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Future Risk (future + risk)
Selected Abstracts,Normal for Now' or ,At Future Risk': A Double Standard for Selecting Young and Older Living Kidney DonorsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 4 2010R. W. Steiner Transplant centers medically evaluate potential living kidney donors in part to determine their baseline remaining lifetime risk for end stage renal disease (ESRD). If baseline risk is increased by the presence of a risk factor for ESRD, donation is often refused. However, as only about 13% of ESRD occurs in the general population by age 44, a normal medical evaluation cannot be expected to significantly reduce the 7% lifetime risk for a ,normal' 25-year-old black donor or the 2,3% risk for a similar white donor. About half of newly diagnosed ESRD in the United States occurs by age 65, and about half of that is from diabetic nephropathy, which takes about 25 years to develop. Therefore, the remaining baseline lifetime risk for ESRD is significantly lower in the normal, nondiabetic 55-year-old donor candidate. Some older donors with an isolated medical abnormality such as mild hypertension will be at lower or about the same overall baseline lifetime risk for ESRD as are young ,normal' donor candidates. Transplant centers use a ,normal for now' standard for accepting young donors, in place of the long-term risk estimates that must guide selection of all donors. [source] Modeled Effects of Sagebrush-Steppe Restoration on Greater Sage-Grouse in the Interior Columbia Basin, U.S.A.CONSERVATION BIOLOGY, Issue 5 2002Michael J. Wisdom Consequently, managers of FS,BLM lands need effective strategies to recover sagebrush (Artemisia spp.) habitats on which this species depends. In response to this need, we evaluated the potential benefits of two restoration scenarios on Greater Sage-Grouse in the interior Columbia Basin and adjacent portions of the Great Basin of the western United States. Scenario 1 assumed a 50% reduction in detrimental grazing effects (through changes in stocking rates and grazing systems) and a six-fold increase in areas treated with active restoration (e.g., prescribed burning, native seedings, wildfire suppression) compared with future management proposed by the FS,BLM. Scenario 2 assumed a 100% reduction in detrimental grazing effects and the same increase in active restoration as scenario 1. To evaluate benefits, we estimated the risk of population extirpation for sage grouse 100 years in the future under the two scenarios and compared this risk with that estimated for proposed (100-year) FS,BLM management. We used estimates of extirpation risk for historical (circa 1850,1890) and current time periods as a context for our comparison. Under historical conditions, risk of extirpation was very low on FS,BLM lands, but increased to a moderate probability under current conditions. Under proposed FS,BLM management, risk of extirpation on FS,BLM lands increased to a high probability 100 years in the future. Benefits of the two restoration scenarios, however, constrained the future risk of extirpation to a moderate probability. Our results suggest that expansive and sustained habitat restoration can maintain desired conditions and reduce future extirpation risk for sage grouse on FS,BLM lands in western North America. The continued spread of exotic plants, however, presents a formidable challenge to successful restoration and warrants substantial research and management attention. Resumen: Los hábitats del urogallo (Centrocercus urophasianus) han disminuido a lo largo de la región occidental de Norteamérica, y la mayoría de los hábitats restantes ocurren en terrenos administrados por el Servicio Forestal de E.U.A. (SF) y el Buró de Administración de Tierras ( BAT ). Por lo tanto, los encargados de las tierras SF,BAT necesitan estrategias eficaces para recuperar los hábitats de artemisa (Artemisia spp.) de los cuales depende esta especie. En respuesta a esta necesidad, evaluamos los beneficios potenciales de dos escenarios de restauración sobre el urogallo en el interior de la Cuenca del Columbia y porciones adyacentes de la Gran Cuenca del occidente de los Estados Unidos. El escenario 1 supone una reducción del 50% en los efectos perjudiciales del pastoreo ( por medio de cambios en las tasas de aprovisionamiento y en los sistemas de pastoreo) y un incremento de seis veces en la superficie de las áreas tratadas con restauración activa ( por ejemplo, quemas prescritas, plántulas nativas, supresión de fuego no controlado) comparada con la administración futura propuesta por el SF,BAT. El escenario 2 supone una reducción del 100% en los efectos de pastoreo perjudiciales y el mismo aumento en la restauración activa que en el escenario 1. Para evaluar los beneficios, estimamos el riesgo de extirpación de la población de urogallos en 100 años bajo los dos escenarios y comparamos este riesgo con el riesgo estimado por la propuesta de manejo de SF,BAT (100-años). Utilizamos estimaciones del riesgo de extirpación en períodos históricos (entre 1850 y 1890) y actuales como