Lack of correlation between serum lipoproteins and biliary cholesterol saturation in patients with gallstones

The prevalence and risk factors for gallstone disease in taiwanese vegetarians

Introduction

Gallstone disease (GSD) and its complications are major public health issues globally. Although many community-based studies had addressed the risk factors for GSD, little is known about GSD prevalence and risk factors among Taiwanese vegetarians.

Methods

This study included 1721 vegetarians who completed a questionnaire detailing their demographics, medical history, and life-styles. GSD was ascertained by ultrasonography or surgical history of cholecystectomy for GSD. The predictive probability of GSD for male and female vegetarians was estimated from the fitted model.

Results

The prevalence of GSD was 8.2% for both male and female vegetarians. The risk of GSD is similar in men and women across all age groups, and increases steadily with increasing age. For male vegetarians, age (OR: 1.04; 95% CI: 1.00–1.08) and serum total bilirubin level (OR: 2.35; 95% CI: 1.31–4.22) predict risk for GSD. For female vegetarians, age (OR: 1.03; 95% CI: 1.01–1.05), BMI (OR: 1.07; 95% CI: 1.01–1.13), and alcohol consumption (OR: 7.85; 95% CI: 1.83–33.73) are associated with GSD. GSD is not associated with type of vegetarian diet, duration of vegetarianism, low education level, physical inactivity, diabetes, coronary artery disease, cerebral vascular accident, chronic renal failure, hepatitis C virus infection, and lipid abnormalities. GSD is also not associated with age at menarche, postmenopausal status, and multiparity in female vegetarians.

Conclusions

Risk factors useful for predicting GSD in vegetarians are (1) age and total bilirubin level in men, and (2) age, BMI, and alcohol consumption in women. Many previously identified risk factors for general population does not seem to apply to Taiwanese vegetarians.

Gallstones are Associated with Intima-Media Thickness of Common Carotid Arteries in Men

Background

The prevalence of gallstone disease is increasing in Korea. Gallstone disease and atherosclerosis share common risk factors. Ultrasonographic carotid intima-media thickness is an independent predictor of atherosclerosis. We measured the carotid intima-media thickness among men who had gallstones to establish the association between atherosclerosis and gallstones.

Methods

A total of 330 men who visited the health promotion center of the IS Hallym Hospital from January 2011 to July 2012 were recruited. Both abdomen and carotid ultrasonographies were performed. Demographic, anthropometric, and biochemical data were collected.

Results

The prevalence of gallstones was 6.6%. The carotid intima-media thickness, age, and body mass index were higher in subjects with gallstones (P < 0.05 for all). After Pearson correlation analysis, gallstone, age, body mass index, and fasting blood sugar were significantly associated with carotid intima-media thickness. A statistically positive association between gallstone and carotid intima-media thickness was demonstrated in a multivariate analysis adjusted for age, body mass index, and fasting blood sugar.

Conclusion

Carotid intima-media thickness is higher in male subjects with gallstones, indicating that they are at greater risk for atherosclerosis.

The aetiology of symptomatic gallstones quantification of the effects of obesity, alcohol and serum lipids on risk. Epidemiological and biomarker data from a UK prospective cohort study (EPIC-Norfolk)

OBJECTIVE

The development of gallstones is influenced by obesity and alcohol. This study aimed to precisely quantify these risks and investigate whether the aetiological mechanism may involve serum lipids, for the first time using a European prospective cohort study.

METHODS

The European Prospective Investigation into Cancer-Norfolk, recruited 25 639 men and women, aged 40 to 74 years, between 1993 and 1997. At enrolment weight, height and alcohol intake were recorded and nonfasting blood samples taken to measure serum triglycerides, cholesterol, high-density lipoproteins and low-density lipoproteins. The cohort was monitored for 14 years for symptomatic gallstones. Cox regression estimated sex-specific hazard ratios (HRs) for symptomatic gallstones adjusted for covariates.

