Shanthi Mendis

Global variation in stroke burden and mortality: estimates from monitoring, surveillance, and modelling

BACKGROUND Recent improvements in the monitoring and modelling of stroke have led to more reliable estimates of stroke mortality and burden worldwide. However, little is known about the global distribution of stroke and its relations to the prevalence of cardiovascular disease risk factors and sociodemographic and economic characteristics. METHODS National estimates of stroke mortality and burden (measured in disability-adjusted life years [DALYs]) were calculated from monitoring vital statistics, a systematic review of studies that report disease surveillance, and modelling as part of the WHO Global Burden of Disease programme. Similar methods were used to generate standardised measures of the national prevalence of cardiovascular risk factors. Risk factors other than diabetes and disease burden estimates were age-adjusted and sex-adjusted to the WHO standard population. FINDINGS There was a ten-fold difference in rates of stroke mortality and DALY loss between the most-affected and the least-affected countries. Rates of stroke mortality and DALY loss were highest in eastern Europe, north Asia, central Africa, and the south Pacific. National per capita income was the strongest predictor of mortality and DALY loss rates (p<0.0001) even after adjustment for cardiovascular risk factors (p<0.0001). Prevalences of cardiovascular risk factors measured at a national level were generally poor predictors of national stroke mortality rates and burden, although raised mean systolic blood pressure (p=0.028) and low body-mass index (p=0.017) predicted stroke mortality, and greater prevalence of smoking predicted both stroke mortality (p=0.041) and DALY-loss rates (p=0.034). INTERPRETATION Rates of stroke mortality and burden vary greatly among countries, but low-income countries are the most affected. Current measures of the prevalence of cardiovascular risk factors at the population level poorly predict overall stroke mortality and burden and do not explain the greater burden in low-income countries.

The contribution of chronic kidney disease to the global burden of major noncommunicable diseases.

Noncommunicable diseases (NCDs) are the most common causes of premature death and morbidity and have a major impact on health-care costs, productivity, and growth. Cardiovascular disease, cancer, diabetes, and chronic respiratory disease have been prioritized in the Global NCD Action Plan endorsed by the World Health Assembly, because they share behavioral risk factors amenable to public-health action and represent a major portion of the global NCD burden. Chronic kidney disease (CKD) is a key determinant of the poor health outcomes of major NCDs. CKD is associated with an eight- to tenfold increase in cardiovascular mortality and is a risk multiplier in patients with diabetes and hypertension. Milder CKD (often due to diabetes and hypertension) affects 5-7% of the world population and is more common in developing countries and disadvantaged and minority populations. Early detection and treatment of CKD using readily available, inexpensive therapies can slow or prevent progression to end-stage renal disease (ESRD). Interventions targeting CKD, particularly to reduce urine protein excretion, are efficacious, cost-effective methods of improving cardiovascular and renal outcomes, especially when applied to high-risk groups. Integration of these approaches within NCD programs could minimize the need for renal replacement therapy. Early detection and treatment of CKD can be implemented at minimal cost and will reduce the burden of ESRD, improve outcomes of diabetes and cardiovascular disease (including hypertension), and substantially reduce morbidity and mortality from NCDs. Prevention of CKD should be considered in planning and implementation of national NCD policy in the developed and developing world.

The availability and affordability of selected essential medicines for chronic diseases in six low- and middle-income countries

