The global burden of kidney disease and the sustainable development goals

1The 17 sustainable development goals (SDGs) were adopted by the United Nations, as successors to the millennium development goals, with the broad goal of achieving healthy people living on a healthy planet. Although only SDG 3, that is, to ensure healthy lives and promote well-being for all at all ages, is specifically focused on health, achievement of all of the SDGs should have health benefits via impacts on the environment, governance and society.

2The Global action plan for the prevention and control of noncommunicable diseases 2013–2020 (hereafter called the 2013 action plan) outlined an approach to reduce the combined mortality from four major categories of noncommunicable disease, i.e. cancer, cardiovascular disease, chronic respiratory disease and diabetes, by 25% by 2025. Previously, these four categories had been prioritized in the 2008–2013 action plan because, collectively, they were believed to account for about 60% of global deaths and it was anticipated that a large proportion of these deaths could be prevented through elimination of shared risk factors, e.g. alcohol and tobacco use, poor diets and inadequate exercise. Although laudable, the 2013 action plan has been criticized for failing to acknowledge the broader drivers of the noncommunicable disease epidemics, other important noncommunicable diseases and the so-called causes of the causes of noncommunicable diseases and failing to place sufficient emphasis on the need for coordinated multisectoral action. We argue that kidney disease represents one of the important noncommunicable diseases missing from the 2013 action plan and that, given the many social and structural factors that directly affect risks and outcomes of kidney disease, multisectoral action to achieve the SDGs will help prevent and control such disease (Table 1).

3Although often considered a comorbidity of diabetes or hypertension, kidney disease has numerous complex causes. Importantly, such disease has an indirect impact on global morbidity and mortality by increasing the risks associated with at least five other major killers: cardiovascular diseases, diabetes, hypertension, infection with human immunodeficiency virus (HIV) and malaria. For example, the Global Burden of Disease (GBD) 2015 study estimated that 1.2 million deaths, 19 million disability-adjusted life-years (DALYs) and 18 million years of life lost from cardiovascular diseases were directly attributable to reduced glomerular filtration rates.,

4The GBD 2015 study also estimated that, in 2015, 1.2 million people died from kidney failure, an increase of 32% since 2005. In 2010, an estimated 2.3–7.1 million people with end-stage kidney disease died without access to chronic dialysis. Additionally, each year, around 1.7 million people are thought to die from acute kidney injury. Overall, therefore, an estimated 5–10 million people die annually from kidney disease. Given the limited epidemiological data, the common lack of awareness and the frequently poor access to laboratory services, such numbers probably underestimate the true burden posed by kidney disease. It is therefore possible that, each year, at least as many deaths are attributable to kidney disease as to cancer, diabetes or respiratory diseases, three of the four main categories targeted by the 2013 action plan.,, In addition, the estimated number of DALYS attributable to kidney disease globally increased from 19 million in 1990 to 33 million in 2013. In 2016, the DALYs associated with chronic kidney disease, along with those associated with cardiovascular disease, cancers, diabetes and neurological disorders, were found to have increased significantly between 1990 and 2015. A report from the GBD 2016 study highlighted the important omission of focus on chronic kidney disease and suggested that “the SDG agenda offers at best a minimal platform for drawing attention to the health care and monitoring needs of [chronic kidney disease].”

5Kidney disease is associated with a tremendous economic burden. High-income countries typically spend more than 2–3% of their annual health-care budget on the treatment of end-stage kidney disease, even though those receiving such treatment represent under 0.03% of the total population. In 2010, 2.62 million people received dialysis worldwide and the need for dialysis was projected to double by 2030. Globally, the total cost of the treatment of the milder forms of chronic kidney disease appears to be much greater than the total cost of treating end-stage kidney disease. In 2015, in the United States of America, for example, Medicare expenditures on chronic and end-stage kidney disease were more than 64 billion and 34 billion United States dollars, respectively. Much of the expenditure, morbidity and mortality previously attributed to diabetes and hypertension are attributable to kidney disease and its complications.,

6Worldwide, important risk factors for kidney disease include diarrhoeal diseases, HIV infection, low birth weight, malaria and preterm birth, all of which are also leading global causes of DALYs. Risks of kidney disease span the life-course and environmental, infection and lifestyle etiologies. If risk factors are identified early, acute kidney injury and chronic kidney disease can be prevented and, if kidney disease is diagnosed early, worsening of kidney function can be slowed or averted by inexpensive interventions, several of which are on the World Health Organization’s (WHO’s) so-called best buys list for noncommunicable disease management. Such interventions include counselling for cardiovascular disease, diabetes and hypertension, drug therapy, tobacco control, promotion of physical activity and the reduction of salt intake through legislation and food labelling. The timely identification and management of acute kidney injury and chronic kidney disease represent the most effective strategy to address the growing global burden sustainably., By advocating for a multisectoral approach, as a means to achieving the SDGs, it should be possible to reduce the incidence of kidney disease globally. We discuss the kidney-health-related opportunities offered by attempts to achieve each SDG (Table 1).

