This anonymous essay was submitted to Open Philanthropy's Cause Exploration Prizes contest and posted with the author's permission.
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Summary
- Cardiovascular disease is the number one cause of mortality worldwide and an emerging health concern in low-income countries. As of 2019, the burden of DALYs due to cardiovascular disease in the developing world can be estimated to be 300 million per year.
- Demographic changes such as population growth and aging, as well as lifestyle changes due to rising incomes are likely to dramatically worsen the impact of cardiovascular disease in the developing world.
- Cardiovascular disease is highly preventable. Air pollution, tobacco use, unhealthy diet, and low physical activity are major environmental risk factors for CVD and can be tackled by societial and behavioral interventions.
- A number of studies have aimed to estimate the cost-effectiveness of interventions targeting CVD prevention. Many of these seem to be cost-effective to a degree in line with Open Philanthropy’s bar for desired impact.
- While policy advocacy seems to be the most cost-effective intervention, it may not be the most receptable for further funding. On the other hand, existing and future community interventions are likely to make use of additional funds.
Note: This essay is the result of a shallow literature-based research into cardiovascular disease, their impact, and possible solutions. Whenever the cost-effectiveness of interventions is discussed, numbers are directly taken from the literature without any adjustment for inflation (most of these results are therefore quoted in 2000 – 2010 dollars).
How big of a problem is cardiovascular disease in developing countries?
Low-income countries (LICs) struggle with low life expectancy and are mainly plagued by infectious diseases due to a lack of accessible medicine and healthcare. This is reflected in the fact that six out of the ten leading causes of death for people in LICs are communicable diseases, compared to just one in high-income countries (HICs).
However, as incomes rise and health systems become more developed, countries undergo a shift in the leading causes of death and disease. Once infectious diseases are brought under control, life expectancy rises and with this, diseases associated with aging become more prevalent. In parallel with this, the developing society undergoes other changes, such as increased urbanization and changing dietary habits that contribute to increased risks for non-communicable diseases, which make up for the majority of deaths in all other income groups besides LICs. This phenomenon is called epidemiological transition and has been observed repeatedly in countries all over the world.
The biggest killer amongst non-communicable diseases is cardiovascular disease (CVD), which is a group of conditions affecting the heart, including sudden cardiac arrest and stroke. In contrast to HICs where CVD is the number one cause of death, sub-Saharan Africa (SAA) still struggles mostly with nutritional and infectious diseases. Nonetheless, non-communicable diseases (NCDs) already account for about 35% of all deaths in the region, with CVD alone accounting for 13%. This indicates that SAA may be at a turning point of the epidemiological transition with contemporary double burden of disease from NCDs and infectious diseases.
The contribution of different CVDs still differs between LICs and HICs. While ischemic heart disease accounts for more than half of all cases in HICs, it represents less than 10% in SAA, where the most prevalent causes include hypertensive heart disease, cardiomyopathy, rheumatic heart disease, and congenital heart disease. Rheumatic heart disease is associated with bacterial infections and is therefore a representation of the remaining high burden of infectious disease in the region. However, both hypertensive heart disease and cardiomyopathy share a number of risk factors that are associated with the epidemiological transition, including obesity, diabetes and high blood pressure. Furthermore, as increases in these risk factors can be expected, ischemic heart disease and stroke which are caused by these same factors, are likely to rise in prevalence in SAA as well.
In terms of quantification, CVD is the number one cause of global mortality, amounting to about one third of all deaths worldwide. In the last three decades, the global prevalence of CVD almost doubled, reaching 523 million in 2019. Similarly, CVD mortality has risen by about 54% to 18.6 million in the same year. While population growth and aging are the major drivers for the global increase in total CVD, it is clear that CVD is a major global challenge.
The highest age-standardized rates for disability-adjusted life years (DALYs) are found in Central Asia, Eastern Europe and Oceania. Case numbers are likely to increase substantial in Northern Africa, Western Asia, Central and South Asia, Latin America, the Caribbean, and Eastern and Southeastern Asia, due to population growth and aging, with the share of older people projected to double between 2019 and 2050. LICs and lower middle-income countries (LMICs) experience 57% of global CVD deaths and 59% of DALY losses from CVD, as of 2017. This puts the total number of DALYs due to CVD in the developing world somewhere around 300 million in 2019.
While existing research on the economic costs of CVD seem to be largely of poor quality, studies have suggested that CVD costs around 2% of global GDP in direct costs, with indirect costs estimated to be more than double. Diabetes alone has been estimated to have a direct cost to countries in Latin America and the Caribbean of about $10 billion in the year 2000, with indirect costs estimated at over $50 billion. The impact on the developing world is particularly large as CVD strikes at an earlier age in these countries, occurring among adults of working age. Total annual direct costs for CVD in India have been modelled to account for $14.4 billion in 2016, with indirect costs estimated to bring the total amount to between $99.2 billion and $148.2 billion, amounting to between 4% and 6.5% of the country’s GDP.
