World Kidney Day 2008
Authors: Connie L. Davis, William E. Harmon, Jonathan Himmelfarb, Thomas Hostetter, Neil Powe, Paul Smedberg, Lynda A. Szczech, Peter S. Aronson
Journal: Journal of the American Society of Nephrology (2008)

Thursday, March 13, 2008 will mark the third iteration of World Kidney Day (WKD). The concept of an annual WKD was first proposed in 2003 and, through a joint collaboration between the International Federation of Kidney Foundations and the International Society of Nephrology, the first WKD was launched on March 7, 2006. The primary goal for WKD is to draw attention to a global pandemic of kidney disease, with its associated morbidity and mortality, primarily resulting from amplification of cardiovascular risk. The concept of WKD has caught on remarkably quickly, resonating throughout the kidney disease community worldwide, thereby providing an energizing focus for efforts to squarely place kidney disease into a global public health framework. This year, it is anticipated that kidney organizations in at least 60 countries will participate by organizing health screening events, public lectures, press conferences, political activities, and other efforts to better inform primary care physicians, allied health professionals, individuals and families with kidney disease, as well as government health officials about the burgeoning importance of kidney disease. The WKD concept stems directly from recent efforts to develop a simple, clinically relevant definition for chronic kidney disease (CKD). Before 2000, a consensus-driven, consistent definition of CKD did not exist.1 Since that time, national and international consensus groups have arrived at consensus definitions of CKD and issued clinical practice guidelines and position statements related to a standardized definition.2,3 The development of these standardized definitions for CKD helps reveal that kidney disease is not just a relatively infrequent but individually costly disease, particularly, end-stage renal disease (ESRD). But in truth, ESRD is a highly prevalent disease with high collective costs and important public health consequences. WKD emphasizes kidney disease as “common, harmful, and treatable” with a consequent impetus on kidney disease screening, detection, surveillance, prevention, and research.4,5 What should nephrologists be doing on WKD 2008? We think, as others have suggested,6–8 that this is an opportunity to simultaneously reflect on the past and look toward the future. The profession of nephrology is in the midst of a vital transformation, and the changing medical, social, public health, and political environments surrounding kidney disease will change the practice of nephrology.9 We think that, while reflecting on the many conundrums demanding attention concerning the epidemic of CKD, it is important for nephrologists to actively participate in the resultant medical, social, and political processes with a fundamental goal of improving outcomes for patients with kidney disease. Thus, WKD 2008 is a call to action for nephrologists in the United States and worldwide. THINKING GLOBALLY Beginning in 2005, the World Health Organization (WHO) has emphasized the importance of controlling chronic noncommunicable diseases as a neglected global health priority.10 The WHO estimates that chronic diseases were responsible for more than 60% (35 million) of all deaths in 2005, with more than 80% of these deaths occurring in low income and middle income countries. More recently, in a study of 23 selected low income and middle income countries, chronic diseases are responsible for 50% of the total disease burden in 2005.11 Lost economic productivity in these 23 countries from heart disease, stroke, and diabetes alone is estimated to be 84 billion U.S. dollars between 2006 and 2015. As a consequence, the WHO has targeted a 2% annual reduction in chronic disease death rates over the next 10 yr, which would avert 24 million deaths and save an estimated 8 billion dollars in these countries alone. The primary targets on a global level for intervention are the common causes of the major chronic diseases, which include unhealthy diet, excessive energy intake, physical inactivity, and tobacco use. Of note, these important modifiable risk factors have also been implicated in the development and progression of CKD. It is of interest to note that the WHO does not list CKD when evaluating the major chronic diseases from a global perspective.10 The WHO focuses on cardiovascular disease, cancer, chronic respiratory diseases, and diabetes as modifiable causes of projected global deaths from chronic disease. Nonetheless, CKD is a global health problem. In the United States, the prevalence of chronic CKD in adults may be as high as 13.1% of the population.12 Although detailed, population-based data from the rest of the world are less available, studies from Europe, Asia, and worldwide also support a high prevalence of CKD as well as CKD-associated cardiovascular morbidity and mortality.13–15 Furthermore, throughout the world, the prevalent use of renal replacement therapy and the cost of providing kidney transplantation and dialysis continue to escalate.16 The Kidney Disease Improving Global Outcomes, a not-for-profit foundation whose stated mission is to improve the care and outcomes of patients with kidney disease worldwide, recommends that the government should adopt a public health policy for CKD, an activity that can be catalyzed on WKD.17 THINKING NATIONALLY The most robust available epidemiologic data on the public health consequences of kidney disease emanates from the United States. Available data from the U.S. Renal Data System, and from nationally representative surveys, such as the National Health and Nutrition Examination Surveys, clearly establish the disease burden from CKD as a public health threat.18 In particular, CKD is highly prevalent, is associated with increased morbidity and mortality and healthcare costs, and disproportionately affects minorities and disadvantaged individuals. Furthermore, preventive strategies, including rigorous blood pressure control with the use of inhibitors of the renin-angiotensin system, can reduce the burden of kidney disease.19 Data are especially compelling with respect to subpopulations. A particular concern is the burden of CKD in the black population in the United States, where transition from moderate CKD to ESRD occurs at a threefold higher rate than is seen in white patients with CKD.20,21 Also of concern is the older-age population, where the prevalence of CKD is increased and who constitutes the fastest growing segment of the ESRD population.12,22 That