1×10(-7); odds ratio(recessive), 2.34; P(women) = .47). The sex-specific association of rs6742078 was confirmed in samples from South America (P(men) = .046; odds ratio(recessive), 2.19; P(women) = .96).

CONCLUSIONS

The UGT1A1 Gilbert syndrome variant rs6742078 is associated with gallstone disease in men; further studies are required regarding the sex-specific physiology of bilirubin and bile acid metabolism. Variants of ABCG8 and UGT1A1 are the 2 major risk factors for overall gallstone disease, they contribute a population attributable risk of 21.2% among men.

The effect of alcohol, tobacco and caffeine consumption and vegetarian diet on gallstone prevalence

AIM

To investigate the effects of alcohol, tobacco and caffeine consumption and of vegetarian diet on gallstone prevalence in an urban population sample.

METHODS

A total of 2417 individuals underwent ultrasound examination and completed a standardized questionnaire as part of the EMIL study. Statistical analysis of the data considered the known risk factors of age, female sex, BMI, positive family history and potential confounders, such as alcohol, caffeine and tobacco consumption and vegetarian diet using multiple logistic regression with variable selection.

RESULTS

The prevalence of gallstones in the population sample was 8% (171 out of 2147). Findings of the study confirmed the classic risk factors of age, female sex, obesity and positive family history. After the variable selection of potential risk factors in a logistic regression that was adjusted for age, female sex, BMI and positive family history, the factors like tobacco [odds ratio (OR) 1.09, 95% confidence interval (CI): 0.76-1.56, P=0.64] and caffeine consumption (OR: 0.77, 95% CI: 0.42-1.42, P=0.40) as well as vegetarian diet (OR: 1.14, 95% CI: 0.39-3.35, P=0.81) had no effect on gallstone prevalence. A protective effect against development of gallstones was shown for alcohol consumption (OR: 0.67, 95% CI: 0.46-0.99, P=0.04).

CONCLUSION

The factors like tobacco and caffeine consumption as well as vegetarian diet exerted no measurable effect on the prevalence of gallstones. A protective effect was found for alcohol consumption.

Incidence of and potential risk factors for gallstone disease in a general population sample

BACKGROUND

Several epidemiological studies have been published, but there are few reports on relations between gallstone incidence, symptomatology and risk factors.

METHODS

Of 621 randomly selected individuals aged 35-85 years in a general population who had been screened previously with ultrasonography and found to have no gallbladder stones, 503 (81.0 per cent) were re-examined after a minimum interval of 5 years. At baseline and re-examination, heredity for gallstone disease was explored and body mass index, digestive symptoms including abdominal pain, quality of life, alcohol and smoking habits, use of non-steroidal anti-inflammatory drugs and oestrogen, parity and blood lipid levels were recorded.

RESULTS

Forty-two (8.3 per cent) of the 503 subjects developed stones. Subjects were followed for a total of 3025.8 person-years, yielding an incidence for newly developed gallstones of 1.39 per 100 person-years. A positive association for gallstone development was found only for length of follow-up and plasma low-density lipoprotein-cholesterol levels at baseline. Weekly alcohol consumption was inversely related to gallstone development.

CONCLUSION

The incidence of gallstones in this population was 1.39 per 100 person-years. Gallstone development was related to length of follow-up and LDL-cholesterol levels, and inversely related to alcohol consumption.

The prevalence and risk factors for gallstone disease

Gallstone disease is one of the most prevalent gastrointestinal disorders. In addition, the costs associated with the diagnosis and treatment of gallstone disease have been rapidly increasing. The etiology and pathogenesis of gallstone disease remains incompletely understood. Gallstone formation may result from a complex interaction of genetic and environmental factors. This article reviews the prevalence and risk factors associated with gallstone disease. Understanding the pathogenesis of gallstone disease could lead to the development of better therapeutic and preventive strategies for dealing with this disease.

