Chronic diseases and calls to action

Hold the front page! ‘Chronic diseases, principally cardiovascular diseases (CVDs), cancer, chronic respiratory diseases, and diabetes, are leading causes of death and disability but are grossly neglected on the global-health agenda’ announced the Lancet on 8 December 2007.1 This was true 2 years ago in 2005 when the Lancet highlighted the general neglect of chronic diseases in the face of Millennium Development Goals resolutely focused on child and maternal survival.2, 3 Indeed chronic diseases have topped infectious diseases in the global death league since the first report from the global burden of disease project in 1990.4 An important but completely neglected aspect of the discussion is that the rise in chronic disease burden represents an increase in the population at risk resulting from successful implementation of maternal and child health programmes in the developing world—a theme I will return to. Will a campaign of ‘international science advocacy’ led by the Chronic Disease Action Group5—a collaboration between the Lancet and scientists from WHO and a wide range of countries—succeed in preventing chronic disease and saving lives? First, I should declare my interests, both as a chronic disease epidemiologist working in both developed and developing countries and as a member of the Chronic Disease Action Group, in seeing the campaign succeed. The science platform for advocacy was built on WHO's 2005 publication Preventing chronic disease: a vital investment6 which proposed that we know sufficient about the causes of the major chronic diseases and we have effective means of prevention and treatment to proceed to strong advocacy for changes in priority setting in developing countries and reallocation of resources towards chronic disease prevention. The basic arguments for making the prevention and control of chronic diseases were spelt out in a series of Lancet articles published in 20057–10 and centred on four themes: the burden of disease attributable to chronic diseases is dominant and rising in low- and middle-income countries; these diseases hit younger people at the peak of their productive lives; health systems cannot be made for each disease but need to be integrated to meet all health needs; and, finally, there are cost-effective interventions available that, if implemented, would save lives, reduce suffering and poverty. Notwithstanding the lack of basic elements of censuses, death registration and attribution of causes of death in many low-income countries a consensus has emerged, led by the Global Burden of Disease group over the last decade, that we can be generally assured that chronic diseases are common causes of death and disability, even in the poorest countries.11 The evidence that intervention improves outcomes is extremely strong for anti-hypertensive and cholesterol-lowering drug treatments in those at high risk of coronary heart disease and ischaemic stroke.12 Aspirin is also of benefit in those who have suffered clinical events and has a role in those at high cardiovascular risk.13 However, in developing country populations where haemorrhagic stroke makes up a substantial proportion of the cardiovascular disease burden, the cost-effectiveness of aspirin will differ and remains to be evaluated in detail. Evidence for chronic disease health protection through legislation, fiscal and other population-targeted means is strong in the areas of tobacco control14 but drops to the level of case studies once food and physical activity come into focus. All this has been well known for over a decade. So what is new? First, WHO have re-emphasized their 2005 global goal of reducing chronic diseases by 2% every year between 2005 and 2015. Achieving this will avert 36 million deaths.11 It is now 2008 and the clock has been ticking but, so far no deaths appear to have been averted, so countries interested in taking up the challenge of meeting the goal will now have to upgrade their efforts by 20% to hit the target. Setting goals is a helpful strategy as it affirms a direction of travel and once goals have been collectively accepted, implies that the means to achieve them will be found. But global goals are a bit like a global New Year's resolution—much easier to make than to keep. Moreover, unlike climate change or international trade agreements—where global action is the only way forward—the opportunities for ‘global’ action on health are much more constrained, as even a cursory review of the implementation of the WHO Framework Convention on Tobacco Control shows—readily signed in a majority of countries, but taken no further than this stage in many. In Europe, where there is no misunderstanding about its intent, proper implementation of relevant measures such as smoking in public places remains a political ‘no go zone’ in several countries. Second, we have a prescription for health protection that is part old—implementation of part of the WHO Framework on Tobacco—and part new, a voluntary reduction by manufacturers in the salt content of processed foods and condiments, and a mass media campaign on reducing added salt for the population at large.14 The tobacco interventions (increases in the price of tobacco, enforcement of smoke-free workplaces, packaging and labelling changes, public awareness campaigns and a comprehensive ban on advertising, promotion and sponsorship) are expected to reduce smoking prevalence by about 20% and the salt interventions should reduce intake by 15%. Taken together, these interventions would realize 13.8 million deaths delayed in 23 low- and middle-income countries used in the modelling exercise (these were selected on the basis availability of data and collectively they represent 80% of the global burden of chronic diseases in the developing world) and would cost about half a US dollar per person per year. An unpalatable truth for the Chronic Disease Action Group is that there is no easily written ‘prescription’ for health protection. The necessary and sufficient dose of mass media is unknown for specific contexts, the means of political engagement with governments and industries provide almost infinite variations of opportunity and challenge, and the strength of opposition from the vested interests of the tobacco and food industries will be hard to