Hypothetical mortality risk associated with spiral computed tomography of the maxilla and mandible

In the present study, dose measurements have been conducted following examination of the maxilla and mandible with spiral computed tomography (CT). The measurements were carried out with 2 phantoms, a head and neck phantom and a full body phantom. The analysis of applied thermoluminescent dosimeters yielded radiation doses for organs and tissues in the head and neck region between 0.6 and 16.7 mGy when 40 axial slices and 120 kV/165 mAs were used as exposure parameters. The effective dose was calculated as 0.58 and 0.48 mSv in the maxilla and mandible, respectively. Tested methods for dose reduction showed a significant decrease of radiation dose from 40 to 65%. Based on these results, the mortality risk was estimated according to calculation models recommended by the Committee on the Biological Effects of Ionizing Radiations and by the International Commission on Radiological Protection. Both models resulted in similar values. The mortality risk ranges from 46.2 x 10.6 for 20-year-old men to 11.2 x 10(-6) for 65-year-old women. Using 2 methods of dose reduction, the mortality risk decreased by approximately 50 to 60% to 19.1 x 10(-6) for 20-year-old men and 5.5 x 10(-6) for 65-year-old women. It can be concluded that a CT scan of the maxillofacial complex causes a considerable radiation dose when compared with conventional radiographic examinations. Therefore, a careful indication for this imaging technique and dose reduction methods should be considered in daily practice.

Domains of physical activity and all-cause mortality: systematic review and dose-response meta-analysis of cohort studies

Background The dose–response relation between physical activity and all-cause mortality is not well defined at present. We conducted a systematic review and meta-analysis to determine the association with all-cause mortality of different domains of physical activity and of defined increases in physical activity and energy expenditure. Methods MEDLINE, Embase and the Cochrane Library were searched up to September 2010 for cohort studies examining all-cause mortality across different domains and levels of physical activity in adult general populations. We estimated combined risk ratios (RRs) associated with defined increments and recommended levels, using random-effects meta-analysis and dose–response meta-regression models. Results Data from 80 studies with 1 338 143 participants (118 121 deaths) were included. Combined RRs comparing highest with lowest activity levels were 0.65 [95% confidence interval (95% CI) 0.60–0.71] for total activity, 0.74 (95% CI 0.70–0.77) for leisure activity, 0.64 (95% CI 0.55–0.75) for activities of daily living and 0.83 (95% CI 0.71–0.97) for occupational activity. RRs per 1-h increment per week were 0.91 (95% CI 0.87–0.94) for vigorous exercise and 0.96 (95% CI 0.93–0.98) for moderate-intensity activities of daily living. RRs corresponding to 150 and 300 min/week of moderate to vigorous activity were 0.86 (95% CI 0.80–0.92) and 0.74 (95% CI 0.65–0.85), respectively. Mortality reductions were more pronounced in women. Conclusion Higher levels of total and domain-specific physical activity were associated with reduced all-cause mortality. Risk reduction per unit of time increase was largest for vigorous exercise. Moderate-intensity activities of daily living were to a lesser extent beneficial in reducing mortality.

Effect of vagus nerve stimulation in an adult patient with Dravet syndrome: contribution to sudden unexpected death in epilepsy risk reduction?

We report on a patient who developed, from 5 months of age, multiple seizure types, including myoclonic, associated with severe psychomotor delay, leading to the diagnosis of Dravet syndrome. Over the years, he developed refractory epilepsy and was implanted with a vagus nerve stimulator at the age of 19. After 3 months, he experienced a progressive improvement of partial and generalized seizures, with a >90% reduction, and better alertness. This meaningful clinical improvement is discussed in the light of the sudden unexpected death in epilepsy risk, which is high in this setting, and seems remarkably diminished in our patient in view of the reduction of generalized convulsions.

