About Kidney Disease
A diagnosis of kidney disease means that a person’s kidneys are damaged and cannot filter blood the way they should. This damage can cause wastes to build up in the body. Kidney disease can cause other health problems, such as heart disease. If you have kidney disease, it increases your chances of having a stroke or heart attack. Major risk factors for kidney disease include diabetes, high blood pressure, and family history of kidney failure.
Unless otherwise noted, data are from the United States Renal Data Service 2015 Annual Data Report.
Acute Kidney Injury (AKI): Sudden and temporary loss of kidney function.
Chronic Kidney Disease (CKD): Any condition that causes reduced kidney function over a period of time. Chronic kidney disease may develop over many years and lead to end-stage kidney (or renal) disease (ESRD).
The five stages of CKD are
- Stage 1: Kidney damage with normal kidney function (estimated GFR ≥90 mL/min per 1.73 m2) and persistent (≥3 months) proteinuria.
- Stage 2: Kidney damage with mild loss of kidney function (estimated GFR 60-89 mL/min per 1.73 m2) and persistent (≥3 months) proteinuria.
- Stage 3: Mild-to-severe loss of kidney function (estimated GFR 30-59 mL/min per 1.73 m2).
- Stage 4: Severe loss of kidney function (estimated GFR 15-29 mL/min per 1.73 m2).
- Stage 5: Kidney failure requiring dialysis or transplant for survival. Also known as ESRD (estimated GFR <15 mL/min per 1.73 m2).
Dialysis: Treatment to filter wastes and water from the blood. When their kidneys fail, people need dialysis to filter their blood artificially. The two main forms of dialysis are hemodialysis and peritoneal dialysis.
End-Stage Renal Disease (ESRD): Total and permanent kidney failure treated with a kidney transplant or dialysis.
Glomerular Filtration Rate (GFR): The rate at which the kidneys filter wastes and extra fluid from the blood; measured in milliliters per minute.
Proteinuria: Condition in which the urine has more-than-normal amounts of a protein called albumin.
- The overall prevalence of CKD in the general population is approximately 14 percent.
- High blood pressure and diabetes are the main causes of CKD. Almost half of individuals with CKD also have diabetes and/or self-reported cardiovascular disease (CVD).
- More than 661,000 Americans have kidney failure. Of these, 468,000 individuals are on dialysis, and roughly 193,000 live with a functioning kidney transplant.
- Kidney disease often has no symptoms in its early stages and can go undetected until it is very advanced. (For this reason, kidney disease is often referred to as a “silent disease.”)
- The adjusted incidence rate of ESRD in the United States rose sharply in the 1980s and 1990s, leveled off in the early 2000s, and has declined slightly since its peak in 2006.
- Compared to Caucasians, ESRD prevalence is about 3.7 times greater in African Americans, 1.4 times greater in Native Americans, and 1.5 times greater in Asian Americans.
- Each year, kidney disease kills more people than breast or prostate cancer. In 2013, more than 47,000 Americans died from kidney disease.1
- The overall prevalence of CKD increased from 12 percent to 14 percent between 1988 and 1994 and from 1999 to 2004 but has remained relatively stable since 2004. The largest increase occurred in people with Stage 3 CKD, from 4.5 percent to 6.0 percent, since 1988.
- Women (15.93 percent) are more likely to have stages 1 to 4 CKD than men (13.52 percent).2
Age-Adjusted Prevalence of CKD Stages 1-4 by Gender 1999-20122
- African Americans (17.01 percent) and Mexican Americans (15.29 percent) are more likely to have CKD than Caucasians (13.99 percent).3
Age-Adjusted Prevalence of CKD Stages 1-4 by Race/Ethnicity 1999-20123
- CKD often occurs in the context of multiple comorbidities and has been termed a “disease multiplier.” Almost half of individuals with CKD also have diabetes and self-reported CVD.
Distribution of NHANES participants with diabetes, self-reported cardiovascular disease, and single-sample markers of CKD, 2007-2012
- CKD often has no symptoms in its early stages and can go undetected until it is very advanced. (For this reason, kidney disease is often referred to as a “silent disease”).
NHANES participants with CKD aware of their kidney disease, 2001-2012
- Patient awareness is less than 10 percent for those with stages 1 to 3 CKD.
- Awareness is higher among people with Stage 4 CKD, who often experience obvious symptoms.
CVD and CKD
- People with CKD are at high risk for CVD, and the presence of CKD often complicates CVD treatment and prognosis.
- The prevalence of CVD is 69.6 percent among persons ages 66 and older who have CKD, compared to 34.7 percent among those who do not have CKD.
- Atherosclerotic heart disease is the most frequent CVD linked to CKD; its prevalence is more than 40 percent among people ages 66 and older.
- The percentage of people who undergo cardiovascular procedures is higher among those with CKD than among those without CKD.
Acute Kidney Injury (AKI)
- In 2013, the unadjusted rate of AKI hospitalizations in the Medicare population fell by 4.9 percent. This decrease was observed across all age and race groups.
- For Medicare patients ages 66 and older with an AKI hospitalization in 2011, the cumulative probability of a recurrent AKI hospitalization within 2 years was 48 percent.
- Among Medicare patients ages 66 and older with a first AKI hospitalization, the in-hospital mortality rate in 2013 was 9.5 percent (or 14.4 percent when including discharge to hospice), and less than half of all patients were discharged to their home.
Hospital discharge status of first AKI hospitalization for Medicare patients aged 66+, 2013
- After rising steadily from 1980 to 2001, the incidence rate of ESRD leveled off in the early 2000s and has declined slightly since 2006.