contexto para nuestra comparación. Bajo condiciones históricas, el riesgo de extirpación fue muy bajo en los terrenos SF,BAT pero aumentó a una probabilidad moderada bajo condiciones actuales. Bajo la administración propuesta por SF,BAT, el riesgo de extirpación en los terrenos SF,BAT aumentó a una alta probabilidad 100 años en el futuro. Sin embargo, los beneficios de los dos escenarios de restauración constriñen el riesgo de extirpación a una probabilidad moderada. Nuestros resultados sugieren que la restauración expansiva y sostenida del hábitat puede mantener condiciones deseadas y reduce el riesgo de extirpación de urogallos en terrenos SF,BAT en la región occidental de Norteamérica. Sin embargo, la continua extensión de plantas exóticas representa un reto formidable para la restauración exitosa y justifica considerable investigación y atención de manejo. [source] Can hepatitis C virus prevalence be used as a measure of injection-related human immunodeficiency virus risk in populations of injecting drug users?ADDICTION, Issue 2 2010An ecological analysis ABSTRACT Background Human immunodeficiency virus (HIV) outbreaks occur among injecting drug users (IDUs), but where HIV is low insight is required into the future risk of increased transmission. The relationship between hepatitis C virus (HCV) and HIV prevalence among IDUs is explored to determine whether HCV prevalence could indicate HIV risk. Methods Systematic review of IDU HIV/HCV prevalence data and regression analysis using weighted prevalence estimates and time,series data. Results HIV/HCV prevalence estimates were obtained for 343 regions. In regions other than South America/sub-Saharan Africa (SAm/SSA), mean IDU HIV prevalence is likely to be negligible if HCV prevalence is <30% (95% confidence interval 22,38%) but increases progressively with HCV prevalence thereafter [linearly (, = 0.39 and R2 = 0.67) or in proportion to cubed HCV prevalence (, = 0.40 and R2 = 0.67)]. In SAm/SSA, limited data suggest that mean HIV prevalence is proportional to HCV prevalence (, = 0.84, R2 = 0.99), but will be much greater than in non-SAm/SSA settings with no threshold HCV prevalence that corresponds to low HIV risk. At low HCV prevalences (<50%), time,series data suggest that any change in HIV prevalence over time is likely to be much smaller (<25%) than the change in HCV prevalence over the same time-period, but that this difference diminishes at higher HCV prevalences. Conclusions HCV prevalence could be an indicator of HIV risk among IDUs. In most settings, reducing HCV prevalence below a threshold (30%) would reduce substantially any HIV risk, and could provide a target for HIV prevention. [source] Total and soluble fluorine concentrations in relation to properties of soils in New ZealandEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 3 2006P. Loganathan Summary Soil fluorine (F) concentrations continue to increase in agricultural soils receiving regular applications of phosphatic fertilizer. Continued accumulation of soil F poses a risk to grazing ruminants and may pose a future risk to groundwater quality. This paper examines the range of total F (Ft) concentrations and forms of soluble F species and their relationship to selected soil properties in New Zealand agricultural soils. The Ft and soluble F (soil F extracted with water (Fwater) and 0.01 m KCl (FKCl)) concentrations in 27 soil samples (0,75 mm depth) taken from predominantly pasture sites in the North and South Islands of New Zealand were much less than those reported in the literature for sites contaminated with F from industry. The Ft concentrations ranged from 212 to 617 µg F g,1 soil. The F-toxicity risk to grazing animals in farms at these sites through soil ingestion is small at present, but farms with very large Ft concentrations (i.e. > 500 µg F g,1) need to adopt suitable grazing and fertilizer management practices to avoid future F-toxicity risk. The Ft concentration had very strong positive correlations with both total soil P and total soil Cd concentrations, reflecting the link between P fertilizer use and F accumulation in the soils. It also had significant positive correlations with organic matter and amorphous Al oxides contents, indicating that F is strongly bound to Al polymers adsorbed to organic matter and amorphous Al oxides. The Fwater and FKCl concentrations and free F, ion concentrations in water (F,water) and 0.01 m KCl (F,KCl) extracts were generally two and three orders of magnitude, respectively, less than the Ft concentrations and were much less than the concentrations considered phytotoxic. The Fwater and FKCl concentrations were positively related to soil organic matter content and negatively related to soil pH. Regression models relating Fwater and FKCl concentrations to soil organic matter content and soil pH suggest that F can be very soluble in extremely acidic soils (pH(water) < 4.9) with large organic matter contents and therefore F potentially may contaminate groundwater if these soils are also coarse-textured and the water table is shallow. [source] Low adiponectin levels are