OBJECTIVE To assess the availability and affordability of medicines used to treat cardiovascular disease, diabetes, chronic respiratory disease and glaucoma and to provide palliative cancer care in six low- and middle-income countries. METHODS A survey of the availability and price of 32 medicines was conducted in a representative sample of public and private medicine outlets in four geographically defined areas in Bangladesh, Brazil, Malawi, Nepal, Pakistan and Sri Lanka. We analysed the percentage of these medicines available, the median price versus the international reference price (expressed as the median price ratio) and affordability in terms of the number of days wages it would cost the lowest-paid government worker to purchase one month of treatment. FINDINGS In all countries<or=7.5% of these 32 medicines were available in the public sector, except in Brazil, where 30% were available, and Sri Lanka, where 28% were available. Median price ratios varied substantially, from 0.09 for losartan in Sri Lanka to 30.44 for aspirin in Brazil. In the private sector in Malawi and Sri Lanka, the cost of innovator products (the pharmaceutical product first given marketing authorization) was three times more than generic medicines. One month of combination treatment for coronary heart disease cost 18.4 days wages in Malawi, 6.1 days wages in Nepal, 5.4 in Pakistan and 5.1 in Brazil; in Bangladesh the cost was 1.6 days wages and in Sri Lanka it was 1.5. The cost of one month of combination treatment for asthma ranged from 1.3 days wages in Bangladesh to 9.2 days wages in Malawi. The cost of a one-month course of intermediate-acting insulin ranged from 2.8 days wages in Brazil to 19.6 in Malawi. CONCLUSION Context-specific policies are required to improve access to essential medicines. Generic products should be promoted by educating professionals and consumers, by implementing appropriate policies and incentives, and by introducing market competition and/or price regulation. Improving governance and management efficiency, and assessing local supply options, may improve availability. Prices could be reduced by improving purchasing efficiency, eliminating taxes and regulating mark-ups.

Adherence to cardiovascular therapy: a meta-analysis of prevalence and clinical consequences

AIMS The aim of this study was to determine the extent to which adherence to individual vascular medications, assessed by different methods, influences the absolute and relative risks (RRs) of cardiovascular disease (CVD) and all-cause mortality. METHODS AND RESULTS We performed a systematic review and meta-analysis of prospective epidemiological studies (cohort, nested case-control, or clinical trial) identified through electronic searches using MEDLINE, Web of Science, EMBASE, and Cochrane databases, involving adult populations (≥ 18 years old) and reporting risk estimates of cardiovascular medication adherence with any CVD (defined as any fatal or non-fatal coronary heart disease, stroke or sudden cardiac death) and/or all-cause mortality (defined as mortality from any cause) outcomes. Relative risks were combined using random-effects models. Forty-four unique prospective studies comprising 1 978 919 non-overlapping participants, with 135 627 CVD events and 94 126 cases of all-cause mortality. Overall, 60% (95% CI: 52-68%) of included participants had good adherence (adherence ≥ 80%) to cardiovascular medications. The RRs (95% CI) of development of CVD in those with good vs. poor (<80%) adherence were 0.85 (0.81-0.89) and 0.81 (0.76-0.86) for statins and antihypertensive medications, respectively. Corresponding RRs of all-cause mortality were 0.55 (0.46-0.67) and 0.71 (0.64-0.78) for good adherence to statins and antihypertensive agents. These associations remained consistent across subgroups representing different study characteristics. Estimated absolute risk differences for any CVD associated with poor medication adherence were 13 cases for any vascular medication, 9 cases for statins and 13 cases for antihypertensive agents, per 100 000 individuals per year. CONCLUSION A substantial proportion of people do not adhere adequately to cardiovascular medications, and the prevalence of suboptimal adherence is similar across all individual CVD medications. Absolute and relative risk assessments demonstrate that a considerable proportion of all CVD events (~9% in Europe) could be attributed to poor adherence to vascular medications alone, and that the level of optimal adherence confers a significant inverse association with subsequent adverse outcomes. Measures to enhance adherence to help maximize the potentials of effective cardiac therapies in the clinical setting are urgently required.