Cholesterol 7alpha-hydrolase (CYP7A1) c.-278A>C promoter polymorphism in gallstone disease patients

There is growing evidence that gallstone formation may be genetically determined. Cholesterol 7alpha-hydrolase (CYP7A1) is an enzyme that catalyzes the first, rate-limiting reaction of cholesterol catabolic pathway. Recently, a common c.-278A>C polymorphism (rs3808607:G>T) has been described in CYP7A1 gene, associated with altered plasma lipid levels. The aim of this study was to verify the finding that CYP7A1 polymorphism may be associated with gallstone disease. Frequency and distribution of the studied alleles did not differ significantly between the patients (-278C; minor allele frequency: 0.45) and the controls (0.48). No significant gender-related differences of allele frequencies or distribution were noted. We conclude that CYP7A1 promoter polymorphism is not a valuable marker of gallstone disease susceptibility in a Polish population.

Low-density lipoprotein receptor-related protein-associated protein (LRPAP1) gene IVS5 insertion/deletion polymorphism is not a risk factor for gallstone disease in a Polish population

BACKGROUND

There is growing evidence that gallstone formation may be genetically determined. It was recently presented that a common polymorphism in the LRPAP1 gene might be associated with gallstone disease.

AIM

Since reproducibility of data is important in genetic association studies, a case control study was designed to find out whether LRPAP1 gene polymorphism is associated with gallstone disease in a Polish population.

SUBJECTS

Two hundred eighty-nine Polish Caucasian gallstone disease patients and 251 healthy controls participated in the study.

METHODS

A 37-bp insertion/deletion polymorphism in intron 5 of LRPAP1 (rs11267919) was determined by means of polymerase chain reaction assay.

RESULTS

The frequencies and distribution of the insertion/deletion alleles did not differ significantly between gallstone disease patients and controls. No significant gender-related differences in allele frequencies or distributions were noted.

CONCLUSION

The LRPAP1 insertion/deletion polymorphism is not associated with gallstone disease in a Polish population.

Gallstone analysis using Fourier transform infrared spectroscopy (FT-IR)

BACKGROUND

Gallstone analysis is important in determining the possible etiology of stone formation and the pathophysiology of cholelithiasis. Physical analysis using Fourier transform infrared spectroscopy (FT-IR), compared to chemical analysis, requires minimal sample volume, shows uniform sensitivity and specificity for all components and provides quantitative results with greater reproducibility. We studied the characteristics and distribution of gallstones using FT-IR in addition to the risk factors for gallstone formation in Korean patients. A better understanding of the mechanism underlying stone formation may help prevent gallstone development.

METHODS

Physical analysis of gallstones in 490 patients who underwent cholecystectomy was carried out using the FT-IR system 2000 (Perkin-Elmer Co.) and Spectrum software (Perkin-Elmer Co.). Visual inspection of the size, color, consistency and surface of the stones was compared with the physical characteristics. Clinical, demographic and laboratory findings were evaluated and compared with the gallstone components.

RESULTS

The FT-IR evaluation showed that most gallstones were composed of a single component (84.1%); cholesterol was the most commonly observed element among the major components (50%, 245/490). Morphological classification according to color, consistency and surface was different from the FT-IR composition analysis. There were significant differences in the components based on age, obesity, education level and the presence of diabetes mellitus.

CONCLUSIONS

The results of this study show that physical analysis of gallstones with FT-IR provides important information on stone composition, distribution and risk factors. These study results will help improve our understanding of the pathophysiology of gallstone disease in the Korean population, where there is a high frequency of hepatobiliary disorders.

Investigation of the Lith6 candidate genes APOBEC1 and PPARG in human gallstone disease

BACKGROUND

Genetic susceptibility contributes to the aetiology of gallbladder diseases as shown by multiple epidemiological studies. A major gallstone susceptibility locus (Lith6) was identified in 2003 by quantitative trait locus mapping in mice. Two attractive positional and functional candidate genes in apolipoprotein B mRNA-editing protein (APOBEC1) and peroxisome proliferator-activated receptor gamma (PPARG) are located in this interval.

AIMS

To investigate APOBEC1 and PPARG as candidate genes for common symptomatic gallstone disease in humans.

PATIENTS AND METHODS

Eight hundred and ten patients who underwent cholecystectomy for symptomatic gallstone disease (median age of onset 50) were compared with 718 sex-matched control individuals. An independent additional sample included 368 gallstone patients and 368 controls. Control individuals were sonographically free of gallstones. Haplotype tagging and all known coding single nucleotide polymorphisms were genotyped for PPARG (N=32) and APOBEC1 (N=11).

