Apolipoprotein E genotype and gallbladder disease risk in a large population-based cohort

[New Progress in Longitudinal Research on the Risk Factors for Cholelithiasis]

Cholelithiasis is a common disease of the digestive system. The risk factors for cholelithiasis have been reported and summarized many times in the published literature, which primarily focused on cross-sectional studies. Due to the inherent limitations of the study design, the reported findings still need to be validated in additional longitudinal studies. Moreover, a number of new risk factors for cholelithiasis have been identified in recent years, such as bariatric surgery, hepatitis B virus infection, hepatitis C virus infection, kidney stones, colectomy, osteoporosis, etc. These new findings have not yet been included in published reviews. Herein, we reviewed the 101 cholelithiasis-associated risk factors identified through research based on longitudinal investigations, including cohort studies, randomized controlled trials, and nested case control studies. The risk factors associated with the pathogenesis of cholelithiasis were categorized as unmodifiable and modifiable factors. The unmodifiable factors consist of age, sex, race, and family history, while the modifiable factors include 37 biological environmental factors, 25 socioenvironmental factors, and 35 physiochemical environmental factors. This study provides thorough and comprehensive ideas for research concerning the pathogenesis of cholelithiasis, supplying the basis for identifying high-risk groups and formulating relevant prevention strategies.

The association between apolipoprotein E and gallstone disease: an updated meta-analysis

BACKGROUND

Gallstone disease (GSD) is a common biliary tract disease worldwide. Previous studies have investigated the association of apolipoprotein E (APOE) E4 with GSD and reported inconsistent results.

METHODS

In this paper, we conducted meta-analyses to examine whether APOE E4 is associated with the risk of GSD. A systematic literature search was performed in PubMed, Cochrane Library, EMBASE, and Google Scholar using the following inclusion criteria: 1) Studies on human subjects; 2) subjects in the control group must undergo ultrasound GSD screening, and presence of GSD in the experiment group can be clearly determined, e.g., diagnosis of GSD through ultrasound screening or a previous history of cholecystectomy or cholelithiasis; 3) the studies reported APOE genotype data (APOE E4+ vs. E4-) for subjects with and without GSD. In all the meta-analyses, we used random-effects models to calculate the odds ratios (ORs) as a measure of association as well as the corresponding confidence intervals (CIs).

RESULTS

Our literature search found 13 publications with 14 studies, including a total of 1632 GSD patients and 5001 controls, that met the eligibility criteria and were included in the meta-analyses. We did not find a significant association between APOE E4 and risk of GSD (OR = 1.23, 95% CI: 0.89-1.68; p = 0.205). No significant associations were observed in subgroup analyses by gender and mean age. We obtained similar insignificant findings if an additive model was used, if subjects who had E2E4 genotype were excluded, or if low-quality studies were excluded.

CONCLUSION

Our meta-analysis found insufficient evidence for the effect of APOE E4 on GSD risk. Future studies with large sample sizes that control for important confounding/risk factors are needed to validate our findings and to explore other genetic loci that might affect GSD risk.

Relationship of Gallbladder Diseases with Sociodemographic Characteristics, Lifestyle, and Chronic Diseases in Northeastern China

BACKGROUND

Gallbladder diseases are common in Jilin, China. However, there have been few previous studies on this disease. Our study used the chronic disease database in Jilin Province to study the factors correlated with gallbladder diseases.

METHODS

A total of 21,435 people were selected from the Jilin Province adult chronic disease survey conducted in 2012. Multistage stratified random cluster sampling was used in this cross-sectional study. Multiple logistic regression analysis was used to explore the independent associations of different factors with gallbladder diseases.

