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, and the gap between male and female life expectancy increased with progression to higher levels of SDI. Some countries with exceptional health performance in 1990 in terms of the difference in observed to expected life expectancy at birth had slower progress on the same measure in 2016.

INTERPRETATION

Globally, mortality rates have decreased across all age groups over the past five decades, with the largest improvements occurring among children younger than 5 years. However, at the national level, considerable heterogeneity remains in terms of both level and rate of changes in age-specific mortality; increases in mortality for certain age groups occurred in some locations. We found evidence that the absolute gap between countries in age-specific death rates has declined, although the relative gap for some age-sex groups increased. Countries that now lead in terms of having higher observed life expectancy than that expected on the basis of development alone, or locations that have either increased this advantage or rapidly decreased the deficit from expected levels, could provide insight into the means to accelerate progress in nations where progress has stalled.

FUNDING

Bill & Melinda Gates Foundation, and the National Institute on Aging and the National Institute of Mental Health of the National Institutes of Health.

Global, regional, and national comparative risk assessment of 84 behavioural, environmental and occupational, and metabolic risks or clusters of risks, 1990-2016: a systematic analysis for the Global Burden of Disease Study 2016

BACKGROUND

The Global Burden of Diseases, Injuries, and Risk Factors Study 2016 (GBD 2016) provides a comprehensive assessment of risk factor exposure and attributable burden of disease. By providing estimates over a long time series, this study can monitor risk exposure trends critical to health surveillance and inform policy debates on the importance of addressing risks in context.

METHODS

We used the comparative risk assessment framework developed for previous iterations of GBD to estimate levels and trends in exposure, attributable deaths, and attributable disability-adjusted life-years (DALYs), by age group, sex, year, and location for 84 behavioural, environmental and occupational, and metabolic risks or clusters of risks from 1990 to 2016. This study included 481 risk-outcome pairs that met the GBD study criteria for convincing or probable evidence of causation. We extracted relative risk (RR) and exposure estimates from 22 717 randomised controlled trials, cohorts, pooled cohorts, household surveys, census data, satellite data, and other sources, according to the GBD 2016 source counting methods. Using the counterfactual scenario of theoretical minimum risk exposure level (TMREL), we estimated the portion of deaths and DALYs that could be attributed to a given risk. Finally, we explored four drivers of trends in attributable burden: population growth, population ageing, trends in risk exposure, and all other factors combined.

FINDINGS

Since 1990, exposure increased significantly for 30 risks, did not change significantly for four risks, and decreased significantly for 31 risks. Among risks that are leading causes of burden of disease, child growth failure and household air pollution showed the most significant declines, while metabolic risks, such as body-mass index and high fasting plasma glucose, showed significant increases. In 2016, at Level 3 of the hierarchy, the three leading risk factors in terms of attributable DALYs at the global level for men were smoking (124·1 million DALYs [95% UI 111·2 million to 137·0 million]), high systolic blood pressure (122·2 million DALYs [110·3 million to 133·3 million], and low birthweight and short gestation (83·0 million DALYs [78·3 million to 87·7 million]), and for women, were high systolic blood pressure (89·9 million DALYs [80·9 million to 98·2 million]), high body-mass index (64·8 million DALYs [44·4 million to 87·6 million]), and high fasting plasma glucose (63·8 million DALYs [53·2 million to 76·3 million]). In 2016 in 113 countries, the leading risk factor in terms of attributable DALYs was a metabolic risk factor. Smoking remained among the leading five risk factors for DALYs for 109 countries, while low birthweight and short gestation was the leading risk factor for DALYs in 38 countries, particularly in sub-Saharan Africa and South Asia. In terms of important drivers of change in trends of burden attributable to risk factors, between 2006 and 2016 exposure to risks explains an 9·3% (6·9-11·6) decline in deaths and a 10·8% (8·3-13·1) decrease in DALYs at the global level, while population ageing accounts for 14·9% (12·7-17·5) of deaths and 6·2% (3·9-8·7) of DALYs, and population growth for 12·4% (10·1-14·9) of deaths and 12·4% (10·1-14·9) of DALYs. The largest contribution of trends in risk exposure to disease burden is seen between ages 1 year and 4 years, where a decline of 27·3% (24·9-29·7) of the change in DALYs between 2006 and 2016 can be attributed to declines in exposure to risks.

INTERPRETATION

Increasingly detailed understanding of the trends in risk exposure and the RRs for each risk-outcome pair provide insights into both the magnitude of health loss attributable to risks and how modification of risk exposure has contributed to health trends. Metabolic risks warrant particular policy attention, due to their large contribution to global disease burden, increasing trends, and variable patterns across countries at the same level of development. GBD 2016 findings show that, while it has huge potential to improve health, risk modification has played a relatively small part in the past decade.

FUNDING

The Bill & Melinda Gates Foundation, Bloomberg Philanthropies.