WHO study on Prevention of REcurrences of Myocardial Infarction and StrokE (WHO-PREMISE)

OBJECTIVE To determine the extent of secondary prevention of coronary heart disease (CHD) and cerebrovascular disease (CVD) in low- and middle-income countries. METHODS A descriptive cross-sectional survey of a sample of 10 000 CHD (85.2%) and CVD (14.8%) patients (6252 men; 3748 women) was conducted over 6 months in geographically defined areas. The mean age was 59.2 years (standard deviation (SD), 10.8). Consecutive patients were recruited from a stratified random sample of primary, secondary and tertiary care facilities in defined areas in 10 countries (Brazil, Egypt, India, Indonesia, Islamic Republic of Iran, Pakistan, Russian Federation, Sri Lanka, Tunisia and Turkey). The main outcome measures were levels of lifestyle and physiological risk factors, and the use of drugs for secondary prevention of CHD and CVD. FINDINGS Approximately 82%, 89% and 77% of patients were aware of the cardiovascular benefits of quitting smoking, a heart-healthy diet and regular physical activity, respectively. About half (52.5%) engaged in less than 30 minutes of physical activity per day, 35% did not follow a heart-healthy diet and 12.5 % were current tobacco users. Blood pressure had been measured in 93.8% (range 71-100%), blood cholesterol in 85.5% (range 29-97%) and blood sugar in 75.5% (range 65-99%) in the preceding 12 months. The proportions who had received medications among CHD and CVD patients were: aspirin, 81.2%, 70.6%; beta-blockers, 48.1%, 22.8%; angiotensin-converting enzyme inhibitor, 39.8%, 37.8%; statins, 29.8%, 14.1%, respectively. About one-fifth of patients with CHD had undergone revascularization. CONCLUSION A significant proportion of patients did not receive appropriate medications. About 47% of patients had at least two or more modifiable risk factors (smoking, physical inactivity, hypertension, diabetes or hypercholesterolaemia). There are considerable missed opportunities for prevention of recurrences in those with established CVD in low- and middle-income countries.

Non-communicable diseases in the Arab world

According to the results of the Global Burden of Disease Study 2010, the burden of non-communicable diseases (cardiovascular disease, cancer, chronic lung diseases, and diabetes) in the Arab world has increased, with variations between countries of different income levels. Behavioural risk factors, including tobacco use, unhealthy diets, and physical inactivity are prevalent, and obesity in adults and children has reached an alarming level. Despite epidemiological evidence, the policy response to non-communicable diseases has been weak. So far, Arab governments have not placed a sufficiently high priority on addressing the high prevalence of non-communicable diseases, with variations in policies between countries and overall weak implementation. Cost-effective and evidence-based prevention and treatment interventions have already been identified. The implementation of these interventions, beginning with immediate action on salt reduction and stricter implementation of tobacco control measures, will address the rise in major risk factors. Implementation of an effective response to the non-communicable-disease crisis will need political commitment, multisectoral action, strengthened health systems, and continuous monitoring and assessment of progress. Arab governments should be held accountable for their UN commitments to address the crisis. Engagement in the global monitoring framework for non-communicable diseases should promote accountability for effective action. The human and economic burden leaves no room for inaction.

Organizational Update The World Health Organization Global Status Report on Noncommunicable Diseases 2014; One More Landmark Step in the Combat Against Stroke and Vascular Disease

Most countries are likely to fail to meet global targets on tackling noncommunicable diseases (NCDs), according to the second Global Status Report on Noncommunicable Diseases 2014 released by the World Health Organization on January 19, 2015. ‘Attaining the nine global NCD targets; a shared responsibility’ is the theme of this global report. The report aims to inform Ministries of Health and all stakeholders of the progress made on targets set in 2013, 2 years after world leaders agreed to tackle this global health problem at a United Nations high-level meeting. In May 2013, the World Health Assembly adopted a global NCD action plan monitoring framework with 25 indicators and 9 voluntary global targets set for 2025. According to the latest statistics in the report, NCDs continue to be the leading cause of deaths worldwide and were responsible for 38 million of the world’s 56 million deaths in 2012. An estimated 17.5 million NCD deaths were caused by cardiovascular disease, including 6.7 million from strokes. Some 16 million of NCD deaths occurred in people …

The Contribution of the Framingham Heart Study to the Prevention of Cardiovascular Disease: A Global Perspective

