Mortality in Barrett's oesophagus:Results from a population based study

Background: Patients with Barrett's oesophagus have an increased risk of oesophageal adenocarcinoma but this cancer only accounts for a small proportion of deaths in these patients. Other causes of death are reportedly raised in this group. We examined cause specific mortality among individuals in a population based Barrett's oesophagus register. Methods: We constructed a register of all patients diagnosed with columnar mucosa (including specialised intestinal metaplasia) of the oesophagus within Northern Ireland between 1993 and 1999. Deaths occurring within this cohort until 31 December 2000 were identified and mortality rates were compared with the general population. Results: Overall mortality was not raised in Barrett's patients. During 7413 person years of follow up in 2373 patients there were 253 deaths (standardised mortality ratio (SMR) 96 (95% confidence interval (CI) 84-107)). Mortality from oesophageal cancer was raised in patients with specialised intestinal metaplasia (SMR 774 (95% CI 317-1231 )) but only 4.7% of patients died from this cancer. Mortality from stroke (SMR 65 (95% CI 37-93)) was significantly lower than the general population while mortality from non-cancerous digestive system diseases was significantly higher (SMR 211 (95% CI 111-311)). Mortality rates from all other causes were similar to those of the general population. Conclusions: This study demonstrates that the overall mortality rate in patients with Barrett's oesophagus is closely similar to that of the general population. Oesophageal cancer mortality was raised but is an uncommon cause of death in these patients who also appear to have a reduced risk of death from stroke.

Review of: Whitehouse, R. 1993 Underground Religion: cult and culture in prehistoric Italy. Accordia Specialist Studies on Italy 1. London, University of London.

Malone , C., . Antiquity, 1993. 67(256): p. 686-7.

Induction of alloxan/streptozotocin diabetes in dogs: a revised experimental technique

The diabetic dog represents an excellent model for use in many aspects of diabetic research. The present paper describes, in detail, a reproducible experimental protocol for the successful induction of chemical diabetes in beagles using a combination of the 2 pancreatic beta-cell cytoxic agents alloxan and streptozotocin.

Incidence of colorectal cancer in a population-based cohort of patients with Barrett's oesophagus

Objective. Previous studies have shown a positive association between colorectal cancer and Barrett's oesophagus, but this association is disputed. No population-based studies have examined the incidence of this cancer in patients with Barrett's oesophagus. Material and methods. The present study comprised a population-based cohort of patients with Barrett's oesophagus (constructed using pathology reports of all oesophageal biopsies in Northern Ireland 1993-99; cohort subclassified according to whether specialized intestinal metaplasia (SIM) was present, absent, or not commented on in biopsies). Cases of colorectal cancer were identified by linking with the Northern Ireland Cancer Registry. The comparison group used was the general population in Northern Ireland. Results. A total of 2969 patients with Barrett's oesophagus were followed for a total of 14,014 person-years (mean 4.7 years). SIM was present in 1670 patients (56.2%), absent in 545 (18.4%) and not commented on in 754 (25.4%). Colorectal cancer was diagnosed in 39 patients; 22 patients had cancer diagnosed at least 6 months after diagnosis of Barrett's oesophagus. There was no increased risk of colorectal cancer: the standardized incidence ratio (SIR) for cancer diagnosed at least 6 months after entry into the cohort was 0.82 (95% CI, 0.48-1.17); this risk did not alter with SIM status or gender. To assess a possible effect of diagnostic bias, we calculated SIRs for cancers occurring after at least 3 months, after at least 1 month and at any time after diagnosis of Barrett's oesophagus. These were 0.94 (0.57-1.30), 1.09 (0.69-1.48) and 1.46 (1.00-1.92), respectively. Conclusions. The incidence of colorectal cancer was not elevated in patients with Barrett's oesophagus. Diagnostic bias may explain why previous studies have found an association. © 2005 Taylor & Francis.

Genome-wide association meta-analysis of human longevity identifies a novel locus conferring survival beyond 90 years of age

The genetic contribution to the variation in human lifespan is approximately 25%.  Despite the large number of identified disease-susceptibility loci, it is not known which loci influence population mortality.  We performed a genome-wide association meta-analysis of 7729 long-lived individuals of European descent (≥ 85 years) and 16121 younger controls (< 65 years) followed by replication in an additional set of 13060 long-lived individuals and 61156 controls. In addition, we performed a subset analysis in cases ≥ 90 years. We observed genome-wide significant association with longevity, as reflected by survival to ages beyond 90 years, at a novel locus, rs2149954, on chromosome 5q33.3 (OR = 1.10, P =1.74 x 10-8). We also confirmed association of rs4420638 on chromosome 19q13.32 (OR = 0.72, P = 3.40 x 10-36), representing the TOMM40/APOE/APOC1 locus. In a prospective meta-analysis (n = 34103) the minor allele of rs2149954 (T) on chromosome 5q33.3 associates with increased survival (HR = 0.95, P = 0.003). This allele has previously been reported to associate with low blood pressure in middle age. Interestingly, the minor allele (T) associates with decreased cardiovascular mortality risk, independent of blood pressure. We report on the first GWAS-identified longevity locus on chromosome 5q33.3 influencing survival in the general European population. The minor allele of this locus associates with low blood pressure in middle age, although the contribution of this allele to survival may be less dependent on blood pressure. Hence, the pleiotropic mechanisms by which this intragenic variation contributes to lifespan regulation have to be elucidated.

Defining the role of common variation in the genomic and biological architecture of adult human height

Using genome-wide data from 253,288 individuals, we identified 697 variants at genome-wide significance that together explained one-fifth of the heritability for adult height. By testing different numbers of variants in independent studies, we show that the most strongly associated 1/42,000, 1/43,700 and 1/49,500 SNPs explained 1/421%, 1/424% and 1/429% of phenotypic variance. Furthermore, all common variants together captured 60% of heritability. The 697 variants clustered in 423 loci were enriched for genes, pathways and tissue types known to be involved in growth and together implicated genes and pathways not highlighted in earlier efforts, such as signaling by fibroblast growth factors, WNT/I 2-catenin and chondroitin sulfate-related genes. We identified several genes and pathways not previously connected with human skeletal growth, including mTOR, osteoglycin and binding of hyaluronic acid. Our results indicate a genetic architecture for human height that is characterized by a very large but finite number (thousands) of causal variants.

New genetic loci link adipose and insulin biology to body fat distribution

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms.