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BACKGROUND - Up-to-date evidence on levels and trends for age-sex-specific all-cause and cause-specific mortality is essential for the formation of global, regional, and national health policies. In the Global Burden of Disease Study 2013 (GBD 2013) we estimated yearly deaths for 188 countries between 1990, and 2013. We used the results to assess whether there is epidemiological convergence across countries.
METHODS - We estimated age-sex-specific all-cause mortality using the GBD 2010 methods with some refinements to improve accuracy applied to an updated database of vital registration, survey, and census data. We generally estimated cause of death as in the GBD 2010. Key improvements included the addition of more recent vital registration data for 72 countries, an updated verbal autopsy literature review, two new and detailed data systems for China, and more detail for Mexico, UK, Turkey, and Russia. We improved statistical models for garbage code redistribution. We used six different modelling strategies across the 240 causes; cause of death ensemble modelling (CODEm) was the dominant strategy for causes with sufficient information. Trends for Alzheimer's disease and other dementias were informed by meta-regression of prevalence studies. For pathogen-specific causes of diarrhoea and lower respiratory infections we used a counterfactual approach. We computed two measures of convergence (inequality) across countries: the average relative difference across all pairs of countries (Gini coefficient) and the average absolute difference across countries. To summarise broad findings, we used multiple decrement life-tables to decompose probabilities of death from birth to exact age 15 years, from exact age 15 years to exact age 50 years, and from exact age 50 years to exact age 75 years, and life expectancy at birth into major causes. For all quantities reported, we computed 95% uncertainty intervals (UIs). We constrained cause-specific fractions within each age-sex-country-year group to sum to all-cause mortality based on draws from the uncertainty distributions.
FINDINGS - Global life expectancy for both sexes increased from 65.3 years (UI 65.0-65.6) in 1990, to 71.5 years (UI 71.0-71.9) in 2013, while the number of deaths increased from 47.5 million (UI 46.8-48.2) to 54.9 million (UI 53.6-56.3) over the same interval. Global progress masked variation by age and sex: for children, average absolute differences between countries decreased but relative differences increased. For women aged 25-39 years and older than 75 years and for men aged 20-49 years and 65 years and older, both absolute and relative differences increased. Decomposition of global and regional life expectancy showed the prominent role of reductions in age-standardised death rates for cardiovascular diseases and cancers in high-income regions, and reductions in child deaths from diarrhoea, lower respiratory infections, and neonatal causes in low-income regions. HIV/AIDS reduced life expectancy in southern sub-Saharan Africa. For most communicable causes of death both numbers of deaths and age-standardised death rates fell whereas for most non-communicable causes, demographic shifts have increased numbers of deaths but decreased age-standardised death rates. Global deaths from injury increased by 10.7%, from 4.3 million deaths in 1990 to 4.8 million in 2013; but age-standardised rates declined over the same period by 21%. For some causes of more than 100,000 deaths per year in 2013, age-standardised death rates increased between 1990 and 2013, including HIV/AIDS, pancreatic cancer, atrial fibrillation and flutter, drug use disorders, diabetes, chronic kidney disease, and sickle-cell anaemias. Diarrhoeal diseases, lower respiratory infections, neonatal causes, and malaria are still in the top five causes of death in children younger than 5 years. The most important pathogens are rotavirus for diarrhoea and pneumococcus for lower respiratory infections. Country-specific probabilities of death over three phases of life were substantially varied between and within regions.
INTERPRETATION - For most countries, the general pattern of reductions in age-sex specific mortality has been associated with a progressive shift towards a larger share of the remaining deaths caused by non-communicable disease and injuries. Assessing epidemiological convergence across countries depends on whether an absolute or relative measure of inequality is used. Nevertheless, age-standardised death rates for seven substantial causes are increasing, suggesting the potential for reversals in some countries. Important gaps exist in the empirical data for cause of death estimates for some countries; for example, no national data for India are available for the past decade.
FUNDING - Bill & Melinda Gates Foundation.
Copyright © 2015 Elsevier Ltd. All rights reserved.