RESULTS

The investigated high-risk patient sample provides a power of greater than 80% for the detection of odds ratios down to 1.45. No evidence of association of the two genes in the single-point tagging markers, coding variants and in the sliding window haplotype analysis was detected (all nominal single point P-values >0.04). A logistic regression analysis including age, sex and BMI as covariates was also negative (nominal P-values > or =0.08).

CONCLUSIONS

In the investigated German samples, no evidence of association of APOBEC1 and PPARG with gallstone susceptibility was detected. Systematic fine mapping of the complete Lith6 region is required to identify the causative genetic variants for gallstone in mice and humans.

Family history of gallstones and the risk of biliary tract cancer and gallstones: a population-based study in Shanghai, China

Cancers of the biliary tract arise from the gallbladder, extrahepatic bile ducts and ampulla of Vater. Although relatively uncommon, the incidence of biliary tract cancer rose more than 100% in Shanghai, China between 1972 and 1994. Gallstones are the predominant risk factor for biliary tract cancers, with over 60% of the cancer cases having gallstones. A familial tendency to gallstones has been reported and may elevate the risk of gallbladder cancer further. As part of a large population-based case-control study of biliary tract cancers in Shanghai, China, we examined the association between a family history of gallstones and biliary tract cancers as well as biliary stones. A total of 627 biliary tract cancers (368 gallbladder, 191 bile duct, 68 ampulla of Vater), 1,037 biliary stone cases (774 gallbladder, 263 bile duct) and 959 healthy subjects randomly selected from the population were included in this study. Information on family history of gallstones among first-degree relatives (i.e., parents, siblings, offspring) was obtained through a self-reported history during in-person interviews. A family history of gallstones was associated with increased risks of biliary stones [odds ratio (OR) = 2.8, 95% confidence interval (CI) = 2.1-3.8], gallbladder cancer (OR = 2.1, 95% CI = 1.4-3.3) and bile duct cancer (OR = 1.5, 95% CI = 0.9-2.5), after adjustment for age, gender, marital status, education, smoking, alcohol drinking and body mass index. For gallbladder cancer, subjects with gallstones but without a family history of gallstones had a 21-fold risk (95% CI 14.8-30.1), while those with both gallstones and a positive family history had a 57-fold risk (95% CI 32.0-110.5). Significant risks for gallbladder cancer persisted after additional adjustment for gallstones, and when the analysis was restricted to subjects with first-degree relatives whose gallstones were treated with cholecystectomy. The significant associations with a family history of gallstones were seen for all first-degree relatives, including parents, siblings and offspring, but not spouses. This large population-based study not only supports the role of gallstones in biliary carcinogenesis but also suggests that the underlying genetic or lifestyle determinants of stones within families contribute to the risk of biliary tract cancer.

Menopausal hormone therapy and gallbladder disease: the Study of Health in Pomerania (SHIP)

OBJECTIVE

Several studies suggest that oral menopausal hormone therapy (MHT) is associated with an increased risk of gallbladder disease. It has been hypothesized that nonoral MHT may reduce the risk of cholelithiasis. The objective of the present study was to analyse the association between (1) use of life-time MHT (ever use) and gallbladder disease and (2) nonoral use of MHT and gallbladder disease.

DESIGN

Cross-sectional study using population-based data from the Study of Health in Pomerania (SHIP).

POPULATION

The study population included 994 postmenopausal women, aged 40-79 years. The subgroup of current oral and nonoral MHT users comprised 139 women.

METHODS AND MEASUREMENTS

Sociodemographic, medical and reproductive characteristics were based on computer-assisted personal interviews, and selected laboratory parameters were analysed. Gallbladder disease was defined by either a prior history of cholecystectomy or the presence of current sonographically diagnosed gallstones. Data analyses consisted of descriptive, bivariable and multivariable procedures. We performed Poisson regression with Huber/White standard errors to investigate the association between ever use, current nonoral use of MHT and gallbladder disease.

RESULTS

We found no significant association between ever use of MHT and gallbladder disease and sonographically diagnosed gallstones in fully adjusted analyses. Women who used MHT had a significantly higher risk for cholecystectomy compared to nonusers. There was no association between nonoral use of MHT and gallbladder disease.

