Comment
Stemming the global tsunami of cardiovascular disease Over the past 30 years, cardiovascular disease has increased in incidence in low-income and middle-income countries, while cardiovascular disease has declined in several high-income countries.1,2 The major modifiable risk factors for cardiovascular disease are known, and their impact is similar in most regions of the world.3,4 In The Lancet, the Global Burden of Metabolic Risk Factors of Chronic Diseases Collaborating Group5–7 presents three reports that describe global population-level changes in body-mass index (BMI), systolic blood pressure, and total cholesterol over three decades. The researchers grouped data from each country into 21 subregions and by per-capita income status. Regional data help to inform about disease trends in neighbouring countries, and the income classification is also useful.8 The researchers extracted the average BMI, fasting total cholesterol, and systolic blood pressure for men and women from published and unpublished reports. When average values were not reported, they developed linear regression models to estimate means by using reported prevalences of risk factors, because the two correlate with each other.9 They also accounted for differences in sample sizes across studies by applying variance weights. They then developed Bayesian hierarchical models to estimate risk-factor changes over time, by age, sex, and country, and also accounted for country income, urban versus rural status, and national availability of food types, because these factors affect population levels of the three risk factors. The models used prior information (riskfactor levels and trends by country), and incorporated information about the uncertainty of the estimates, to calculate the posterior distribution of model parameters, which in turn were used to obtain the mean value for each risk factor at specific times, and trends by age group, country, and year. Despite in-depth data collection, and sophisticated statistical analyses, the Collaborating Group’s efforts were limited by the scant data for cholesterol and blood pressure available from low-income and middle-income countries, which made estimates from these regions less robust. Furthermore, due to the limited availability of data on drug use and some dietary exposures (including salt intake), the Group was unable to determine their influence on trends in cholesterol and blood pressure. www.thelancet.com Vol 377 February 12, 2011
The Collaborating Group reports that, in adult men and women, obesity is increasing in all regions of the world. In 2008, 1·46 billion adults were overweight (BMI ≥25 kg/m²), including 500 million who were obese (BMI ≥30 kg/m²). This result suggests that overweight affects one in three adults and obesity affects one in nine adults in the world—a tsunami of obesity that will eventually affect all regions of the world. BMI was substantially higher in high-income countries (mean BMI [kg/m²] 24·7 in 1980 and 26·6 in 2008) and in middle-income countries (23·6 and 26·1) compared with that in low-income countries (20·7 and 22·3), but increased in all regions, so that BMI is now similar in high-income and middle-income countries (figure). Trends in central adiposity were not considered because of a lack of population-based data. For systolic blood pressure, the researchers estimated that in 2008 there were 1 billion individuals with uncontrolled hypertension (systolic ≥140 or diastolic ≥90 mm Hg). Surprisingly, blood pressure declined globally over three decades. In 1980 the mean systolic pressure was highest in individuals from high-income countries compared with those from middle-income countries and low-income countries. However, between 1980 and 2008, mean systolic pressure declined markedly in high-income countries (by 7·3 mm Hg) whereas it increased in lowincome countries (by 3·3 mm Hg), with little overall change in middle-income countries. The greatest falls in systolic pressure were in North America, Australasia, and western Europe. Increases in systolic pressure occurred in some middle-income countries and low-income countries, including subregions of Oceania, east Africa, south Asia, southeast Asia, and west Africa. Fasting total cholesterol concentrations were highest in high-income countries in 1980 and 2008 (5·62 and 5·19 mmol/L), followed by middle-income countries (4·91 and 4·70) and low-income countries (4·46 and 4·20). The greatest decreases occurred in western high-income countries, and in eastern and central Europe (0·2 mmol/L per decade). By contrast, increases in cholesterol occurred in east and southeast Asia and Pacific subregions (0·08–0·09 mmol/L per decade). Notably Japan, China, and Thailand all showed increases in total cholesterol. Although there is some non-uniformity in the changes in risk factors between countries within an economic
Published Online February 4, 2011 DOI:10.1016/S01406736(10)62346-X See Editorial page 527 See Articles pages 557, 568, and 578
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category, some general trends emerge (figure). Why is there a dissociation between the rise in BMI in all Mean BMI 28 27
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Figure: Change over time in mean BMI, systolic blood pressure, and total cholesterol by countries’ income category BMI is increasing in all three economic categories. In high-income countries, blood pressure and total cholesterol are decreasing. In middle-income countries, there is no major change in blood pressure and total cholesterol is decreasing. In low-income countries, blood pressure is increasing and total cholesterol is decreasing.