What can be done to prevent cardiovascular disease?
CVD is highly preventable. Besides age, there is a number of lifestyle risks that contribute to the occurrence of CVD and are particularly prevalent in more developed countries. People in SAA have lower levels of a number of CVD risk factors compared to HICs, including tobacco use, cholesterol levels, and obesity. Similarly, South Asian countries have less obesity and East Asia/Pacific has less tobacco use, as well moderately less cholesterol and obesity. This illustrates that while the epidemiological transition is underway, the situation will likely worsen in the developing world in the coming decade. With the large number of intertwined risk factors that contribute to CVD, there is a number of possible avenues that prevention strategies could target.
There are four major environmental factors contributing to the development of CVD, namely air pollution, tobacco use, diet, and low physical activity. In 2019, CVD accounted for 51.5% and 30.5% of the total DALYs attributable to ambient and household air pollution, respectively. Exposure reduction in most of Southeast Asia has brought down the impact of household pollution drastically, however SAA has not felt the benefits of clean household energy sources so far. Increased attention to air pollution as a CVD risk factor is needed.
Increases in tobacco-attributable deaths and DALYs are due to population growth, especially in countries with a high number of tobacco users. Progress in reducing tobacco use has not yet been able to counter these demographic trends. Given that approximately 80% of current smokers live in LMICS, it is expected that population growth will continue to counter progress in tobacco control for the foreseeable future. While reduction of tobacco use has been a global health priority with the WHO establishing a Framework Convention on Tobacco Control, the adoption and enforcement of control measures has varied between countries.
Diet is a major contributor to the progression of CVD as it is implicated in the development of obesity, hypertension and other health conditions that are risk factors for CVD. Dietary risks include the sum of adverse effects of diets which includes underconsumption of some food types (e.g. fruits, vegetables, legumes, whole grains, nuts and seeds, milk, fiber, calcium, omega-3 fatty acids from seafood, and polyunsaturated fatty acids) and overconsumption of others (e.g. red meat, processed meat, sugar-sweetened beverages, trans-fatty acids, and sodium). Given the strong commercial interests that drive the sale of unhealthy food, progress towards improving diet quality is stalling. Policies limiting the consumption of added sugar, sodium, and harmful fats have largely been weakly implemented and their impact on global health has been limited. Exceptions to this are regulatory and fiscal interventions such as soda taxes and beverage reformulation programs that have led to lower intakes of added sugars. Similarly, there have been impactful programs that have removed trans-fats from the food supply, for example in the United States.
Lastly, low physical activity is an important risk factor for heart disease, stroke, diabetes, breast and colon cancers, as well as a number of other non-communicable diseases. Historically, health systems have neglected physical activity as a target for possible interventions, however, awareness is increasing as exemplified by the 2018 WHO Global Action Plan for Physical Activity. Promoting physical activity will necessitate collaboration between the health sector and other partners from transportation, education, urban planning, and workplaces.
There has been a number of studies looking into the cost-effectiveness of interventions relating to these risk factors and CVD more generally. Smoking cessation seems to be the most cost-effective prevention method for CVD. A 2007 study indicated that smoking cessation therapy is likely cost-saving due to reduced healthcare costs. Tobacco price increases through tax hikes have been estimated to cost between $3 and $42 per DALY averted, and a range of non-price interventions such as advertising bans, health warnings, and smoke-free laws would cost between $54 to $674 per DALY averted. Other modelling approaches have also determined that demand reduction strategies as proposed by the WHO’s Framework Convention for Tobacco Control belong amongst the most cost-effective prevention strategies.
The cost-effectiveness of salt reduction through public education has also been viewed as favorable, with cost estimates ranging from cost-saving to $250 per DALY averted depending on cost of intervention and assumptions regarding their effectiveness. Others have determined that centrally managed initiatives to control sodium intake seem to generally be cost-effective, but are underrepresented in Africa.
Reducing saturated fat intake and replacement of saturated fat with polyunsaturated fat has also been suggested to be cost-effective, with interventions estimated to be cost-saving or to cost less than $2900 per DALY averted, depending on the cost of media. Lastly, treatment of acute myocardial infarction with aspirin and atenolol has been demonstrated to be highly cost effective with treatment costing between $11 and $22 per DALY averted.
Who is already working on this?
