Global, regional, and national under-5 mortality, adult mortality, age-specific mortality, and life expectancy, 1970–2016: a systematic analysis for the Global Burden of Disease Study 2016

BACKGROUND: Detailed assessments of mortality patterns, particularly age-specific mortality, represent a crucial input that enables health systems to target interventions to specific populations. Understanding how all-cause mortality has changed with respect to development status can identify exemplars for best practice. To accomplish this, the Global Burden of Diseases, Injuries, and Risk Factors Study 2016 (GBD 2016) estimated age-specific and sex-specific all-cause mortality between 1970 and 2016 for 195 countries and territories and at the subnational level for the five countries with a population greater than 200 million in 2016. METHODS: We have evaluated how well civil registration systems captured deaths using a set of demographic methods called death distribution methods for adults and from consideration of survey and census data for children younger than 5 years. We generated an overall assessment of completeness of registration of deaths by dividing registered deaths in each location-year by our estimate of all-age deaths generated from our overall estimation process. For 163 locations, including subnational units in countries with a population greater than 200 million with complete vital registration (VR) systems, our estimates were largely driven by the observed data, with corrections for small fluctuations in numbers and estimation for recent years where there were lags in data reporting (lags were variable by location, generally between 1 year and 6 years). For other locations, we took advantage of different data sources available to measure under-5 mortality rates (U5MR) using complete birth histories, summary birth histories, and incomplete VR with adjustments; we measured adult mortality rate (the probability of death in individuals aged 15-60 years) using adjusted incomplete VR, sibling histories, and household death recall. We used the U5MR and adult mortality rate, together with crude death rate due to HIV in the GBD model life table system, to estimate age-specific and sex-specific death rates for each location-year. Using various international databases, we identified fatal discontinuities, which we defined as increases in the death rate of more than one death per million, resulting from conflict and terrorism, natural disasters, major transport or technological accidents, and a subset of epidemic infectious diseases; these were added to estimates in the relevant years. In 47 countries with an identified peak adult prevalence for HIV/AIDS of more than 0·5% and where VR systems were less than 65% complete, we informed our estimates of age-sex-specific mortality using the Estimation and Projection Package (EPP)-Spectrum model fitted to national HIV/AIDS prevalence surveys and antenatal clinic serosurveillance systems. We estimated stillbirths, early neonatal, late neonatal, and childhood mortality using both survey and VR data in spatiotemporal Gaussian process regression models. We estimated abridged life tables for all location-years using age-specific death rates. We grouped locations into development quintiles based on the Socio-demographic Index (SDI) and analysed mortality trends by quintile. Using spline regression, we estimated the expected mortality rate for each age-sex group as a function of SDI. We identified countries with higher life expectancy than expected by comparing observed life expectancy to anticipated life expectancy on the basis of development status alone. FINDINGS: Completeness in the registration of deaths increased from 28% in 1970 to a peak of 45% in 2013; completeness was lower after 2013 because of lags in reporting. Total deaths in children younger than 5 years decreased from 1970 to 2016, and slower decreases occurred at ages 5-24 years. By contrast, numbers of adult deaths increased in each 5-year age bracket above the age of 25 years. The distribution of annualised rates of change in age-specific mortality rate differed over the period 2000 to 2016 compared with earlier decades: increasing annualised rates of change were less frequent, although rising annualised rates of change still occurred in some locations, particularly for adolescent and younger adult age groups. Rates of stillbirths and under-5 mortality both decreased globally from 1970. Evidence for global convergence of death rates was mixed; although the absolute difference between age-standardised death rates narrowed between countries at the lowest and highest levels of SDI, the ratio of these death rates-a measure of relative inequality-increased slightly. There was a strong shift between 1970 and 2016 toward higher life expectancy, most noticeably at higher levels of SDI. Among countries with populations greater than 1 million in 2016, life expectancy at birth was highest for women in Japan, at 86·9 years (95% UI 86·7-87·2), and for men in Singapore, at 81·3 years (78·8-83·7) in 2016. Male life expectancy was generally lower than female life expectancy between 1970 and 2016, an

Global, regional, and national incidence, prevalence, and years lived with disability for 354 diseases and injuries for 195 countries and territories, 1990-2017: a systematic analysis for the Global Burden of Disease Study 2017.