- The number of incident (newly reported) ESRD cases in 2013 was 117,162; the unadjusted incidence rate was 363 per million/year.
- Although the number of ESRD incident cases plateaued in 2010, the number of ESRD prevalent cases continues to rise by about 21,000 cases per year.
- African-Americans are about 3.5 times more likely to develop ESRD than Caucasians.
- Hispanics are about 1.5 times more likely to develop ESRD than non-Hispanics.
- In 2013, 88.2 percent of all incident cases began renal replacement therapy with hemodialysis, 9.0 percent started with peritoneal dialysis, and 2.6 percent received a preemptive kidney transplant.
- As of December 31, 2013, 63.7 percent of all prevalent ESRD cases were receiving hemodialysis therapy, 6.8 percent were being treated with peritoneal dialysis, and 29.2 percent had a functioning kidney transplant.
- The leading causes of ESRD in children during 2009-2013 were: cystic/hereditary/congenital disorders (33.0 percent), glomerular disease (24.6 percent), and secondary causes of glomerulonephritis (12.9. percent).
- A total of 1,462 children in the United States began ESRD care in 2013, and 9,921 children were treated for ESRD on December 31, 2013. The most common initial ESRD treatment modality among children overall was hemodialysis (56 percent).
- The number of children listed for incident and repeat kidney transplant was 1,277 in 2013.
- 17,600 kidney transplants were performed in the United States in 2013.
- Less than one-third of the transplanted kidneys were from living donors in 2013.
- From 2012 to 2013, there was a 3.1 percent increase in the cumulative number of recipients with a functioning kidney transplant.
- Among candidates newly wait-listed for either a first-time or repeat kidney-alone transplant in 2009, the median waiting time to transplant was 3.6 years.
- The number of deceased donors increased significantly since 2003, reaching 8,021 in 2013.
- The rate of deceased donors among African Americans more than doubled from 1999 to 2013.
- In 2012, the probability of 1-year graft survival was 92 percent and 97 percent for deceased and living donor kidney transplant recipients, respectively.
- The probability of patient survival within 1 year post-transplant was 95 percent and 98 percent in deceased and living donor kidney transplant recipients, respectively, in 2012.
- Since 1996, the probabilities of graft survival and patient survival have steadily improved among recipients of both living and deceased donor kidney transplants.
- A notable decrease in hospitalization rates occurred from 2012 to 2013. Rates decreased by 11 percent for CKD patients and by 10.1 percent for those without CKD. However, rates of both overall and cause-specific admissions increased with advancing stages of CKD.
- Hospitalizations increased among CKD patients with the presence of diabetes and CVD.
- Among hemodialysis patients, the overall number of hospitalizations for ESRD in 2013 was 1.7 admissions per patient year—down from 2.1 in 2005.
- Rates of readmission for CKD patients were higher than those for patients without CKD. In 2013, 22.3 percent of patients with CKD were readmitted to the hospital within 30 days, compared to only 15.8 percent of those without CKD.
Adjusted percentage of patients readmitted to the hospital within 30 days of discharge, among Medicare CKD patients aged 66+, discharged alive from an all-cause index hospitalization between January 1 and December 1, by year, 2001-2013
- In 2013, adjusted mortality rates remained higher for Medicare patients with CKD (117.9/1,000) than for those without CKD (47.5/1,000); and these rates increased with CKD severity, although this gap narrowed during the period 2001 to 2013.
- Male patients had slightly higher mortality rates (52.6/1,000) than females (43.4/1,000); this was more prevalent among those with CKD (males: 128.7/1,000; females: 110.0/1,000).
- Mortality rates continue to decrease for dialysis and transplant patients, having fallen by 28 percent and 40 percent, respectively, since 1996.
- CVD contributes to more than half of all deaths among patients with ESRD. Arrhythmias and cardiac arrest alone were responsible for more than one-third (37 percent) of CVD deaths.
Causes of death in ESRD patients, 2012-2014
- Overall, the rates of death among Medicare patients with CKD are declining; however, they are higher in patients with CKD than without CKD.
- The presence of diabetes and CVD along with CKD increases the risk of death.
All-cause mortality rates (per 1,000 patient years at risk) for Medicare patients aged 66+, by CKD status and year, 2001-2013 (adjusted)
Medicare Spending for CKD
- Medicare spending for patients with CKD ages 65 and older exceeded $50 billion in 2013 and represented 20 percent of all Medicare spending in this age group.
- More than 70 percent of Medicare spending for CKD patients ages 65 and older was incurred by those who also had diabetes, congestive heart failure, or both.
- Although spending was 12.7 percent higher for African Americans than Caucasians in 2013, this represented a reduction from the 19.6 percent gap that occurred in 2010.
- Spending was more than twice as high for patients with all three chronic conditions of CKD, diabetes, and congestive heart failure ($38,230) than in patients with only CKD ($15,614).
- Medicare fee-for-service spending for ESRD beneficiaries rose by 1.6 percent, from $30.4 billion in 2012 to $30.9 billion in 2013, accounting for 7.1 percent of the overall Medicare paid claims costs.
Statistics on Kidney Disease in the United States: U.S. Renal Data Service website, www.usrds.org.
Kidney Disease Health Topics from the National Institute of Diabetes and Digestive and Kidney Diseases: www.niddk.nih.gov/kidney-disease
This content is provided as a service of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the National Institutes of Health. The NIDDK translates and disseminates research findings through its clearinghouses and education programs to increase knowledge and understanding about health and disease among patients, health professionals, and the public. Content produced by the NIDDK is carefully reviewed by NIDDK scientists and other experts.
This information is not copyrighted. The NIDDK encourages people to share this content freely.