associated with renal cell carcinoma: A case-control studyINTERNATIONAL JOURNAL OF CANCER, Issue 7 2007Themistoklis N. Spyridopoulos Abstract Adiponectin is a novel endogenous insulin sensitizer, secreted by mature adipocytes. Circulating levels of adiponectin are inversely associated with obesity and insulin resistance. Because obesity is a risk factor for renal cell carcinoma (RCC), we hypothesized that low adiponectin levels are associated with RCC. To evaluate this hypothesis, we conducted a case- control study of 70 patients with histologically confirmed RCC and 280 healthy controls matched by gender, age and county of residence. Study subjects were interviewed and blood samples were collected during a 32-month period in Athens, Greece. Serum adiponectin levels were statistically, significantly and inversely associated with RCC when compared with controls (OR = 0.76, p = 0.05) and this association remained practically unchanged after controlling for BMI; the introduction of waist to hip ratio along with adiponectin in the multiple logistic regression analysis model rendered the association between adiponectin and RCC risk insignificant, indicating that altered levels of adiponectin may mediate the effect of central or intra-abdominal obesity on RCC. Prospective studies as well as studies exploring underlying mechanisms are needed to fully explore the role of adiponectin in predicting future risk of RCC in humans. © 2006 Wiley-Liss, Inc. [source] The COMT val158met Polymorphism Is Associated With Peak BMD in Men,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 12 2004Mattias Lorentzon Abstract The associations between the functional val158met polymorphism of the estrogen-degrading COMT enzyme and skeletal properties in young men were investigated. BMD was associated with COMT genotype. Introduction: Peak BMD is an important predictor of future risk of osteoporosis, and it is to a large extent determined by genetic factors. Estrogens are involved in the accretion of bone mass during puberty. Catechol- O -methyltransferase (COMT) is involved in the degradation of estrogens. There is a functional polymorphism in the COMT gene (val158met), resulting in a 60,75% difference in enzyme activity between the val (high activity [H]) and met (low activity [L]) variants. The aim of this cross-sectional study was to investigate the associations between this polymorphism and peak BMD in young men. Materials and Methods: A total of 458 healthy men (mean age, 19 ± 0.6 years) were genotyped and classified as COMTLL, COMTHL, or COMTHH. Areal BMD (aBMD) was measured by DXA. Cortical and trabecular volumetric BMD (vBMD) were measured by pQCT. The associations between COMT genotype and skeletal phenotypes were determined. Results and Conclusions: Regression models using physical activity, height, weight, age, and COMT genotype as covariates showed that COMT genotype was an independent predictor of aBMD in the total body and in all femur locations investigated, but not in the spine. The values for COMTHL and COMTHH were very similar, and therefore, they were pooled into one group. aBMD at Ward's triangle, trochanter, and total femur were 4.9%, 4.5%, and 3.7% lower, respectively, in the COMTLL than in the COMTHL/HH group (p < 0.01). pQCT analyses showed that COMT genotype was an independent predictor of trabecular vBMD of the tibia, radius, and fibula. Trabecular vBMD of the radius and fibula in COMTLL was 5.3% and 7.4% lower, respectively, than that of the combined COMTHL/HH group. COMT genotype was associated with cortical vBMD but not with cortical cross-sectional area in the tibia. These findings show that the COMT polymorphism is associated with BMD in young adult men. [source] Climate change scenarios and models yield conflicting predictions about the future risk of an invasive species in North AmericaAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 3 2010Anna M. Mika 1The pea leafminer Liriomyza huidobrensis (Blanchard) (Diptera: Agromyzidae) is an invasive species in North America and a serious economic pest on a wide variety of crops. We developed a bioclimatic envelope model (BEM) for this species and examined the envelope's potential location in North America under various future climates. 2We compared the future bioclimatic envelopes for L. huidobrensis using either simple scenarios comprising uniform changes in temperature/precipitation or climate projections from general circulation models (GCMs). Our simple scenarios were: (i) an increase of 0.1°C per degree in latitude with a 20% increase in summer precipitation and a 20% decrease in winter precipitation and (ii) an overall increase of 3°C everywhere, also with the same changes in precipitation. For GCM-modelled climate change, we used the Canadian Centre for Climate Modelling and Analysis GCM (CGCM2) and the Hadley Centre climate model (HadCM3), each in combination with two scenarios from the Special Report on Emissions Scenarios (A2 and B2). 