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economic regions, while there is a fall in blood pressure and cholesterol, especially in high-income countries? Why is there little increase in blood pressure and a decrease in cholesterol in middle-income countries, despite a clear increase in BMI? Why is there only an increase in blood pressure, but not in cholesterol in lowincome countries despite increases in BMI? Do these divergent trends mean that we can rapidly mitigate the adverse effects of increasing weight on blood pressure and total cholesterol through other means? Some of the impact of increasing obesity in high-income countries (and to some extent in middle-income countries) might be mitigated by better blood pressure control, and increased use of drugs to lower blood pressure and statins (eg, with a low-cost and low-dose polypill).10,11 But the decline in cholesterol predates the widespread use of statins in most of the world, and their use remains extremely low, even in secondary prevention in most countries. A decline in sodium intake (in some high-income countries such as Finland and Japan) might have contributed to falling blood pressure in some countries, but necessary information is not available from most countries on the rates of drug use or on changes in dietary and activity patterns. Understanding the reasons for the contrasting changes in obesity, blood pressure, and total cholesterol will provide useful insights that could help to mitigate the adverse effects of the epidemic of obesity more rapidly than the necessary societal and structural changes needed to reverse the prevalence of obesity itself. The trends in risk factors and cardiovascular disease rates described in most high-income countries are similar to the trends in risk factors in the USA over the past four decades.2 Systolic blood pressure and total cholesterol have decreased (despite increasing BMI), as have smoking rates. Changes in health behaviours, together with wider use of simple, lowcost, and effective therapies, seem to explain the marked fall in cardiovascular disease rates in the USA.2 These observations (within the USA and the contrasting patterns of obesity vs blood pressure and total cholesterol described by the Collaborating Group) suggest that directly controlling blood pressure, total cholesterol, and smoking will lead to rapid and substantial reductions in cardiovascular disease rates even while obesity (and diabetes) might be increasing.12,13 Therefore focusing on controlling these www.thelancet.com Vol 377 February 12, 2011
Comment
three risk factors (blood pressure, total cholesterol, and smoking) will rapidly and to a large extent reduce cardiovascular disease globally within a few years, while we continue our efforts to stem and ultimately reverse the tide of obesity, which will need more prolonged and societal-based interventions over decades. Considering all risk-factor trends together, the forecast for cardiovascular disease burden in low-income and middle-income countries over the next few decades is dismal and comprises a population emergency that will cost tens of millions of preventable deaths, unless rapid and widespread actions are taken by governments and health-care systems worldwide. Although preventive and treatment strategies with drug and technological solutions or individualised counselling to modify health behaviours are effective, sole reliance on these approaches will create an unsustainable financial burden both on individuals and societies worldwide. There is an urgent need to understand why unhealthy behaviours are adopted by both individuals and communities, and how they affect metabolic risk factors and smoking, to develop strategies that prevent the development of the “causes” (likely social and economic drivers) of the “causes” (the established risk factors) of cardiovascular disease.14 Globalisation, characterised by increased economic growth, foreign direct investment, market integration, and urbanisation, will continue to have a broad impact on health behaviours (diet, physical activity, tobacco consumption) and are strongly correlated to the development of cardiovascular disease and other chronic diseases.8 Ironically the economic growth of low-income and middle-income countries is now threatened by the projected cardiovascular disease epidemic. In the long term, the most effective means of stemming the tsunami of cardiovascular disease globally is through population-level risk-factor control, whereby the population average of a given risk factor is reduced.6 In high-income countries, the reductions in key cardiovascular disease risk factors at the population level are attributable to changes in the food supply (ie, reduction in animal products and sodium consumption), and through increased physical activity.15 However, given that macroeconomic and macrosocial factors influence the pattern of food consumption, sedentariness, and decrease in utilitarian activity secondary to changes in the types of occupation, transportation, and automation at work and home, the www.thelancet.com Vol 377 February 12, 2011
