The kidneys are the body’s filtration system that removes waste and extra fluid from the blood. Further, the kidneys maintain electrolyte stability, help to control blood pressure, and produce hormones to keep the body and blood healthy. Kidney disease occurs when the kidneys become damaged and can no longer filter blood like they should, often due to diabetes or high blood pressure—the most common causes of kidney disease. For most people, kidney disease unfolds slowly over many years and often has no signs or symptoms until the disease is very advanced, such that less than 15 percent of people in the late stages of kidney disease are aware of their disease. However, early detection is possible through blood and urine tests, which can delay or prevent the progression of kidney disease. Treatment may include, for example, taking medicines to manage high blood pressure to protect the kidneys. However, even with treatment, kidney disease usually cannot be cured. Instead, it may get worse over time leading to kidney failure, or ESRD, which may lead to death without dialysis treatment or a kidney transplant. While anyone can develop kidney disease, regardless of age or race, African Americans, Hispanics, and Native Americans are at high risk for ESRD, due, in part, to high rates of diabetes and high blood pressure in these communities. Medicare provides health coverage for most individuals with ESRD, regardless of their age. Medicare spending on treatment for individuals with ESRD has almost doubled in recent years— from $16.2 billion in 2003 to $30.9 billion in 2013—as the number of Medicare beneficiaries with this condition and annual Medicare spending per person have increased. NIH—which had a total budget of $30 billion in fiscal year 2015—is comprised of the Office of the Director, and 27 institutes and centers (IC) that focus on specific diseases, particular organs, or stages in life, such as childhood or old age. Twenty-four of the 27 ICs receive specific appropriations to support, plan, and manage their research programs. Within NIDDK, the Division of Kidney, Urologic, and Hematologic Diseases researches diseases of the kidney and also focuses on the fields of urology and hematology. Specifically, the division’s areas of kidney research include chronic kidney disease, ESRD, cystic kidney disease, acute kidney injury, and kidney donation. NIDDK’s budget in fiscal year 2015 was $1.75 billion, of which $430 million (25 percent) was allocated to the division. NIDDK and the other ICs accomplish their missions primarily through extramural research conducted by scientists and research personnel working at universities, medical schools, and other research institutions. Most extramural research funding is provided for investigator-initiated research projects for which researchers submit applications in response to broad funding opportunity announcements that span the breadth of NIH’s mission. In addition to the broad investigator research announcements, ICs issue more narrowly scoped solicitations for research targeting specific areas. All extramural research project applications follow NIH’s process of peer review, which was established by law, and includes two sequential levels of review. The first level involves panels of non-governmental experts to assess the scientific merit of the proposed science, and the second level involves panels of non-governmental experts and leaders of non-science fields, including patient advocates, that, in addition to scientific merit, consider the IC’s mission and strategic plan goals, public health needs, scientific opportunities, and the balance of the IC’s research across its various divisions and centers. In January 2007, Congress directed NIH to establish an electronic system to categorize the research grants and activities of the Office of the Director and the ICs. In response, NIH implemented RCDC in February 2008, which reports on the amount of NIH funding in a given fiscal year associated with one or more categories of diseases, conditions, or research areas. RCDC reports publicly on 265 of these categories. To assign an NIH project to the appropriate categories, RCDC uses a computer-based text-mining tool that recognizes words and phrases in project descriptions. Projects may fall into one or more RCDC categories. For example, a study on how diabetes leads to kidney disease would be listed in the “diabetes” and “kidney disease” categories. The system includes reporting tools that can be used to generate publically available, web-based reports on total funding amounts for the research projects related to each RCDC category. NIH funding for biomedical research related to kidney disease totaled approximately $564 million for 1,493 projects in fiscal year 2015—an increase of 2.7 percent from fiscal year 2014. NIDDK provided the majority (60 percent) of this funding; other ICs provided the remaining 40 percent of funding. In NIDDK, the average research project award was about $345,000, and ranged from approximately $27,120 for the smallest to $28.5 million for the largest. (See fig. 1.) The kidney disease projects funded by each IC reflect their different missions. As the