(Press-News.org) A new, international study from the Chronic Kidney Disease Prognosis Consortium found that use of blood levels of cystatin C to estimate kidney function—alone or in combination with creatinine—strengthens the association between kidney function and risks of death and end-stage renal disease.
The findings, reported in the September 5 edition of the New England Journal of Medicine, suggest that the use of cystatin C as a measurement of kidney function could lead to better staging and risk classification of chronic kidney disease. They also suggest that the measurement potentially could allow for more targeted management of the condition, allow for better and safer prescribing of medications, and more judicious use of procedures that may harm the kidney.
Kidney function estimates are central to the diagnosis and management of chronic kidney disease, and these estimates are usually based on the creatinine blood test. However, the creatinine test can miss early losses of kidney function, particularly in patients with low muscle mass.
Cystatin C, a newer kidney function marker, is becoming more widely available and in some settings provides improved estimates of kidney function.
For the study, the researchers performed a meta-analysis of 11 general-population studies (with 90,750 participants from the United States, Europe and Australia) and five studies of participants with chronic kidney disease (2,960 participants) for whom standardized measurements of serum creatinine and cystatin C were available. They compared the association of kidney function, as calculated by the measurement of creatinine, cystatin C, or the combination of creatinine and cystatin C, with the rates of death, death from cardiovascular causes, and end-stage kidney disease, and they compared kidney disease stages that were classified alternatively by creatinine or cystatin C.
Results of the analyses using cystatin C demonstrated that the risks associated with declining kidney function emerge when kidney function reaches approximately 85 ml per minute per 1.73 m2, much earlier than the threshold of chronic kidney disease (i.e., 60 ml/min/1.73m2). In contrast, with creatinine based kidney function estimates, these risks of kidney function cannot be observed until kidney function is below 60 ml/min/1.73m2 by which time chronic kidney disease has already developed. The kidney function stages categorized by cystatin C were much better at reflecting future risk than were the stages based upon creatinine estimates of kidney function.
“Clearly cystatin C defines an important preclinical period of reduced kidney function before chronic kidney disease can be diagnosed with creatinine alone, and this period may last one to two decades,” said Michael Shlipak, MD, MPH, lead author of the article and chief of general internal medicine at the San Francisco VA Medical Center. Shlipak also is a professor of medicine, epidemiology and biostatistics at UCSF. “Cystatin C allows patients’ kidney function to be categorized more accurately; the use of cystatin C in clinical medicine could help us to be more precise in the diagnosis of chronic kidney disease, and in the future to target high-risk patients for treatment in order to prevent chronic kidney disease.”
Chronic kidney disease affects over 10 percent of adults worldwide. The researchers note that, unlike creatinine, cystatin C is not affected by muscle mass, so it requires less adjustment for factors like age and gender. In addition, cystatin C works similarly as a marker of kidney function in blacks and whites.
“Accurate detection and staging of chronic kidney disease are integral components of clinical medicine, since such evaluations have a major effect on disease labeling, interventions, drug doses, and risk stratification for clinical procedures,” said Josef Coresh, MD, PhD, the Consortium’s principal investigator and professor in the Johns Hopkins Bloomberg School’s Department of Epidemiology. “Our study provides definitive evidence that the measurement of cystatin C improves risk categorization based on estimated kidney function, as judged by the risk of death from any cause and to a lesser extent the risks of death from cardiovascular causes and end-stage kidney disease.”
“Cystatin C versus Creatinine in Determining Risk Based on Kidney Function” was written by the CKD Prognosis Consortium, which includes approximately 200 collaborators and data from 40 countries.
INFORMATION:
Funding sources include the National Kidney Foundation for the CKD Prognosis Consortium and a variety of sources such as the National Institutes of Health, the Medical Research Councils, foundations, and industry sponsors for collaborating authors and cohorts.
About UC San Francisco (UCSF)
UCSF is a leading university dedicated to promoting health worldwide through advanced biomedical research, graduate-level education in the life sciences and health professions, and excellence in patient care. It includes top-ranked graduate schools of dentistry, medicine, nursing and pharmacy; a graduate division with top-ranked programs in basic biomedical, translational, social and population sciences; as well as a preeminent biomedical research enterprise and two top-ranked hospitals, UCSF Medical Center and UCSF Benioff Children’s Hospital.
About Johns Hopkins Bloomberg School of Public Health
As a leading international authority on public health, the Johns Hopkins Bloomberg School of Public Health is dedicated to protecting health and saving lives. Every day, the Bloomberg School works to keep millions safe from illness and injury by pioneering new research, deploying its knowledge and expertise in the field, and educating tomorrow's scientists and practitioners in the global defense of human life. Founded in 1916 as part of the Johns Hopkins University, the Bloomberg School of Public Health is the world’s oldest and largest independent school of public health. More information: http://www.jhsph.edu.
Follow UCSF
UCSF.edu | Facebook.com/ucsf | Twitter.com/ucsf | YouTube.com/ucsf
Relationship of kidney function estimates to risk improves by measuring cystatin C in the blood
2013-09-05
ELSE PRESS RELEASES FROM THIS DATE:
Experimental compound reverses Down syndrome-like learning deficits in mice
2013-09-05
Researchers at Johns Hopkins and the National Institutes of Health have identified a compound that dramatically bolsters learning and memory when given to mice with a Down syndrome-like condition on the day of birth. As they report in the Sept. 4 issue of Science Translational Medicine, the single-dose treatment appears to enable the cerebellum of the rodents' brains to grow to a normal size.