Global, regional, and national age-sex specific mortality for 264 causes of death, 1980-2016: a systematic analysis for the Global Burden of Disease Study 2016

BACKGROUND

Monitoring levels and trends in premature mortality is crucial to understanding how societies can address prominent sources of early death. The Global Burden of Disease 2016 Study (GBD 2016) provides a comprehensive assessment of cause-specific mortality for 264 causes in 195 locations from 1980 to 2016. This assessment includes evaluation of the expected epidemiological transition with changes in development and where local patterns deviate from these trends.

METHODS

We estimated cause-specific deaths and years of life lost (YLLs) by age, sex, geography, and year. YLLs were calculated from the sum of each death multiplied by the standard life expectancy at each age. We used the GBD cause of death database composed of: vital registration (VR) data corrected for under-registration and garbage coding; national and subnational verbal autopsy (VA) studies corrected for garbage coding; and other sources including surveys and surveillance systems for specific causes such as maternal mortality. To facilitate assessment of quality, we reported on the fraction of deaths assigned to GBD Level 1 or Level 2 causes that cannot be underlying causes of death (major garbage codes) by location and year. Based on completeness, garbage coding, cause list detail, and time periods covered, we provided an overall data quality rating for each location with scores ranging from 0 stars (worst) to 5 stars (best). We used robust statistical methods including the Cause of Death Ensemble model (CODEm) to generate estimates for each location, year, age, and sex. We assessed observed and expected levels and trends of cause-specific deaths in relation to the Socio-demographic Index (SDI), a summary indicator derived from measures of average income per capita, educational attainment, and total fertility, with locations grouped into quintiles by SDI. Relative to GBD 2015, we expanded the GBD cause hierarchy by 18 causes of death for GBD 2016.

FINDINGS

The quality of available data varied by location. Data quality in 25 countries rated in the highest category (5 stars), while 48, 30, 21, and 44 countries were rated at each of the succeeding data quality levels. Vital registration or verbal autopsy data were not available in 27 countries, resulting in the assignment of a zero value for data quality. Deaths from non-communicable diseases (NCDs) represented 72·3% (95% uncertainty interval [UI] 71·2-73·2) of deaths in 2016 with 19·3% (18·5-20·4) of deaths in that year occurring from communicable, maternal, neonatal, and nutritional (CMNN) diseases and a further 8·43% (8·00-8·67) from injuries. Although age-standardised rates of death from NCDs decreased globally between 2006 and 2016, total numbers of these deaths increased; both numbers and age-standardised rates of death from CMNN causes decreased in the decade 2006-16-age-standardised rates of deaths from injuries decreased but total numbers varied little. In 2016, the three leading global causes of death in children under-5 were lower respiratory infections, neonatal preterm birth complications, and neonatal encephalopathy due to birth asphyxia and trauma, combined resulting in 1·80 million deaths (95% UI 1·59 million to 1·89 million). Between 1990 and 2016, a profound shift toward deaths at older ages occurred with a 178% (95% UI 176-181) increase in deaths in ages 90-94 years and a 210% (208-212) increase in deaths older than age 95 years. The ten leading causes by rates of age-standardised YLL significantly decreased from 2006 to 2016 (median annualised rate of change was a decrease of 2·89%); the median annualised rate of change for all other causes was lower (a decrease of 1·59%) during the same interval. Globally, the five leading causes of total YLLs in 2016 were cardiovascular diseases; diarrhoea, lower respiratory infections, and other common infectious diseases; neoplasms; neonatal disorders; and HIV/AIDS and tuberculosis. At a finer level of disaggregation within cause groupings, the ten leading causes of total YLLs in 2016 were ischaemic heart disease, cerebrovascular disease, lower respiratory infections, diarrhoeal diseases, road injuries, malaria, neonatal preterm birth complications, HIV/AIDS, chronic obstructive pulmonary disease, and neonatal encephalopathy due to birth asphyxia and trauma. Ischaemic heart disease was the leading cause of total YLLs in 113 countries for men and 97 countries for women. Comparisons of observed levels of YLLs by countries, relative to the level of YLLs expected on the basis of SDI alone, highlighted distinct regional patterns including the greater than expected level of YLLs from malaria and from HIV/AIDS across sub-Saharan Africa; diabetes mellitus, especially in Oceania; interpersonal violence, notably within Latin America and the Caribbean; and cardiomyopathy and myocarditis, particularly in eastern and central Europe. The level of YLLs from ischaemic heart disease was less than expected in 117 of 195 locations. Other leading causes of YLLs for which YLLs were notably lower than expected included neonatal preterm birth complications in many locations in both south Asia and southeast Asia, and cerebrovascular disease in western Europe.

INTERPRETATION

The past 37 years have featured declining rates of communicable, maternal, neonatal, and nutritional diseases across all quintiles of SDI, with faster than expected gains for many locations relative to their SDI. A global shift towards deaths at older ages suggests success in reducing many causes of early death. YLLs have increased globally for causes such as diabetes mellitus or some neoplasms, and in some locations for causes such as drug use disorders, and conflict and terrorism. Increasing levels of YLLs might reflect outcomes from conditions that required high levels of care but for which effective treatments remain elusive, potentially increasing costs to health systems.