7In high-income countries, lower socioeconomic status is associated with greater risk of end-stage kidney disease because of behavioural and metabolic risk factors and reduced access to care. In low- and middle-income countries, the burden posed by such poverty-related kidney disease is even greater, because of associated infections, hazardous work, poor education and poor maternal health. In all countries, poverty is associated with lack of social protection and transportation, poor housing and unemployment. Lack of transportation restricts access to care even when treatment costs are not a major barrier. Poverty and lower socioeconomic status have been specifically identified as independent risks for both incident chronic kidney disease and the more rapid progression of such disease. In low-income countries where treatment costs have to be paid directly by patients, a month’s supply of essential medications for the treatment of chronic kidney disease can cost up to 18 days’ wages and the corresponding out-of-pocket costs of dialysis, for acute kidney injury or end-stage kidney disease, are much higher., In South Africa, where limited access to dialysis is government-funded, patients who are otherwise eligible for dialysis are frequently declined access because of their socioeconomic circumstances. For those who do access dialysis, the financial burden is exacerbated because they cannot be employed while receiving dialysis or travelling to and from the provider.

8Promotion of universal health coverage should reduce the financial hardship of patients with kidney disease and improve access to kidney care. The goal of eradicating poverty spans all of the other SDGs and is fundamental to improving kidney health. In turn, achievement of each SDG promises to promote equity and reduce poverty.

9Many low-income countries have problems with undernutrition and overnutrition, both are risk factors for kidney disease. Malnutrition predisposes young children to infections, e.g. diarrhoeal diseases and pneumonia, that are important risk factors for acute kidney injury. Among girls and female adolescents, undernutrition leads to underweight mothers and low-birth-weight offspring. Low birth weights, preterm births and pregnancies affected by diabetes and pre-eclampsia, which, combined, may represent up to 20% of pregnancies worldwide, are all associated with increased lifetime risk of chronic kidney disease in both mothers and children. Obesity increases the lifetime risk of end-stage kidney disease and maternal obesity is associated with adverse outcomes in pregnancy, including the gestational diabetes and preterm births that are associated with increased risk of chronic kidney disease.

10Adequate nutrition is a key tool for reducing the burden of chronic kidney disease. Groups with very low incomes often live in areas where access to healthful foods is very limited or non-existent. Some population-level strategies, e.g. public education about healthful food choices, regulation of the fat, salt and/or sugar contents of food and the regulation of programmes for the provision of public and/or school meals, can all improve kidney health. Reduction in dietary salt is proposed as a cost-saving best buy with great potential to avert deaths from kidney disease. Similarly, a tax on high-sugar beverages, as introduced in Mexico, where chronic kidney disease is the second leading cause of death, can lead to sustained decreases in the purchase of taxed drinks and may reduce diabetes-related kidney disease over time.

11SDG 3 has many links to better kidney health (Table 2 available at: http://www.who.int/bulletin/volumes/96/6/17-206441) including optimization of fetal development, prevention of infections, reduction of the mortality and morbidity of cardiovascular disease and mitigation of environmental exposures. The Global Kidney Health Atlas has provided an overview of the main gaps in kidney care globally: an absence of relevant policies, shortages of essential medications, reliable epidemiological data, relevant workforce capacity, infrastructure and research capacity and a persistent reliance on out-of-pocket payments. The Atlas emphasizes the need for a health-system-wide approach to kidney care and provides a baseline against which to measure progress. Work towards reducing the global burden of kidney disease will contribute to achieving SDG 3 (Table 2).

12Because they are, in general, responsible for most child care and housework, women in low- and middle-income countries may face greater challenges if they have chronic kidney disease – and other noncommunicable diseases, than men with similar health problems. Heavy demands on their time may explain why, even though chronic kidney disease is more common among women than men, fewer women than men receive dialysis. Child marriage and lack of access to family planning contribute to poor maternal health and increased risk of obstetrical complications, including acute kidney injury. Among urban adults in the United States, both gender and race appeared to affect glomerular filtration rates. Achievement of equity for women worldwide should reduce the burden of kidney disease.