The Framingham Heart Study has been a trailblazer in the field of cardiovascular epidemiology. The wealth of novel scientific data that it has generated over 5 decades has made a significant contribution to cardiovascular disease (CVD) prevention in the United States and indirectly influenced global CVD prevention strategies. The Framingham Study has provided insights into the prevalence, incidence, prognosis, predisposing factors, and determinants of CVD. The now well-established risk factor concept, fundamental to prevention of CVD, originated from the Framingham study. It generated seminal findings such as the effects of tobacco use, unhealthy diet, physical inactivity, obesity, raised blood cholesterol, raised blood pressure, and diabetes on CVD. When these findings were first published, these were novel cardiovascular risk factors, now they are the major focus for global and national prevention efforts for reducing the burden of CVD and other major noncommunicable diseases. The Framingham Heart Study has also been in the forefront of the development of cardiovascular risk prediction equations for assessment of absolute risk. Further developments in this area including the development of World Health Organization/International Society of Hypertension risk prediction charts have resulted in a paradigm shift in CVD prevention strategies, from a single risk factor focus to a more cost-effective total cardiovascular risk approach, an approach recommended by the World Health Organization for CVD prevention worldwide.

Total cardiovascular risk approach to improve efficiency of cardiovascular prevention in resource constrain settings

OBJECTIVES To determine the population distribution of cardiovascular risk in eight low- and middle-income countries and compare the cost of drug treatment based on cardiovascular risk (cardiovascular risk thresholds ≥ 30%/≥ 40%) with single risk factor cutoff levels. STUDY DESIGN AND SETTING Using World Health Organization (WHO) and the International Society of Hypertension risk prediction charts, cardiovascular risk was categorized in a cross-sectional study of 8,625 randomly selected people aged 40-80 years (mean age, 54.6 years) from defined geographic regions of Nigeria, Iran, China, Pakistan, Georgia, Nepal, Cuba, and Sri Lanka. Cost estimates for drug therapy were calculated for three countries. RESULTS A large fraction (90.0-98.9%) of the study population has a 10-year cardiovascular risk <20%. Only 0.2-4.8% are in the high-risk categories (≥ 30%). Adopting a total risk approach and WHO guidelines recommendations would restrict unnecessary drug treatment and reduce the drug costs significantly. CONCLUSION Adopting a total cardiovascular risk approach instead of a single risk factor approach reduces health care expenditure by reducing drug costs. Therefore, limited resources can be more efficiently used to target high-risk people who will benefit the most. This strategy needs to be complemented with population-wide measures to shift the cardiovascular risk distribution of the whole population.

Cardiovascular risk management and its impact on hypertension control in primary care in low-resource settings: a cluster-randomized trial

OBJECTIVE To evaluate a simple cardiovascular risk management package for assessing and managing cardiovascular risk using hypertension as an entry point in primary care facilities in low-resource settings. METHODS Two geographically distant regions in two countries (China and Nigeria) were selected and 10 pairs of primary care facilities in each region were randomly selected and matched. Regions were then randomly assigned to a control group, which received usual care, or to an intervention group, which applied the cardiovascular risk management package. Each facility enrolled 60 consecutive patients with hypertension. Intervention sites educated patients about risk factors at baseline and initiated treatment with hydrochlorothiazide at 4 months in patients at medium risk of a cardiovascular event, according to a standardized treatment algorithm. Systolic blood pressure change from baseline to 12 months was the primary outcome measure. FINDINGS The study included 2397 patients with baseline hypertension: 1191 in 20 intervention facilities and 1206 in 20 control facilities. Systolic and diastolic blood pressure decreased more in intervention patients than in controls. However, at 12 months more than half of patients still had uncontrolled hypertension (systolic blood pressure > 140 mmHg and/or diastolic blood pressure > 90 mmHg). Behavioural risk factors had improved among intervention patients in Nigeria but not in China. Only about 2% of hypertensive patients required referral to the next level of care. CONCLUSION Even in low-resource settings, hypertensive patients can be effectively assessed and managed in primary care facilities.