FUNDING

Bill & Melinda Gates Foundation.

Measuring progress and projecting attainment on the basis of past trends of the health-related Sustainable Development Goals in 188 countries: an analysis from the Global Burden of Disease Study 2016

BACKGROUND

The UN's Sustainable Development Goals (SDGs) are grounded in the global ambition of "leaving no one behind". Understanding today's gains and gaps for the health-related SDGs is essential for decision makers as they aim to improve the health of populations. As part of the Global Burden of Diseases, Injuries, and Risk Factors Study 2016 (GBD 2016), we measured 37 of the 50 health-related SDG indicators over the period 1990-2016 for 188 countries, and then on the basis of these past trends, we projected indicators to 2030.

METHODS

We used standardised GBD 2016 methods to measure 37 health-related indicators from 1990 to 2016, an increase of four indicators since GBD 2015. We substantially revised the universal health coverage (UHC) measure, which focuses on coverage of essential health services, to also represent personal health-care access and quality for several non-communicable diseases. We transformed each indicator on a scale of 0-100, with 0 as the 2·5th percentile estimated between 1990 and 2030, and 100 as the 97·5th percentile during that time. An index representing all 37 health-related SDG indicators was constructed by taking the geometric mean of scaled indicators by target. On the basis of past trends, we produced projections of indicator values, using a weighted average of the indicator and country-specific annualised rates of change from 1990 to 2016 with weights for each annual rate of change based on out-of-sample validity. 24 of the currently measured health-related SDG indicators have defined SDG targets, against which we assessed attainment.

FINDINGS

Globally, the median health-related SDG index was 56·7 (IQR 31·9-66·8) in 2016 and country-level performance markedly varied, with Singapore (86·8, 95% uncertainty interval 84·6-88·9), Iceland (86·0, 84·1-87·6), and Sweden (85·6, 81·8-87·8) having the highest levels in 2016 and Afghanistan (10·9, 9·6-11·9), the Central African Republic (11·0, 8·8-13·8), and Somalia (11·3, 9·5-13·1) recording the lowest. Between 2000 and 2016, notable improvements in the UHC index were achieved by several countries, including Cambodia, Rwanda, Equatorial Guinea, Laos, Turkey, and China; however, a number of countries, such as Lesotho and the Central African Republic, but also high-income countries, such as the USA, showed minimal gains. Based on projections of past trends, the median number of SDG targets attained in 2030 was five (IQR 2-8) of the 24 defined targets currently measured. Globally, projected target attainment considerably varied by SDG indicator, ranging from more than 60% of countries projected to reach targets for under-5 mortality, neonatal mortality, maternal mortality ratio, and malaria, to less than 5% of countries projected to achieve targets linked to 11 indicator targets, including those for childhood overweight, tuberculosis, and road injury mortality. For several of the health-related SDGs, meeting defined targets hinges upon substantially faster progress than what most countries have achieved in the past.

INTERPRETATION

GBD 2016 provides an updated and expanded evidence base on where the world currently stands in terms of the health-related SDGs. Our improved measure of UHC offers a basis to monitor the expansion of health services necessary to meet the SDGs. Based on past rates of progress, many places are facing challenges in meeting defined health-related SDG targets, particularly among countries that are the worst off. In view of the early stages of SDG implementation, however, opportunity remains to take actions to accelerate progress, as shown by the catalytic effects of adopting the Millennium Development Goals after 2000. With the SDGs' broader, bolder development agenda, multisectoral commitments and investments are vital to make the health-related SDGs within reach of all populations.

FUNDING

Bill & Melinda Gates Foundation.

Improving quality and outcomes of stroke care in hospitals: Protocol and statistical analysis plan for the Stroke123 implementation study

Rationale The effectiveness of clinician-focused interventions to improve stroke care is uncertain. Aims To determine whether an organizational intervention can improve the quality of stroke care over usual care. Sample size estimates To detect an absolute 10% difference in overall performance (composite outcome), a minimum of 21 hospitals and 843 patients per group was determined. Methods and design Before and after controlled design in hospitals in Queensland, Australia. Intervention Externally facilitated program (StrokeLink) using outreach workshops incorporating clinical performance feedback, patient outcomes (survival, quality of life at 90-180 days), local barrier assessments to best practice care, action planning, and ongoing support. Descriptive and multivariable analyses adjusted for patient correlations by hospital (intention-to-treat method). Context Concurrent implementation of financial incentives to increase stroke unit access and use of the Australian Stroke Clinical Registry for performance monitoring. Study outcome(s) Primary outcome: net change in composite score (i.e. total number of process indicators achieved divided by the sum of eligible indicators for each cohort).

SECONDARY OUTCOMES

change in individual indicators, change in composite score comparing hospitals that did or did not develop action plans (per-protocol analysis), impact on 90-180-day health outcomes. Sensitivity analyses: hospital self-rated status, alternate cross-sectional audit data (Stroke Foundation). To account for temporal effects, comparison of Queensland hospital performance relative to other Australian hospitals will also be undertaken. Discussion Twenty-one hospitals were recruited; however, one was unable to participate within the study time frame. Workshops were held between 11 March 2014 and 7 November 2014. Data are ready for analysis.

