Barrett's esophagus and its association with hiatal hernia, cigarette smoking and colonic tumors

Introduction and Aims Barrett's esophagus (BE) is a premalignant condition to esophageal adenocarcinoma involving metaplasia of the esophageal epithelium. Since BE was first identified and described, it has been closely associated with hiatal hernia. The strength of the relationship has never been quantified, nor has the association, adjusted for confounders such as obesity and reflux, been examined. Male gender, obesity and reflux are well recognized risk factors for BE, however it is less certain what role environmental factors such as cigarette smoking play in the development of the condition. The association of BE with colonic tumors has also been speculated on but not clearly established. The aim of this thesis was to further explore the epidemiology of BE, specifically the relationship between BE and hiatal hernia, cigarette smoking and colonic tumors, through meta-analyses. Methods Three meta-analyses and systematic reviews were conducted, quantifying the relationship between BE and hiatal hernia, cigarette smoking and colonic tumors, respectively. Four electronic databases (Medline, PubMed, Embase, and Current Contents Connect) were searched for observational studies of BE patients. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using a random effects model for the association BE with hiatal hernia, cigarette smoking and colonic tumors. Results A positive relationship was observed between BE and hiatal hernia, which remained even after adjusting for reflux. Cigarette smoking was associated with an increased risk of BE. This was reflected in subgroup analyses of ever-, current- and former-smokers. BE was also associated with colonic tumors. The relationship was observed with both benign adenomatous tumors as well as with colorectal cancer, though it was stronger for colorectal cancer. Conclusions The association between BE and hiatal hernia is stronger for long segment BE when compared with short segment BE, and it appears to be independent of reflux. BE patients are also more likely to have ever smoked cigarettes. BE is associated with colonic tumors, with the association being stronger with colorectal cancer than with benign lesions

Contemporary outcomes after surgical aortic valve replacement with bioprostheses and allografts: a systematic review and meta-analysis(aEuro)

Many observational studies have reported outcomes after surgical aortic valve replacement (AVR), but there are no recent systematic reviews and meta-analyses including all available bioprostheses and allografts. The objective of this study is to provide a comprehensive and up-to-date overview of the outcomes after AVR with bioprostheses and allografts reported in the last 15 years. We conducted a systematic literature review (PROSPERO register: CRD42015017041) of studies published between 2000–15. Inclusion criteria were observational studies or randomized controlled trials reporting on outcomes of AVR with bioprostheses (stented or stentless) or allografts, with or without coronary artery bypass grafting (CABG) or valve repair procedure, with study population size n ≥ 30 and mean follow-up length ≥5 years. Fifty-four bioprosthesis studies and 14 allograft studies were included, encompassing 55 712 and 3872 patients and 349 840 and 32 419 patient-years, respectively. We pooled early mortality risk and linearized occurrence rates of valve-related events, reintervention and late mortality in a random-effects model. Sensitivity, meta-regression and subgroup analyses were performed to investigate the influence of outliers on the pooled estimates and to explore sources of heterogeneity. Funnel plots were used to investigate publication bias. Pooled early mortality risks for bioprostheses and allografts were 4.99% (95% confidence interval [CI], 4.44–5.62) and 5.03% (95% CI, 3.61–7.01), respectively. The late mortality rate was 5.70%/patient-year (95% CI, 4.99–5.62) for bioprostheses and 1.68%/patient-year (95% CI, 1.23–2.28) for allografts. Pooled reintervention rates for bioprostheses and allografts were 0.75%/patient-year (95% CI, 0.61–0.91) and 1.87%/patient-year (95% CI, 1.52–2.31), respectively. There was substantial heterogeneity in most outcomes. Meta-regression analyses identified covariates that could explain the heterogeneity: implantation period, valve type, patient age, gender, pre-intervention New York Heart Association class III/IV, concomitant CABG, study design and follow-up length. There is possible publication bias in all outcomes. This comprehensive systematic review and meta-analysis provides an overview of the outcomes after AVR with bioprostheses and allografts reported during the last 15 years. The results of this study can support patients and doctors in the prosthetic valve choice and can be used in microsimulation models to predict patient outcomes and estimate the cost-effectiveness of AVR with bioprostheses or allografts compared with current and future heart valve prostheses