Simple blood test identifies persons at highest risk for kidney disease complications

December 16, 2010

An infrequently used blood test can effectively identify individuals at increased risk of developing complications associated with chronic kidney disease (CKD), according to a study appearing in an upcoming issue of the Journal of the American Society Nephrology (JASN). Use of this simple test might help physicians identify persons with CKD who are at high risk for complications, and identify persons with impaired kidney function at earlier stages of disease.

To assess kidney function, doctors most often measure an individual's level of creatinine in the blood. Creatinine is produced by muscles and filtered by the kidneys. Unfortunately, creatinine tests are inaccurate at detecting mild kidney impairment, and creatinine levels can vary with muscle mass and protein intake. Recently, cystatin C blood measurements have emerged as an alternative test of kidney function. Because the protein is removed from the bloodstream by filtration in the kidneys, cystatin C levels rise in the blood when kidney function declines.

Carmen A. Peralta, MD, MAS, Michael G. Shlipak, MD, MPH (San Francisco Veteran's Affairs Medical Center and University of California, San Francisco) and their colleagues studied the ability of cystatin C levels to identify impaired kidney function. Their study included 11,909 participants from the Multi-Ethnic Study of Atherosclerosis (MESA) and the Cardiovascular Health Study (CHS), two studies designed to investigate various aspects of cardiovascular disease. The investigators defined CKD using both creatinine and cystatin C and compared their links to higher risks for premature death, cardiovascular events, heart failure, and kidney failure--all of which are known complications of CKD.

In MESA, 9% of individuals had CKD by a creatinine-based equation only, 2% had CKD by a cystatin C-based equation only, and 4% had CKD by both equations. In CHS, these percentages were 12%, 4%, and 13%, respectively. Compared with those without CKD, individuals in MESA with CKD based on creatinine only had similar risk of premature death, while individuals with CKD based on cystatin C only had more than a 3-fold increased risk, and those with CKD based on both had nearly a 2-fold increased risk. In CHS, individuals with CKD based on creatinine only also had a similar risk of premature death compared with those without CKD, while individuals with CKD based on cystatin C only had a 1.78-fold increased risk, and those with CKD based on both had a 1.74-fold increased risk. The pattern was similar for cardiovascular disease, heart failure, and kidney failure.

The authors concluded that among adults diagnosed with CKD using the creatinine-based equation, poor prognosis is limited to patients who also have CKD according to the cystatin C-based equation. Therefore, cystatin C may have an important role in distinguishing the persons suspected of having CKD, based on the current creatinine definition, who have the highest risk for CKD complications. In addition, cystatin C may identify persons with high risk for CKD complications who are currently missed by creatinine.

"Our findings suggest that the creatinine-based CKD definition captures a large number of adults who are actually at low risk for important complications of CKD. Based on our findings, we believe that cystatin C should be a confirmatory test among persons identified as having impaired kidney function based on creatinine levels," said Dr. Peralta. She noted that in doing so, individuals at highest risk may benefit the most from aggressive treatment and specialty referral. In addition, many other persons whose CKD is not confirmed by cystatin C may be reassured that they have low risk for CKD complications. Future research should investigate the cost-effectiveness of using multiple markers to identify and risk-stratify CKD.
-end-
Study co-authors include Ronit Katz, DPhil, Ian De Boer, MD, David Siscovick, MD (University of Washington); Mark Sarnak, MD, Andrew Levey, MD (Tufts-New England Medical Center); Joachim Ix, MD (University of California San Diego); Linda Fried, MD (Pittsburgh Veteran's Affairs Medical Center); and Walter Palmas, MD (Columbia University).

Disclosures: The authors reported no financial disclosures.

The article, entitled "Cystatin C Identifies Chronic Kidney Disease Patients at Higher Risk for Complications" will appear online at http://jasn.asnjournals.org/ on December 16, 2010, doi 10.1681/ASN.2010050483.

