Kidney Diseases

An illustration of where kidneys are within the body

Chronic Kidney Disease (CKD) is a condition in which the kidneys are damaged and cannot filter blood as well as they should; excess fluid and wastes from the blood remain in the body and may cause other health problems, such as heart disease, anemia, stroke, and bone disease. Kidney disease often can worsen over time and may lead to kidney failure, which requires dialysis or a kidney transplant. An estimated 37 million American adults have CKD, and kidney diseases are the ninth leading cause of death in the United States. CKD has two main causes: high blood pressure and diabetes. NIDDK-supported research has led to critical knowledge that has improved the health and quality of life of people with CKD. Acute kidney injury (AKI) is a common complication of hospitalization, with a variety of causes that preferentially affects the elderly and African Americans.

Yesterday

  • About one-third of patients with type 1 diabetes and one-sixth of patients with type 2 diabetes were destined to develop kidney failure.
  • Two lifesaving renal replacement therapies, dialysis and renal transplantation, developed through fundamental NIH research in the 1960s, were increasingly available; however, neither was ideal.
  • Dialysis left patients feeling exhausted and unable to work. Patients suffered from disabling bone disease, dementia caused by aluminum intoxication, and severe fatigue from uncontrollable anemia. High cardiovascular disease death rates limited life expectancy. Anemia was a common clinical problem for dialysis patients, which affected health and quality of life. Treatments such as transfusions and anabolic steroids had many complications.
  • Some patients were lucky enough to get a kidney transplant, which greatly improved their quality of life and life expectancy. However, transplantation was not common, and acute rejection resulted in transplantation failure rates of 30 to 50 percent. Infections due to immunosuppression in kidney transplant patients were common and life-threatening.
  • Screening methods for kidney disease were not very sensitive, so it was difficult to identify early stages of diabetic kidney disease.
  • Few treatments for kidney disease were available, and the importance of controlling blood sugar and blood pressure was not recognized. Kidney failure was increasing at epidemic rates.
  • There was no effective treatment for acute kidney injury (AKI); death rates for hospitalized patients with AKI were over 50 percent. AKI and CKD were considered separate syndromes.
  • Through the 1980s and 1990s, the number of patients developing end-stage kidney failure nearly doubled each decade.

Today

  • In 2017, over 746,000 patients received treatment for ESRD: over 523,000 received either hemodialysis or peritoneal dialysis, and close to 223,000 were living with a kidney transplant. In 2017, treating Medicare beneficiaries with CKD cost over $84 billion, and treating people with end-stage renal disease cost an additional $36 billion.
  • Management of complications has markedly improved the quality of life of dialysis patients. The development of erythropoietin, supported in part by the NIH, has revolutionized the treatment of anemia and improved the quality of life of countless end-stage kidney disease patients. As a result of improved treatment, the number of new dialysis patients has stabilized. However, premature death due to cardiovascular disease and all other causes are higher in adults with chronic kidney disease. High cardiovascular death rates in dialysis patients are also a serious problem.
  • Kidney disease can be detected earlier by standardized blood tests to estimate renal function and monitoring of urine protein excretion.
  • Kidney transplantation is widely available, although limited organ availability has resulted in longer waiting times. Transplant failure due to acute rejection is much less common.
  • New drugs, such as Angiotensin-converting enzyme (ACE) inhibitors and Angiotensin II receptor blockers (ARBs), better control blood pressure, improve cardiovascular outcomes and slow the rate of kidney damage.
  • NIDDK research has shown many cases of AKI culminate in the development of CKD. Treatment to improve outcomes of AKI may decrease the incidence and severity of CKD.
  • Foundational research, supported in part by NIDDK, has led to the discovery that drugs inhibiting a protein called SGLT can slow the progression of kidney disease in people with type 2 diabetes.
  • Because kidney disease often runs in families, the NIH has carried out several genetic studies of kidney disease. Researchers are learning how to identify genetic markers that might predict who will get kidney damage, especially in African Americans. Variants in the APOL1 gene have been shown to account for much of the 2- to 4-fold increase in kidney failure in African Americans compared to whites. To build on this knowledge, the NIDDK, NIMHD, and NIAID launched the APOL1 Long-term Kidney Transplantation Outcomes Network (APOLLO) study, which is comprehensively assessing the effects of APOL1 variants on the risk of kidney transplant failure across all the transplant centers in the U.S. APOLLO is also studying the impact of APOL1 variants on the health of living kidney donors.

Tomorrow

  • The continued development and testing of new detection strategies, therapies, and community education is expected to result in fewer people developing advanced chronic kidney disease and kidney failure, requiring less need for dialysis and transplantation. NIDDK is conducting research in a range of scientific areas that will help us realize these benefits for patients.
  • The best hope for reducing the human and economic costs of chronic kidney disease and end-stage renal disease in the future lies in prevention. NIDDK supports information and education programs designed to bridge the gap between scientific evidence and clinical practice by focusing on the minority communities at highest risk of kidney disease and the healthcare professionals who serve these patients.
  • NIDDK-supported research efforts to identify new intervention strategies and mechanisms that drive susceptibility to future CKD may lead to improved clinical outcomes and quality of life in patients surviving an episode of AKI.
  • An important goal for the future of nephrology is personalized medicine: delivering the right treatment for the right patient at the right time. Toward that goal, the NIDDK-supported Kidney Precision Medicine Project (KPMP) will ethically and safely obtain kidney biopsies from a range of people with common kidney diseases and analyze the tissue to redefine new molecular subgroups to replace more traditional diagnostic and pathologic categories. Cutting-edge technologies will identify critical cells, pathways, and molecular targets for the development of new therapies. KPMP will generate a revolutionary set of 2- and 3-D kidney maps that could pave the way for novel, personalized treatments.
  • NIDDK is supporting the Re(Building) a Kidney Consortium to slow or reverse kidney function decline, with the goal of preventing irreversible, debilitating kidney failure. This consortium is developing revolutionary approaches that may restore lost kidney function by creating implantable engineered tissue structures that replicate kidney function or by directly regenerating tissue in a damaged kidney. This research could lead to paradigm-shifting treatment approaches for people with CKD.