CONCLUSIONS

Our analyses do not lend support to the hypothesis that use of MHT is associated with gallbladder disease.

Apolipoprotein B (APOB) Gene Polymorphism in Patients with Gallbladder Disease

Cholelithiasis is one of the most prevalent gastroenterological diseases, precipitated mainly by environmental factors. However, twin studies provided strong evidence for a role of genetic factors in the disease pathogenesis. An association between plasma lipoprotein levels and gallstone disease (GSD) was presented. Apolipoprotein B is an essential structural component of triglyceride-rich lipoprotein particles and plays an important role in the maintenance of cholesterol homeostasis in mammals. Various studies have shown a relationship between APOB gene polymorphisms and lipoprotein levels, but only few investigated a potential association between APOB polymorphism and GSD, giving contrary results. In the current study, an association between common polymorphisms in APOB gene (T2488T and E4154K) and cholesterol gallstone disease was examined. Two hundred and forty patients of Caucasian origin suffering from cholelithiasis, as well as 217 healthy individuals, were included in the study. Patients were genotyped for two single nucleotide polymorphisms (SNPs) in APOB gene: 2488C>T (XbaI), and 4154G>A (EcoRI) using PCR-RLFP method. The resulting analysis has shown that polymorphic loci in positions 2488 and 4154 in APOB gene are in full linkage in a Polish population and form only three haplotypes: 2488C-4154G, 2488T-4154G and 2488C-4154A. Frequency and distribution of 2488C>T alleles did not differ significantly between patients and controls. The 4154G allele has been found to be associated with GSD (p=0.001). A risk of gallstone formation was reduced in 4154AA homozygotes (OR=0.25, p=0.009) and heterozygous individuals (OR=0.63, p=0.03) as compared to 4154GG homozygotes. Additionally, 2488C-4154A haplotype was identified as a protective factor against GSD (p=0.04). Our results suggest that SNPs in APOB, potentially considered as one of lith genes as well as certain haplotypes, may be risk factors for GSD.

Investigation of the Lith1 candidate genes ABCB11 and LXRA in human gallstone disease

Genetic susceptibility in the causation of gallbladder diseases was recognized as early as 1937. A major gallstone susceptibility locus (Lith1) was identified in 1995 by quantitative trait locus mapping in mice. Two attractive positional and functional candidate genes in LXRA and ABCB11 are located in this interval. ABCB11 is associated with progressive familial cholestasis. This study was undertaken to investigate LXRA and ABCB11 as candidate genes for gallstone disease in humans. Eight hundred and ten patients who underwent cholecystectomy for symptomatic gallstone disease (median age of onset, 50 years) were compared with 718 sex-matched control individuals. Control individuals were sonographically free of gallstones. Haplotype tagging and all known coding single nucleotide polymorphisms (SNPs) were genotyped for ABCB11 (n=29) and LXRA (n=10). The investigated high-risk patient sample provides a power of greater than 80% for the detection of odds ratios down to 1.55. No evidence of association of the two genes in the single point tagging markers, coding variants or in the sliding window haplotype analysis was detected (all nominal single-point P values>or=.08). In conclusion, in the investigated German sample, no evidence of association of ABCB11 and LXRA to gallstone susceptibility was detected. The gallstone trait is not allelic to progressive familial cholestasis at the ABCB11 locus. Systematic fine mapping of the Lith1 region is required to identify the causative genetic variants for gallstone in mice and humans.

Innovations in Treating the Elderly Who Have Biliary and Pancreatic Disease

Many diseases of the biliary tract and pancreas preferentially effect the elderly. Recent innovations in the evaluation and management of these disorders have directly impacted the lives of many seniors. Improved outcomes of pancreatic surgery is a good example of a positive impact in quality of life, especially when these surgeries are performed in centers of excellence. Evaluation and treatment strategies are presented for complicated calculous biliary disease, pancreatic carcinoma, and pancreatic cystic neoplasms.

Impact of body overweight and class I, II and III obesity on the outcome of acute biliary pancreatitis

OBJECTIVES

Body overweight and obesity have been associated with an increased morbidity in acute pancreatitis, but conflicting results were reported in the literature with regard to the type and frequency of complications. We investigated the occurrence of complications in different classes of overweight in a homogeneous group of patients with gallstone pancreatitis.