overcome. Third, on the prevention side, things look rosier from an evidence perspective. This is all about prescriptions of well-known drugs at known doses for people with known levels of high CVD risk. A combination of effective drugs is proposed—comprising aspirin, a statin and two blood pressure-lowering drugs along the lines originally proposed in 2001.15 A combination single pill, or the Polypill©,16 which contains folic acid in addition to the other drugs, was not considered a necessary prerequisite on the grounds that an appropriate formulation does not exist and debates about which drugs at which doses would undoubtedly slow up implementation. It should be noted that CIPLA Ltd. India claim to have produced a range of combination pills (Dr YK Hamied, personal communication) that might improve compliance compared with taking four different pills each day. Although contribution of folate to CHD prevention has been subject to considerable doubt,17 more recent evidence suggests that in countries with folate poor diets and in places where ischaemic stroke is common, there may be a role of folic acid supplementation after all,18 although the possible increased risk of some cancers may offset potential benefits. The combination of drugs scores highly in delivering just under 18 million deaths delayed at an average cost of US$1 per person per year.12 The overall reasoning is that achieving the global goal of a 2% annual reduction in chronic diseases can be done by implementing these two lines of attack—health protection and disease prevention using these recommended methods at a cost of about US$ 5.8 billion a year in the 23 countries considered. This amount represents about 3% of the UK National Health Service annual budget, about 50% of UK Department for International Development's annual spending and about 25% of India's military spending. Doing nothing will result in an estimated US$84 billion in lost economic production from CHD, stroke and diabetes alone in these countries over 10 years, whereas the economic gain from the deaths averted amounts to US$8 billion over the same time period. So what is holding us back from taking action? Were we waiting for the data contained in the Lancet's chronic diseases suite of four papers and the call to collective action? Are the arguments now more persuasive than they were first time around? As my first contribution to advocacy for the Chronic Disease Action Group I will set the scene for an analysis of the potential reasons for inactivity from a range of different viewpoints: country governments, WHO, public health scientists and activists, clinicians and patient groups. Certainly, the economic costs of doing nothing sound like a lot of lost productivity, but the economic gains (US$8 billion) do not stack up against the cost of intervention (US$58 billion). So I foresee problems getting to first base with the Treasury ministers in many developing countries. The scientists have taken the view that anything costing less than three times the gross national income per head per disability life year delayed is cost-effective but this, of course, ignores the reality of public sector budget allocations that have no head-room for innovation. Reallocation is easy to say but rather difficult to achieve in countries that are spending only 2–3% of gross national income on public health services. In countries, like India, that are enjoying dramatic economic growth, there is a strong argument that spending more on ‘effective’ public health interventions is not a luxury but might provide a means of reducing health inequalities associated with the spread of adverse risk factor profiles from the advantaged middle classes to the less educated and more vulnerable sections of society. At a June 2007 Wellcome Trust/WHO meeting to discuss secondary prevention of chronic diseases, clinicians working in South Africa found discussions about preventing CVD difficult to square with their direct experience in busy hospitals seeing myriad forms of infectious disease affecting children and adults alike. Of course, the hospital clinical perspective is but the tip of the iceberg of the clinical manifestations of disease. But if the vocal clinical staff of teaching hospitals and district hospitals do not feel the problem of chronic diseases is ‘real’ we have a credibility problem. In turn, this generates negative advocacy that will be used to cancel out very effectively any positive advocacy for chronic disease prevention. We need to include clinicians in the call to action at every level of the health system by ensuring that they understand the data and act accordingly. We need to help doctors and nurses in developing countries to change their own health behaviours, help patients with theirs and act as advocates for social change. Lenny Bruce, the infamous stand-up comedian and social critic, was famous for shouting this from the stage of his New York cabaret acts in the 1960s. The Lancet reports speak in terms of deaths averted—that is postponed—rather than prevented although ‘delayed’ might be better understood. In the long run, everyone dies of something. An unmentioned issue here is ageism. Chronic diseases, so people believe, affect people who are old and not children, who do not have their whole lives before them. And older lives are not worth as much as younger lives and dying from CVD or cancer is quicker (and cheaper) than dying from dementia and multiple organ failure, so the reasoning goes. So doing nothing specific, maintaining the status quo of family responsibility and support for chronic diseases is just fine. Here the Lancet reports do have important ammunition to defeat these arguments. Nearly four-fifths of the projected life-years gained in low- and middle-income countries between 2005 and 2015 would come from deaths delayed in people under 70 years of age.11 Intriguingly, the projections presented indicate that despite marked population ageing over the next decade, the proportion of chronic disease deaths occurring in people over age 70 years will fall. This seems unlikely. The Lancet, along with other journals, has issued quite a number of such calls in the last few years (Figure 1), and has asked once whether the call had been effective.19 In this case, although acknowledging that measuring the effect of a