RESULTS

Symptomatic gallstones developed in 296 people (67.9% women). For each additional unit of BMI, the HR in men was 1.08 [95% confidence interval (CI)=1.02-1.14]; in women the HR was 1.08 (95% CI=1.06-1.11). Every unit of alcohol consumed per week decreased risk in men by 3% (HR=0.97, 95% CI=0.95-0.99) with no effect in women. Serum triglycerides increased risk in men (highest vs. lowest quarter HR=2.02, 95% CI=1.03-3.98) and women (HR=2.43, 95% CI=1.52-3.90). Increased high-density lipoprotein was associated with a decreased risk in men (highest vs. lowest quarter HR=0.22, 95% CI=0.09-0.52) and women (HR=0.55, 95% CI=0.36-0.85). No effects were found for serum cholesterol and low-density lipoprotein.

CONCLUSION

Obesity and alcohol influence gallstone formation, possibly in part through their effects on serum lipids. Reducing obesity may prevent gallstones in the population, as 38% of incident cases of gallstones were associated with a BMI of more than 25.

Diabetes and hyperlipidemia correlate with gallbladder contractility in leptin-related murine obesity

Obesity is associated with many comorbid conditions including diabetes, hyperlipidemia, and gallstones. However, the interaction among these modalities remains unclear. We recently demonstrated that both leptin-deficient and leptin-resistant obese mice have impaired biliary motility. These obese mice also are diabetic and hyperlipidemic. Therefore, we tested the hypothesis that serum glucose, insulin, cholesterol, and triglyceride levels would correlate with gallbladder contractility. Thirty-four lean control, 10 lean heterozygous leptin-deficient, 18 obese homozygous leptin-deficient, and 12 obese homozygous leptin-resistant mice were fed a nonlithogenic chow diet while nine lean control and nine obese homozygous leptin-deficient mice were fed a high-cholesterol diet for 4 weeks. In vitro gallbladder responses to cholecystokinin (CCK; 10(-8) mol/L), acetylcholine (ACh; 10(-5) mol/L), and neuropeptide Y (NPY; 10(-6) mol/L) were measured. Serum glucose, insulin, cholesterol, and triglyceride levels were measured from pooled serum from an additional 704 animals. Gallbladder responses were greatest for CCK, intermediate for ACh, and least for NPY. Serum glucose, insulin, cholesterol, and triglyceride levels and body weight all correlated similarly, negatively, and significantly (P<0.001) with gallbladder contractility. Hyperglycemia, insulin-resistance, hyperlipidemia, and body weight in obese mice with leptin dysfunction are associated with poor gallbladder contractility, which in turn may contribute to the association between obesity and gallstone formation.

The relation between biliary lipids, nucleation time, and number of gallbladder stones after percutaneous gallbladder puncture

BACKGROUND

Biliary lipids and nucleation time are increasingly of importance in the understanding of the cholesterol nucleation process in gallstone patients.

METHODS

Biliary lipids, total lipid concentration (TLC), cholesterol saturation index (CSI) and nucleation time (NT) were studied in 221 bile samples from patients with solitary (n = 120) and multiple (n = 101) gallbladder stones.

RESULTS

Biliary cholesterol concentration and CSI did not differ between patients with solitary or multiple stones; however, it was positively correlated with the CSI (r = 0.93; p < 0.01). We found a negative correlation between CSI and TLC (r = -0.77 for solitary stones and r = -0.79 for multiple stones; p < 0.01). Furthermore, levels of total bile acids and phospholipids were similar in cases with solitary and multiple gallbladder stones. TLC did not correlate with single or multiple stones, whereas NT was determined to be negatively correlated with the number of gallstones (r = -0.39; p < 0.01). Patients with solitary stones had a significantly (p < 0.01) longer NT than those with multiple gallbladder stones (7.5 +/- 4.2 days versus 2.3 +/- 1.5 days).