13Globally, almost 800 million people lack access to safe water and 2.5 billion lack access to optimal sanitation. In low- and middle-income countries, waterborne and pestilent diseases associated with poor hygiene and sanitation are major causes of acute kidney injury and chronic kidney disease. Enteric diarrhoeal deaths, associated with lack of safe water, cause over 1 million deaths annually. Most of these deaths occur in children younger than five years and many can be attributed to dehydration-related acute kidney injury. Non-enteric diseases caused by waterborne pathogens, e.g. leptospirosis and schistosomiasis, are also major causes of kidney disease in low- and middle-income countries.

14Local availability of clean water would be expected to reduce the risk of diarrhoea-related acute kidney injury. Beyond infection-related kidney complications from contaminated water and poor sanitation, additional challenges exist. Water containing organic perfluoroalkyl acids and heavy metals has been associated with chronic kidney disease in several settings and pesticide-contaminated well water may contribute to the risk of some chronic kidney disease observed in Sri Lanka. Dehydration, in conjunction with heat stress, may have contributed to the epidemic of chronic kidney disease observed among young, economically productive male labourers in Central America and South-East Asia. The global burden of kidney disease should be reduced by ensuring the availability of clean water and adequate sanitation.

15Climate change, degradation of biodiversity, forest and land, and loss of marine resources, all likely increase the risk of kidney disease through multiple mechanisms, e.g. increases in food insecurity, the incidences of heat-related illness and infectious diseases and pollution. Deforestation and land degradation can bring humans into greater contact with vector-borne and waterborne pathogens, such as enteric bacteria and other pathogens that can directly cause kidney disease, e.g. those causing dengue fever, leishmaniasis, leptospirosis, malaria, schistosomiasis, trypanosomiasis and yellow fever.

16Reducing the global burden of kidney disease in turn will also be critical for mitigating some of the environmental impacts of dialysis. Each year, for example, the haemodialysis given to more than 2 million people requires 160 billion litres of water and generates over 900 000 tonnes of, predominantly plastic waste. Clean, local production of dialysis supplies, the reprocessing of dialysis filters, the reuse of dialysis water, solar-powered dialysis and waterless dialysis are all promising strategies that could creduce the environmental footprint of dialysis as well at its costs.

17Within low- and middle-income countries, access to dialysis is highly inequitable. Despite its relative cost–effectiveness, access to transplantation is even more inequitable because of cultural, financial and legislative barriers and infrastructural limitations. In the face of extreme social inequalities and a demand for transplants that markedly exceeds the supply, the trafficking of kidneys and other human organs remains a major concern.

18Disparities in the burden of kidney disease, which are particularly complex, arise from biological, environmental, genetic, lifestyle and sociocultural factors and need to be addressed via multilevel, systematic interventions. An example of the complexities involved has been described in the United States. There, in general, compared with other patients with similar disease, patients with chronic kidney disease from ethnic and racial minorities have delayed referral for care, lower incomes, report poorer physician–patient relationships and have less access to health care in general. The pervasive disparities in kidney disease will have to be addressed before SDGs 8, 10 and 17 can be achieved.

19Rapidly occurring urbanization has contributed to the rise of kidney disease and other noncommunicable diseases in low- and middle-income countries. In addition to the commonly associated lifestyle changes, e.g. a switch to high-calorie, sodium-rich diets and decreased physical activity, rapid urbanization has led to crowded cities with environmental pollution, a limited infrastructure and poor levels of sanitation and waste disposal. Such urbanization also means that more and more people are living in settings where a growing prevalence of noncommunicable diseases, e.g. diabetes, hypertension and obesity, is juxtaposed with environmental toxins and numerous infectious diseases. These changes portend a synergistic growth in the global burden of kidney disease. There may already be evidence of such growth in the ever-higher ranking of chronic kidney disease among leading cause of deaths, across all country income categories, between 1990 and 2016.

20By building resilient infrastructure while promoting sustainable industrialization, it should be possible to enhance health-care access while simultaneously reducing the risk of kidney disease. In low- and middle-income countries, urban planning, to improve hygiene and sanitation and reduce population densities and the transmission of the pathogens causing enteric infections, schistosomiasis and tuberculosis, should reduce the incidence of acute kidney injury and chronic kidney disease. At the same time, by promoting the development of parks, paths and efficient transport systems, urban planning could increase general levels of physical activity and so help reduce the risk of obesity-related kidney disease.