3The BEM results using the simple scenarios were more similar to each other than to the results obtained using GCM projections. The results were also qualitatively different (i.e. spatially different and divergent) depending on which GCM-scenario combination was used. 4This modelling exercise illustrates that: (i) results using first approximation simple climate change scenarios can give predictions very different from those that use GCM-modelled climate projections (comprising a result that has worrying implications for empirical impact research) and that (ii) different GCM-models using the same scenario can give very different results (implying strong model dependency in projected biological impacts). [source] Bone Mineral Density in Adolescent Women Using Depot Medroxyprogesterone AcetateJOURNAL OF THE AMERICAN ACADEMY OF NURSE PRACTITIONERS, Issue 2 2004Nancy H. Busen PhD Purpose To present current data on bone mineral density (BMD) in adolescent women using the long-acting contraceptive depot medroxyprogesterone acetate (DMPA) and also to discuss the importance of developing maximal bone mass during adolescence to offset bone demineralization later in life. Data Sources Research-based articles in the medical literature, review articles, and recommendations from the American Academy of Pediatrics and the National Osteoporosis Foundation. Conclusions Osteoporosis is a preventable disease that affects millions of Americans, particularly older women. Factors influencing the attainment and maintenance of peak bone mass during childhood and adolescence affect the future risk of fractures. Although longitudinal studies conducted on adolescent women using DMPA are very limited, findings suggest that adolescents are losing bone density during a time of expected bone accretion. Implications for Practice Clinicians must consider all the risks and benefits when prescribing contraceptives to adolescents. By themselves, the findings related to BMD and DMPA use by adolescents are not sufficient to limit the use of DMPA as a contraceptive method. However, clinicians must take into account the addition of other modifying factors associated with BMD that may contribute to overall bone loss in adolescent females. More prospective data on the long-term use of DMPA by adolescents are needed to determine DMPA's effect on bone loss and to determine if bone loss is transient in adolescents. [source] HDL-cholesterol and future risk of venous thromboembolism: the Tromsø StudyJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 8 2009S. K. BRÆKKAN [source] Budesonide/formoterol for maintenance and reliever therapy in the management of moderate to severe asthmaALLERGY, Issue 12 2008M. Humbert The Global Initiative for Asthma (GINA) guidelines aim at improving asthma control and preventing future risk. For patients with moderate to severe asthma an inhaled corticosteroid (ICS) or an ICS/long-acting ,2 -agonist (LABA) combination with a short-acting ,2 -agonist (SABA) as reliever is recommended. Despite the availability of effective maintenance therapies, a large proportion of patients still fail to achieve guideline-defined asthma control, and overuse of SABA reliever medication at the expense of ICS is commonly observed. New simplified treatment approaches may offer a solution and assist physicians to achieve overall asthma control. One such treatment approach, which is recommended in the GINA guidelines, is budesonide/formoterol for both maintenance and reliever therapy. This treatment strategy significantly reduces the rate of severe asthma exacerbations compared with ICS/LABA plus SABA and achieves equivalent daily symptom control compared with higher doses of ICS/LABA plus separate SABA for relief. These benefits are achieved at a lower overall steroid load, and budesonide/formoterol maintenance and reliever therapy is well tolerated in patients with moderate to severe asthma. This review discusses current asthma management in patients with moderate to severe disease and examines the evidence for alternative asthma management approaches. [source] Childhood asthma epidemiology: Insights from comparative studies of rural and urban populations,PEDIATRIC PULMONOLOGY, Issue 2 2008Gary W.K. Wong MD Abstract Asthma is one of the most common chronic respiratory disorders. Many epidemiology studies have suggested an increasing trend of asthma in many different regions of the world but the exact reasons explaining such trend remain unclear. Nevertheless, changing environmental factors are most likely important in explaining the trend of asthma. Studies in the past decade have clearly shown a mark difference in the prevalence between urban and rural regions. The consistent findings of a markedly lower prevalence of asthma in children and adults who have been brought up in a farming environment clearly indicate the importance of environmental influence of asthma development. Although the exact protective environmental factors in the rural region remain to be defined, there have been many studies suggesting that early exposure to microbes or microbial products may play a role in modulating the immune system so as to reduce the future risk of asthma and allergies. Advances in the understanding of the genetic predisposition and how these genetic factors may interact with specific environment factors are of paramount importance for the future development of primary preventive strategies for asthma. Pediatr Pulmonol. 