Genetic variants of glutathione S-transferase as possible risk factors for hepatocellular carcinoma: a HuGE systematic review and meta-analysis

The authors performed a systematic review and meta-analysis to determine the effect of polymorphisms in genes encoding glutathione S-transferases (GSTs), phase II isoenzymes involved in cellular detoxification, on risk of hepatocellular carcinoma (HCC). Fifteen eligible studies were identified: 14 evaluated GSTM1; 13, GSTT1; three, GSTP1; and one each evaluated GSTM2, GSTM3, GSTA1, GSTA4, GSTO1, and GSTO2, respectively. All were case-control studies performed in populations with high (Asian, African) and medium (European) HCC incidence rates. Random-effects meta-analyses suggested a small excess risk of HCC with GSTT1 null (odds ratio (OR) = 1.19, 95% confidence interval (CI): 0.99, 1.44) and possibly GSTM1 null (OR = 1.16, 95% CI: 0.89, 1.53) genotypes. Cumulative meta-analyses demonstrated that both pooled estimators generally trended toward a small excess risk with publication of more recent studies. Results for GSTP1 A313G suggested no excess risk (OR = 0.75, 95% CI: 0.50, 1.15). A number of potentially interesting gene-gene and gene-environment interactions were reported, but these were too few and inconsistent to allow meta-analysis. The overall results suggest that there may be a small excess risk of HCC in individuals with GSTT1 null and possibly also with GSTM1 null genotypes. However, given the relatively limited total number of subjects examined and observed between-study heterogeneity, chance could not be excluded.     

Nuts and legumes consumption and risk of colorectal cancer: a systematic review and meta-analysis

European Journal of Epidemiology - Several case–control and prospective cohort studies have examined the association between the consumption of nuts and legumes and the risk of colorectal...     

Systematic review and meta-analysis of soy products consumption in patients with type 2 diabetes mellitus

Clinical trials have reported the lipid-lowering effect of consuming soy products, and epidemiological studies have shown that soy intake is associated with decreased risk of type 2 diabetes mellitus (T2DM). The aim of this meta-analysis was to systematically review the effects of soy products consumption on serum lipid profiles and glycaemic control in T2DM patients. Potential papers were initially searched from PubMed (1966 to 2010) and Cochrane Library (1984 to 2010) without language limitations. All randomized controlled trials were included in which soy products supplementation was the only intervention in subjects with type 2 diabetes. Weighted mean effect size was calculated for net changes in serum lipids and fasting glucose concentrations using fixed-effect or random-effect models. Previously defined subgroup analyses were performed to identify the source of heterogeneity. Eight studies were included according to the criteria. The intake of soy products was associated with a significant reduction in serum total cholesterol (by 0.42 mmol/L; 95% confidence interval (CI): -0.70, -0.14; p<0.001), triacylglycerol (by 0.22 mmol/L; 95% CI: -0.38, -0.07; p<0.001) and low-density lipoprotein-cholesterol (by 0.30 mmol/L; 95% CI: -0.60, -0.00; p<0.001), and a significant increase in high-density lipoprotein-cholesterol (0.05 mmol/L; 95% CI: 0.04, 0.06; p=0.89). There were no significant effects on fasting glucose, insulin and glycated hemoglobin. It can be concluded that intake of soy and soy products has beneficial effects in T2DM patients in relation to serum lipids.     

Two-dose schedules for human papillomavirus vaccine: Systematic review and meta-analysis

Simpler schedules for human papillomavirus (HPV) vaccine delivery could improve vaccine coverage and the effectiveness of cervical cancer prevention. The objective of this study was to systematically review evidence about the effects of two-dose compared with three-dose schedules for human papillomavirus (HPV) vaccine and to describe the uptake of two-dose HPV vaccination schedules globally. We searched PubMed, the Cochrane Central Registry of Controlled Trials, trials registers, and manufacturers’ databases from their earliest date to February 2016. We selected randomised controlled trials and controlled clinical trials that directly compared HPV vaccine schedules with two or three doses. We extracted data on immunological and clinical outcomes and used meta-analysis where appropriate. We also described the use of two-dose HPV vaccine schedules globally. We screened 1464 items and included seven eligible noninferiority trials in 11 countries. In randomised comparisons amongst adolescent girls (three trials), geometric mean concentrations (GMC) of antibodies against HPV16 and HPV18 were non-inferior or inconclusive, up to 24 months after a two-dose compared with a three-dose schedule. One trial with a clinical outcome found no persistent HPV infections occurred after either two or three doses. In non-randomised comparisons, GMC were non-inferior or superior in adolescent girls receiving the two-dose schedule compared with women receiving the three-dose schedule for at least 21 months after vaccination. By February 2017, 23 low and middle income and 25 high income countries had adopted a two-dose HPV vaccination schedule. A two-dose HPV vaccine schedule provides satisfactory immunological outcomes in adolescent girls, but uptake globally is limited, particularly in countries with the highest burden of cervical cancer.     