The Global Burden of Diseases, Injuries and Risk Factors 2017 includes a comprehensive assessment of incidence, prevalence, and years lived with disability (YLDs) for 354 causes in 195 countries and territories from 1990 to 2017. Previous GBD studies have shown how the decline of mortality rates from 1990 to 2016 has led to an increase in life expectancy, an ageing global population, and an expansion of the non-fatal burden of disease and injury. These studies have also shown how a substantial portion of the world's population experiences non-fatal health loss with considerable heterogeneity among different causes, locations, ages, and sexes. Ongoing objectives of the GBD study include increasing the level of estimation detail, improving analytical strategies, and increasing the amount of high-quality data. METHODS: We estimated incidence and prevalence for 354 diseases and injuries and 3484 sequelae. We used an updated and extensive body of literature studies, survey data, surveillance data, inpatient admission records, outpatient visit records, and health insurance claims, and additionally used results from cause of death models to inform estimates using a total of 68 781 data sources. Newly available clinical data from India, Iran, Japan, Jordan, Nepal, China, Brazil, Norway, and Italy were incorporated, as well as updated claims data from the USA and new claims data from Taiwan (province of China) and Singapore. We used DisMod-MR 2.1, a Bayesian meta-regression tool, as the main method of estimation, ensuring consistency between rates of incidence, prevalence, remission, and cause of death for each condition. YLDs were estimated as the product of a prevalence estimate and a disability weight for health states of each mutually exclusive sequela, adjusted for comorbidity. We updated the Socio-demographic Index (SDI), a summary development indicator of income per capita, years of schooling, and total fertility rate. Additionally, we calculated differences between male and female YLDs to identify divergent trends across sexes. GBD 2017 complies with the Guidelines for Accurate and Transparent Health Estimates Reporting

Global, regional, and national incidence, prevalence, and years lived with disability for 354 diseases and injuries for 195 countries and territories, 1990-2017: a systematic analysis for the Global Burden of Disease Study 2017

The Global Burden of Diseases, Injuries, and Risk Factors Study 2017 (GBD 2017) includes a comprehensive assessment of incidence, prevalence, and years lived with disability (YLDs) for 354 causes in 195 countries and territories from 1990 to 2017. Previous GBD studies have shown how the decline of mortality rates from 1990 to 2016 has led to an increase in life expectancy, an ageing global population, and an expansion of the non-fatal burden of disease and injury. These studies have also shown how a substantial portion of the world's population experiences non-fatal health loss with considerable heterogeneity among different causes, locations, ages, and sexes. Ongoing objectives of the GBD study include increasing the level of estimation detail, improving analytical strategies, and increasing the amount of high-quality data.; We estimated incidence and prevalence for 354 diseases and injuries and 3484 sequelae. We used an updated and extensive body of literature studies, survey data, surveillance data, inpatient admission records, outpatient visit records, and health insurance claims, and additionally used results from cause of death models to inform estimates using a total of 68 781 data sources. Newly available clinical data from India, Iran, Japan, Jordan, Nepal, China, Brazil, Norway, and Italy were incorporated, as well as updated claims data from the USA and new claims data from Taiwan (province of China) and Singapore. We used DisMod-MR 2.1, a Bayesian meta-regression tool, as the main method of estimation, ensuring consistency between rates of incidence, prevalence, remission, and cause of death for each condition. YLDs were estimated as the product of a prevalence estimate and a disability weight for health states of each mutually exclusive sequela, adjusted for comorbidity. We updated the Socio-demographic Index (SDI), a summary development indicator of income per capita, years of schooling, and total fertility rate. Additionally, we calculated differences between male and female YLDs to identify divergent trends across sexes. GBD 2017 complies with the Guidelines for Accurate and Transparent Health Estimates Reporting. Globally, for females, the causes with the greatest age-standardised prevalence were oral disorders, headache disorders, and haemoglobinopathies and haemolytic anaemias in both 1990 and 2017. For males, the causes with the greatest age-standardised prevalence were oral disorders, headache disorders, and tuberculosis including latent tuberculosis infection in both 1990 and 2017. In terms of YLDs, low back pain, headache disorders, and dietary iron deficiency were the leading Level 3 causes of YLD counts in 1990, whereas low back pain, headache disorders, and depressive disorders were the leading causes in 2017 for both sexes combined. All-cause age-standardised YLD rates decreased by 3·9% (95% uncertainty interval [UI] 3·1-4·6) from 1990 to 2017; however, the all-age YLD rate increased by 7·2% (6·0-8·4) while the total sum of global YLDs increased from 562 million (421-723) to 853 million (642-1100). The increases for males and females were similar, with increases in all-age YLD rates of 7·9% (6·6-9·2) for males and 6·5% (5·4-7·7) for females. We found significant differences between males and females in terms of age-standardised prevalence estimates for multiple causes. The causes with the greatest relative differences between sexes in 2017 included substance use disorders (3018 cases [95% UI 2782-3252] per 100 000 in males vs s1400 [1279-1524] per 100 000 in females), transport injuries (3322 [3082-3583] vs 2336 [2154-2535]), and self-harm and interpersonal violence (3265 [2943-3630] vs 5643 [5057-6302]). Global all-cause age-standardised YLD rates have improved only slightly over a period spanning nearly three decades. However, the magnitude of the non-fatal disease burden has expanded globally, with increasing numbers of people who have a wide spectrum of conditions. A subset of conditions has remained globally pervasive since 1990, whereas other conditions have displayed more dynamic trends, with different ages, sexes, and geographies across the globe experiencing varying burdens and trends of health loss. This study emphasises how global improvements in premature mortality for select conditions have led to older populations with complex and potentially expensive diseases, yet also highlights global achievements in certain domains of disease and injury

