Worldwide prevalence of anaemia, WHO Vitamin and Mineral Nutrition Information System, 1993-2005

Abstract Objective To provide current global and regional estimates of anaemia prevalence and number of persons affected in the total population and by population subgroup. Setting and design We used anaemia prevalence data from the WHO Vitamin and Mineral Nutrition Information System for 1993-2005 to generate anaemia prevalence estimates for countries with data representative at the national level or at the first administrative level that is below the national level. For countries without eligible data, we employed regression-based estimates, which used the UN Human Development Index (HDI) and other health indicators. We combined country estimates, weighted by their population, to estimate anaemia prevalence at the global level, by UN Regions and by category of human development. Results Survey data covered 48·8 % of the global population, 76·1 % of preschool-aged children, 69·0 % of pregnant women and 73·5 % of non-pregnant women. The estimated global anaemia prevalence is 24·8 % (95 % CI 22·9, 26·7 %), affecting 1·62 billion people (95 % CI 1·50, 1·74 billion). Estimated anaemia prevalence is 47·4 % (95 % CI 45·7, 49·1 %) in preschool-aged children, 41·8 % (95 % CI 39·9, 43·8 %) in pregnant women and 30·2 % (95 % CI 28·7, 31·6 %) in non-pregnant women. In numbers, 293 million (95 % CI 282, 303 million) preschool-aged children, 56 million (95 % CI 54, 59 million) pregnant women and 468 million (95 % CI 446, 491 million) non-pregnant women are affected. Conclusion Anaemia affects one-quarter of the world's population and is concentrated in preschool-aged children and women, making it a global public health problem. Data on relative contributions of causal factors are lacking, however, which makes it difficult to effectively address the proble

Improving Event Time Prediction by Learning to Partition the Event Time Space

Recently developed survival analysis methods improve upon existing approaches by predicting the probability of event occurrence in each of a number pre-specified (discrete) time intervals. By avoiding placing strong parametric assumptions on the event density, this approach tends to improve prediction performance, particularly when data are plentiful. However, in clinical settings with limited available data, it is often preferable to judiciously partition the event time space into a limited number of intervals well suited to the prediction task at hand. In this work, we develop a method to learn from data a set of cut points defining such a partition. We show that in two simulated datasets, we are able to recover intervals that match the underlying generative model. We then demonstrate improved prediction performance on three real-world observational datasets, including a large, newly harmonized stroke risk prediction dataset. Finally, we argue that our approach facilitates clinical decision-making by suggesting time intervals that are most appropriate for each task, in the sense that they facilitate more accurate risk prediction.Comment: 16 pages, 5 figures, 2 table

Heart Rate or Beta-Blocker Dose? Association With Outcomes in Ambulatory Heart Failure Patients With Systolic Dysfunction Results From the HF-ACTION Trial

AbstractObjectivesThis study aimed to compare whether reduced heart rate (HR) or higher beta-blocker (BB) dose affected outcomes to a greater extent in the HF-ACTION (Heart Failure: A Controlled Trial Investigating Outcomes of Exercise Training) trial population.BackgroundRecent data have shown that HR is an important modifiable factor in reducing mortality in heart failure (HF) patients. It has also been shown that titration of doses of BBs improves outcomes of morbidity and mortality in chronic HF patients with reduced ejection fraction. We aimed to compare whether reduced HR or higher BB dose affected outcomes to a greater extent in the HF-ACTION trial population.MethodsHF-ACTION was a randomized, multicenter trial enrolling 2,331 ambulatory HF patients with systolic dysfunction (New York Heart Association functional class II to IV, left ventricular ejection fraction <0.35) randomized to exercise training versus usual care, with median follow-up of 2.5 years. BB dose at baseline was standardized by use of carvedilol equivalents. BB dose and HR were analyzed by discrete groups (higher/lower dose; higher/lower HR). The relationship of BB dose, HR, and the primary endpoint of all-cause mortality or all-cause hospitalization and other cardiovascular secondary endpoints were determined before and after adjustment for variables found to be significantly associated with outcome in the HF-ACTION cohort.ResultsThere was a significant inverse relationship between either BB dose (higher was better) or HR (lower was better) and all-cause death or hospitalization in unadjusted analysis; however, only BB dose was significant for improved mortality outcomes. After adjustment for other predictors of outcome, only BB dose remained significant for improving all-cause death or hospitalization. BB dose, but not HR, was associated with improved outcomes of other cardiovascular endpoints in unadjusted analysis but did not remain significant when adjusted for other predictors of outcome in this cohort.ConclusionsThere were more associated improvements in outcomes with higher BB dose than with reduced HR in this well-treated HF cohort with systolic dysfunction, which suggests that titration of BB doses may confer a greater benefit than reduction of HR in such patients. (Heart Failure: A Controlled Trial Investigating Outcomes of Exercise Training [HF-ACTION]; NCT00047437

Prospective relationships between body weight and physical activity: an observational analysis from the NAVIGATOR study

