Hemodialysis Blog – Hemodialysis.com

Highlights

• Among individuals with chronic kidney disease, African Americans experience faster progression of the disease during later stages compared with other races.
• Screening of African Americans with chronic kidney disease can help improve care and is cost-effective.

Chronic kidney disease affects an estimated 26 million adults in the United States.

Washington, DC (November 29, 2012) — Among individuals with chronic kidney disease (CKD), African Americans experience faster progression of the disease during later stages compared with other races, according to a study appearing in an upcoming issue of the Journal of the American Society of Nephrology (JASN). Also, screening of African Americans with CKD can help improve care and is cost-effective.

It is well known that African Americans have a similar prevalence of CKD as other Americans, but they are more likely to progress to kidney failure. The lifetime incidence of kidney failure is about 8.6% for African Americans compared with 3.5% for other Americans. The reasons for this disparity are not known.

To investigate, Thomas Hoerger, PhD (RTI International) and his colleagues used a simulation model of CKD progression to see if the prevalence of common CKD risk factors (such as high blood pressure and diabetes) could explain the higher lifetime incidence of kidney failure among African Americans.

The researchers found that the higher lifetime incidence of kidney failure among African Americans was not fully explained by the prevalence of common CKD risk factors. Instead, it could be explained by faster progression of CKD among African Americans during the later stages of the disease.

The investigators then considered whether screening for a particular marker of CKD called microalbuminuria—when the kidneys leak small amounts of protein into the urine—would be cost-effective. (Screening could lead to earlier treatment that might prevent kidney failure.) “We found that screening for microalbuminuria is cost-effective for African Americans at either five- or 10-year intervals, particularly for those with diabetes or hypertension,” said Dr. Hoerger.

Kidney failure affected more than 571,000 US adults and cost more than $42 billion in 2009.

Study co-authors include John Wittenborn, Xiaohui Zhuo, PhD, Meda Pavkov, MD, PhD, Nilka Burrows, Paul Eggers, PhD, Regina Jordan, Sharon Saydah, PhD, and Desmond Williams, MD, PhD.

Source Eurekalert 11/29/2012

November 29 2012

Highlights

• For kidney failure patients with blocked arteries surrounding the heart, open heart surgery is linked with a lower risk of dying or having a heart attack compared with angioplasty.
• Among patients undergoing these revascularization procedures, the five-year survival of patients without kidney disease is over 90%, but survival in kidney failure patients is dismal.

Heart disease is the leading cause of death in patients with kidney failure. Coronary heart disease affects 30% to 60% of kidney failure patients.

Washington, DC (November 29, 2012) — Among the two available procedures for opening blocked arteries surrounding the heart, one appears to be safer than the other for dialysis patients, according to a study appearing in an upcoming issue of the Journal of the American Society of Nephrology (JASN). The findings may help lead to better care for kidney failure patients with coronary heart disease.

While 30% to 60% of kidney failure patients on dialysis have blocked arteries surrounding the heart, there is little information regarding how to optimally fix the life-threatening problem in these individuals. That’s because dialysis patients have been excluded from clinical trials on the two available procedures: open heart surgery (coronary artery bypass grafting, or CABG) and angioplasty (percutaneous coronary intervention, or PCI).

Tara Chang, MD, Wolfgang Winkelmayer, MD, ScD (Stanford University School of Medicine) and their colleagues examined a database of all patients on dialysis in the United States with primary Medicare coverage to determine which is the best revascularization strategy: CABG or PCI. They identified nearly 22,000 dialysis patients who underwent CABG or PCI between 1997 and 2009.

Among the major findings:

• Overall survival rates were poor, with five-year survival rates of 22% to 25% irrespective of revascularization strategy. (Five-year survival rates in patients without kidney disease are over 90%.)
• CABG was associated with a 13% lower risk of death and a 12% lower risk of either dying or having a heart attack.

“It is important to note that because our study was observational, our results cannot prove that CABG is better; only a randomized trial can do that,” said Dr. Chang. “However, our study does offer guidance to patients and providers who must make these tough decisions and suggests that in carefully selected patients on dialysis with multivessel coronary heart disease, CABG may be preferred rather than PCI.” Because organizing a randomized trial of CABG and PCI in patients on dialysis would be quite difficult, observational studies such as this one may be the best way to compare the two strategies.

Study co-authors include David Shilane, PhD, Dhruv Kazi, MD, Maria Montez-Rath, PhD, and Mark Hlatky, MD.

Disclosures: The authors reported no financial disclosures.