CONCLUSIONS

Our findings suggest that there exists a nucleation-promoting activity, which seems to be more pronounced in patients with multiple gallbladder stones than in those with solitary stones, indicating a major risk factor for the higher recurrence rate seen in these patients.

Disorders of bile acid metabolism in cholesterol gallstone disease

The aim of the study was to evaluate the metabolism of individual bile acids in patients with cholesterol gallstone disease. Therefore, we determined pool size and turnover of deoxycholic (DCA), cholic (CA), and chenodeoxycholic acid (CDCA) in 23 female gallstone patients classified according to their gallbladder function and in 15 healthy female controls. Gallstone patients had normal hepatic bile acid synthesis, but, depending on gallbladder function, differed with respect to turnover and size of the bile acid pools: Patients with well-emptying gallbladder (group A, n = 9) had enhanced turnover and reduced pools of CA (-46%; P less than 0.01 vs. controls) and CDCA (-24%; P less than 0.05), but normal input and size of the DCA pool. With reduced gallbladder emptying (less than 50% of volume; group B, n = 6), turnover and pools of CA, CDCA, and DCA were similar as in controls. Patients with loss of gallbladder reservoir (group C, n = 8) had increased input (+100%; P less than 0.01) and pool size of DCA (+45%; P = 0.07) caused by rapid conversion of CA to DCA, while the pools of CA (-71%; P less than 0.001 vs. controls) and CDCA (-36%; P less than 0.05) were reduced by enhanced turnover. Thus, in patients with cholesterol gallstones, the pools of primary bile acids are diminished, unless gallbladder emptying is reduced. Furthermore, in a subgroup of gallstone patients, who had completely lost gallbladder function, the CA pool is largely replaced by DCA owing to rapid transfer of CA to the DCA pool. This probably contributes to supersaturation of bile with cholesterol.

Plasma HDL cholesterol concentrations are correlated to bile cholesterol saturation index in the African green monkey

In an attempt to determine if plasma lipoprotein concentrations correlate with the bile cholesterol saturation index in the African green monkey, we have studied a group of adult male animals available from a long-term study investigating the effects of dietary fat and cholesterol on cholesterol metabolism and atherosclerosis. The animals were fed diets containing 0.8 mg cholesterol/kcal or 0.03 mg cholesterol/kcal for five years. Within each dietary cholesterol group, animals received 42% of dietary calories as fat, enriched with either saturated or polyunsaturated fat. Using stepwise multiple linear regression, high density lipoprotein (HDL) cholesterol concentration was found to be the best plasma lipid predictor of the bile cholesterol saturation index. When the cholesterol saturation index of a fasting gallbladder bile specimen was compared to the plasma HDL cholesterol level for individual animals, a significant positive correlation was noted for animals fed polyunsaturated fat, (r = 0.68) and for animals fed saturated fat (r = 0.72). For any value of HDL cholesterol, however, the cholesterol saturation index was higher in animals fed polyunsaturated fat compared to saturated fat. Since plasma HDL cholesterol levels were positively correlated with the bile cholesterol saturation index in adult male African green monkeys, we conclude that a metabolic link exists between plasma HDL cholesterol concentrations and bile cholesterol saturation, perhaps due to enhanced delivery of cholesterol to the liver by HDL.

Lipid metabolism in bile acid malabsorption

Malabsorption of bile acid increases cholesterol synthesis and activates hepatic LDL receptors which leads to enhanced elimination of cholesterol from the body. Interruption of enterohepatic circulation of bile acids may lead to a smaller bile acid pool, which, in turn, impairs cholesterol and fat absorption by reduced micellar solubilization. Together with reduced cholesterol absorption, the increased cholesterol loss as bile acids also reduces plasma cholesterol concentrations and the biliary cholesterol excretion, too. Diminished biliary cholesterol in bile acid malabsorption may contribute to the increased incidence of gallstones associated with ileal dysfunction. Malabsorption of bile acid leads to a fall in LDL-cholesterol concentration, and an increase of HDL-cholesterol concentration has been reported. VLDL-triglyceride concentrations are almost invariably raised. Enhanced cholesterol and bile acid synthesis in ileal dysfunction is reflected by raised concentrations of plasma cholesterol precursors, especially lathosterols, which can be used as an indicator of increased bile acid loss to faeces. Cholesterol absorption, in turn, correlates positively with plasma plant sterol concentrations levels and the ratio of lathosterols to campesterols can be used as a screening measurement for ileal dysfunction. Plasma fatty acid composition is also altered as a response to fat malabsorption associated with ileal dysfunction. The proportion of essential fatty acids is inversely correlated with faecal fat excretion and endogenous fatty acid synthesis is activated.