Objectives: While bidirectional relationships exist between body weight and physical activity, direction of causality remains uncertain and previous studies have been limited by self-reported activity or weight and small sample size. We investigated the prospective relationships between weight and physical activity. Design: Observational analysis of data from the Nateglinide And Valsartan in Impaired Glucose Tolerance Outcomes Research (NAVIGATOR) study, a double-blinded randomised clinical trial of nateglinide and valsartan, respectively. Setting Multinational study of 9306 participants. Participants: Participants with biochemically confirmed impaired glucose tolerance had annual measurements of both weight and step count using research grade pedometers, worn for 7 days consecutively. Along with randomisation to valsartan or placebo plus nateglinide or placebo, participants took part in a lifestyle modification programme. Outcome measures: Longitudinal regression using weight as response value and physical activity as predictor value was conducted, adjusted for baseline covariates. Analysis was then repeated with physical activity as response value and weight as predictor value. Only participants with a response value preceded by at least three annual response values were included. Results: Adequate data were available for 2811 (30%) of NAVIGATOR participants. Previous weight (χ2=16.8; p&lt;0.0001), but not change in weight (χ2=0.1; p=0.71) was inversely associated with subsequent step count, indicating lower subsequent levels of physical activity in heavier individuals. Change in step count (χ2=5.9; p=0.02) but not previous step count (χ2=0.9; p=0.34) was inversely associated with subsequent weight. However, in the context of trajectories already established for weight (χ2 for previous weight measurements 747.3; p&lt;0.0001) and physical activity (χ2 for previous step count 432.6; p&lt;0.0001), these effects were of limited clinical importance. Conclusions: While a prospective bidirectional relationship was observed between weight and physical activity, the magnitude of any effect was very small in the context of natural trajectories already established for these variables

Relationship of Beta-Blocker Dose With Outcomes in Ambulatory Heart Failure Patients With Systolic Dysfunction Results From the HF-ACTION (Heart Failure: A Controlled Trial Investigating Outcomes of Exercise Training) Trial

ObjectivesThis study sought to examine the association between baseline beta-blocker (BB) dose and outcomes in the HF-ACTION (Heart Failure: A Controlled Trial Investigating Outcomes of Exercise Training) trial.BackgroundBeta-blockers reduce morbidity and mortality in chronic heart failure (HF) patients with reduced ejection fraction, but it is unclear whether titrating to higher BB doses improves outcomes in this setting.MethodsThe HF-ACTION trial was a randomized, multicenter trial enrolling 2,331 ambulatory HF patients with systolic dysfunction (New York Heart Association functional class II to IV, left ventricular ejection fraction <0.35) randomized to exercise training versus usual care, with median follow-up of 2.5 years. The BB dose at baseline was standardized with carvedilol equivalents and analyzed as a continuous variable and by discrete dose groups. The relationship between BB dose and the primary endpoint of all-cause mortality or all-cause hospitalization and other cardiovascular secondary endpoints was determined before and after adjustment for variables significantly associated with outcomes in the HF-ACTION cohort.ResultsNinety-five percent of patients were receiving a BB. There was a significant inverse relationship between BB dose and all-cause death or hospitalization but not other cardiovascular endpoints after adjustment for other predictors of outcome, with a linear benefit up to the 50-mg daily dose. There was a significant association between BB dose and change in peak VO2 at 3 months. There was no increase in bradycardia with higher doses of BB.ConclusionsThere was a significant inverse relationship between BB dose and the endpoint of all-cause death or all-cause hospitalization in this well-treated HF cohort with systolic dysfunction, supporting recommendations that titrating doses up to 50 mg/day might confer a benefit in such patients. (Exercise Training Program to Improve Clinical Outcomes in Individuals With Congestive Heart Failure; NCT00047437

National estimates for maternal mortality: an analysis based on the WHO systematic review of maternal mortality and morbidity

BACKGROUND: Despite the worldwide commitment to improving maternal health, measuring, monitoring and comparing maternal mortality estimates remain a challenge. Due to lack of data, international agencies have to rely on mathematical models to assess its global burden. In order to assist in mapping the burden of reproductive ill-health, we conducted a systematic review of incidence/prevalence of maternal mortality and morbidity. METHODS: We followed the standard methodology for systematic reviews. This manuscript presents nationally representative estimates of maternal mortality derived from the systematic review. Using regression models, relationships between study-specific and country-specific variables with the maternal mortality estimates are explored in order to assist further modelling to predict maternal mortality. RESULTS: Maternal mortality estimates included 141 countries and represent 78.1% of the live births worldwide. As expected, large variability between countries, and within regions and subregions, is identified. Analysis of variability according to study characteristics did not yield useful results given the high correlation with each other, with development status and region. A regression model including selected country-specific variables was able to explain 90% of the variability of the maternal mortality estimates. Among all country-specific variables selected for the analysis, three had the strongest relationships with maternal mortality: proportion of deliveries assisted by a skilled birth attendant, infant mortality rate and health expenditure per capita. CONCLUSION: With the exception of developed countries, variability of national maternal mortality estimates is large even within subregions. It seems more appropriate to study such variation through differentials in other national and subnational characteristics. Other than region, study of country-specific variables suggests infant mortality rate, skilled birth attendant at delivery and health expenditure per capita are key variables to predict maternal mortality at national level

Left ventricular systolic dysfunction, heart failure, and the risk of stroke and systemic embolism in patients with atrial fibrillation : insights from the ARISTOTLE trial

We examined the risk of stroke or systemic embolism (SSE) conferred by heart failure (HF) and left ventricular systolic dysfunction (LVSD) in the Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation Trial (ARISTOTLE), as well as the effect of apixaban versus warfarin

Технология получения сухого экстракта листьев малины обыкновенной

ТЕХНОЛОГИЯ ФАРМАЦЕВТИЧЕСКАЯРАСТИТЕЛЬНОЕ СЫРЬЕСУШКА РАСТЕНИЙРАСТЕНИЯ ЛЕКАРСТВЕННЫЕТРАВЫ ЛЕКАРСТВЕННЫЕРАСТЕНИЙ ЭКСТРАКТЫМАЛИНАRUBUS IDAEUS L.РАСТЕНИЙ ЛИСТЬЯРЕПЕРКОЛЯЦИЯДУБИЛЬНЫЕ ВЕЩЕСТВ