Only 2% of global developmental health aid in LMICs goes towards cardiovascular health, with funding levels having stagnated since 2000. One of the large philanthropic players active in this field is Michael Bloomberg through Bloomberg Philanthropies. Just recently, Bloomberg Philanthropies contributed $115 million to Resolve to Save Lives’ work on cardiovascular disease over the next five years, in addition to the $100 million the organization in 2017. Other supporters include the Bill & Melinda Gates Foundation and the Chan Zuckerberg Initiative, which committed an additional $125 million to the initiative in 2017. Resolve to Save Lives is acting to limit salt intake, treat hypertension, and eliminate trans fats in the developing world. Besides this, Bloomberg’s public health program also includes a 16-year, $1.1 billion initiative to reduce tobacco use in LMICs, as well as programs in obesity prevention. In the field of tobacco control, the Bill & Melinda Gates Foundation has also been a prominent actor.
The World Heart Federation, which has more than 200 heart foundations as members, works in Africa to tackle the prevalence of hypertension by working with health workers. They also undertake global advocacy work promoting universal health coverage paid for by taxes on tobacco, alcohol and sugar-sweetened beverages. Other topics they advocate for is the fight against air pollution and tobacco.
Healthy Heart Africa (HHA) is a program launched by AstraZeneca in 2014, tackling hypertension and CVD, aiming to reach 10 million people with high blood pressure across Africa by 2025. HHA supports local health systems by increasing awareness of hypertension, training providers, and offering health education, screening, and reduced-cost treatment. Since first launching in Kenya in 2014, the program has expanded to seven more countries and has conducted over 25 million blood pressure screenings in community and healthcare facilities. Furthermore, Healthy Heart Africa has trained over 9100 healthcare workers. AstraZeneca also facilitates access to low cost, high-quality branded hypertensive medicines.
Prevention of CVD, amongst other non-communicable diseases, has also been a focus point of many governmental actors. In 2013, the WHO devised the 25x25 Global Action Plan, aiming to reduce premature deaths from non-communicable diseases by 25% by 2025. While HICs are likely able to meet these targets, low and middle-income countries are struggling due to insufficient funding, poor governance and a focus on curative services rather than prevention.
While there is a number of philanthropic, governmental and corporate funders in this space already, the fact that only a low percentage of global developmental health aid goes towards cardiovascular health, the extent of the problem with CVD being the number one cause of death globally, and the consistently rising case numbers, highlight that CVD prevention remains an underfunded field.
Where could additional funding go?
Advocacy
It seems that the most cost-effective interventions targeting CVD prevention rely on governmental action, such as tax increases, bans or other regulations concerning tobacco, fat and sugar. However, advocacy work often results in an all-or-nothing situation in which funds have either contributed to new regulations being passed or have had no impact whatsoever.
It is unclear to me whether Open Philanthropy would be able to provide meaningful support to advocacy work, given the need for not only money but also cooperation with local partners and connections to relevant governmental actors. In this case, access to money may not be a limiting factor and other large and well-connected funders such as the Bill & Melinda Gates Foundation, Bloomberg Philanthropies, as well as the WHO, may be better placed to fund and organize such efforts.
Scaling up and expanding existing programs
Besides policy advocacy, there is a number of community-targeting approaches that may provide cost-effective opportunities to tackle CVD prevention. One example would be behavior change campaigns tackling sodium consumption. The WHO has identified such campaigns as a ‘best-buy’ intervention and Resolve to Save Lives is one of the organizations undertaking this work.
Identifying and designing effective programs
As previously mentioned, tobacco control, even though a global health priority, has so far had limited success in the developing world. On the other hand, advocacy work championed by Resolve to Save Lives has proven very effective at removing trans-fats from the global food supply. Learning from effective advocacy work may hold valuable lessons for future campaigns. Furthermore, future campaigns should utilize the networks successful advocacy organizations have developed with key decision makers in countries around the world. Similarly, funders may work to identify and test effective community-based approaches that are scalable and impactful.
Open Questions/Limitations/Uncertainty
While CVD is undoubtably a major public health issue and a deserving area for funding, this short essay leaves a lot of open questions. My aim here was to provide an overview of the scale of the problem and the possibilities for prevention, but it will require more research to identify the best and most cost-effective interventions in this area.
Any measures of cost-effectiveness mentioned are derived from the literature and are therefore limited by the quality of the underlying research, which differs substantially across publications. Similarly, quantification of actual disease burden, as well as economic costs of CVD are limited by the underlying research methodology. As highlighted by vastly different estimates on the impact ischemic heart disease has in developing countries, global health studies of these nature are associated with a range of limitations which have to be acknowledged when organizations want to use the generated data to base policy decisions on.
There is a number of specific topics that I believe have a high potential for preventative interventions which I have not delved in further during this essay, but want to mention here:
- Promotion of physical activity targeting younger people (e.g. in school/education settings)
- Access to clean energy sources in SAA (to combat household air pollution)
- Treatment of acute myocardial infarction with aspirin and atenolol
References