BACKGROUND - Combination antiretroviral therapy (ART) has significantly increased survival among HIV-positive adults in the United States (U.S.) and Canada, but gains in life expectancy for this region have not been well characterized. We aim to estimate temporal changes in life expectancy among HIV-positive adults on ART from 2000-2007 in the U.S. and Canada.
METHODS - Participants were from the North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD), aged ≥20 years and on ART. Mortality rates were calculated using participants' person-time from January 1, 2000 or ART initiation until death, loss to follow-up, or administrative censoring December 31, 2007. Life expectancy at age 20, defined as the average number of additional years that a person of a specific age will live, provided the current age-specific mortality rates remain constant, was estimated using abridged life tables.
RESULTS - The crude mortality rate was 19.8/1,000 person-years, among 22,937 individuals contributing 82,022 person-years and 1,622 deaths. Life expectancy increased from 36.1 [standard error (SE) 0.5] to 51.4 [SE 0.5] years from 2000-2002 to 2006-2007. Men and women had comparable life expectancies in all periods except the last (2006-2007). Life expectancy was lower for individuals with a history of injection drug use, non-whites, and in patients with baseline CD4 counts <350 cells/mm(3).
CONCLUSIONS - A 20-year-old HIV-positive adult on ART in the U.S. or Canada is expected to live into their early 70 s, a life expectancy approaching that of the general population. Differences by sex, race, HIV transmission risk group, and CD4 count remain.

The advent of effective combination antiretroviral therapy (ART) in 1996 resulted in fewer patients experiencing clinical events, so that some prognostic analyses of individual cohort studies of human immunodeficiency virus-infected individuals had low statistical power. Because of this, the Antiretroviral Therapy Cohort Collaboration (ART-CC) of HIV cohort studies in Europe and North America was established in 2000, with the aim of studying the prognosis for clinical events in acquired immune deficiency syndrome (AIDS) and the mortality of adult patients treated for HIV-1 infection. In 2002, the ART-CC collected data on more than 12,000 patients in 13 cohorts who had begun combination ART between 1995 and 2001. Subsequent updates took place in 2004, 2006, 2008, and 2010. The ART-CC data base now includes data on more than 70,000 patients participating in 19 cohorts who began treatment before the end of 2009. Data are collected on patient demographics (e.g. sex, age, assumed transmission group, race/ethnicity, geographical origin), HIV biomarkers (e.g. CD4 cell count, plasma viral load of HIV-1), ART regimen, dates and types of AIDS events, and dates and causes of death. In recent years, additional data on co-infections such as hepatitis C; risk factors such as smoking, alcohol and drug use; non-HIV biomarkers such as haemoglobin and liver enzymes; and adherence to ART have been collected whenever available. The data remain the property of the contributing cohorts, whose representatives manage the ART-CC via the steering committee of the Collaboration. External collaboration is welcomed. Details of contacts are given on the ART-CC website (www.art-cohort-collaboration.org).
Published by Oxford University Press on behalf of the International Epidemiological Association © The Author 2013; all rights reserved.