Source: Eurekalert

Studies investigate aspects of nutrition and blood pressure control in chronic kidney disease patients

Highlights

• Adding fruits and vegetables to the diet improves kidney disease patients’ health.
• Poor nutrition plays a role in the link between poverty and kidney disease.
• Among kidney disease patients, Blacks are more likely to have uncontrolled blood pressure than Whites

Three studies presented during the American Society of Nephrology’s Annual Kidney Week provide new information on diet and blood pressure in kidney disease patients.

Nimrit Goraya, MD (Texas A&M College of Medicine) and her colleagues investigated whether adding fruits and vegetables to the diet can improve the health of patients with chronic kidney disease (CKD). Alkaline therapy is used to treat CKD patients with severe metabolic acidosis (when there is too much acid in the body). Dr. Goraya and his team looked to see if adding fruits and vegetables—which are highly alkaline—can benefit CKD patients with less severe metabolic acidosis. For the study, 108 patients were randomized to receive added fruits and vegetables, an oral alkaline medication, or nothing. After three years, consuming either fruits and vegetables or the oral medication reduced a marker of metabolic acidosis and preserved kidney function to similar extents.

“Our findings suggest that an apple a day keeps the nephrologist away,” said Dr. Goraya.

Another team led by Deidra Crews, MD (Johns Hopkins University School of Medicine) wondered whether poor dietary habits might help explain why poverty is linked with CKD. In their study of 2,058 individuals, fiber, calcium, magnesium, and potassium intake were lower, and cholesterol higher, among those in poverty. CKD was present among 5.6% of people in poverty, and 3.8% of those not in poverty.

“An unhealthy diet is strongly associated with kidney disease among poor individuals. Dietary interventions tailored to meet the needs of this population may help to reduce disparities in kidney disease,” said Dr. Crews.

A third study looked at blood pressure control among ethnically diverse CKD patients. Racial and ethnic minorities are more likely to develop kidney failure than whites, perhaps due in part to poorer blood pressure control. Delphine Tuot, MD (University of California, San Francisco) and her colleagues examined blood pressure using 18,864 clinical blood pressure measurements from 6618 adults (23% white, 34% black, 18% Hispanic, 21% Asian) with CKD who received primary care in a health network serving San Francisco’s uninsured and publicly insured residents. Blood pressure was nearly 20% higher than national estimates with smaller, though still significant, disparities between black and white patients (with blacks having higher rates of uncontrolled blood pressure.)

“Public health care delivery systems like the Community Health Network of San Francisco disproportionately care for vulnerable patients, including those of racial/ethnic minorities, and can serve as front-line agents to reduce disparities of care through implementation of innovative programs,” said Dr. Tuot.

Study co-authors for “Fruits and Vegetables or Oral NaHCO3 Preserve GFR and Reduce Urine Angiotensinogen, a Marker of Kidney Angiotensin II Activity, in Stage 3 CKD” (abstract 2214) include Chanhee Jo, PhD, Jan Simoni, PhD, and Donald E. Wesson, MD.

Study co-authors for “Dietary Habits, Poverty, and Chronic Kidney Disease in an Urban Population” (abstract 842) include Marie Kuczmarski, PhD, Edgar R. Miller, MD, PhD, Alan B. Zonderman, PhD, Michele Kim Evans, MD, and Neil R. Powe, MD.

Study co-authors for “Blood Pressure Control among CKD Patients in a Public Health System” (abstract 2303) include Charles E. McCulloch, PhD, Chi-yuan Hsu, MD, Tanushree Banerjee, PhD, Margaret Handley, PhD, Dean Schillinger,and Neil R. Powe, MD.

Disclosures available at http://www.asn-online.org/press/.

ASN Kidney Week 2012, the largest nephrology meeting of its kind, will provide a forum for 13,000 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 2012 will take place October 30 – November 4 at the San Diego Convention Center.

The content of these studies 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 with more than 13,500 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.

Two new studies from the Johns Hopkins Bloomberg School of Public Health and the Chronic Kidney Disease Prognosis Consortium found that the presence of chronic kidney disease itself can be a strong indicator of the risk of death and end-stage renal disease (ESRD) even in patients without hypertension or diabetes. Both hypertension and diabetes are common conditions with chronic kidney disease with hypertension being the most prevalent. The studies were released online in advance of publication in The Lancet.

Chronic kidney disease affects 10 to 16 percent of all adults in Asia, Europe, Australia and the United States. Kidney function is measured by estimating glomerular filtration rate and kidney damage is often quantified by measuring albumin, the major protein in the urine standardized for urine concentration.