Global stroke statistics: An update of mortality data from countries using a broad code of "cerebrovascular diseases"

Background Current information on mortality attributed to stroke among different countries is important for policy development and monitoring prevention strategies. Unfortunately, mortality data reported to the World Health Organization by different countries are inconsistent. Aims and/or hypothesis To update the repository of the most recent country-specific data on mortality from stroke for countries that provide data using a broad code for "cerebrovascular disease." Methods Data on mortality from stroke were obtained from the World Health Organization mortality database. We searched for countries that provided data, since 1999, on a combined category of "cerebrovascular disease" (code 1609) that incorporated International Classification of Diseases (10th edition) codes I60-I69. Using population denominators provided by the World Health Organization for the same year when available, or alternatively estimates obtained from the United Nations, we calculated crude mortality from "cerebrovascular disease" and mortality adjusted to the World Health Organization world population. We used the most recent year reported to the World Health Organization, as well as comparing changes over time. Results Since 1999, seven countries have provided these mortality data. Among these countries, crude mortality was greatest in the Russian Federation (in 2011), Ukraine (2012), and Belarus (2011) and was greater in women than men in these countries. Crude mortality was positively correlated with the proportion of the population aged ≥65 years but not with time. Age-adjusted mortality was greatest in the Russian Federation and Turkmenistan, and greater in men than women. Over time, mortality declined, with the greatest decline per annum evident in Kazakhstan (8.7%) and the Russian Federation (7.0%). Conclusions Among countries that provided data to the World Health Organization using a broad category of "cerebrovascular disease," there was a decline in mortality in two of the countries that previously had some of the largest mortality rates for stroke.

Strategies to Improve Stroke Care Services in Low- and Middle-Income Countries: A Systematic Review

Background: The burden of stroke in low- and middle-income countries (LMICs) is large and increasing, challenging the already stretched health-care services. Aims and Objectives: To determine the quality of existing stroke-care services in LMICs and to highlight indigenous, inexpensive, evidence-based implementable strategies being used in stroke-care. Methods: A detailed literature search was undertaken using PubMed and Google scholar from January 1966 to October 2015 using a range of search terms. Of 921 publications, 373 papers were shortlisted and 31 articles on existing stroke-services were included. Results: We identified efficient models of ambulance transport and pre-notification. Stroke Units (SU) are available in some countries, but are relatively sparse and mostly provided by the private sector. Very few patients were thrombolysed; this could be increased with telemedicine and governmental subsidies. Adherence to secondary preventive drugs is affected by limited availability and affordability, emphasizing the importance of primary prevention. Training of paramedics, care-givers and nurses in post-stroke care is feasible. Conclusion: In this systematic review, we found several reports on evidence-based implementable stroke services in LMICs. Some strategies are economic, feasible and reproducible but remain untested. Data on their outcomes and sustainability is limited. Further research on implementation of locally and regionally adapted stroke-services and cost-effective secondary prevention programs should be a priority.

Epidemiology of Intracranial and Extracranial Large Artery Stenosis in a Population-Based Study of Stroke in the Middle East

BACKGROUND

Intracranial large-artery disease (LAD) is a predominant vascular lesion found in patients with stroke of Asian, African, and Hispanic origin, whereas extracranial LAD is more prevalent among Caucasians. These patterns are not well-established in the Middle East. We aimed to characterize the incidence, risk factors, and long-term outcome of LAD strokes in a Middle-Eastern population.

METHODS

The Mashhad Stroke Incidence Study is a community-based study that prospectively ascertained all cases of stroke among the 450,229 inhabitants of Mashhad, Iran between 2006 and 2007. Ischemic strokes were classified according to the TOAST criteria. Duplex-ultrasonography (98.6%), MR-angiography (8.3%), CT-angiography (11%), and digital-subtraction angiography (9.7%) were performed to identify involvements. Vessels were considered stenotic when the lumen was occluded by >50%.

RESULTS

We identified 72 cases (15.99 per 100,000) of incident LAD strokes (mean age 67.6 ± 11.7). Overall, 77% had extracranial LAD (58% male, mean age 69.8 ± 10.3; 50 [89%] carotid vs. 6 [11%] vertebral artery), and the remaining 23% (56% male, mean age 60.2 ± 13.4; 69% anterior-circulation stenosis) had intracranial LAD strokes. We were unable to detect differences in case-fatality between extracranial (1-year: 28.6%; 5-year: 59.8%) and intracranial diseases (1-year: 18.8%; 5-year: 36.8%; log-rank; p = 0.1).

CONCLUSION

Extracranial carotid stenosis represents the majority of LAD strokes in this population. Thus, public health strategies may best be developed in such a way that they are targeted toward the risk factors that contribute to extracranial stenosis.