RESULTS

There were 1876 people with gallbladder diseases, and the prevalence of the diseases was 8.8% (males 4.4%, females 12.8%). Multivariate logistic regression analysis showed that female (prevalence odds ratio (POR) = 3.13, 95% confidence intervals (CIs): 2.76⁻3.55), older people (30⁻45 years (POR = 2.79, 95% CIs: 2.06⁻3.77), 45⁻60 years (POR = 4.26, 95% CIs: 3.17⁻5.73), 60⁻79 years (POR = 4.72, 95% CIs: 3.48⁻6.41)), people living in rural areas (POR = 1.65, 95% CIs: 1.49⁻1.82), smoking (current smoker (POR = 1.15, 95% CIs: 1.01⁻1.31), former smoker (POR = 1.37, 95% CIs: 1.13⁻1.66)), high frequency of eating seafood (POR = 0.77, 95% CIs: 0.63⁻0.93), and high frequency of eating soy products (POR = 0.50, 95% CIs: 0.44⁻0.58) were associated with gallbladder diseases.

CONCLUSIONS

We found that there were some factors associated with gallbladder disease, and there needs to be further studies to confirm these associations.

APOE and FABP2 Polymorphisms and History of Myocardial Infarction, Stroke, Diabetes, and Gallbladder Disease

Dysfunctional lipid metabolism plays a central role in pathogenesis of major chronic diseases, and genetic factors are important determinants of individual lipid profiles. We analyzed the associations of two well-established functional polymorphisms (FABP2 A54T and APOE isoforms) with past and family histories of 1492 population samples. FABP2-T54 allele was associated with an increased risk of past history of myocardial infarction (odds ratio (OR) = 1.51). Likewise, the subjects with APOE4, compared with E2 and E3, had a significantly increased risk of past history myocardial infarction (OR = 1.89). The OR associated with APOE4 was specifically increased in women for past history of myocardial infarction but decreased for gallstone disease. Interactions between gender and APOE isoforms were also significant or marginally significant for these two conditions. FABP2-T54 allele may be a potential genetic marker for myocardial infarction, and APOE4 may exert sex-dependent effects on myocardial infarction and gallbladder disease.

Genetic determinants of serum lipid levels in Chinese subjects: a population-based study in Shanghai, China

We examined the associations between 21 single nucleotide polymorphisms (SNPs) of eight lipid metabolism genes and lipid levels in a Chinese population. This study was conducted as part of a population-based study in China with 799 randomly selected healthy residents who provided fasting blood and an in-person interview. Associations between variants and mean lipid levels were examined using a test of trend and least squares mean test in a general linear model. Four SNPs were associated with lipid levels: LDLR rs1003723 was associated with total cholesterol (P-trend = 0.002) and LDL (P-trend = 0.01), LDLR rs6413503 was associated with total cholesterol (P-trend = 0.05), APOB rs1367117 was associated with apoB (P-trend = 0.02), and ABCB11 rs49550 was associated with total cholesterol (P-trend = 0.01), triglycerides (P-trend = 0.01), and apoA (P-trend = 0.01). We found statistically significant effects on lipid levels for LDLR rs6413503 among those with high dairy intake, LPL rs263 among those with high allium vegetable intake, and APOE rs440446 among those with high red meat intake. We identified new associations between SNPs and lipid levels in Chinese previously found in Caucasians. These findings provide insight into the role of lipid metabolism genes, as well as the mechanisms by which these genes may be linked with disease.

Apolipoprotein E/C1 locus variants modify renal cell carcinoma risk

Lipid peroxidation is considered a unifying mechanistic pathway through which known risk factors induce renal cell carcinoma (RCC). We hypothesized that genes selected a priori for their role in lipid peroxidation would modify cancer risk. We genotyped 635 single nucleotide polymorphisms (SNP) in 38candidate genes in 777 Caucasian RCC cases and 1,035 controls enrolled in a large European case-control study. Top candidate SNPs were confirmed among 718 Caucasian cases and 615 controls in a second study in the United States. Two of the three SNPs (rs8106822 and rs405509) that replicated in the U.S. study were within a regulatory region of the APOE promoter. The OR for rs8106822 A>G variant was 1.22(AG) and 1.41(GG) (P(trend) = 0.01) in the European study, 1.05(AG) and 1.51(GG) (P(trend) = 0.03) in the U.S. study, and 1.15(AG) and 1.44(GG) (P(trend) = 0.001) among 1,485 cases and 1,639 controls combined. The rs405509 G>T variant was associated with risk in the European (OR, 0.87(TG); OR, 0.71(TT); P(trend) = 0.02), the U.S. (OR, 0.68(TG); OR, 0.71(TT); P(trend) = 0.02), and both studies combined (OR(TG), 0.79; OR(TT), 0.71; P(trend) = 0.001), as was the G-G haplotype (r(2) = 0.64; P= 4.7 x 10(-4)). This association is biologically plausible as SNP rs405509 was shown to modify protein binding and transcriptional activity of the APOE protein in vitro and is in linkage disequilibrium with key known variants defining the e2, e3, and e4 alleles that modify risk of atherosclerosis, Alzheimer's disease risk, and progression to AIDS. In two large case-control studies, our findings further define a functional region of interest at the APOE locus that increases RCC susceptibility.