The content of this article does not reflect the views or opinions of The American Society of Nephrology (ASN). Responsibility for the information and views expressed therein lies entirely with the author(s). ASN does not offer medical advice. All content in ASN publications is for informational purposes only, and is not intended to cover all possible uses, directions, precautions, drug interactions, or adverse effects. This content should not be used during a medical emergency or for the diagnosis or treatment of any medical condition. Please consult your doctor or other qualified health care provider if you have any questions about a medical condition, or before taking any drug, changing your diet or commencing or discontinuing any course of treatment. Do not ignore or delay obtaining professional medical advice because of information accessed through ASN. Call 911 or your doctor for all medical emergencies.

Founded in 1966 and comprised of more than 12,000 members, the American Society of Nephrology (ASN) leads the fight against kidney disease by educating health professionals, sharing new knowledge, advancing research, and advocating the highest quality care for patients.

American Society of Nephrology

Related Heart Failure Articles from Brightsurf:

Top Science Tip Sheet on heart failure, heart muscle cells, heart attack and atrial fibrillation results
Newly discovered pathway may have potential for treating heart failure - New research model helps predict heart muscle cells' impact on heart function after injury - New mass spectrometry approach generates libraries of glycans in human heart tissue - Understanding heart damage after heart attack and treatment may provide clues for prevention - Understanding atrial fibrillation's effects on heart cells may help find treatments - New research may lead to therapy for heart failure caused by ICI cancer medication

Machining the heart: New predictor for helping to beat chronic heart failure
Researchers from Kanazawa University have used machine learning to predict which classes of chronic heart failure patients are most likely to experience heart failure death, and which are most likely to develop an arrhythmic death or sudden cardiac death.

Heart attacks, heart failure, stroke: COVID-19's dangerous cardiovascular complications
A new guide from emergency medicine doctors details the potentially deadly cardiovascular complications COVID-19 can cause.

Autoimmunity-associated heart dilation tied to heart-failure risk in type 1 diabetes
In people with type 1 diabetes without known cardiovascular disease, the presence of autoantibodies against heart muscle proteins was associated with cardiac magnetic resonance (CMR) imaging evidence of increased volume of the left ventricle (the heart's main pumping chamber), increased muscle mass, and reduced pumping function (ejection fraction), features that are associated with higher risk of failure in the general population

Transcendental Meditation prevents abnormal enlargement of the heart, reduces chronic heart failure
A randomized controlled study recently published in the Hypertension issue of Ethnicity & Disease found the Transcendental Meditation (TM) technique helps prevent abnormal enlargement of the heart compared to health education (HE) controls.

Beta blocker use identified as hospitalization risk factor in 'stiff heart' heart failure
A new study links the use of beta-blockers to heart failure hospitalizations among those with the common 'stiff heart' heart failure subtype.

Type 2 diabetes may affect heart structure and increase complications and death among heart failure patients of Asian ethnicity
The combination of heart failure and Type 2 diabetes can lead to structural changes in the heart, poorer quality of life and increased risk of death, according to a multi-country study in Asia.

Preventive drug therapy may increase right-sided heart failure risk in patients who receive heart devices
Patients treated preemptively with drugs to reduce the risk of right-sided heart failure after heart device implantation may experience the opposite effect and develop heart failure and post-operative bleeding more often than patients not receiving the drugs.

How the enzyme lipoxygenase drives heart failure after heart attacks
Heart failure after a heart attack is a global epidemic leading to heart failure pathology.

Novel heart pump shows superior outcomes in advanced heart failure
Severely ill patients with advanced heart failure who received a novel heart pump -- the HeartMate 3 left ventricular assist device (LVAD) -- suffered significantly fewer strokes, pump-related blood clots and bleeding episodes after two years, compared with similar patients who received an older, more established pump, according to research presented at the American College of Cardiology's 68th Annual Scientific Session.

Read More: Heart Failure News and Heart Failure Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.