2008; 43:107,116. © 2007 Wiley-Liss, Inc. [source] Post-transplant glucose status in 61 pediatric renal transplant recipients: Preliminary results of five Turkish pediatric nephrology centersPEDIATRIC TRANSPLANTATION, Issue 2 2010Necla Buyan Buyan N, Bilge I, Turkmen MA, Bayrakci U, Emre S, Fidan K, Baskin E, Gok F, Bas F, Bideci A. Post-transplant glucose status in 61 pediatric renal transplant recipients: Preliminary results of five Turkish pediatric nephrology centers. Pediatr Transplantation 2010:14:203,211 © 2009 John Wiley & Sons A/S. Abstract:, To assess the incidence, risk factors and outcomes of PTDM, a total of 61 non-diabetic children (24 girls, 37 boys, age: 14.5 ± 2.1 yr) were examined after their first kidney transplantation (37.3 ± 21.6 months) with an OGTT. At baseline, 16 (26.2%) patients had IGT, 45 (73.8%) had NGT, and no patient had PTDM. No significant difference was shown between TAC- and CSA-treated patients in terms of IGT. Higher BMI z -scores (p = 0.011), LDL-cholesterol (p < 0.05) and triglyceride levels (p < 0.01), HOMA-IR (p = 0.013) and lower HOMA-%, (p = 0.011) were significantly associated with IGT. Fifty-four patients were re-evaluated after six months; eight patients with baseline IGT (50%) improved to NGT, three (19%) developed PTDM requiring insulin therapy, five (31%) remained with IGT, and four patients progressed from NGT to either IGT (two) or PTDM (two). These 12 progressive patients had significantly higher total cholesterol (p < 0.05), triglycerides (p < 0.05), HOMA-IR (p < 0.01) and lower HOMA-%, (p < 0.0) than non-progressive patients at baseline. We can conclude that post-transplantation glucose abnormalities are common in Turkish pediatric kidney recipients, and higher BMI z -scores and triglyceride concentrations are the main risk factors. Considering that the progressive patients are significantly more insulin resistant at baseline, we suggest that the utility of both HOMA-IR and HOMA-%, in predicting future risk of PTDM and/or IGT should be evaluated in children. [source] Electron Beam Computed Tomographic Scanning in Preventive MedicinePREVENTIVE CARDIOLOGY, Issue 2 2002David G. King BSc Undetected coronary atherosclerosis is present in the majority of patients suffering myocardial infarction or sudden death. Electron beam computed tomography affords noninvasive scanning of the heart to detect and measure coronary calcification. These data permit dramatically improved assessment of both short term and future risk for cardiac and other events. Knowledge of this risk gives the physician an opportunity for timely and cost-effective interventions. [source] Approaches for assessing hazards and risks to workers and the public from contaminated landREMEDIATION, Issue 1 2007Michael Gochfeld Many public agencies and private entities are faced with assessing the risks to humans from contamination on their lands. The United States Department of Energy (US DOE) and Department of Defense are responsible for large holdings of contaminated land and face a long-term and costly challenge to assure sustainable protectiveness. With increasing interest in the conversion of brownfields to productive uses, many former industrial properties must also be assessed to determine compatible future land uses. In the United States, many cleanup plans or actions are based on the Comprehensive Environmental Responsibility, Compensation, and Liability Act, which provides important but incomplete coverage of these issues, although many applications have tried to involve stakeholders at multiple steps. Where there is the potential for exposure to workers, the public, and the environment from either cleanup or leaving residual contamination in place, there is a need for a more comprehensive approach to evaluate and balance the present and future risk(s) from existing contamination, from remediation actions, as well as from postremediation residual contamination. This article focuses on the US DOE, the agency with the largest hazardous waste remediation task in the world. Presented is a framework extending from preliminary assessment, risk assessment and balancing, epidemiology, monitoring, communication, and stakeholder involvement useful for assessing risk to workers and site neighbors. Provided are examples of those who eat fish, meat, or fruit from contaminated habitats. The US DOE's contaminated sites are unique in a number of ways: (1) huge physical footprint size, (2) types of waste (mixed radiation/chemical), and (3) quantities of waste. Proposed future land uses provide goals for remediation, but since some contamination is of a type or magnitude that cannot be cleaned up with existing technology, this in turn constrains future land use options, requiring an iterative approach. The risk approaches must fit a range of future land uses and end-states from leave-in-place to complete cleanup. This will include not only