The epidemiology of gallstone disease in Rome, Italy. Part II. Factors associated with the disease. The Rome Group for Epidemiology and Prevention of Cholelithiasis (GREPCO)

The epidemiological associations of gallstone disease were evaluated in a population of 2,325 civil servants (1,244 men and 1,081 women) in Rome, Italy, which was enrolled in a cross-sectional survey on cholelithiasis. Participants were screened for the presence of gallstones by gallbladder ultrasonography, completed a questionnaire on family and personal history and underwent a physical examination and blood chemistry. Statistically significant associations were established by univariate analysis of the age-standardized data and by step-wise multiple logistic regression. At univariate analysis, increasing age, serum triglycerides and number of cigarettes smoked per day, and decreasing high-density lipoprotein-cholesterol were the conditions associated with the presence of gallstones in men. Age and parity were the correspondent associations in women. After controlling by multiple logistic regression, a different pattern of associated conditions emerged. In men, only age and serum triglycerides showed a significant positive association with gallstones, which was independent of other variables. In women, the presence of gallstones was independently associated with increasing age, number of pregnancies, body mass index and serum triglycerides, and with decreasing total (and low-density lipoprotein) cholesterol. The latter association was curvilinear in shape. The conditions associated with a history of cholecystectomy differed from those observed in subjects with gallstones, with the exceptions of age, in both sexes, and high serum triglycerides, in women. Fasting blood glucose levels were higher in women with a history of cholecystectomy than in those with or without gallstones, both at univariate and multiple logistic regression analyses.(ABSTRACT TRUNCATED AT 250 WORDS)

Cholesterol gallstone disease: the current status of nonsurgical therapy

Gallstone disease is a common disease that appears to be related to a Western diet. The underlying pathogenesis is a subtle alteration in the liver such that excessive cholesterol is extracted from the liver cell by bile acids undergoing an enterohepatic recirculation. Gallstone disease progresses through well-defined stages, beginning with a bile supersaturated with cholesterol and proceeding to crystal formation, stone growth, and finally symptoms caused by impaction of a stone in either the cystic duct or the common bile duct. The natural history is that most stones never cause symptoms. Stones that cause symptoms have been present for an average of 12 years. The treatment of truly asymptomatic stones should be observation. Ultrasonography of the right upper quadrant is the gold standard for the diagnosis of stones in the gallbladder. Endoscopic retrograde cholangiopancreatography (ERCP) is the gold standard for the diagnosis of stones in the common bile duct. Oral cholecystogram (OCG) helps select patients who have noncalcified, floating stones that may be dissolved with bile acids or methyl tertiary butyl ether (MTBE). Therapy with chenodiol has been a disappointment because of a low complete response rate. The ideal candidate for attempted dissolution with chenodiol would be a thin woman with hypercholesterolemia and a small number of symptomatic, small, floating, radiolucent gallstones. Ursodeoxycholic acid (Urso), when it is available, will have all of the attributes of chenodiol and virtually none of the side effects. Rapid dissolution of gallstones with MTBE shows great promise of being a generally available means of dissolving gallstones. Extracorporeal shock wave lithotripsy also shows promise, but its general availability may be limited by the cost of the equipment needed. As of now, the treatment of choice for symptomatic gallstones remains cholecystectomy, unless there is a compelling reason not to operate.