Association of central obesity with the severity and audiometric configurations of age-related hearing impairment

To investigate the effect of central obesity on the severity and characteristics of age-related hearing impairment (ARHI), we recruited 690 adult subjects with normal or symmetrical sensorineural hearing loss (SNHL). The effects of age, gender, morphometry, habits, systemic diseases, and environmental noise exposure on average pure tone hearing level at low frequencies (pure tone audiometry (PTA)-low) and high frequencies (PTA-high) were analyzed. After adjusting for age, gender, systemic disease, and other variables, waist circumference (WC) showed a significant positive association with PTA-low and PTA-high. In females, PTA-low and PTA-high only showed significant positive association with age, but not with WC or other variables. However, PTA-high showed a positive association with borderline significance with WC in female subjects older than 55. In males, WC as well as age and noise exposure showed significant positive associations with both PTA-low and PTA-high, primarily in subjects younger than 55. When both WC and BMI were taken into account in a backward stepwise multivariate linear regression analysis, WC, but not BMI, showed a significant positive association with PTA-low and PTA-high in males younger than 55, and with PTA-high with borderline significance in females older than 55. However, the audiogram patterns were not significantly affected by central obesity in either age or gender. Our results suggest that WC was, even after adjustment for BMI, an independent risk factor of ARHI, particularly for low and high frequencies in males younger than 55 and for high frequencies in female subjects older than 55.

Polymorphisms of genes in the lipid metabolism pathway and risk of biliary tract cancers and stones: a population-based case-control study in Shanghai, China

Biliary tract cancers, encompassing the gallbladder, extrahepatic bile duct, and ampulla of Vater, are uncommon yet highly fatal malignancies. Gallstones, the primary risk factor for biliary cancers, are linked with hyperlipidemia. We examined the associations of 12 single nucleotide polymorphisms of five genes in the lipid metabolism pathway with the risks of biliary cancers and stones in a population-based case-control study in Shanghai, China. We included 235 gallbladder, 125 extrahepatic bile duct, and 46 ampulla of Vater cancer cases, 880 biliary stone cases, and 779 population controls. Subjects completed an in-person interview and gave blood. Genotyping was conducted by TaqMan assay using DNA from buffy coats. The effects of APOE IVS1+69 (rs440446) and APOB IVS6+360C>T (rs520354) markers were limited to men. Men carrying the G allele of APOE IVS1+69 had a 1.7-fold risk of stones [95% confidence interval (95% CI), 1.2-2.4], a 1.8-fold risk of gallbladder cancer (95% CI, 1.0-3.3), a 3.7-fold risk of bile duct cancer (95% CI, 2.0-7.0), and a 4-fold risk of ampullary cancer (95% CI, 1.4-12.4). Male carriers of the T allele of APOB IVS6+360C>T had a 2-fold risk of bile duct cancer (95% CI, 1.2-3.4). The APOB T-T haplotype (APOB IVS6+360C>T, EX4+56C>T) was associated with a 1.6-fold risk of bile duct cancer (95% CI, 1.1-2.3). Male and female carriers of the T allele of LDLR IVS9-30C>T (rs1003723) had a 1.5-fold risk of bile duct cancer. Our findings suggest that gene variants in the lipid metabolism pathway contribute to the risk of biliary tract stones and cancers, particularly of the bile duct.