Global, regional, and national age-sex-specific mortality for 282 causes of death in 195 countries and territories, 1980-2017: a systematic analysis for the Global Burden of Disease Study 2017.

BACKGROUND: Global development goals increasingly rely on country-specific estimates for benchmarking a nation's progress. To meet this need, the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2016 estimated global, regional, national, and, for selected locations, subnational cause-specific mortality beginning in the year 1980. Here we report an update to that study, making use of newly available data and improved methods. GBD 2017 provides a comprehensive assessment of cause-specific mortality for 282 causes in 195 countries and territories from 1980 to 2017. METHODS: The causes of death database is composed of vital registration (VR), verbal autopsy (VA), registry, survey, police, and surveillance data. GBD 2017 added ten VA studies, 127 country-years of VR data, 502 cancer-registry country-years, and an additional surveillance country-year. Expansions of the GBD cause of death hierarchy resulted in 18 additional causes estimated for GBD 2017. Newly available data led to subnational estimates for five additional countries-Ethiopia, Iran, New Zealand, Norway, and Russia. Deaths assigned International Classification of Diseases (ICD) codes for non-specific, implausible, or intermediate causes of death were reassigned to underlying causes by redistribution algorithms that were incorporated into uncertainty estimation. We used statistical modelling tools developed for GBD, including the Cause of Death Ensemble model (CODEm), to generate cause fractions and cause-specific death rates for each location, year, age, and sex. Instead of using UN estimates as in previous versions, GBD 2017 independently estimated population size and fertility rate for all locations. Years of life lost (YLLs) were then calculated as the sum of each death multiplied by the standard life expectancy at each age. All rates reported here are age-standardised

Tacticity effects on conformational structure and hydration of poly-(methacrylic acid) in aqueous solutions-a molecular dynamics simulation study

<p>The influence of tacticity on chain dimensions, backbone and side-group conformational states and relaxation dynamics, intermolecular hydrogen bonding and its relaxation dynamics was investigated for 30 repeat unit poly(methacrylic acid) (PMA) as a function of the degree-of-neutralisation, <i>f</i> (i.e. charge density) [0 < <i>f</i> < 1 range] in explicit water with Na⁺ neutralising counter-ions, using molecular dynamics simulations. Chain expansion with increase in charge density is observed. Simulation results, where applicable, compare well with experimental results in the literature. <i>Isotactic</i> (<i>i</i>-PMA) chain exhibits the largest expansion (89% change in <i>R</i>_<i>g</i>), and <i>syndiotactic</i> (<i>s</i>-PMA-RR-0.7) chain shows 31%. For fully neutralised chain (high charge density), the probability for <i>trans</i> conformation at backbone bonds follows the trend <i>i</i>-PMA > <i>a</i>-PMA > <i>s</i>-PMA. At high charge density, a higher probability of <i>trans</i> state is obtained at <i>meso dyads</i> as compared to <i>racemic dyads</i> and the side group in <i>i</i>-PMA relative to other tacticity is conformationally more extended. RR <i>triads</i> impart better hydrogen bonding with water. In the COOH side group, greater rotational mobility is observed for <i>i</i>-PMA as compared to <i>s</i>-PMA. Water coordination to PMA is invariant with tacticity at low <i>f</i>. For <i>f</i> = 1, <i>s</i>-PMA exhibits the best level of H-bonding, due to its 3D chemical structural configuration. Binding distance between water and PMA atoms and their coordination number remain unchanged with respect to ionisation of COOH groups. <i>Isotactic</i> (<i>i</i>-PMA) exhibits the fastest relaxation of polymer-water H-bonds. While counter-ion coordination on to PMA is unaffected by tacticity, the intensity of ion condensation as well as hydrogen bond relaxation time at <i>f</i> = 1 varies in the order <i>i</i>-PMA > <i>a</i>-PMA > <i>s</i>-PMA.</p