METHODS

Data were collected prospectively from 250 patients with biliary pancreatitis to allow calculation of the Blamey (Glasgow) and Acute Physiology and Chronic Health Evaluation (APACHE II) scores. According to their body mass index (BMI), the patients were allocated to different categories of body overweight. The outcome for each category was measured by the components of the Atlanta criteria. Secondary end points of the study were the length of hospital stay, the length of stay at the intensive care unit, and the number of abdominal operations.

RESULTS

When compared with normal-weight patients (BMI 18.5-24.9), all categories with BMI > or =25 had an increased risk of developing the "severe" form of acute pancreatitis [odds ratio (OR): 3.55, 95% confidence interval (CI): 1.50-8.40]. Patients with class I obesity (BMI 30-34.9) developed significantly more organ failure and local complications (OR: 3.469, 95% CI: 1.15-10.43). Patients with class II and III obesity (BMI 35-49.9) had, in addition to more organ failure and local complications, also more metabolic complications (OR: 7.33, 95% CI: 1.62-33.24) than did their normal-weight counterparts. They needed also more frequently intensive care and had a longer total hospital stay.

CONCLUSION

In acute biliary pancreatitis, body overweight and obesity represent a risk of more "severe" disease and the number and type of complications increase in categories of increasing BMI.

Pregnancy is not a risk factor for gallstone disease: Results of a randomly selected population sample

AIM: To investigate the prevalence, risk factors, and selection of the study population for cholecystolithiasis in an urban population in Germany, in relation to our own findings and to the results in the international literature.

METHODS: A total of 2 147 persons (1 111 females, age 42.8 ± 12.7 years; 1 036 males, age 42.3 ± 13.1 years) participating in an investigation on the prevalence of Echinococcus multilocularis were studied for risk factors and prevalence of gallbladder stone disease. Risk factors were assessed by means of a standardized interview and calculation of body mass index (BMI). A diagnostic ultrasound examination of the gallbladder was performed. Data were analyzed by multiple logistic regression, using the SAS statistical software package.

RESULTS: Gallbladder stones were detected in 171 study participants (8.0%, n = 2 147). Risk factors for the development of gallbladder stone disease included age, sex, BMI, and positive family history. In a separate analysis of female study participants, pregnancy (yes/no) and number of pregnancies did not exert any influence.

CONCLUSION: Findings of the present study confirm that age, female sex, BMI, and positive family history are risk factors for the development of gallbladder stone disease. Pregnancy and the number of pregnancies, however, could not be shown to be risk factors. There seem to be no differences in the respective prevalence for gallbladder stone disease in urban and rural populations.

[Nononcologic abdominal surgery in the elderly]

Due to rising life expectancy of the population, the proportion of elderly patients requiring surgery is rising as well. Present aspects of selected, typical, nononcologic diseases of elderly people are discussed. The key to success in their treatment is not to consider primarily the patient's calendrical age but to assess the individual profile of risk factors on the basis of comorbidities. The kind, extent, and timing of an operation has to be based on this assessment. For the treatment of acute diseases (e.g., complicated ulcera, cholecystitis, appendicitis, mesenteric ischemia, and diverticulitis), a rapid and efficacious diagnostic algorithm is essential that takes into account the reduced functional reserve of old people. Constructive interdisciplinary cooperation and minimally invasive techniques play dominant roles in both diagnosis and therapy. Given these prerequisites, there is no reason to withhold surgical intervention from elderly patients.

Hepatic canalicular membrane transport of bile salt in C57L/J and AKR/J mice: implications for cholesterol gallstone formation

