Kidney Week 2013: New approaches to assessing and protecting kidney health

(Press-News.org) Contact information: Kurtis Pivert
kpivert@asn-online.org
202-699-0238
American Society of Nephrology
Kidney Week 2013: New approaches to assessing and protecting kidney health Atlanta, GA (November 7, 2013)—A variety of recent studies highlight new approaches to assessing and protecting kidney health. Below are the findings of some of these studies, which are being presented at ASN Kidney Week 2013 November 5-10 at the Georgia World Congress Center in Atlanta, GA.

In one study, Viviane Calice da Silva, MD (Pró-Rim Foundation, in Brazil) and her colleagues evaluated the potential of using a dipstick that determines saliva urea nitrogen (SUN) levels for diagnosing acute kidney injury (AKI)—an abrupt decline in kidney function—in 44 patients with varying stages of kidney damage. (Urea is a waste product excreted by the kidneys, intestine, saliva, and sweat. Urea nitrogen tests measure the amount of nitrogen that comes from urea.) The researchers found that the SUN dipstick was comparable to standard blood urea nitrogen tests, and the dipsticks accurately discriminated different stages of AKI. They noted that the technique could be particularly useful in areas with limited access to clinical chemistry facilities. "This low-resource technology may help to improve the diagnosis of advanced AKI and aid triaging patients in areas with limited access to healthcare facilities and may improve outcomes," they wrote. "The next step is to repeat this research with a 7-day follow-up to see if the strip is able to show the difference during the days according to the treatment applied."

Another team led by Minesh Khatri, MD (Columbia University) looked at the effects of the Mediterranean diet on kidney health in 900 adults without kidney disease who were followed for an average of 6.9 years. "The Mediterranean diet has received much attention recently for having possible cardiovascular health benefits. Considering there is a close link between cardiovascular and kidney disease, it is conceivable that this dietary pattern may have a beneficial effect on kidney function as well," explained Dr. Khatri. The researchers found that every one-point increase in adherence to the Mediterranean diet (based on a nine point scoring system) was associated with a 17% decreased odds of developing chronic kidney disease during the study and a 14% decreased odds of being in the upper quartile of kidney function decline. "Since observational studies like this have limited ability to detect causality, the next research step would be to have a controlled clinical trial where subjects are randomized to receiving a Mediterranean diet versus a controlled diet," said Dr. Khatri.

Jeanie Park, MD (Emory University School of Medicine and Atlanta VA Medical Center) and her colleagues looked at how fueling the brain, rather than the body, may impact kidney health. Specifically, they examined the effects of mindfulness meditation, a type of stress reduction technique, on blood pressure and adrenaline levels in patients with chronic kidney disease and high blood pressure. They conducted the study because patients with kidney disease are at significantly increased risk of dying from heart disease, in part due to high blood pressure and high adrenaline levels. In their study, 13 patients with stage 3 chronic kidney disease received both mindfulness meditation and blood pressure education, but at different visits. The rate of reduction in systolic blood pressure, diastolic blood pressure, average arterial pressure, and muscle sympathetic nerve activity was significantly greater over time during mindfulness meditation sessions compared with blood pressure education sessions. "Future research will determine if mindfulness meditation has long-term beneficial effects on blood pressure, adrenaline levels, and mortality in patients with kidney disease," said Dr. Park.

Finally, Bjoerg Thorsteinsdottir, MD (Mayo Clinic) and his team looked at the potential burdens of renal replacement therapy—such as dialysis—on elderly patients. Their study included 379 patients aged 75 years and older who were treated at the Mayo Clinic between 2007 and 2011. Most (75%) started renal replacement therapy in the hospital because of an acute illness or surgery. "Loss of independent living was frequently observed following hospitalization," said Dr. Thorsteinsdottir. Specifically, of 254 patients who came from home, 28% died in the hospital or were discharged to hospice, and only 37% were able to return home. Thirty-nine percent of patients died within 6 months of starting treatment; most of these initiated treatment in the intensive care unit while patients who started dialysis as outpatients had reasonably good survival. "Patient awareness of these outcomes may allow for better informed discussions," said Dr. Thorsteinsdottir.

### Highlights A simple saliva test may be used to diagnose kidney injury. A Mediterranean-style diet is associated with a reduced risk of kidney disease and slows the rate of kidney function decline. Mindfulness meditation has beneficial effects on blood pressure and adrenaline levels in patients with kidney disease. Initiation of dialysis can cause considerable burdens and loss of independence for elderly patients.

Study: Spit It out To Check Your Kidneys: Saliva Urea Nitrogen Dipstick as a New Bedside Diagnostic Tool of Acute Kidney Injury (Abstract FR-PO001) Disclosures: Mary Carter has an ownership interest in Fresenius Medical Care. John Callegari has an ownership interest in Fresenius Medical Care. Nathan W. Levin is a consultant for RoFAR, Roche, Aethlon, Fibrogen, Affymax; has an ownership interest in Fresenius Medical Care NA; and receives honoraria from RoFAR, Roche, Fibrogen, Aethlon. Peter Kotanko has an ownership interest in and receives research funding from Fresenius Medical Care. Roberto Pecoits-Filho is a consultant for Baxter Healthcare, Roche; receives research funding from Roche, Genzyme, Baxter Healthcare; and honoraria from Abbott, Roche.

Study: The Impact of a Mediterranean Style Diet on Kidney Function (Abstract SA-OR052) Disclosures: Clinton Wright is a consultant for Merck and receives honoraria from UpToDate. Mitchell S. V. Elkind is a consultant for BMS-Pfizer Partnership and Biogen IDEC; and receives research funding from diaDexus, Inc. and from BMS-Sanofi Partnership. The authors report receiving funding from the National Institute of Neurological Disorders and Stroke.

Study: Mindfulness Meditation Lowers Muscle Sympathetic Nerve Activity and Blood Pressure in Chronic Kidney Disease Patients (Abstract FR-PO501) Disclosures: The authors report receiving support from the NIH and Veterans Affairs.

Study: Starting dialysis at age 75 years or older—outcomes data to help in shared decision making (Abstract FR-OR043) Disclosures: Amy W. Williams receives research funding from Aksys Inc., NxStage Inc., and honoraria from 3M.

ASN Kidney Week 2013, the largest nephrology meeting of its kind, will provide a forum for 14,000 professionals to discuss the latest findings in renal research and engage in educational sessions related to advances in the care of patients with kidney and related disorders. Kidney Week 2013 will take place November 5 – 10, 2013 in Atlanta, GA.

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Founded in 1966, and with more than 14,000 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.