Long-term unmet needs and associated factors in stroke or TIA survivors

Objective:

To extensively investigate long-term unmet needs in survivors of stroke or TIA and to identify factors associated with these unmet needs.

Methods:

Community-dwelling adults were invited to participate in a survey ≥2 years after discharge for stroke/TIA. Unmet needs were assessed across 5 domains: activities and participation, environmental factors, body functions, post–acute care, and secondary prevention. Factors associated with unmet needs were determined with multivariable negative binomial regression.

Results:

Of 485 participants invited to complete the survey, 391 (81%) responded (median age 73 years, 67% male). Most responders (87%) reported unmet needs in ≥1 of the measured domains, particularly in secondary prevention (71%). Factors associated with fewer unmet needs included older age (incident rate ratio [IRR] 0.62, 95% confidence interval [CI] 0.50–0.77), greater functional ability (IRR 0.33, 95% CI 0.17–0.67), and reporting that the general practitioner was the most important in care (IRR 0.69, 95% CI 0.57–0.84). Being depressed (IRR 1.61, 95% CI 1.23–2.10) and receiving community services after stroke (IRR 1.45, 95% CI 1.16–1.82) were associated with more unmet needs.

Conclusions:

Survivors of stroke/TIA reported considerable unmet needs ≥2 years after discharge, particularly in secondary prevention. The factors associated with unmet needs could help guide policy decisions, particularly for tailoring care and support services provided after discharge.

The potential health and economic impact of improving stroke care standards for Australia

Background

Evidence of the burden of suboptimal stroke care should expedite quality improvement. We aimed to estimate the health and economic impact of improving acute stroke management to best practice standards using Australia as a case study.

Methods

Hospital performance in Australia was estimated using data from the National Stroke Audit of Acute Services 2013. The percentage of patients provided evidence-based therapies in all hospitals was compared to that achieved in the aggregate of top performing benchmark hospitals (that included between them, a minimum contribution of 15% of all cases audited). The number of additional patients who would receive therapies if this performance gap was rectified was applied to a standardized economic simulation model that comprised stroke rates and resource-use estimates from the North East Melbourne Stroke Incidence Study applied to the 2013 Australian population.

Results

In 2013, 41,398 patients were estimated to have been hospitalized with stroke. If acute care was improved to that of Australian benchmarks, there would be an additional 15,317 patients accessing stroke units; 1960 receiving thrombolysis; and 4007 being treated with antihypertensive medication, 3082 with antiplatelet medication, 2179 with anticoagulant medication, and 3514 with lipid-lowering therapy. Approximately 9329 disability-adjusted life years could be avoided. This additional care provided would be cost effective at AUD 3304 per disability adjusted life year avoided.

Conclusion

The benefits of reducing evidence–practice gaps in Australia are considerable. Further investment in initiatives to optimize hospital care is justified.

Developing consensus measures for global programs: lessons from the Global Alliance for Chronic Diseases Hypertension research program

BACKGROUND

The imperative to improve global health has prompted transnational research partnerships to investigate common health issues on a larger scale. The Global Alliance for Chronic Diseases (GACD) is an alliance of national research funding agencies. To enhance research funded by GACD members, this study aimed to standardise data collection methods across the 15 GACD hypertension research teams and evaluate the uptake of these standardised measurements. Furthermore we describe concerns and difficulties associated with the data harmonisation process highlighted and debated during annual meetings of the GACD funded investigators. With these concerns and issues in mind, a working group comprising representatives from the 15 studies iteratively identified and proposed a set of common measures for inclusion in each of the teams' data collection plans. One year later all teams were asked which consensus measures had been implemented.

RESULTS

Important issues were identified during the data harmonisation process relating to data ownership, sharing methodologies and ethical concerns. Measures were assessed across eight domains; demographic; dietary; clinical and anthropometric; medical history; hypertension knowledge; physical activity; behavioural (smoking and alcohol); and biochemical domains. Identifying validated measures relevant across a variety of settings presented some difficulties. The resulting GACD hypertension data dictionary comprises 67 consensus measures. Of the 14 responding teams, only two teams were including more than 50 consensus variables, five teams were including between 25 and 50 consensus variables and four teams were including between 6 and 24 consensus variables, one team did not provide details of the variables collected and two teams did not include any of the consensus variables as the project had already commenced or the measures were not relevant to their study.

CONCLUSIONS

Deriving consensus measures across diverse research projects and contexts was challenging. The major barrier to their implementation was related to the time taken to develop and present these measures. Inclusion of consensus measures into future funding announcements would facilitate researchers integrating these measures within application protocols. We suggest that adoption of consensus measures developed here, across the field of hypertension, would help advance the science in this area, allowing for more comparable data sets and generalizable inferences.

Effectiveness of an Intervention to Improve Risk Factor Knowledge in Patients With Stroke: A Randomized Controlled Trial

BACKGROUND AND PURPOSE

Despite the benefit of risk awareness in secondary prevention, survivors of stroke are often unaware of their risk factors. We determined whether a nurse-led intervention improved knowledge of risk factors in people with stroke or transient ischemic attack.