series of articles on policy and practice is not possible, intermediate goals had been achieved. One wonders whether this represents a publication bias given that the question of impact was not asked for the other 13 calls to action since 1987. The rise in calls to action may actually be having a disempowering effect as scientists and practitioners—whose main jobs are not advocacy—cannot be expected to get excited about each call without disengaging from some other activity. One of the very earliest calls to action concerning infant mortality in America, published by the Lancet in 1911,20 merits re-issuing given the falling international ranking of USA in terms of its infant mortality rate, 37th out of 194 countries in 2005.21 The real challenge for any call to action is to develop and implement a plan for achieving its goals. Calls to action published in medical journals: 1966–2007. Source: Medline Science is nuanced in its language and avoids over-strong conclusions from less than robust data. Advocacy requires a clear, simple and consistent message, and with the exception of much of the tobacco control messages, simplification of the message hides the subtlety. Interpretation of the scientific data is rather more problematic than the articles in the Lancet 2007 series would suggest. The average estimates for the 23 countries hide dramatic variability both in the likely outcomes that might be expected and the costs of implementing the same interventions. Developing countries are not all at the same starting line, and some of them—such as Russia—would not consider themselves in the same boat as others—such as Bangladesh. Aggregating at an almost global level produces large headline figures of lives averted and economic costs saved, but lacks direct relevance to national and state governments where the prevention game will be played. Gaziano and colleagues22 are charitably disposed to the North Karelia study and suggest that as a front runner study it found a bigger effect than other, subsequent studies found—which they explain as due to the virgin field that had not been tilled by any sort of intervention. Subsequent studies would have to make their comparisons against a background of downward drift of risk factors fuelled by a general climate of health promotion messages. This is a nice idea, but ignores several important facts: (i) the North Karelia study was not a randomized experiment but many of the subsequent studies were randomized and better able to control for selection factors and confounding; (ii) the control region of Kuopio showed almost identical risk factor changes from the outset; and (iii) the mortality rates for the counties of the whole country showed parallel declines, with North Karelia showing the highest rates in the 1960s and the highest rates in the 1980s. Perhaps the most important fact is that North Karelia was one of a family of studies mounted with WHO support at the same time in different countries and only the North Karelia study ever formally published findings. The null results for the other quasi-experiments were relegated to a small section in a WHO pamphlet long lost and forgotten.23, 24 High-profile publication of the site-specific positive finding—as was done with the Belgium arm of the randomized WHO Factories cardiovascular disease prevention study25—is dangerous, as in this case, full publication of all the study sites showed no impact of health promotion.26 We would now consider such publication bias—suppression of negative findings—a neglect of scientific duty, but those were different times. When it comes to the randomized trial evidence for multi-factorial intervention, both co-editors of this journal were responsible for conducting a systematic review of the evidence a decade ago, which despite involving over 130 000 people, was unable to detect any substantive effect on CHD mortality, but owing to imprecision of the estimate of effect, could not exclude an effect as big as a 10% reduction in mortality. An updated review, involving 12 000 more participants in 30 further randomized trials is nearing completion and, sad to say, enthusiasm for conducting large enough trials to provide statistical power for clinical events has been wanting. One of the perplexing issues in this review was the small but discernable effects of health promotion interventions on risk factors: a 2.5 mmHg fall in diastolic blood pressure, a 0.1 mmol/l reduction in total cholesterol and a 4% reduction in smoking. If these were real effects, rather than artefacts produced by failures to blind participants and outcome assessors for blood pressure measurement, lack of cotinine bioassay of smoking and better to effective CVD drug treatments in the intervention other it would be to what of effect on CVD mortality would be the reduction in diastolic blood pressure alone would be expected to a 10% reduction in CHD mortality and over a reduction in stroke of this were not and would have been to be in a of trials of this by the lack of effect in randomized trials of health Gaziano and data from and the only evidence in support of a in disease is a analysis of recent CHD in In this changes in the disease with the that they were the of the in risk. evidence is and a more So where are we The Lancet to is not the only game in a large US health has set up a through its to for chronic disease in the developing This has successful with a large number of a few of which are in the of The Global was with a report of a involving the policy and in chronic This is between the Health UK of Health of and US National of the of in the this set of are not the Global were by the which suggests that any that might have been by is in of an for the increase in chronic diseases, is a of the of the efforts of to improve economic and social Perhaps a more to getting the control and prevention of chronic diseases the of developing countries would be to and their in maternal and child to this the of many countries in major infectious diseases and the of of health this we should be means of health systems in their to provide family health and both and This will of programmes for into forms of Setting up chronic disease programmes will an that has the of the health system to effectively in many countries. 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