In the hypertension meta-analysis, low kidney function and high urine protein was associated with all-cause and cardiovascular mortality and ESRD in both individuals with and without hypertension. The associations of kidney function and urine protein with mortality outcomes were stronger in individuals without hypertension than in those with hypertension, whereas the kidney function and urine protein associations with ESRD did not differ by hypertensive status.

In the diabetes analysis, individuals with diabetes had a higher risk of all-cause, cardiovascular mortality and ESRD compared to those without diabetes across the range of kidney function and urine protein. Despite their higher risks, the relative risks of these outcomes by kidney function and urine protein are much the same irrespective of the presence or absence of diabetes.

“Chronic kidney disease should be regarded as at least an equally relevant risk factor for mortality and ESRD in individuals without hypertension as it is in those with hypertension,” said Bakhtawar K. Mahmoodi, MD, PhD, lead author of the hypertension analyses.

“These data provide support for clinical practice guidelines which stage chronic kidney disease based on kidney function and urine protein across all causes of kidney disease. The conclusions are strengthened by the findings of leading studies and the participation of investigators from 40, countries and a detailed analysis of over 1 million participants,” said Josef Coresh, MD, PhD, MHS, the Consortium’s principal investigator and professor in the Bloomberg School’s Department of Epidemiology.

“Association of kidney disease measures with mortality and end-stage renal disease in individuals with and without hypertension: a meta-analysis” (lead author, Bakhtawar K. Mahmoodi, MD, PhD, from the Johns Hopkins Bloomberg School of Public Health and University Medical Center Groningen, the Netherlands) and “Association of kidney disease measures with mortality and end-stage renal disease in individuals with and without diabetes: a meta-analysis” (lead author Caroline Fox, MD, from the Framingham Heart Study) were written by the Chronic Kidney Disease Prognosis Consortium (CKD-PC), which includes approximately 200 collaborators and data from 40 countries.

Renal transplantation is best treatment option for improving quality of life in people with late-stage chronic kidney disease

In people with late-stage chronic kidney disease, renal transplantation is the best treatment option to improve quality of life, but for those receiving dialysis, home-based automated peritoneal dialysis (in which fluids are infused into the abdominal cavity and can be done nightly at home) provides a better quality of life than continuous ambulatory peritoneal dialysis (a type of dialysis performed continuously throughout the day), according to a study by Australian researchers published in this week’s PLOS Medicine.

The researchers, led by Melanie Wyld from the University of Sydney, reviewed and assimilated all of the available published evidence to investigate whether quality of life in people with late-stage chronic kidney disease (as measured by utilities—a numerical value measured on a 0 to 1 scale [where 0 represents death and 1 represents full health] of the strength of an individual’s preference for specified health-related outcomes) differed according to treatment type.

In their analysis, which represented over 56,000 patients, the researchers found that the average utility for those who had a renal transplantation was 0.82, followed by the pre-dialysis group (0.79), patients treated with dialysis (0.70), and finally, patients receiving conservative care (0.62). When comparing the type of dialysis, the researchers found that there was no significant difference in utilities between haemodialysis and peritoneal dialysis, but patients using automated peritoneal dialysis had, on average, a higher utility (0.80) than those treated with continuous ambulatory peritoneal dialysis (0.72).

In addition to helping to inform economic evaluations of treatment options, the information from this analysis can help guide clinicians caring for patients with chronic kidney disease in their discussions about possible treatment options.

The authors conclude: “Our results suggest that automated peritoneal dialysis, a home-based form of dialysis that accounts for just 7% of dialysis patients in the UK and 4% of dialysis patients in the United States, has a significantly higher mean utility than continuous ambulatory peritoneal dialysis.”

Commenting on the findings, the authors said: “The finding that transplant patients’ utilities increased significantly between the 1980s and the 2000s likely reflects improvements in transplant care and evolving clinical practice.”

They add: “We found that patients who chose conservative care had significantly lower quality of life than patients treated with dialysis, although the number of studies was small.”

Funding: No specific funding was received for this study. MW was supported by a summer scholarship stipend. RM was supported through National Health and Medical Research Council grants #457281 and #571372. AH was supported through a National Health and Medical Research Council grant #633003. KH and AW were personally salaried by their institutions during the period of writing (though no specific salary was set aside or given for the writing of this paper). No funding bodies had any role in the study design, data collection, analysis, decision to publish or preparation of the manuscript.

Competing Interests: The authors have declared that no competing interests exist.

Citation: Wyld M, Morton RL, Hayen A, Howard K, Webster AC (2012) A Systematic Review and Meta-Analysis of Utility-Based Quality of Life in Chronic Kidney Disease Treatments. PLoS Me