Self-association behaviour of <i>atactic</i> polymethacrylic acid in aqueous solution investigated by atomistic molecular dynamics simulations

<div><p>The self-association behaviour of <i>atactic</i> poly(methacrylic acid) (<i>a</i>-PMA) in water was investigated by atomistic molecular dynamics (MD) simulations. Simulations show that interchain association of <i>a</i>-PMA occurs only in its un-neutralised form, by hydrogen bonding between –COOH groups, which is in agreement with the experimental observation. Chain conformations, dihedral angle distributions, hydration behaviour, scattering structure factor and enthalpy-of-hydration (i.e. aqueous solvation) were analysed as a function of concentration for un-neutralised PMA, across dilute to concentrated regimes. The average 〈<i>R</i>_g〉 of the chain remains unaffected in solution and also for amorphous undissolved <i>a</i>-PMA phase, confirming the occurrence of the approximate <i>theta</i>-solution condition for the first time, as revealed by simulations, in a polar hydrogen-bonding polymer aqueous solution. Chain hydration behaviour and scattering structure factor show significant changes in concentrated regime. Scattering intensity collapse occurs in concentrated PMA solution, due to the existence of the swollen regime captured for the first time by explicit-MD-simulations. The hydration of PMA is driven by H-bonding, specifically between H atoms of the COOH groups and O atoms of water molecules in the closest coordination shell. The enthalpy of hydration of PMA is dominated by PMA–water interactions (charges and H-bonding). The thermodynamic contributions of PMA–PMA and PMA–water interactions towards the electrostatics as well as the dispersion components of the total solvation-enthalpy become more favourable than water–water interactions.</p></div

Molecular Dynamics Simulations of Adsorption of Poly(acrylic acid) and Poly(methacrylic acid) on Dodecyltrimethylammonium Chloride Micelle in Water: Effect of Charge Density

We have investigated the interaction of dodecyltrimethylammonium chloride (DoTA) micelle with weak polyelectrolytes, poly­(acrylic acid) and poly­(methacrylic acid). Anionic as well as un-ionized forms of the polyelectrolytes were studied. Polyelectrolyte–surfactant complexes were formed within 5–11 ns of the simulation time and were found to be stable. Association is driven purely by electrostatic interactions for anionic chains whereas dispersion interactions also play a dominant role in the case of un-ionized chains. Surfactant headgroup nitrogen atoms are in close contact with the carboxylic oxygens of the polyelectrolyte chain at a distance of 0.35 nm. In the complexes, the polyelectrolyte chains are adsorbed on to the hydrophilic micellar surface and do not penetrate into the hydrophobic core of the micelle. Polyacrylate chain shows higher affinity for complex formation with DoTA as compared to polymethacrylate chain. Anionic polyelectrolyte chains show higher interaction strength as compared to corresponding un-ionized chains. Anionic chains act as polymeric counterion in the complexes, resulting in the displacement of counterions (Na⁺ and Cl^–) into the bulk solution. Anionic chains show distinct shrinkage upon adsorption onto the micelle. Detailed information about the microscopic structure and binding characteristics of these complexes is in agreement with available experimental literature

Optical anisotropy of structurally modified polycarbonates having cyclohexylidene and methyl substituents using the rotational isomeric state method