Hypothetical mortality risk associated with spiral tomography of the maxilla and mandible prior to endosseous implant treatment

Radiation dose delivered from the SCANORA radiography unit during the cross-sectional mode for dentotangential projections was determined. With regard to oral implantology, patient situations of an edentulous maxilla and mandible as well as a single tooth gap in regions 16 and 46 were simulated. Radiation doses were measured between 0.2 and 22.5 mGy to organs and tissues in the head and neck region when the complete maxilla or mandible was examined. When examining a single tooth gap, only 8% to 40% of that radiation dose was generally observed. Based on these results, the mortality risk was estimated according to a calculation model recommended by the Committee on the Biological Effects of Ionizing Radiations. The mortality risk ranged from 31.4 x 10(-6) for 20-year-old men to 4.8 x 10(-6) for 65-year-old women when cross-sectional imaging of the complete maxilla was performed. The values decreased by 70% when a single tooth gap in the molar region of the maxilla was radiographed. The figures for the mortality risk for examinations of the complete mandible were similar to those for the complete maxilla, but the mortality risk decreased by 80% if only a single tooth gap in the molar region of the mandible was examined. Calculations according to the International Commission on Radiological Protection carried out for comparison did not reveal the decrease of the mortality risk with age and resulted in a higher risk value in comparison to the group of 35-year old individuals in calculations according to the Committee on the Biological Effects of Ionizing Radiations.

Mergers, executive risk reduction and stockholder wealth

Among the possible consequences of agency problems between owners and managers is a tendency by managers to make investment decisions for their firms that are deliberately aimed at reducing firm risk, as a means to control managers' personal wealth risk. The literature has suggested that such behavior may occur to the detriment of shareholder wealth, and that mrgers may be a particular class of investment decisions for which the behavior would be observable. We test these hypotheses empirically, but find no evidence from our merger sample that risk reduction for the aqquiring firm is the typical outcome nor that, when it occurs, it is differentially costly for shareholders.

International Frameworks for Disaster Risk Reduction: Useful Guidance for Sustainable Mountain Development?

In recent decades, a number of global frameworks have been developed for disaster risk reduction (DRR). The Hyogo Framework for Action 2005–2015 and its successor document, the Sendai Framework for Disaster Risk Reduction, adopted in Japan in March 2015, provide general guidance for reducing risks from natural hazards. This is particularly important for mountainous areas, but DRR for mountain areas and sustainable mountain development received little attention in the recent policy debate. The question remains whether the Hyogo and Sendai frameworks can provide guidance for sustainable mountain development. This article evaluates the 2 frameworks in light of the special challenges of DRR in mountain areas and argues that, while the frameworks offer valuable guidance, they need to be further adapted for local contexts—particularly for mountain areas, which require special attention because of changing risk patterns like the effects of climate change and high land-use pressure.

External validation of the Hospital-patient One-year Mortality Risk (HOMR) model for predicting death within 1 year after hospital admission

BACKGROUND Predicting long-term survival after admission to hospital is helpful for clinical, administrative and research purposes. The Hospital-patient One-year Mortality Risk (HOMR) model was derived and internally validated to predict the risk of death within 1 year after admission. We conducted an external validation of the model in a large multicentre study. METHODS We used administrative data for all nonpsychiatric admissions of adult patients to hospitals in the provinces of Ontario (2003-2010) and Alberta (2011-2012), and to the Brigham and Women's Hospital in Boston (2010-2012) to calculate each patient's HOMR score at admission. The HOMR score is based on a set of parameters that captures patient demographics, health burden and severity of acute illness. We determined patient status (alive or dead) 1 year after admission using population-based registries. RESULTS The 3 validation cohorts (n = 2,862,996 in Ontario, 210 595 in Alberta and 66,683 in Boston) were distinct from each other and from the derivation cohort. The overall risk of death within 1 year after admission was 8.7% (95% confidence interval [CI] 8.7% to 8.8%). The HOMR score was strongly and significantly associated with risk of death in all populations and was highly discriminative, with a C statistic ranging from 0.89 (95% CI 0.87 to 0.91) to 0.92 (95% CI 0.91 to 0.92). Observed and expected outcome risks were similar (median absolute difference in percent dying in 1 yr 0.3%, interquartile range 0.05%-2.5%). INTERPRETATION The HOMR score, calculated using routinely collected administrative data, accurately predicted the risk of death among adult patients within 1 year after admission to hospital for nonpsychiatric indications. Similar performance was seen when the score was used in geographically and temporally diverse populations. The HOMR model can be used for risk adjustment in analyses of health administrative data to predict long-term survival among hospital patients.

Cancer, a disease of aging (part 2) - risk factors for older adult cancer mortality in Switzerland 1991-2008

Cancer is disease of aging that disproportionately affects older adults and often results in considerable public health consequences. This study evaluated gender-age-specific cancer mortality risk factors in older adults in Switzerland with attention to the most common types of cancer.