The scientists caution that use of the compound, a small molecule known as a sonic hedgehog pathway agonist, has not been proven safe to try in people with Down syndrome, but say ...
New laser-based tool could dramatically improve the accuracy of brain tumor surgery
2013-09-05
ANN ARBOR, Mich. — A new laser-based technology may make brain tumor surgery much more accurate, allowing surgeons to tell cancer tissue from normal brain at the microscopic level while they are operating, and avoid leaving behind cells that could spawn a new tumor.
In a new paper, featured on the cover of the journal Science Translational Medicine, a team of University of Michigan Medical School and Harvard University researchers describes how the technique allows them to "see" the tiniest areas of tumor cells in brain tissue.
They used this technique to distinguish ...
Training the older brain in 3-D: Video game enhances cognitive control
2013-09-05
Scientists at UC San Francisco are reporting that they have found a way to reverse some of the negative effects of aging on the brain, using a video game designed to improve cognitive control.
The findings, published this week in Nature, show how a specially designed 3-D video game can improve cognitive performance in healthy older adults. The researchers said it provides a measure of scientific support to the burgeoning field of brain fitness, which has been criticized for lacking evidence that such training can induce lasting and meaningful changes.
In the ...
Back of pack health warnings make little impact on teen smokers
2013-09-05
Back of pack picture or text warnings depicting the dangers of smoking, make little impact on teen smokers, particularly those who smoke regularly, suggests research published online in Tobacco Control.
Pictorial warnings work better than text alone, but if positioned on the back of the pack are less visible and less effective, say the researchers.
In 2008 the UK became the third European Union country to require pictorial health warnings to be carried on the back of cigarette packs.
In only five out of the 60 countries worldwide that have introduced this policy do ...
Chlamydia and gonorrhoea infections linked to pregnancy complications
2013-09-05
Becoming infected with chlamydia or gonorrhoea in the lead-up to, or during, pregnancy, increases the risk of complications, such as stillbirth or unplanned premature birth, indicates research published online in the journal Sexually Transmitted Infections.
The researchers analysed the birth records of more than 350,000 women who had had their first baby between 1999 and 2008 in New South Wales, Australia's most heavily populated state.
The researchers wanted to find out if infection with either chlamydia or gonorrhoea in the lead-up to, or during, pregnancy, had any ...
Queen Mary scientists uncover genetic similarities between bats and dolphins
2013-09-05
The evolution of similar traits in different species, a process known as convergent evolution, is widespread not only at the physical level, but also at the genetic level, according to new research led by scientists at Queen Mary University of London and published in Nature this week.
The scientists investigated the genomic basis for echolocation, one of the most well-known examples of convergent evolution to examine the frequency of the process at a genomic level.
Echolocation is a complex physical trait that involves the production, reception and auditory processing ...
Pacific flights create most amount of ozone
2013-09-05
The amount of ozone created from aircraft pollution is highest from flights leaving and entering Australia and New Zealand, a new study has shown.
The findings, which have been published today, Thursday 5 September, in IOP Publishing's journal Environmental Research Letters, could have wide-reaching implications for aviation policy as ozone is a potent greenhouse gas with comparable short-term effects to those of carbon dioxide (CO2).
The researchers, from Massachusetts Institute of Technology, used a global chemistry-transport model to investigate which parts of the ...
Clinical tool accurately classifies benign and malignant spots on lung scans of smokers
2013-09-05
This news release is available in French.
Vancouver, BC – A Terry Fox Research Institute(TFRI)-led study has developed a new clinical risk calculator software that accurately classifies, nine out of ten times, which spots or lesions (nodules) are benign and malignant on an initial lung computed tomography (CT) scan among individuals at high risk for lung cancer.
The findings are expected to have immediate clinical impact worldwide among health professionals who currently diagnose and treat individuals at risk for or who are diagnosed with lung cancer, and provide ...
Heart attack death rates unchanged in spite of faster care at hospitals
2013-09-05
ANN ARBOR, Mich. -- Heart attack deaths have remained the same, even as hospital teams have gotten faster at treating heart attack patients with emergency angioplasty, according to a study in this week's New England Journal of Medicine.
Hospitals across the country have successfully raced to reduce so-called door-to-balloon time, the time it takes patients arriving at hospitals suffering from a heart attack to be treated with angioplasty, to 90 minutes or less in the belief that it would save heart muscle and lives.
In an analysis led by the University of Michigan ...
Megabladder mouse model may help predict severity of pediatric kidney damage
2013-09-05
A new study of the megabladder mouse model suggests that tracking changes in the expression of key genes involved in kidney disease could help physicians predict the severity of urinary tract obstruction in pediatric patients, which could help identify children at the greatest risk of chronic kidney disease and permanent organ damage. The work was led by a team that includes Brian Becknell, MD, PhD, a clinician and assistant professor in the Division of Nephrology at Nationwide Children's Hospital.
The research, which tracked the expression of a number of genes related ...