lead NIH institute for kidney disease, NIDDK funds a broad kidney disease research portfolio, while the other ICs fund kidney disease research in more specific areas that relate to their missions. For example, one component of the National Heart, Lung, and Blood Institute’s mission is heart health, and as noted earlier, heart disease can be a cause of kidney disease. Therefore, that institute funds research that examines how kidney disease impacts cardiovascular health. Similarly, the National Institute of Allergy and Infectious Diseases fulfills its mission—to study immunology and infectious diseases—through kidney disease research that primarily addresses how a patient’s immune system responds to a kidney transplant, as well as the negative impacts of chronic-autoimmune diseases on long-term kidney health. Although NIH is the primary federal agency involved in biomedical research on kidney disease, there are other federal agencies that conduct and fund research in this area. Appendix II describes these agencies’ kidney disease research efforts. To provide context for the level of NIH research funding for kidney disease, we also analyzed NIH funding levels for other leading diseases and conditions in the United States—those that had high mortality, were among the most prevalent chronic conditions, or both. The RCDC categories corresponding to these leading diseases and conditions, which are shown in table 1, are neither mutually exclusive nor exhaustive. Categories do not exist for all diseases and conditions, and NIH officials said that a project may be included in, on average, six RCDC categories. For example, a $1 million project on “depression in older men with diabetes” could be placed into each of four categories: (1) depression ($1 million), (2) aging ($1 million), (3) mental health ($1 million), and (4) diabetes ($1 million). Therefore, while RCDC produces a complete list of the funded projects included within a category, it is not designed to produce non-overlapping assignment of projects or fractions of projects to categories. In fiscal year 2015, NIH research funding varied across the categories corresponding to the diseases and conditions in our analysis, from $8 million for fibromyalgia to nearly $5.4 billion for cancer. (See table 1.) The variation in research funding across the RCDC categories in table 1 reflects a range of factors, including differences in each IC’s mission, congressional appropriations, and research priorities. An IC’s appropriation sets the amount of funding available for the given fiscal year. Furthermore, appropriations may include mandated spending for a specific disease, as is the case, for example, for type I diabetes. Research priorities can affect the amount of funding devoted to the study of a particular disease. We previously reported that ICs considered a variety of factors when setting research priorities and NIH officials confirmed that this is still the case. The factors ICs consider when setting research priorities include scientific needs and opportunities—identifying those research areas that have advanced such that additional research funding could yield a breakthrough; gaps in funded research and investment, such as diseases that may attract limited private sector research funding; burden of disease—the impact of a health problem—on a population, as measured by indicators such as prevalence, mortality, and impact on quality of life; and public health needs, such as an emerging public health threat that needs to be addressed, like the Zika virus. NIDDK works with the broader kidney care community to develop its kidney disease research priorities by using a web-based forum, hosting a variety of meetings for kidney disease stakeholders, and by assessing its research portfolio. NIDDK considers the community’s input in the context of the institute’s ongoing work and its knowledge of the current state of kidney disease research to develop funding announcements that target high-priority research areas that are not being adequately addressed. According to NIDDK officials, NIDDK’s process for obtaining input from the kidney care and scientific communities, and developing research priorities is iterative by design to help ensure that the institute’s priorities evolve to reflect the latest research developments and needs of the communities. (See fig. 2.) NIDDK established and maintains the Kidney Research National Dialogue (KRND)—an open, interactive, web-based forum—to obtain input from the kidney care research community. The KRND began in 2010 by allowing participants to submit, comment on, and prioritize potential kidney disease research objectives for the kidney care and research community and to be supported by NIDDK through workshops and initiatives. (See app. III for more information on the KRND.) With the help of established researchers in the kidney disease field, NIDDK staff reviewed and distilled the KRND submissions into kidney disease research priorities that address a variety of topic areas such as improving therapies for chronic kidney disease, promoting human studies to better understand kidney function, and advancing dialysis technology and research.