BACKGROUND - Acute kidney injury (AKI) is common after cardiac surgery, and expeditious recognition with specific biomarkers may help improve outcome.
OBJECTIVE - Because the economic impact of a biomarker-based diagnostic strategy is unknown, we assessed the cost-effectiveness of using urinary neutrophil gelatinase-associated lipocalin (NGAL) for the diagnosis of AKI after cardiac surgery compared with current diagnostic methods.
METHODS - A decision analysis model was developed using the societal perspective to evaluate the cost-effectiveness of NGAL. Cost per quality-adjusted life-year (QALY) was determined for NGAL and standard strategies. The base case was a 67-year-old male patient undergoing coronary artery bypass graft surgery in the United Kingdom. Multiple sensitivity analyses were performed to determine how cost-effectiveness would vary with changes in the underlying clinical and economic variables.
RESULTS - The base case yielded expected costs of £4244 and 11.86 QALYs for the NGAL strategy compared with £4672 and 11.79 QALYs for the standard therapy. The cost-effectiveness ratio for the NGAL strategy was £358/QALY compared with £396/QALY for the standard regimen. Cost-effectiveness increased as the treatment effect-defined as the ability to prevent progression of established AKI (kidney injury or failure)-for the therapy triggered by an elevated NGAL level rose. Sensitivity analysis demonstrated that the model was most responsive to the probability of developing AKI and least sensitive to the test cost for NGAL. Probabilistic sensitivity analysis supported the NGAL strategy as the most cost-effective option. Because this study was a decision analysis model incorporating a nonspecific treatment for AKI (as opposed to an observational study or controlled trial), model structural assumptions may therefore have underestimated mortality and the likelihood of developing AKI, although these were tested in multiple sensitivity analyses. Indirect costs were also not explicitly factored.
CONCLUSION - The use of urinary NGAL after cardiac surgery appears to be cost-effective in the early diagnosis of AKI.
Copyright © 2011 Elsevier HS Journals, Inc. All rights reserved.

Although attentional control and memory change considerably across the life span, no research has examined how the ability to strategically remember important information (i.e., value-directed remembering) changes from childhood to old age. The present study examined this in different age groups across the life span (N = 320, 5-96 years old). A selectivity task was used in which participants were asked to study and recall items worth different point values in order to maximize their point score. This procedure allowed for measures of memory quantity/capacity (number of words recalled) and memory efficiency/selectivity (the recall of high-value items relative to low-value items). Age-related differences were found for memory capacity, as young adults recalled more words than the other groups. However, in terms of selectivity, younger and older adults were more selective than adolescents and children. The dissociation between these measures across the life span illustrates important age-related differences in terms of memory capacity and the ability to selectively remember high-value information.

The dramatic increase during the past decade in prostate-specific antigen (PSA) testing and prostate biopsies has resulted in the detection of large numbers of small lesions, an increase in the incidence of prostate cancer, and an increasing incidence-to-mortality ratio. Currently, the risk of being diagnosed with prostate cancer is increasingly greater than the risk of dying of it. The currently available treatments for prostate cancer are not well suited to treating small or indolent tumors. Radical treatment, whether surgery or radiotherapy, can eradicate cancer effectively, but these techniques, as well as hormonal manipulations, can have adverse effects on patients' health and quality of life. Watchful waiting, or "active surveillance," has the advantage of avoiding the deleterious effects on quality of life, but it confronts patients with the emotional burden of living with an untreated cancer that could progress and metastasize. For active surveillance, no established, objective criteria are available for progression that would signal the optimal time for therapeutic intervention. PSA levels in patients with low-risk, small-volume cancers are more indicative of the size of the benign prostate or the presence of inflammation than of changes in the volume or growth of the cancer, and PSA levels inherently fluctuate, creating a low signal-to-noise ratio until the cancer is very large. Little risk exists in waiting to confirm a sustained increase in the PSA level before proceeding with a diagnostic biopsy. This policy would decrease the number of unnecessary biopsies, but still diagnose men within a safe timeframe. In studies controlled for age and comorbidity, the survival rate for patients with low-risk prostate cancer mirrors that expected in the general population. This holds true across cohorts of patients, whatever the treatment used. Because no strong medical or scientific evidence supports any particular ablative technique for low-risk prostate cancer, no standard of care has been universally accepted. Therefore, practice patterns are heterogeneous and depend more on the availability of treatments than on the features of the disease itself.

Treatment choices for metastatic prostate cancer are complex and can involve men balancing survival versus quality of life. The present study aims to elicit patient preferences with respect to the attributes of treatments for metastatic prostate cancer through a discrete choice experiment (DCE) questionnaire. Men with recently diagnosed localized prostate cancer were asked to envisage that they had metastatic disease when completing a survey. As expected, men with prostate cancer placed considerable importance on gains in survival; however, avoiding side effects of treatment was also clearly important. Survival gains should be considered alongside side effects when discussing treatment options in metastatic disease.