METHODS

Prospective study nested within a randomized controlled trial of risk factor management in survivors of stroke or transient ischemic attack.

INTERVENTION

3 nurse education visits and specialist review of care plans.

OUTCOME

unprompted knowledge of risk factors of stroke or transient ischemic attack at 24 months. Effect of intervention on knowledge and factors associated with knowledge were determined using multivariable regression models.

RESULTS

Knowledge was assessed in 268 consecutive participants from the main trial, 128 in usual care and 140 in the intervention. Overall, 34% of participants were unable to name any risk factor. In adjusted analyses, the intervention group had better overall knowledge than controls (incidence risk ratio, 1.26; 95% confidence interval, 1.00-1.58). Greater functional ability and polypharmacy were associated with better knowledge and older age and having more comorbidities associated with poorer knowledge.

CONCLUSIONS

Overall knowledge of risk factors of stroke or transient ischemic attack was better in the intervention group than controls. However, knowledge was generally poor. New and more effective strategies are required, especially in subgroups identified as having poor knowledge.

CLINICAL TRIAL REGISTRATION

URL: http://www.anzctr.org.au. Unique identifier: ACTRN12608000166370.

Sex Differences in Long-Term Mortality After Stroke in the INSTRUCT (INternational STRoke oUtComes sTudy)

Background—

Women are reported to have greater mortality after stroke than men, but the reasons are uncertain. We examined sex differences in mortality at 1 and 5 years after stroke and identified factors contributing to these differences.

Methods and Results—

Individual participant data for incident strokes were obtained from 13 population-based incidence studies conducted in Europe, Australasia, South America, and the Caribbean between 1987 and 2013. Data on sociodemographics, stroke-related factors, prestroke health, and 1- and 5-year survival were obtained. Poisson modeling was used to estimate the mortality rate ratio (MRR) for women compared with men at 1 year (13 studies) and 5 years (8 studies) after stroke. Study-specific adjusted MRRs were pooled to create a summary estimate using random-effects meta-analysis. Overall, 16 957 participants with first-ever stroke followed up at 1 year and 13 216 followed up to 5 years were included. Crude pooled mortality was greater for women than men at 1 year (MRR 1.35; 95% confidence interval, 1.24–1.47) and 5 years (MRR 1.24; 95% confidence interval, 1.12–1.38). However, these pooled sex differences were reversed after adjustment for confounding factors (1 year MRR, 0.81; 95% confidence interval, 0.72–0.92 and 5-year MRR, 0.76; 95% confidence interval, 0.65–0.89). Confounding factors included age, prestroke functional limitations, stroke severity, and history of atrial fibrillation.

Conclusions—

Greater mortality in women is mostly because of age but also stroke severity, atrial fibrillation, and prestroke functional limitations. Lower survival after stroke among the elderly is inevitable, but there may be opportunities for intervention, including better access to evidence-based care for cardiovascular and general health.

Abstract TP171: Differences Between Men and Women in Long-term Participation Restriction After Stroke: The International Stroke Outcomes Study (INSTRUCT)

Introduction: As women suffer worse functional outcomes of stroke than men, they may also face more challenges with community reintegration but data are scarce. We examined sex differences in participation after stroke and which factors might account for these disparities.

Methods: INSTRUCT is an individual participant data pooling study of incident strokes obtained from 13 population-based cohorts worldwide. Two of the cohorts (Melbourne ’96-‘99 and Auckland ’02-‘03) included assessment of participation at 5 years after stroke using the London Handicap Scale (LHS). The LHS is used to assess the individual’s perspective of their involvement in life situations including orientation (person’s awareness of surroundings), physical independence, mobility, occupation, social interaction and economic self-efficiency. The total score ranges from 0 (worst disadvantage) to 100 (no disadvantage). Linear regression was used to compare LHS total scores and sub-domains for women compared to men. Study-specific multivariable models incorporated adjustment for socio-demographics, stroke-related factors, pre-stroke health and post-stroke factors were combined using random-effects meta-analysis.

Results: At 5 years after stroke, there were data on participation for 351/592 (59%) of survivors in Melbourne and 266/881 (30%) of survivors in Auckland. Women suffered greater participation restriction than men (total LHS, pooled mean difference, MD -5.55 [95% CI -8.47, -2.63]). The magnitude of the difference attenuated after adjusting for covariates (pooled MD -2.48 [-4.99, 0.03]). Significant confounders in study-specific models included age, stroke severity, pre-stroke dependency and pre-stroke dementia for Melbourne; and age, stroke severity and pre-stroke dependency for Auckland. In sub-dimensions, women had greater restriction than men in mobility, physical independence and occupation. Additionally, women in Melbourne experienced poorer social integration and orientation than men.

Conclusion: Greater restriction in participation after stroke among women than men was mostly attributable to their advanced age and greater pre-stroke dependency. Interventions targeting participation could reduce the impact of stroke in women.