[Microalbuminuria--a new cardiovascular risk factor?]

Microalbuminuria is an established risk factor for renal disease, especially in the diabetic population. Recent studies have shown that microalbuminuria has also a highly relevant predictive value for cardiovascular morbidity and mortality. From normal to overt proteinuria levels, albuminuria shows a continuous marked increase in cardiovascular risk. This association is independent of other "classical" cardiovascular risk factors such as hypertension, hyperlipidemia or smoking. Furthermore it has a predictive value not only for patients with diabetic or renal disease, but also for hypertensive individuals or the general population. Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers have been shown to display not only reno--but also cardioprotective effects. Their unique ability to lower albuminuria by 40% is related to a significant risk reduction in cardiovascular mortality. New clinical trials are needed to define "normal" albuminuria levels and how low we should go.

Stress-related reduction in personal mastery is associated with reduced immune cell beta2-adrenergic receptor sensitivity

Background: A growing body of literature suggests that caregiving burden is associated with impaired immune system functioning, which may contribute to elevated morbidity and mortality risk among dementia caregivers. However, potential mechanisms linking these relationships are not well understood. The purpose of this study was to investigate whether stress-related experience of depressive symptoms and reductions in personal mastery were related to alterations in ss2-adrenergic receptor sensitivity.Methods: Spousal Alzheimer's caregivers (N = 106) completed measures assessing the extent to which they felt overloaded by their caregiving responsibilities, experienced depressive symptoms, and believed their life circumstances were under their control. We hypothesized that caregivers reporting elevated stress would report increased depressive symptoms and reduced mastery, which in turn would be associated with reduced ss2- adrenergic receptor sensitivity on peripheral blood mononuclear cells (PBMC), as assessed by in vitro isoproterenol stimulation.Results: Regression analyses indicated that overload was negatively associated with mastery (beta = -0.36, p = 0.001) and receptor sensitivity (beta = -0.24, p = 0.030), whereas mastery was positively associated with receptor sensitivity (beta = 0.29, p = 0.005). Finally, the relationship between overload and receptor sensitivity diminshed upon simultaneous entry of mastery. Sobel's test confirmed that mastery significantly mediated some of the relationship between overload and receptor sensitivity (z = -2.02, p = 0.044).Conclusions: These results suggest that a reduced sense of mastery may help explain the association between caregiving burden and reduced immune cell ss2-receptor sensitivity.

Relative Energy Balance, CKD, and Risk of Cardiovascular and All-Cause Mortality.

BACKGROUND Mortality risk for people with chronic kidney disease is substantially greater than that for the general population, increasing to a 7-fold greater risk for those on dialysis therapy. Higher body mass index, generally due to higher energy intake, appears protective for people on dialysis therapy, but the relationship between energy intake and survival in those with reduced kidney function is unknown. STUDY DESIGN Prospective cohort study with a median follow-up of 14.5 (IQR, 11.2-15.2) years. SETTING & PARTICIPANTS Blue Mountains Area, west of Sydney, Australia. Participants in the general community enrolled in the Blue Mountains Eye Study (n=2,664) who underwent a detailed interview, food frequency questionnaire, and physical examination including body weight, height, blood pressure, and laboratory tests. PREDICTORS Relative energy intake, food components (carbohydrates, total sugars, fat, protein, and water), and estimated glomerular filtration rate (eGFR). Relative energy intake was dichotomized at 100%, and eGFR, at 60mL/min/1.73m(2). OUTCOMES All-cause and cardiovascular mortality. MEASUREMENTS All-cause and cardiovascular mortality using unadjusted and adjusted Cox proportional regression models. RESULTS 949 people died during follow-up, 318 of cardiovascular events. In people with eGFR<60mL/min/1.73m(2) (n=852), there was an increased risk of all-cause mortality (HR, 1.48; P=0.03), but no increased risk of cardiovascular mortality (HR, 1.59; P=0.1) among those with higher relative energy intake compared with those with lower relative energy intake. Increasing intake of carbohydrates (HR per 100g/d, 1.50; P=0.04) and total sugars (HR per 100g/d, 1.62; P=0.03) was associated significantly with increased risk of cardiovascular mortality. LIMITATIONS Under-reporting of energy intake, baseline laboratory and food intake values only, white population. CONCLUSIONS Increasing relative energy intake was associated with increased all-cause mortality in patients with eGFR<60mL/min/1.73m(2). This effect may be mediated by increasing total sugars intake on subsequent cardiovascular events.