traditional risk methodologies, but also the assessment and surveillance necessary for stewards for long-term monitoring of risk from historic and future exposure to maintain sustainable protectiveness. Because of the distinctiveness of DOE sites, application of the methodologies developed here to other waste site situations requires site-specific evaluation © 2007 Wiley Periodicals, Inc. [source] Transient anomalies in genital appearance in some extremely preterm female infants may be the result of foetal programming causing a surge in LH and the over activation of the pituitary,gonadal axisCLINICAL ENDOCRINOLOGY, Issue 5 2008Ronda Greaves Summary Aim, Animal studies have linked foetal programming with the development of the polycystic ovarian syndrome, and metabolic syndrome, in adulthood. The objective is to describe the investigation of four extreme-premature female infants born between 25 and 29 weeks' gestation with apparent genital abnormalities in association with unusually high androgens and gonadotrophins, to postulate a cause and to raise awareness of pitfalls in assessment of these infants. Methods, Clinical examination and biochemical evaluation of four infants referred for apparent congenital ambiguity. Results, Female gender was assigned at birth. Chromosome analysis confirmed 46XX, urine steroid profiles demonstrated no evidence of congenital adrenal hyperplasia and only the expected levels of foetal adrenal steroids. Elevated LH (up to 162 IU/l), testosterone (up to 2·6 nmol/l), ,4 androstenedione (up to > 35 nmol/l) and dehydro-epiandrosterone sulphate (DHEAS) (up to 26·6 µmol/l) were seen in all four infants. These decreased over time but were significantly different from a control population of premature infants of similar gestational age. Conclusions, We postulate that the clinical pattern of apparent clitoral enlargement in some extremely premature infants may reflect true temporary virilization due to an unusually high (or excessive) LH surge, in turn causing high foetal androgens. Foetal programming of gonadotrophin excess is probably the primary cause of androgen increase, in turn causing virilization, in some extreme-premature infants. These may potentially be a group at future risk of polycystic ovary or metabolic syndrome, however, further work needs to be conducted to substantiate this hypothesis. [source] Environmental Risk and Uncertainty: Insights from Yucca MountainJOURNAL OF REGIONAL SCIENCE, Issue 3 2003Mary Riddel Using data from a survey of southern Nevada households, we develop a model,based subjective risk estimate for each household. We then explore different factors that may influence the household's location decisions if the proposed transportation route is ultimately chosen for nuclear waste transport. We extend the conventional expected utility model to allow for uncertainty surrounding the actual risks borne by the household. Finally, we examine the impact of federal government compensation on households' location decisions. The findings indicate that residents currently living near the proposed transportation route express subjective risk estimates much larger than those reported by the Department of Energy. In general, households that are uncertain about the future risks are more likely to relocate than those expressing certainty. When everything is considered, the model predicts that between one and three percent of households living near the transportation route are likely to relocate. Compensation can influence some households to remain at their present location and bear the transport risk. [source] Mortality among unionized construction plasterers and cement masons,AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 4 2001Frank Stern Abstract Background Plasterers perform a variety of duties including interior and exterior plastering of drywall, cement, stucco, and stone imitation; the preparation, installation, and repair of all interior and exterior insulation systems; and the fireproofing of steel beams and columns. Some of the current potential toxic exposures among plasterers include plaster of Paris, silica, fiberglass, talc, and 1,1,1-trichloroethylene; asbestos had been used by the plasterers in the past. Cement masons, on the other hand, are involved in concrete construction of buildings, bridges, curbs and gutters, sidewalks, highways, streets and roads, floors and pavements and the finishing of same, when necessary, by sandblasting or any other method. Exposures include cement dust, silica, asphalt, and various solvents. Methods Proportionate mortality ratios (PMRs) and proportionate cancer mortality ratios (PCMRs) were calculated for 99 causes of death among 12,873 members of the Operative Plasterers' and Cement Masons' International Association who died between 1972 and 1996 using United States age-, race-, and calender-specific death rates. Statistical significance (P value) of results was based upon the Poisson distribution. Results Among plasterers, statistically significant elevated mortality was observed for asbestosis, where the PMR reached 1,657 (P,<,0.01) with