Innovative Approaches to Hypertension Control in Low- and Middle-Income Countries

Elevated blood pressure, a major risk factor for ischemic heart disease, heart failure, and stroke, is the leading global risk for mortality. Treatment and control rates are very low in low- and middle-income countries. There is an urgent need to address this problem. The Global Alliance for Chronic Diseases sponsored research projects focus on controlling hypertension, including community engagement, salt reduction, salt substitution, task redistribution, mHealth, and fixed-dose combination therapies. This paper reviews the rationale for each approach and summarizes the experience of some of the research teams. The studies demonstrate innovative and practical methods for improving hypertension control.

Abstract 51: Differences in Stroke Management do not Account for the Greater Long-term Mortality After Stroke in Women Compared to Men: Australian Stroke Clinical Registry (AuSCR)

Introduction: Women have been reported to receive evidence-based care less often than men, but it is uncertain whether this contributes to sex differences in outcomes after stroke. We examined this using data obtained from the Australian Stroke Clinical Registry (AuSCR).

Methods: We included first-ever strokes admitted to 40 hospitals participating in the AuSCR during 2010-2013. Mortality one year after stroke was obtained from linkage to the National Death Index. Multilevel Poisson modelling, accounting for hospital, was used to estimate the mortality rate ratio (MRR) for women compared to men. Multivariable models were adjusted for sociodemographics, stroke type, severity (ability to walk on admission) and the provision of evidence-based therapies while in hospital (stroke unit care, thrombolysis, secondary prevention medications, dysphagia screening and mobilization).

Results: Data were available for 9,549 strokes (47% women, 80% ischaemic stroke). Women, compared to men, were older (mean [SD] 75.0 [15.0] vs 70.3 [13.9], p<0.001) and less able to walk on admission (32% vs 41%, p<0.001). Overall, there were no sex differences in access to evidence-based therapies in hospital, although it appeared that slightly fewer women were admitted to a stroke unit (79% vs 81%, p=0.001). In a subset of patients from Queensland (n=3,013), women were less often mobilised (74% vs 79%, p=0.04) or administered aspirin within 48 hours of stroke onset (66% vs 74%, p<0.001). Mortality was greater in women than men at one year (MRR crude 1.42 [95% CI 1.31, 1.55]). This association was attenuated when adjusting for age and severity of stroke (MRR adjusted 1.00 [95% CI 0.92, 1.09] but not by any of the evidence-based therapies.

Conclusion: Greater mortality in women was associated with differences in age and stroke severity and not differences in access to care. Improvements in care for the elderly and the management of modifiable factors of stroke severity should reduce sex differences in outcomes.

Global Burden of Hypertension and Systolic Blood Pressure of at Least 110 to 115 mm Hg, 1990-2015

IMPORTANCE

Elevated systolic blood (SBP) pressure is a leading global health risk. Quantifying the levels of SBP is important to guide prevention policies and interventions.

OBJECTIVE

To estimate the association between SBP of at least 110 to 115 mm Hg and SBP of 140 mm Hg or higher and the burden of different causes of death and disability by age and sex for 195 countries and territories, 1990-2015.

DESIGN

A comparative risk assessment of health loss related to SBP. Estimated distribution of SBP was based on 844 studies from 154 countries (published 1980-2015) of 8.69 million participants. Spatiotemporal Gaussian process regression was used to generate estimates of mean SBP and adjusted variance for each age, sex, country, and year. Diseases with sufficient evidence for a causal relationship with high SBP (eg, ischemic heart disease, ischemic stroke, and hemorrhagic stroke) were included in the primary analysis.

MAIN OUTCOMES AND MEASURES

Mean SBP level, cause-specific deaths, and health burden related to SBP (≥110-115 mm Hg and also ≥140 mm Hg) by age, sex, country, and year.

RESULTS

Between 1990-2015, the rate of SBP of at least 110 to 115 mm Hg increased from 73 119 (95% uncertainty interval [UI], 67 949-78 241) to 81 373 (95% UI, 76 814-85 770) per 100 000, and SBP of 140 mm Hg or higher increased from 17 307 (95% UI, 17 117-17 492) to 20 526 (95% UI, 20 283-20 746) per 100 000. The estimated annual death rate per 100 000 associated with SBP of at least 110 to 115 mm Hg increased from 135.6 (95% UI, 122.4-148.1) to 145.2 (95% UI 130.3-159.9) and the rate for SBP of 140 mm Hg or higher increased from 97.9 (95% UI, 87.5-108.1) to 106.3 (95% UI, 94.6-118.1). For loss of DALYs associated with systolic blood pressure of 140 mm Hg or higher, the loss increased from 95.9 million (95% uncertainty interval [UI], 87.0-104.9 million) to 143.0 million (95% UI, 130.2-157.0 million) [corrected], and for SBP of 140 mm Hg or higher, the loss increased from 5.2 million (95% UI, 4.6-5.7 million) to 7.8 million (95% UI, 7.0-8.7 million). The largest numbers of SBP-related deaths were caused by ischemic heart disease (4.9 million [95% UI, 4.0-5.7 million]; 54.5%), hemorrhagic stroke (2.0 million [95% UI, 1.6-2.3 million]; 58.3%), and ischemic stroke (1.5 million [95% UI, 1.2-1.8 million]; 50.0%). In 2015, China, India, Russia, Indonesia, and the United States accounted for more than half of the global DALYs related to SBP of at least 110 to 115 mm Hg.

