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Paul Elliott

Publications and source records attributed to Paul Elliott.

44 records · Page 3Linked to original sources

Evaluating evidence on environmental health risks.

The assessment of adverse health effects from environmental hazards involves integration of evidence from a variety of sources, including experimental studies, both in animals and humans, in vitro studies, and epidemiological research. It requires an understanding of the sources, nature and levels of exposure to which humans may be subjected, the nature of the health outcome or toxic effect and the mechanisms by which this might occur, the relationship between dose and response, and a knowledge of the variability and susceptibility of potentially exposed populations. After outlining the process of risk assessment, this paper gives an overview of the most relevant human study methods used to investigate environment and health effects and discusses issues such as confounding and effect modification, that are important to consider when interpreting the results from such studies. Future challenges are outlined, such as increasing responsibility required by scientists to the sensitive issue of data protection and confidentiality, and also new opportunities, such as the increasing availability of computerized data, the incorporation of molecular epidemiological methods to aid the investigation of mechanistic pathways and gene-environment interactions, and the development and utilization of sophisticated statistical approaches.

Environmental Exposure↗

Relationship between birthweight and blood lipid concentrations in later life: evidence from the existing literature.

BACKGROUND: It has been suggested that there is a link between fetal growth and chronic diseases later in life. Several studies have shown a negative association between birthweight and cardiovascular diseases, as well as cardiovascular disease risk factors, such as blood pressure and type 2 diabetes. Far fewer studies have focused on the association between size at birth and blood lipid concentrations. We have conducted a qualitative assessment of the direction and consistency of the relationship between size at birth and blood lipid concentrations to see whether the suggested relationship between intrauterine growth and cardiovascular diseases is mediated by lipid metabolism. METHODS: A literature search covering the period January 1966 to January 2003 was performed using Medline, Embase, and Web of Science. All papers written in English and reporting the relationship between size at birth and lipid levels in humans were assessed. Bibliographies were searched for further publications. RESULTS: From an initial screen of 1198 references, 39 papers were included involving 28 578 individuals. There was no consistent relationship between size at birth and blood lipid levels; the one exception being triglyceride concentration, which showed statistically significant negative or U-shaped, but not positive, relationships with birthweight. CONCLUSION: This review does not strongly support a link between birthweight and blood lipid levels in later life. However, the research in this area is limited and in order to make any definitive conclusions, longitudinal studies with sufficient power, data, and prospective follow-up are needed.

Birth Weight↗

Temporal trends in orchidopexy, Great Britain, 1992-1998.

Concern has been expressed in recent years about worsening male reproductive health, possibly mediated by increasing exposures to environmental endocrine-disrupting agents. Trends suggested large increases in cryptorchidism in Britain and the United States between the 1950s and 1980s, although published data on recent trends have been scarce. We examined numbers of orchidopexy procedures, as a marker for cryptorchidism, using routine hospital admission data for England, Wales, and Scotland for fiscal years 1992-1993 through 1998-1999. Annual trends in orchidopexy rates were analyzed by age, in-patient admission versus day case, and geographical region. Orchidopexy rates were also obtained from the General Practice Research Database (GPRD) for England to cross-validate the hospital admissions data. Orchidopexy rates for boys 0-14 years old fell by 33% (from 23.5 to 15.8 per 10,000 population) between 1992 and 1998, with the steepest decline (50%) in 5-9-year-olds. The decreasing trend for 0-14-year-olds was evident in every region in England, in Wales, and in Scotland. Rates remained stable for men 15 or more years old, at 0.7 per 10,000. There was a marked shift from in-patient to day-case procedures. Rates from the GPRD showed a similar downward trend to the hospital data. Our findings could represent either an underlying decrease in the frequency of undescended testis or a fairly dramatic improvement in the diagnosis of cryptorchidism--resulting in fewer orchidopexies performed for retractile testis--in Great Britain during the 1990s, or both. Either way, our findings do not support the postulate of a recent worsening of male reproductive health of the scale suggested by some recent commentators on the endocrine disruptor hypothesis.

Adolescent↗

Geographical epidemiology of prostate cancer in Great Britain.

Prostate cancer incidence has increased during recent years, possibly linked to environmental exposures. Exposure to environmental carcinogens is unlikely to be evenly distributed geographically, which may give rise to variations in disease occurrence that is detectable in a spatial analysis. The aim of our study was to examine the spatial variation of prostate cancer in Great Britain at ages 45-64 years. Spatial variation was examined across electoral wards from 1975-1991. Poisson regression was used to examine regional, urbanisation and socioeconomic effects, while Bayesian mapping techniques were used to assess spatial variability. There was an indication of geographical differences in prostate cancer risk at a regional level, ranging from 0.83 (95% CI: 0.78-0.87) to 1.2 (95% CI: 1.1-1.3) across regions. There was significant heterogeneity in the risk across wards, although the range of relative risks was narrow. More detailed spatial analyses within 4 regions did not indicate any clear evidence of localised geographical clustering for prostate cancer. The absence of any marked geographical variability at a small-area scale argues against a geographically varying environmental factor operating strongly in the aetiology of prostate cancer.

Bayes Theorem↗

Changing international trends in mortality rates for liver, biliary and pancreatic tumours.

BACKGROUND/AIMS: The age-standardized mortality rate for hepatocellular carcinoma is increasing in several countries. However, in England and Wales we previously reported an increase in mortality rates from intrahepatic cholangiocarcinoma. Trends in cholangiocarcinoma in most other industrialized countries are unknown. To further study trends in hepatobiliary and pancreatic tumours, we analysed mortality data from the United States, Japan, Australia and Europe. METHODS: Age-standardized mortality rates for men and women for subcategories of liver tumours, tumours of the gall bladder and extrahepatic biliary tree and pancreas from 1979 to 1998 were obtained from the World Health Organization mortality database. RESULTS: We confirmed previously reported increases in hepatocellular carcinoma, but also found increases in other countries, particularly Australia (3-year average rise from 1.20 to 2.27, men). Mortality for intrahepatic cholangiocarcinoma increased in men in all countries studied, with the largest increases in Australia (from 0.10 to 0.70) and England and Wales (from 0.20 to 0.83). CONCLUSIONS: We present a hitherto unreported rise in age-standardized mortality rates from intrahepatic cholangiocarcinoma across four continents. The cause remains uncertain. An impact on the observed trends of improved diagnostic techniques and death certificate misclassification cannot be completely ruled out. Future research should include epidemiological studies to examine possible case-clustering and investigation of potential aetiological and host factors.

Australia↗