solutions for population-level risk-factor control in all countries, especially in middle-income and low-income countries, will be complex and will take time. Developing solutions will require novel and as yet unavailable data to shed light on the complex interactions between agricultural and food policies (which affect the costs and promotion of different types of foods), industrialisation (the nature of jobs), transportation, urban design, community architecture (which affects the expenditure of energy during utilitarian activity), economic changes, and social and cultural values, all of which influence health behaviours and which ultimately affect cardiovascular risk factors and cardiovascular disease (and several other related chronic diseases). Health-related research cannot be separated from research into policies related to agriculture, trade, education, taxation, and urban design, and political solutions across these sectors are needed to ensure that the health of a nation’s people is a top priority. However, a recent analysis of 23 low-income and middle-income countries indicated that the capacity of these countries to effectively deal with the existing and projected burden of non-communicable diseases (without neglect of the relevant communicable diseases) is limited.16 For most low-income and middle-income countries, joint programmes in which both common communicable and non-communicable diseases are prevented and controlled are necessary. The choice between prioritising the control of communicable or non-communicable diseases is artificial. What is needed is to develop integrated teams and systems with the capacity to tackle the common health problems of each country. This integrated approach requires expanding the paradigm of health care beyond traditional physicians and nurses, to involve grassroots organisations, school teachers, and trained health-care workers. Indeed, such an approach was responsible for the near global eradication of poliomyelitis.17 Such a major transformation of systems of health care (ie, not just delivery of medical care) is possible but will require political leadership that truly understands that the control of all diseases, including non-communicable diseases, is inextricably linked to the prosperity of all nations of the world. The solution to the predicted global epidemic of cardiovascular disease was succinctly stated by Geoffrey Rose: “Mass diseases and mass exposures require mass remedies.”9 Mass remedies require the masses to be part of the solution. We hope 531
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that a high-level commitment to mass remedies for cardiovascular disease will be made by world leaders at the UN General Assembly on chronic non-communicable diseases in September, 2011.18
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Sonia S Anand, *Salim Yusuf Population Health Research Institute, McMaster University and Hamilton Health Sciences, ON, Canada; and Departments of Medicine and Epidemiology, McMaster University, Hamilton, ON, Canada L8L 2X2 yusufs@mcmaster.ca SSA holds the May Cohen Eli Lilly Chair in Women’s Health Research and the Michael G DeGroote Heart and Stroke Foundation of Ontario Chair in Population Health. SY holds an endowed Heart and Stroke Foundation of Ontario Research Chair. We declare that we have no conflicts of interest. 1 2 3
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Reddy KS. Cardiovascular disease in non-Western countries. N Engl J Med 2004; 350: 2438–40. Ford ES, Ajani UA, Croft JB, et al. Explaining the decrease in U.S. deaths from coronary disease, 1980–2000. N Engl J Med 2007; 356: 2388–98. Yusuf S, Hawken S, Ounpuu S, et al, on behalf of the INTERHEART Study Investigators. Effect of potentially modifiable risk factors associated with myocardial infarction in 52 countries (the INTERHEART study): case-control study. Lancet 2004; 364: 937–52. O’Donnell MJ, Xavier D, Liu L, et al, on behalf of the INTERSTROKE investigators. Risk factors for ischaemic and intracerebral haemorrhagic stroke in 22 countries (the INTERSTROKE study): a case-control study. Lancet 2010; 376: 112–23. Danaei G, Finucane MM, Lin JK, et al, on behalf of the Global Burden of Metabolic Risk Factors of Chronic Diseases Collaborating Group (Blood Pressure). National, regional, and global trends in systolic blood pressure since 1980: systematic analysis of health examination surveys and epidemiological studies with 786 country-years and 5·4 million participants. Lancet 2011; published online Feb 4. DOI:10.1016/S0140-6736(10)62036-3. Finucane MM, Stevens GA, Cowan MJ, et al, on behalf of the Global Burden of Metabolic Risk Factors of Chronic Diseases Collaborating Group (Body Mass Index). National, regional, and global trends in body-mass index since 1980: systematic analysis of health examination surveys and epidemiological studies with 960 country-years and 9·1 million participants. Lancet 2011; published online Feb 4. DOI:10.1016/S0140-6736(10)62037-5.