Alcohol consumption and the risk of endometrial cancer: a meta-analysis

Epidemiologic findings are inconsistent concerning the association of endometrial cancer risk with alcohol consumption. Therefore, we conduct a meta-analysis of studies that assessed the association of alcohol consumption and the risk of endometrial cancer. A systematic literature search up to April 2010 was performed in MEDLINE and EMBASE, and study-specific risk estimates were pooled using a random-effects model. In the present study, six prospective and 14 case-control studies were included. Alcohol intake was not significantly associated with the risk of endometrial cancer among prospective studies (relative risk (RR): 1.04; 95% confidence interval (CI): 0.91-1.18) or among case-control studies (odds ratio (OR): 0.89; 95% CI: 0.76-1.05). However evidence from the results of our stratified analyses revealed that increased risk of endometrial cancer was associated with liquor consumption (RR: 1.22; 95% CI: 1.03-1.45) but null association with wine and beer consumption. In conclusion, alcohol consumption is not associated with the risk of endometrial cancer. Future studies should also examine whether the relation varies according to different type of alcoholic beverages.     

Influence of dairy product and milk fat consumption on cardiovascular disease risk: a review of the evidence

Although evidence has linked the consumption of saturated fat (SF) to increased LDL levels and an increased risk of the development of cardiovascular disease (CVD), recent findings have indicated that the link between CVD and SF may be less straightforward than originally thought. This may be due to the fact that some food sources high in SF contain an array of saturated and unsaturated fatty acids, each of which may differentially affect lipoprotein metabolism, as well as contribute significant amounts of other nutrients, which may alter CVD risk. The purpose of this review is to examine the published research on the relationship between milk fat containing dairy foods and cardiovascular health. The findings indicate that the majority of observational studies have failed to find an association between the intake of dairy products and increased risk of CVD, coronary heart disease, and stroke, regardless of milk fat levels. Results from short-term intervention studies on CVD biomarkers have indicated that a diet higher in SF from whole milk and butter increases LDL cholesterol when substituted for carbohydrates or unsaturated fatty acids; however, they may also increase HDL and therefore might not affect or even lower the total cholesterol:HDL cholesterol ratio. The results from the review also indicate that cheese intake lowers LDL cholesterol compared with butter of equal milk fat content. In addition, the review highlights some significant gaps in the research surrounding the effects of full-fat dairy on CVD outcomes, pointing to the need for long-term intervention studies.     

Influenza vaccination for HIV-positive people: Systematic review and network meta-analysis

BackgroundPeople with Human Immunodeficiency Virus (HIV) are highly susceptible to influenza-related morbidity and mortality. In order to assess comparative efficacy of influenza vaccine strategies among HIV-positive people, we performed a systematic review and Bayesian network meta-analysis (NMA).MethodsIn this systematic review, we searched MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and CINAHL between 1946 and July 2015 for randomized controlled trials (RCTs) on influenza vaccines for HIV-positive adults reporting seroconversion or seroprotection outcomes. The NMAs were conducted within a Bayesian framework and logistic models were used for comparing the effect of the vaccine strategies on the two outcomes.ResultsA total of 1957 publications were identified, 143 were selected for full review, and 13 RCTs were included in our final analysis. Fourteen separate NMAs were conducted by outcomes, vaccine strain, and different outcome measurement timepoints. For example, compared with the 15 μg single vaccine strategy, the odds ratio was the highest for the adjuvant 7.5 μg booster strategy (2.99 [95% credible interval 1.18–7.66]) when comparing seroconversion for H1N1 at 14–41 days after the last dose of vaccination and for the 60 μg single strategy (2.33 [1.31–4.18]) when comparing seroconversion for strain B.ConclusionsThe adjuvant 7.5 μg booster and 60 μg single vaccine strategies provided better seroconversion and seroprotection outcomes. These findings have important implications for national and international guidelines for influenza vaccination for HIV-positive people and future research.     