Antimicrobial drug use and risk factors associated with treatment incidence and mortality in Swiss veal calves reared under improved welfare conditions

Ninety-one Swiss veal farms producing under a label with improved welfare standards were visited between August and December 2014 to investigate risk factors related to antimicrobial drug use and mortality. All herds consisted of own and purchased calves, with a median of 77.4% of purchased calves. The calves' mean age was 29±15days at purchasing and the fattening period lasted at average 120±28 days. The mean carcass weight was 125±12kg. A mean of 58±33 calves were fattened per farm and year, and purchased calves were bought from a mean of 20±17 farms of origin. Antimicrobial drug treatment incidence was calculated with the defined daily dose methodology. The mean treatment incidence (TIADD) was 21±15 daily doses per calf and year. The mean mortality risk was 4.1%, calves died at a mean age of 94±50 days, and the main causes of death were bovine respiratory disease (BRD, 50%) and gastro-intestinal disease (33%). Two multivariable models were constructed, for antimicrobial drug treatment incidence (53 farms) and mortality (91 farms). No quarantine, shared air space for several groups of calves, and no clinical examination upon arrival at the farm were associated with increased antimicrobial treatment incidence. Maximum group size and weight differences >100kg within a group were associated with increased mortality risk, while vaccination and beef breed were associated with decreased mortality risk. The majority of antimicrobial treatments (84.6%) were given as group treatments with oral powder fed through an automatic milk feeding system. Combination products containing chlortetracycline with tylosin and sulfadimidine or with spiramycin were used for 54.9%, and amoxicillin for 43.7% of the oral group treatments. The main indication for individual treatment was BRD (73%). The mean age at the time of treatment was 51 days, corresponding to an estimated weight of 80-100kg. Individual treatments were mainly applied through injections (88.5%), and included administration of fluoroquinolones in 38.3%, penicillines (amoxicillin or benzylpenicillin) in 25.6%, macrolides in 13.1%, tetracyclines in 12.0%, 3th and 4th generation cephalosporines in 4.7%, and florfenicol in 3.9% of the cases. The present study allowed for identifying risk factors for increased antimicrobial drug treatment and mortality. This is an important basis for future studies aiming at reducing treatment incidence and mortality in veal farms. Our results indicate that improvement is needed in the selection of drugs for the treatment of veal calves according to the principles of prudent use of antibiotics.

Clazosentan: prevention of cerebral vasospasm and the potential to overcome infarction

Cerebral vasospasm is a common complication occurring after aneurysmal subarachnoid hemorrhage (SAH). It is recognized as a leading preventable cause of morbidity and mortality in this patient group, but its management is challenging, and new treatments are needed. Clazosentan is an endothelin receptor antagonist designed to prevent endothelin-mediated cerebral vasospasm. Vajkoczy et al. (Neurosurg 103:9-17, 2005) initially demonstrated that clazosentan reduced moderate/severe angiographically proven vasospasm by 55% relative to placebo. These findings led to the initiation of the CONSCIOUS trial program to further examine the efficacy and safety of clazosentan in reducing angiographic vasospasm and improving clinical outcome after aneurysmal SAH. In the first of these studies, CONSCIOUS-1, 413 patients were randomized to placebo or clazosentan 1, 5 or 15 mg/h. Clazosentan reduced angiographic vasospasm dose-dependently relative to placebo with a maximum risk reduction of 65% with the highest dose. Despite this, there was no benefit of clazosentan on the secondary protocol-defined morbidity/mortality endpoint; however, additional post-hoc and modified endpoint analyses provided some evidence for a potential clinical benefit. Two additional large-scale studies (CONSCIOUS-2 and CONSCIOUS-3) are now underway to further investigate the potential of clazosentan to improve long-term clinical outcome.

Prognostic clinical prediction rules to identify a low-risk pulmonary embolism: a systematic review and meta-analysis

Prognostic assessment is important for the management of patients with a pulmonary embolism (PE). A number of clinical prediction rules (CPRs) have been proposed for stratifying PE mortality risk. The aim of this systematic review was to assess the performance of prognostic CPRs in identifying a low-risk PE.