21The effective prevention of chronic kidney disease will require engagement with the corporate sector, whose interests may be in conflict with those of public health. Novel strategies are required to create incentives for the corporate sector to promote public health. Even under optimal circumstances, kidney disease cannot always be prevented and strategies to reduce the economic, physical and social burdens of end-stage kidney disease are needed. Innovative mechanisms to reduce dialysis costs and make dialysis less dependent on electricity and water could multiply opportunities for access to dialysis, especially in low- and middle-income countries. Innovation is also required to improve access to transplantation. Although opt-out or presumed-consent strategies have been proposed as a way of increasing the supply of organs from deceased donors, they remain contentious.

22Acute kidney injury after a road-traffic collision may result from rhabdomyolysis and multi-organ failure as well as blunt or penetrating kidney injury. Natural disasters are associated with increased rates of crush-injury-induced acute kidney injury and frequently lead to life-threatening interruptions of treatment among those with end-stage kidney disease. Similarly, forced migrants with chronic or end-stage kidney disease can face dangerous interruptions in their treatment or receive inadequate care, even in a high-income country such as the United States. Continued action on reducing the burden of road-traffic injuries and supporting efforts to integrate noncommunicable disease management into humanitarian relief efforts should help to reduce the burden of chronic and end-stage kidney disease.

23Exposure to armed conflict can result in acute kidney injury caused by crush injury and rhabdomyolysis and the severity of injuries sustained in combat strongly correlates with the subsequent risk of chronic kidney disease. Kidney disease is common in incarcerated populations and, in terms of their kidney health, prisoners may face a triple burden: of excess risk of kidney disease and its risk factors, of barriers to preventive care for established chronic kidney disease and of the suboptimal management of end-stage kidney disease. As an important step towards improving global health, much work is required globally to reduce conflict and disparities and enhance peace.

24The net health burden of kidney disease is substantial, growing and driven by complex interactions, between communicable and noncommunicable diseases, that are shaped by upstream environmental and socioeconomic disparities. Although kidney disease, whether acute, chronic or end-stage, can be extremely costly, it is also potentially preventable and adverse outcomes can often be delayed or prevented by inexpensive interventions. Kidney disease is highly prevalent, spans the life course and has substantial financial implications. Our response to such disease requires a systematic policy approach, to strengthen all relevant aspects of the health system and to facilitate integration of the promotion of kidney health within a comprehensive horizontal programme for the prevention and treatment of noncommunicable diseases (Table 2).

25Within each country, the local burden and prevalence of kidney disease and its risk factors and the local capacity to identify and manage such disease must be determined, as a prerequisite for fair priority setting and appropriate policy development. Diagnosis of kidney disease is often hampered by a lack of awareness among health-care workers and at-risk communities and by inadequate and often erratic access to laboratory testing. Broad policies are increasingly being adopted globally to curb dietary intakes of fat, salt and sugar. Such policies all promise to reduce the burden of chronic kidney disease. The burden of acute kidney injury could be reduced through the ongoing commitment to reduce the transmission of the pathogens causing infectious diseases.

26We need universal health coverage to tackle kidney disease successfully and ensure effective screening, prevention and early treatment. Effective and transparent policies to govern access to care for end-stage kidney disease should only be developed after there has been a thorough attempt to determine the local health priorities, especially in resource-poor settings. Engagement with all relevant stakeholders and innovative financing strategies will be required to maximize equitable access to care. The bidirectional and synergistic interplay between kidney disease and all of the SGDs must be acknowledged in the development of a multisectoral approach. Policies that foster domestic and international collaboration, improve occupational and road safety, limit organ trafficking, promote access to education and gender equality, reduce unemployment and tackle the predicted adverse effects of climate change may all reduce kidney disease and/or the disparities in the care for such disease. However, as noted by the United Nations Secretary-General in December 2017, in the control and prevention of noncommunicable diseases, “political commitments have not often been translated into concrete action.” On its own, policy-making is insufficient. Monitoring the impact of policies on kidney disease and the risk factors for such disease needs to be integrated into existing surveillance activities. Health workers and communities must be empowered to advocate for, and hold policy-makers accountable for, kidney health, as an important step towards achievement of the SDGs.