螺杆菌感染与肝癌发生发展关系的Meta分析

目的通过Meta分析的方法探讨螺杆菌感染与肝癌发生发展的相关性。方法检索Medline、EMBASE、CNKI、万方和维普数据库中探讨螺杆菌感染与肝癌关系的研究,提取数据计算合并比值比(OR)以及95%置信区间(95%CI)。结果符合纳入排除标准的研究共有19项,均为病例对照研究,其中肝癌组785例,螺杆菌的感染率为66.50%(522/785),对照组1 298例,螺杆菌的感染率为37.75%(490/1 298)。各项研究之间具有明显异质性,选取随机效应模型进行分析,OR值为9.55(95%CI:5.78～15.77,P<0.05)。结论螺杆菌参与肝细胞癌的发生发展,但结果仍需进一步证实。     

Systematic review and meta-analysis of the association between complement component 3 and age-related macular degeneration: a HuGE review and meta-analysis

The authors performed a meta-analysis to estimate the magnitude of polymorphism effects for the complement component C3 gene (C3) and their possible mode of action on age-related macular degeneration (AMD). The meta-analysis included 16 and 7 studies for rs2230199 and rs1047286, respectively. Data extraction and risk of bias assessments were performed in duplicate, and heterogeneity and publication bias were explored. There was moderate evidence for association between both polymorphisms and AMD in Caucasians. For rs2230199, patients with CG and GG genotypes were 1.44 (95% confidence interval (CI): 1.33, 1.56) and 1.88 (95% CI: 1.59, 2.23) times more likely to have AMD than patients with the CC genotype. For rs1047286, GA and AA genotypes had 1.27 (95% CI: 1.15, 1.41) and 1.70 (95% CI: 1.27, 2.11) times higher risk of AMD than did GG genotypes. These gene effects suggested an additive model. The population attributable risks for the GG/GC and AA/GA genotypes are approximately 5%-10%. Subgroup analysis by ethnicity indicates that these variants are very infrequent in Asians and that the observed gene effects are based largely on the high frequency within Caucasian populations. This meta-analysis supports the association between C3 and AMD and provides a robust estimate of the genetic risk.     

A strong negative association between alcohol consumption and the risk of hepatocellular carcinoma in cirrhotic patients

We carried out a hospital-based, case-control study to assess the association of both the Hepatitis B Virus (HBV) infection and the lifetime daily alcohol intake with the risk of developing hepatocellular carcinoma (HCC) in patients with liver cirrhosis (LC). Cases were 62 consecutive inpatients of a Gastroenterology Division in whom a first diagnosis of HCC superimposed on LC was made. Two control groups were used: 310 patients without liver disease, matched 1:5 with cases and randomly selected from inpatients of the same hospital, and 97 consecutive asymptomatic inpatients in whom the first diagnosis of LC was made. Alcohol intake was quantified in all subjects by a standardized questionnaire. HBV infection was associated with HCC development in cirrhotics (odds ratio =6.8; 95% confidence interval =1.4–32.3), whereas we observed a trend towards a decreased HCC risk at increased alcohol intake values (odds ratio from 1 for lifetime abstainers to 0.2 for drinkers of 175 g/day or more). Our results suggest that alcohol intake is not a direct determinant of HCC, but its role is mediated by LC. Cirrhotics with high alcohol intake do not usually survive long enough to develop HCC.     

Vitamin D and cardiovascular disease: Systematic review and meta-analysis of prospective studies

BackgroundLow serum 25-hydroxyvitamin D (25-OH-D) has recently been linked to cardiovascular diseases. This review summarizes evidence from prospective studies evaluating the prognostic value of 25-OH-D for cardiovascular disease incidence and mortality.MethodA systematic literature search in EMBASE and Pubmed-Medline databases was performed until November 2009. Prospective studies published in English were selected reporting estimates for the association of 25-OH-D with primary or secondary cardiovascular event incidence or mortality in the general population or subjects with prevalent cardiovascular disease. Pooled risk estimators were derived by meta-analysis using a random effects model approach.ResultsFour incidence and five independent mortality studies were included. Two incidence and three mortality studies reported a two- to five-fold risk increase for both outcomes in subjects with lower 25-OH-D, while the others did not detect a significant association. Meta-analysis supported the existence of an inverse association.ConclusionData from prospective investigations suggest an inverse association between 25-OH-D and cardiovascular risk. However, given the heterogeneity and small number of longitudinal studies, more research is needed to corroborate a potential prognostic value of 25-OH-D for cardiovascular disease incidence and mortality.