An extension of the valence optical scheme-rotational isomeric state method (RIS) applicable to calculation of polarizability tensors and optical anisotropy (γ<SUP>2</SUP>) of molecular fragments constituting substituted polycarbonate chains is presented. The theoretical approach utilizes experimentally derived anisotropic polarizability tensors of molecular groups in order to be able to account for induction effects and interdependence of backbone conformational states. The presence of a cyclohexylidene group at the bisphenyl C<SUB>α</SUB> carbon significantly lowers γ<SUP>2</SUP> due to the low intrinsic polarizability of the cycloaliphatic substituent and due to the conformational states of backbone phenylene rings. Optical anisotropy value of the bisphenyl containing methyl substituents on the phenyl rings is lower than the value for the unsubstituted bisphenyl. Among the structures investigated here, the repeat unit containing cyclohexylidene group at C<SUB>α</SUB> and methyl groups on phenylene rings, leads to the polycarbonate that shows the lowest optical anisotropy. Quantitatively, cyclohexylidene at C<SUB>α</SUB> is more effective in lowering the optical anisotropy than methyl groups on backbone phenylene rings. Calculated &lt;γ<SUP>2</SUP>&gt;/x of the repeat units follows a linear behavior with respect to experimentally observed stress-optical coefficient of these polycarbonates in the melt (C<SUB>m</SUB>). Calculated &lt;γ<SUP>2</SUP>&gt;/x of these structurally modified polycarbonate chains are all lower than that of BPAPC, and the relative trend in &lt;γ<SUP>2</SUP>&gt;/x is similar to that observed for C<SUB>m</SUB> and C<SUB>g</SUB> (glassy state) from experiments in the literature

Molecular Dynamics Simulations of PAA–PMA Polyelectrolyte Copolymers in Dilute Aqueous Solution: Chain Conformations and Hydration Properties

Atomistic molecular dynamics simulations of copolymers of poly­(acrylic acid) (PAA) and poly­(methacrylic acid) (PMA) in dilute aqueous solution were performed as a function of charge density, in explicit solvent medium and counterions. The studied polyelectrolytes follow a general behavior of chain expansion with charge density until a point where the repulsion between the electrostatic charges between the anionic residues is effectively neutralized by the counterions. The average persistence length is found to increase and levels off at higher charge densities, and the values imply the chains to be flexible. With increase in PMA content in the chain, counterions show increased correlation with chain backbone and a systematic reduction in the number of water molecules in the first hydration shell. The intermittent hydrogen-bond correlation function for the hydrogen bonds between the chain residues and water decays faster for PAA chain as compared to PMA, indicating a rigid hydration layer for the latter. The shorter H-bond lifetimes coupled with the slower relaxation indicate that MA–water H-bonds break more easily than those of AA–water H-bonds, but the water molecules remain in the vicinity of the chain because of slow diffusivity and can easily reform the bonds

Anionic polyelectrolyte poly(acrylic acid) (PAA) chain shrinkage in water–ethanol solution in presence of Li⁺ and Cs⁺ metal ions studied by molecular dynamics simulations

<p>Molecular dynamic simulations of anionic polyelectrolyte poly(acrylic acid) (PAA) in water–ethanol solution, specifically Li⁺-PAA and Cs⁺-PAA, were carried out across the solvent composition range 0 ≤ <i>ф</i>_eth ≤ 0.9. Chain collapse (i.e. shrinkage) occurs with increase in <i>ф</i>_eth for both types of counter-ion systems and in agreement with the experiments. The qualitative difference in the collapse point is in agreement with experimental results, with counter-ion specific chain collapse of PAA following the order Li⁺ > Cs⁺. With increase in <i>ф</i>_eth the number of hydrogen-bonds between PAA and water decreases while that between PAA and ethanol increases. At higher level of ethanol content in solution, ethanol molecules displace water molecules from the vicinity of the chain. The analysis of the radial distribution functions shows that counter-ion binding distance of Li⁺ to chain is lesser as compared to that of Cs⁺, as well as a higher coordination number exhibited by Li⁺. Thus, as compared to Cs⁺-PAA, greater number of contact ion pairs formed between Li⁺ and PAA induce chain collapse more easily. The coordination of Li⁺ to PAA is better than that of Cs⁺ throughout the <i>ф</i>_eth range, which could be the reason for the greater extent of PAA chain shrinkage observed in the case of Li⁺. Binding of water molecule to PAA units is stronger in the case of Cs⁺. The backbone dihedral <i>trans</i> probability of both systems displayed a decrease with <i>ф</i>_eth indicating chain shrinkage. The relaxation time of H-bonds between PAA and EtOH is greater for Li⁺-PAA as compared to Cs⁺-PAA system. The enhancement of counter-ion pairs formation is found to be directly responsible for the solvent composition at which chain collapse occurs in the particular system.</p