eleven observed deaths and less than one death expected, for lung cancer (PCMR,=,124, P,<,0.01), and for benign neoplasms (PMR,=,210, P,<,0.05). Among cement masons, statistically significant elevated mortality was observed for cancer of the stomach (PCMR,=,133, P,<,0.01), benign neoplasms (PMR,=,132, P,<,0.01), and poisonings (PMR,=,159, P,<,0.05). Except for poisonings, which were not thought to be occupationally related, all of the statistically significant results occurred among those members who entered the union prior to 1950. However, the risk for lung cancer among plasterers was still elevated among those entering the union after 1970 as was the risk for stomach cancer among cement masons who entered the union after 1950. Conclusions The present study suggests that plasterers and cement masons still have elevated risks for certain diseases, especially lung and stomach cancer. Therefore, union members currently living should be screened for asbestos-related diseases and educated about the future risks for these diseases. Am. J. Ind. Med. 39:373,388, 2001. Published 2001 Wiley-Liss, Inc. [source] Composite estimates of physiological stress, age, and diabetes in American SamoansAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2007Douglas E. Crews Abstract Composite estimates of physiological stress such as allostatic load (AL) were developed to help assess cumulative impacts of psychosocial and physical stressors on the body. Physiological responses to stress generally accelerate somatic wear-and-tear and chronic degenerative conditions (CDCs). Following McEwen (Neuropsychopharmacology 22 (1999) 108,124) and others, primary physiological mediators of somatic stress responses include glucocorticoids (cortisol), catecholamines (adrenaline and noradrenaline), and serum dihydroepiandosterone-sulfate (DHEA-S). Conversely, blood pressure (BP), serum HDL and total cholesterol, glycated hemoglobin (HbA1c), and waist/hip (w/h) ratio are modulated by such hormones, thereby acting as secondary mediators of stress response. When these risk factors are aggregated into a composite score, higher stress loads are associated with increased risks for days of school/work missed, functional losses, morbidity, and mortality in US samples. To examine stress loads in American Samoans, data on all 6 secondary mediators along with estimates of body habitus (i.e. height, weight, circumferences, skinfolds) and physiology (i.e. fasting insulin, LDLc, triglycerides, fasting glucose) were measured on 273 individuals residing on Tutuila Island in 1992. Four combinations of these physiological factors were used to determine composite estimates of stress. These were then assessed by sex for associations with age and the presence of diabetes. Composite estimates of stress load were higher in Samoan women than men. Associations with age tended to be low and negative in men, but positive in women, appearing to reflect cultural circumstances and population history. Stress load scores also were higher among those with diabetes than those without among both men and women. These results suggest that composite estimates of stress may be useful for assessing future risks of CDC's and the senescent processes that may underlie them in cross-cultural research. Am J Phys Anthropol, 2007. © 2007 Wiley-Liss, Inc. [source] Estimating the risk of rare complications: is the ,rule of three' good enough?ANZ JOURNAL OF SURGERY, Issue 7-8 2009John Ludbrook Abstract The clinical problem:, If a surgeon has performed a particular operation on n consecutive patients without major complications, what is the long-term risk of major complications after performing many more such operations? Examples of such operations are endoscopic cholecystectomy, nephrectomy and sympathectomy. The statistical problem and solutions:, This general problem has exercised the minds of theoretical statisticians for more than 80 years. They agree only that the long-term risk is best expressed as the upper bound of a 95% confidence interval. We consider many proposed solutions, from those that involve complex statistical theory to the empirical ,rule of three', popular among clinicians, in which the percentage risk is given by the formula 100 × (3/n). Our conclusions:, The ,rule of three' grossly underestimates the future risks and can be applied only when the initial complication rate is zero (that is, 0/n). If the initial complication rate is greater than zero, then no simple ,rule' suffices. We give the results of applying the more popular statistical models, including their coverage. The ,exact' Clopper,Pearson interval has wider coverage across all proportions than its nominal 95%, and is, thus, too conservative. The Wilson score confidence interval gives about 95% coverage on average overall population proportions, except very small ones, so we prefer it to the Clopper,Pearson method. Unlike all the other intervals, Bayesian intervals with uniform priors yield exactly 95% coverage at any observed proportion. Thus, we strongly recommend Bayesian intervals and provide free software for executing them. [source] |