CONCLUSIONS AND RELEVANCE

In international surveys, although there is uncertainty in some estimates, the rate of elevated SBP (≥110-115 and ≥140 mm Hg) increased substantially between 1990 and 2015, and DALYs and deaths associated with elevated SBP also increased. Projections based on this sample suggest that in 2015, an estimated 3.5 billion adults had SBP of at least 110 to 115 mm Hg and 874 million adults had SBP of 140 mm Hg or higher.

Factors associated with awareness, treatment and control of hypertension in a disadvantaged rural Indian population

The aim of this study was to identify factors associated with awareness, treatment and control of hypertension in a rural setting in India. Following screening of the population, all individuals with hypertension (blood pressure (BP) ⩾140/90 mm Hg or taking antihypertensive medications) were invited to participate in this study. We measured BP, height, weight, skinfolds, waist and hip circumference, and administered a questionnaire to obtain information regarding socioeconomic and behavioural characteristics. Multivariable logistic regression was used to determine factors associated with awareness, treatment and control of hypertension. We recruited 277 individuals with hypertension. Awareness (43%), treatment (33%) and control (27%) of hypertension were poor. Greater distance to health services (odds ratio (OR) 0.56 (95% confidence interval (CI)) 0.32-0.98) was associated with poor awareness of hypertension while having had BP measured within the previous year (OR 4.72, 95% CI 2.71-8.22), older age and greater per cent body fat were associated with better awareness. Factors associated with treatment of hypertension were having had BP measured within the previous year (OR 6.18, 95% CI 3.23-11.82), age ⩾65 years, physical inactivity and greater per cent body fat. The only factor associated with control of hypertension was greater per cent body fat (OR 1.05, 95% CI 1.01-1.11). Improving geographic access and utilisation of health services should improve awareness and treatment of hypertension in this rural population. Further research is necessary to determine drivers of control.

Incidence, recurrence, and long-term survival of ischemic stroke subtypes: A population-based study in the Middle East

Background Incidence, risk factors, case fatality and survival rates of ischemic stroke subtypes are unknown in the Middle East due to the lack of community-based incidence stroke studies in this region. Aim To characterize ischemic stroke subtypes in a Middle Eastern population. Methods The Mashad Stroke Incidence Study is a community-based study that prospectively ascertained all cases of stroke among the 450,229 inhabitants of Mashhad, Iran between 2006 and 2007. We identified 512 cases of first-ever ischemic stroke [264 men (mean age 65.5 ± 14.4) and 248 women (mean age 64.14 ± 14.5)]. Subtypes of ischemic stroke were classified according to the TOAST criteria. Incidence rates were age standardized to the WHO and European populations. Results The proportion of stroke subtypes was distributed as follows: 14.1% large artery disease, 15% cardioembolic, 22.5% small artery disease, 43.9% undetermined and 4.5% other. The greatest overall incidence rates were attributed to undetermined infarction (49.97/100,000) followed by small artery disease (25.54/100,000). Prevalence of hypertension, diabetes and atrial fibrillation differed among ischemic stroke subtypes. Overall, there were 268 (52.34%) deaths and 73 (14.25%) recurrent strokes at five years after incident ischemic stroke, with the greatest risk of recurrence seen in the large artery disease (35.6%) and cardioembolic (35.5%) subgroups. Survival was similar in men and women for each stroke subtype. Conclusions We observed markedly greater incidence rates of ischemic stroke subtypes than in other countries within the Mashad Stroke Incidence Study after age standardization. Our findings should be considered when planning prevention and stroke care services in this region.

STROKOG (stroke and cognition consortium): An international consortium to examine the epidemiology, diagnosis, and treatment of neurocognitive disorders in relation to cerebrovascular disease

INTRODUCTION

The Stroke and Cognition consortium (STROKOG) aims to facilitate a better understanding of the determinants of vascular contributions to cognitive disorders and help improve the diagnosis and treatment of vascular cognitive disorders (VCD).

METHODS

Longitudinal studies with ≥75 participants who had suffered or were at risk of stroke or TIA and which evaluated cognitive function were invited to join STROKOG. The consortium will facilitate projects investigating rates and patterns of cognitive decline, risk factors for VCD, and biomarkers of vascular dementia.

RESULTS

Currently, STROKOG includes 25 (21 published) studies, with 12,092 participants from five continents. The duration of follow-up ranges from 3 months to 21 years.

DISCUSSION

Although data harmonization will be a key challenge, STROKOG is in a unique position to reuse and combine international cohort data and fully explore patient level characteristics and outcomes. STROKOG could potentially transform our understanding of VCD and have a worldwide impact on promoting better vascular cognitive outcomes.