there are health consequences to having CKD is nearly indisputable. As has recently been noted,23 CKD is associated with higher rates and faster progression of cardiovascular disease, stroke, overall mortality, and increased mortality, in the ICU setting, after coronary revascularization and after acute decompensated heart failure.24–27 Despite these robust epidemiologic data, there remain many gaps in our understanding of best clinical practice for patients with CKD, which can provide important research opportunities. Even from available epidemiologic data, it is not clear that individuals with diminished glomerular filtration rate (GFR) without the presence of hypertension or diabetes truly have a significantly increased cardiovascular risk, nor is it clear from interventional trial data that screening for low GFR or microalbuminuria will identify subjects who can undergo successful secondary cardiovascular risk reduction in the absence of other cardiovascular risk factors, such as diabetes mellitus and hypertension. It is also not clear how much of the diminished GFR found in the elderly is caused by parenchymal kidney disease as opposed to the natural effects of aging on kidney function. Finally, and perhaps most important, the evidence base from randomized clinical trials to support interventions in the CKD population has been woefully inadequate to date.23,28 Clinical studies evaluating novel therapeutic approaches to arresting the progression of kidney disease are desperately needed.29 Indeed, our therapeutic tools, although proven effective, remain limited in number. Thus, as has recently been noted,30 it is important for the public policy aspects of CKD not to get ahead of the available data, so as not to risk credibility for the nephrology profession. Further research is key. At the helm of kidney disease treatment is and must be the nephrologist, who must steer through a complex comprehensive treatment program. However, the nephrologist providing CKD care is acting in the context of many other changes in nephrology clinical practice. These changes include impending implementation of payment for quality programs, trends toward consolidation of the dialysis industry, and bundling of payment for dialysis services.9 Furthermore, although perhaps stabilizing, the incidence of ESRD increases faster than the prevalence of CKD.31 Application of our tools to treat CKD likely has contributed to the recent stabilization of the incidence of ESRD after decades of rapid growth, albeit at an unacceptably high number of 100,000 people per year. However, the arrival of the baby boom generation at the typical age for ESRD may reverse this trend unless strenuous efforts are applied. That there are too few nephrologists for the growing numbers of patients with ESRD has been well documented.32 New U.S. Renal Data System projections estimate more than 500,000 persons on dialysis by 2020 with an additional 250,000 living with a transplant.22 Although this issue has received attention, without action this will continue to become a greater problem in the upcoming decade with implications for both the quality and cost of care. ACTING LOCALLY People with CKD are largely unaware that they have reduced kidney function. Among those with an estimated GFR less than 30 ml/min per 1.73 m2, fewer than one half knew that they had kidney disease.12 The shockingly low proportions of people with kidney disease who are aware of their kidney disease (<20% in all strata of GFR)33 indicates that there is still major room for improvements in secondary prevention. Can we be so bold as to expect that a truly effective national program might result in a decrease in incident ESRD? Efforts to improve this situation are continuing, focusing largely on people at highest risk and their primary care providers. Nephrologists can play a major role, particularly by providing formal and informal public education to primary care colleagues (including general internist, family physicians, nurse practitioners, physician assistants, and diabetes educators). The American Society of Nephrology has developed a PowerPoint slide set that can be obtained at our website (http://www.asn-online.org). This set is useful for local presentations to general medical audiences such as Medical Grand Rounds, which may be the most important activity for nephrologists on WKD. Public education should continue to focus on fundamental concepts that are the cornerstone of the detection of kidney disease. As simple as the message sounds, the most important service that American Society of Nephrology members can provide is to advise primary care providers that two simple tests can detect almost all CKD. The estimated GFR and a urine albumin-to-creatinine ratio provide adequate testing.34 Nephrologists are best suited to helping the primary care provider determine who should be tested and how to interpret screening tests. It is already recommended that persons with diabetes be tested yearly for the presence of CKD.34 Testing hypertensives also seems cost-effective.35 Finally, because CKD is common among relatives of persons with ESRD and increases mortality in cardiovascular disease, many call for testing in these groups as well.36 Nephrologists are well positioned to encourage their local laboratories to provide estimated GFRs with serum creatinine. Material explaining the rationale and steps for the laboratory may be obtained at the National Kidney Disease Education Program web site (http://nkdep.nih.gov). Laboratory directors generally are very responsive to nephrologists' requests, and now nearly one half of clinical laboratories provide this service. Nephrologists should encourage all laboratories to do so. On WKD in 2008, each nephrologist should consider how he/she can contribute to an increase in the local screening, identification, and treatment efforts for kidney disease. Each nephrologist needs to help disseminate information on best practices for primary care providers in their referral base. As a profession, we need to work to evolve processes for efficient care patterns. This will not only improve our patients’ quality of lives but may also attract young physicians to the practice of nephrology. Nephrologists must also rededicate efforts and become increasingly involved, both locally and nationally, in advocacy for the importance of kidney disease, and in the redesign of kidney disease care models across the entire spectrum of disease severity. Finally, nephrologists across the country should be strong advocates for enhanced support from the National Institutes of Health for research on the causes and treatment of CKD. DISCLOSURES None.