C57L/J (gallstone-susceptible) and AKR/J (gallstone-resistant) mice have been utilized for quantitative trait loci (QTL) analysis to identify the Lith 1 locus for cholelithiasis. Abcb11 encodes for the liver canalicular membrane bile salt export pump (BSEP), which maps to this QTL and is a candidate gene for Lith 1. We investigated the transmembrane transport of taurocholate in canalicular liver membrane vesicles isolated from these murine strains. Canalicular liver plasma membranes (cLPM) and RNA were isolated from C57L/J and AKR/J mice livers, and were utilized for Northern and Western blot analysis and functional (3)H-taurocholate uptake studies. ATP-dependent (3)H-taurocholate uptake was significantly higher in AKR/J, compared to C57L/J mice. V(max) was 127 vs. 42 pmol TC/mg/s in the murine strains, respectively, while K(m) was unchanged. In contrast, gene and protein expression of hepatic Abcb11 was increased three-fold in C57L/J, compared to AKR/J mice. Thus, Abcb11 bile salt transport activity per unit protein was reduced nine-fold in the C57L/J, compared to AKR/J mice. In contrast, canalicular membrane cholesterol:phospholipid content was also significantly higher in the C57L/J mice. We conclude that gallstone-susceptible C57L/J mice demonstrate increased gene and canalicular membrane expression of Abcb11, however, taurocholate transport is functionally diminished. The latter may be due to the increased cholesterol membrane content of the cLPM in C57L/J mice. These findings may be important for the pathogenesis of gallstone formation.

Gallstones: genetics versus environment

OBJECTIVE

The aim of this study was to determine if a significant genetic component contributes to the pathogenesis of symptomatic gallstones.

SUMMARY BACKGROUND DATA

Gallstones represent a polygenic disorder that affects more than 30,000,000 Americans and results in more than 750,000 cholecystectomies in the United States annually. Risk factors include age, gender, race, parity, obesity, and diabetes. A family history of gallstones also has been identified as a risk factor suggesting that genetics play a role in gallstone formation. However, the role of genetics in the pathogenesis of gallstone formation has not been determined.

METHODS

A gallbladder disease-specific questionnaire was administered to 904 healthy unrelated adult volunteers (association study). The questionnaire ascertained a history of cholecystectomy and gallstone disease in first-degree relatives, as well as medical history, demographic, and anthropometric data. A logistic regression model was used to identify risk factors for symptomatic gallstone disease in a multivariate analysis. A maximum likelihood based variance decomposition approach was then used in 1,038 individuals from 358 families (family study) to estimate the additive genetic heritability of symptomatic gallstone disease.

RESULTS

In the association study significant risk factors for symptomatic gallstone disease were female gender (relative risk 8.8, P <.003), obesity (BMI > 30, relative risk 3.7, P <.001), age > 50 (relative risk 2.5, P <.001), and a positive family history of previous cholecystectomy in a first-degree family member (relative risk 2.2, P <.01). In the family study the additive genetic heritability of symptomatic gallstones was 29% (P <.02), age and gender were significant covariates and explained 9.3% of the phenotypic variation in gallbladder disease.

CONCLUSIONS

These data suggest that genetic factors are responsible for at least 30% of symptomatic gallstone disease. However, the true role of heredity in gallstone pathogenesis is probably higher because data based on symptomatic gallbladder disease underestimates the true prevalence in the population.

Gallstone disease prevalence in Western Siberia: cross-sectional ultrasound study versus autopsy

BACKGROUND

The aims of this study were: (i) to evaluate the prevalence of gallstones in a Western Siberian urban population; and (ii) to compare the results of ultrasonographic screening of the living population with hospital autopsy data.

METHODS

A representative sample of 842 men and 870 women (aged 25-64 years) living in Novosibirsk, Western Siberia, was screened for the presence of gallstones by gallbladder ultrasonography. Participants were considered to have gallstone disease if they had already had cholecystectomy or if gallstones were revealed during the survey. Hospital autopsy data (n = 1124) were reviewed retrospectively for the 8-year period in the same region.

RESULTS

The prevalence of gallstone disease was significantly higher in women than in men and increased with age. Age-adjusted prevalence rates of gallstone disease for the 25-64-year age group were 1.9% in men and 9.5% in women in a cross-sectional ultrasonographic study. Corresponding values in the autopsy series were 2.2% in men and 11.2% in women.

CONCLUSIONS

The present report shows that the prevalence of gallstone disease in the female population is in the range of that reported from Western countries, whereas that in the male population is lower than that in other countries. The results of the ultrasonographic survey of the living population and of hospital autopsy data were comparable, with slightly higher gallstone detection rates in the autopsy study.