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Farzadfar F, Finucane MM, Danaei G, et al, on behalf of the Global Burden of Metabolic Risk Factors of Chronic Diseases Collaborating Group (Cholesterol). National, regional, and global trends in serum total cholesterol since 1980: systematic analysis of health examination surveys and epidemiological studies with 321 country-years and 3·0 million participants. Lancet 2011; published online Feb 4. DOI:10.1016/S0140-6736(10)62038-7. Stuckler D. Population causes and consequences of leading chronic diseases: a comparative analysis of prevailing explanations. Milbank Q 2008; 86: 273–326. Rose G. Sick individuals and sick populations. Int J Epidemiol 2001; 30: 427–32. The Indian Polycap Study (TIPS). Effects of a polypill (Polycap) on risk factors in middle-aged individuals without cardiovascular disease (TIPS): a phase II, double-blind, randomised trial. Lancet 2009; 373: 1341–51. Lonn E, Bosch J, Teo KK, Pais P, Xavier D, Yusuf S. The polypill in the prevention of cardiovascular diseases: key concepts, current status, challenges, and future directions. Circulation 2010; 122: 2078–88. WHO. WHO report on the global tobacco epidemic, 2009: implementing smoke-free environments. 2009. http://whqlibdoc.who.int/publications/ 2009/9789241563918_eng_full.pdf (accessed Dec 28, 2010). International Diabetes Federation. World diabetes atlas, 4th edn. 2009. http://www.diabetesatlas.org (accessed Dec 28, 2010). Teo K, Chow CK, Vaz M, Rangarajan S, Yusuf S, the PURE Investigators-Writing group. The Prospective Urban Rural Epidemiology (PURE) study: examining the impact of societal influences on chronic noncommunicable diseases in low-, middle-, and high-income countries. Am Heart J 2009; 158: 1–7.e1. Capewell S, Ford ES, Croft JB, Critchley JA, Greenlund KJ, Labarthe DR. Cardiovascular risk factor trends and potential for reducing coronary heart disease mortality in the United States of America. Bull World Health Organ 2010; 88: 120–30. Alwan A, Maclean DR, Riley LM, et al. Monitoring and surveillance of chronic non-communicable diseases: progress and capacity in high-burden countries. Lancet 2010; 376: 1861–68. Oshinsky DM. Polio: an American story. Oxford: Oxford University Press, 2005. Beaglehole R, Horton R. Chronic diseases: global action must match global evidence. Lancet 2010; 376: 1619–21.
Securing the right to health for all in India Published Online January 12, 2011 DOI:10.1016/S01406736(10)62182-4 See Series page 587 See Series Lancet 2011; 377: 252, 332, 413, and 505 See Online/Series DOI:10.1016/S01406736(10)61888-0, DOI:10.1016/S01406736(10)61884-3, and DOI:10.1016/S01406736(10)61960-5
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The debates around securing the right to health for all in India are at a complex and sensitive stage. In India, we have gross inequity in health-care delivery. The huge inequity is evident, on the one hand, in flourishing international medical tourism, and high-technology biomedical interventions done cheaply, and, on the other, minimum levels of health care being unavailable to those unable to pay.1 The health status of people transcends the healthcare sector, and the social determinants of health, such as food, water, sewerage, and shelter, still elude large numbers of the poorest citizens in India. Between the early 1990s, when the process of economic reforms began, and now, the yearly per head consumption of
food grains in the country has drastically deteriorated.2 The latest National Family Health Survey (2005–06) provided grim evidence of very slow improvement in infant mortality, persistently low rates of child immunisation, and shocking rates of malnutrition.3 Inequity in social determinants of health and health care in a market-based system itself becomes a pathogenic factor that drives the engine of deprivation. Public awareness of the need to end inequities in the health status and health entitlements of the people is not new. As early as 1946, the Health Survey and Development Committee set forth a vision of health services in India based on equity, universality, and comprehensiveness of care.4 Actual progress in www.thelancet.com Vol 377 February 12, 2011