U.S. Kidney Failure Rates Stabilize, Ending
a 20-Year Climb
Troubling Racial Disparities Persist
After 20 years of annual increases from 5 to 10 percent, rates
for new cases of kidney failure have stabilized, according to new
research from the National Institute of Diabetes and Digestive
and Kidney Diseases (NIDDK) of the National Institutes of Health.
At the same time, dramatic racial disparities persist.
In 2003, the rate for new cases of kidney failure was 338 per
million population, down slightly from 2002 and continuing a four-year
trend, finally allowing researchers to be cautiously optimistic
that rate decreases have not happened by chance. The average annual
increase has been less than 1 percent since 1999, compared to an
average 5 percent in the previous decade, according to research
published recently by NIDDK’s U.S. Renal Data System (USRDS) at www.usrds.org and
being presented next month at the annual scientific meeting of
the American Society of Nephrology.
Diabetes and high blood pressure remain the leading causes of
kidney failure, accounting for 44 percent and 28 percent of all
new cases, respectively. The most striking trends were found in
diabetes, where rates for new cases in whites under age 40 were
the lowest since the late 1980’s, in stark contrast to rates for
their African American counterparts, which have not budged.
“It’s gratifying to see progress, however small, and to know that
NIDDK activities undoubtedly have had a hand in that success,” said
Paul W. Eggers Ph.D., NIDDK’s co-director for the USRDS. “But persistent
disparities are sobering.”
Credit for recent gains likely goes to clinical strategies proven
in the 1990s to significantly delay or prevent kidney failure:
angiotensin-converting enzyme inhibitors (ACE-inhibitors) and angiotensin
receptor blockers (ARBs), which lower protein in the urine and
are thought to directly prevent injury to the kidneys' blood vessels;
and careful control of diabetes and blood pressure. The launch
of private and government programs to improve care and increase
awareness coincided with these developments, including NIDDK’s
National Kidney Disease Education Program (NKDEP).
NKDEP encourages early diagnosis and management by increasing
awareness about:
- the connection between diabetes, high blood pressure and kidney
disease
- strategies proven to prevent or delay kidney failure
- estimating kidney function (eGFR) to find kidney disease earlier
- efforts to standardize testing for kidney disease and encourage
more labs to automatically report eGFR, and
- time-saving tools for health professionals at www.nkdep.nih.gov,
including eGFR calculators that eliminate most of the work to
estimate kidney function; and a letter template, which automatically
calculates patient-specific eGFR, generates a list of next steps
based on kidney disease stage and is designed to improve communication
between kidney specialists and primary care physicians.
Despite incremental successes in preventing kidney failure and
in improving health and survival of people who have it already,
the increasing and aging U.S. population means that more people
than ever before are getting and living with the disease. In 2003,
nearly 537,000 people received dialysis or a kidney transplant.
The cost to Medicare was $18.1 billion, with another $9.2 billion
borne by private insurers and patients. Another 10 million people
in the United States have earlier kidney disease; most don’t know
they have it, let alone that the disease increases the risk for
premature death, heart attacks, strokes, and other problems.
The research also found both encouraging and discouraging news
about the quality of care for people with chronic kidney disease
(CKD), an earlier stage that precedes kidney failure. Tests to
find kidney disease at the earliest, most-treatable stages are
not widely used. Only 10 percent of the general Medicare population
had a blood test and only 5 percent had urine tested for kidney
disease. But, while ACE-inhibitors and ARBs are still underutilized,
there has been a dramatic increase in their use. In the past decade,
the use of these drugs doubled among people over age 60 with CKD,
from 16 percent to 32 percent of patients, and nearly half of those
who also had diabetes or hypertension or congestive heart failure
used them.
“We could prevent or delay a lot more kidney failure, simply by
using the box of tools that are already in the trunk,” said Josephine
P. Briggs, M.D., a kidney specialist and director of NIDDK’s Division
of Kidney, Urologic, and Hematologic Diseases.
USRDS research depends on collaborations with other agencies
of the U.S. Department of Health and Human Services (HHS), especially
the Centers for Medicare and Medicaid Services, but also the
United Network for Organ Sharing and the Centers for Disease
Control and Prevention. Patient registries for other countries
also contribute data for analyses.
NIDDK, part of the National Institutes of Health (NIH), conducts
and supports research and education programs on kidney disease
and diabetes, among others. Learn more about NIDDK programs and
diseases at www.niddk.nih.gov.
The National Institutes of Health (NIH) — The Nation's
Medical Research Agency — includes 27 Institutes and
Centers and is a component of the U. S. Department of Health
and Human Services. It is the primary Federal agency for conducting
and supporting basic, clinical, and translational medical research,
and it investigates the causes, treatments, and cures for both
common and rare diseases. For more information about NIH and
its programs, visit http://www.nih.gov. |