Pancreatic and biliary disorders in the elderly

Structural and functional changes in the biliary tract and pancreas associated with advanced age are well documented in the literature and must be taken into account in evaluating patients with possible biliary and pancreatic disorders. The relationship between normal, age-related physiologic changes and various pancreatico-biliary diseases is not well defined. Elderly patients may present with severe biliary and pancreatic disease that may pose difficult management problems because of coexisting medical illnesses. Despite these challenges, all but the most frail elderly patients can benefit from appropriate medical, endoscopic, and surgical therapy.

Prevalence of gallstone disease in Iran

BACKGROUND

Prevalence of gallstone disease is different depending on the geographic region involved. Few studies, in Asia but not from Iran, about the frequency of gallstone disease have been published. The aim of this study is to examine the prevalence of gallstone disease in Iran.

METHODS

Four hundred and seventy-seven nomads from southern Iran, 513 industrial laborers older than 34 years, and 421 laborers from a pharmaceutical company above 30 years of age, and 471 elderly persons from three nursing homes near Tehran underwent abdominal sonography.

RESULTS

There were 1373 men and 509 women. Eighty-nine subjects had gallstone disease and 10.1% of them were cholecystectomized. While the prevalence in the men and women in the age group 31-40 years was very low (0.3% in men and 1.8% in women), it increases sharply in men older than 60 years and women older than 50 years to more than 10-fold (12.5 and 24.6% in male and female with an age 71-80 years, respectively).

CONCLUSION

In Iran, gallstone disease is very uncommon in middle-aged people, but increases sharply in older people. However, this does not reach the high prevalence seen in Western countries. The intake of a high fiber-containing diet, a low number of overweight people, smoking habit and hyperlipidemia are probably the cause for this low prevalence.

Quantitative trait loci mapping for cholesterol gallstones in AKR/J and C57L/J strains of mice

Quantitative trait locus (QTL) mapping was used to locate genes that determine the difference in cholesterol gallstone disease between the gallstone-susceptible strain C57L/J and the gallstone-resistant strain AKR/J. Gallstone weight was determined in 231 male (AKR x C57L) F(1) x AKR backcross mice fed a lithogenic diet containing 1% cholesterol, 0.5% cholic acid, and 15% butterfat for 8 wk. Mice having no stones and mice having the largest stones were genotyped at approximately 20-cM intervals to find the loci determining cholesterol gallstone formation. The major locus, Lith1, mapped near D2Mit56 and was confirmed by constructing a congenic strain, AK. L-Lith1(s). Another locus, Lith2, mapped near D19Mit58 and was also confirmed by constructing a congenic strain AK.L-Lith2(s). Other suggestive, but not statistically significant, loci mapped to chromosomes 6, 7, 8, 10, and X. The identification of these Lith genes will elucidate the pathophysiology of cholesterol gallstone formation.

The prevalence and natural history of gallstones in spinal cord injured patients

BACKGROUND

Individuals with a spinal cord injury are at increased risk for the development of gallstones. Because these patients cannot reliably manifest classic symptoms of biliary colic, they may be more likely to present with advanced biliary complications than patients with intact abdominal innervation. The natural history of gallstones in spinal cord injured patients has not been described.

STUDY DESIGN

All spinal cord injured patients seen at the Seattle Veterans Affairs Medical Center from January 1, 1993, to December 31, 1997 were included in the study. For each patient, the presence or absence of gallstones had been determined previously through screening abdominal ultrasonographic evaluations. Pertinent demographic information was obtained from medical records and patient interviews. Patients with gallstones were followed until death, cholecystectomy, or the conclusion of the study, and the annual incidence of biliary complications and patients requiring a cholecystectomy were determined. The prevalence of gallstones was established by studying the subset of patients seen at the Seattle Spinal Cord Injury Unit from January 1, 1995 to December 31, 1997.

RESULTS

Among the spinal cord injured patients, 31% either had gallstones or had undergone a cholecystectomy at some point after their injury. Increasing age, female gender, and greater severity of injury were risk factors for the formation of gallstones. Over the first 5 years after the diagnosis of gallstones, the annual incidence of cholecystectomy or biliary complications was 6.3% and 2.2%, respectively.

CONCLUSIONS

Spinal cord injured patients are at increased risk for the development of gallstones. Patients with gallstones are at an increased risk for the development of biliary complications compared with neurologically intact patients, but the magnitude of this risk does not warrant prophylactic cholecystectomy.