Cardiac biomarker indicates fluid overload in dialysis patients

May 27, 2010

Nephrologists must consider fluid overload effects when prescribing dialysis, according to a study appearing in an upcoming issue of the Clinical Journal of the American Society of Nephrology (CJASN). The fluid overload biomarker, N-terminal pro-brain-type natriuretic peptide (NT-pro-BNP), previously known as a “cardiac biomarker” in dialysis patients, is an important component of managing patients with kidney disease.

Fluid overload can cause misleading increases in body weight. “Assessment of dry or target weight is a fundamental concept in managing patients with end stage kidney disease, as volume overload leads to cardiac dysfunction and increased risk of death,” explains Andrew Davenport, MD (University College London Medical School). Dry weight is the patient’s weight without the extra fluid that builds up between sessions.

“Our study did not show any sustained association between NT-proBNP and cardiac function,” comments Davenport. The results contrast with previous studies suggesting that NT-proBNP might be a useful biomarker to predict increased risk of cardiovascular events and death in patients with . BNP is a produced by overworked or damaged heart ventricles and accompanied by the loss of sodium through urine. A biomarker is a that indicates progression of disease or response to medical therapy.

Dialysis patients with may still have high NT-proBNP levels, according to an accompanying editorial by Patrick S. Parfrey, MD (Memorial University, St. John’s, Newfoundland, Canada). However, when cardiac tests show normal heart function, “high BNP levels are likely the result of blood volume expansion, and require reduction in post dialysis dry weight,” Parfrey writes.

Though this “cardiac biomarker” now appears to be more closely related to fluid status than to heart function, an association with heart dysfunction was found in those who had a history of hypertension and were taking beta blockers. High NT-proBNP levels might also indicate malnutrition, another common problem in dialysis patients.

The researchers measured NT-proBNP levels after a dialysis session in 72 stable dialysis patients. The patients also underwent tests of . NT-proBNP levels were most associated with indicators of fluid overload. Maintaining proper fluid balance is one of the essential functions of dialysis. Excess fluid in the body―also called fluid overload or volume overload―can lead to the development of heart failure.

The study is limited by the fact that it was cross-sectional (all data collected at one time) rather than longitudinal (data collected over a period of time), according to Davenport.

Explore further: 11th Sierra Leonean doctor dies from Ebola

More information: The article, entitled “N-terminal proBNP—Marker of Cardiac Dysfunction, Fluid Overload, or Malnutrition in Hemodialysis Patients?” (doi 10.2215/CJN.09001209) and editorial, entitled “BNP in Hemodialysis Patients” (doi 10.2215/CJN.02710310) will appear online on May 27, 2010.

add to favorites email to friend print save as pdf

Related Stories

Dialysis safe for kidney patients' heart health

Jul 09, 2009

Dialysis treatments do not affect the heart health of kidney disease patients who have had a heart attack, according to a study appearing in an upcoming issue of the Clinical Journal of the American Society Nephrology (CJASN ...

Low thyroid function common in chronic kidney disease

Jun 11, 2008

Many patients with chronic kidney disease (CKD) have mild reductions in thyroid function, or subclinical hypothyroidism—a condition that becomes more common as kidney function declines, according to a study in the September ...

Sleeping through dialysis: No nightmare for kidney patients

May 21, 2009

Dialysis takes hours of kidney disease patients' time several days a week, so why not do it at night while sleeping? Overnight dialysis is more convenient for some patients and offers significant benefits over shorter daytime ...

Recommended for you

11th Sierra Leonean doctor dies from Ebola

8 minutes ago

One of Sierra Leone's most senior physicians died Thursday from Ebola, the 11th doctor in the country to succumb to the disease, a health official said.

In the battle against Ebola, a double-layer solution

34 minutes ago

When working with Ebola patients, protective gear works, but removing it can be harrowing. Seeking to protect health care workers from the precarious nature of taking off soiled gloves, Cornell students have ...

New hope for rare disease drug development

11 hours ago

Using combinations of well-known approved drugs has for the first time been shown to be potentially safe in treating a rare disease, according to the results of a clinical trial published in the open access Orphanet Journal of ...

Three weeks since last Ebola case in Mali: WHO

14 hours ago

Mali has not had a case of Ebola for three weeks, the World Health Organization said Wednesday, completing one of the two incubation periods the country needs to be declared free of the virus.

Migraine may double risk for facial paralysis

15 hours ago

Migraine headache may double the risk of a nervous system condition that causes facial paralysis, called Bell's palsy, according to a new study published in the December 17, 2014, online issue of Neurology, the medical journa ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.