Increased temperatures contributed to more than 200,000 cases of kidney disease in 15 years in Brazil alone: study

by Monash University

Professor Yuming Guo. Credit: Monash University

Today the world's largest study of the impact of temperature changes and kidney disease reveals that 7.4 percent of all hospitalisations for renal disease can be attributed to an increase in temperature. In Brazil—where the study was focused—this equated to more than 202,000 cases of kidney disease from 2000-2015.

01 nov 2021--The study, led by Professor Yuming Guo and Dr. Shanshan Li, from Planetary Health at Monash University and published in The Lancet Regional Health—Americas journal, for the first time quantifies the risk and attributable burden for hospitalizations of renal diseases related to ambient temperature using daily hospital admission data from 1816 cities in Brazil.

The study comes as the world focuses on the impact of climate change at the COP26 conference in Glasgow from 31 October.

In 2017, a landmark article in The Lancet declared renal diseases a global public health concern, estimating that almost 2.6 million deaths were attributable to impaired kidney function that year. Importantly the incidence of death from kidney disease had risen 26.6 percent compared to a decade previously, an increase that this study may indicate was, in part, caused by climate change.

The study looked at a total of 2,726,886 hospitalizations for renal diseases recorded during the study period. According to Professor Guo, for every 1°C increase in daily mean temperature, there is an almost 1 percent increase in renal disease, with those most impacted being women, children under 4 years of age and those 80+ years of age.

The associations between temperature and renal diseases were largest on the day of the exposure to extreme temperatures but remained for 1–2 days post-exposure.

In the paper the authors—who are also from the University of Sao Paulo—argue that the study "provides robust evidence that more policies should be developed to prevent heat-related hospitalisations and mitigate climate change."

"In the context of global warming, more strategies and policies should be developed to prevent heat-related hospitalizations."

The authors advise interventions should be urgently incorporated into government policy on climate change, including particularly targeting specific individuals, including females, children, adolescents, and the elderly, as they are more vulnerable to heat with regard to renal diseases.

"Moreover, attention should be paid to low- and middle-income countries like Brazil, where reliable heat warning systems and preventive measures are still in need," Professor Guo added.

---

More information: Bo Wen et al, Association between Ambient Temperature and Hospitalization for Renal Diseases in Brazil during 2000–2015: A Nationwide Case-Crossover Study, The Lancet Regional Health - Americas (2021). DOI: 10.1016/j.lana.2021.100101

ASN increases knowledge of geriatric kidney disease

New online curriculum educates physicians about kidney disease in older patients

17 may 2009--The fastest-growing group of patients initiating dialysis is patients 75 years old and older; providing the best care for this group of patients presents significant challenges. The American Society of Nephrology (ASN) introduces the first-ever online curriculum to address aging and the kidney. The curriculum, based on the Accreditation Council for Graduate Medical Education (ACGME)'s six core competences of patient care, medical knowledge, practice-based learning and improvement, interpersonal and communication skills, professionalism, and systems-based practice, answers questions about the management of elderly patients.

Twenty-five percent of institutions with accredited US nephrology training programs do not have accredited geriatric training programs, but the Accreditation Council for Graduate Medical Education (ACGME) has mandated that fellows receive formal training in geriatric nephrology. The ASN online curriculum will serve as a primary source of educational material for geriatric nephrology training nationwide.

Dimitrios G. Oreopoulos, MD, PhD, and Jocelyn Wiggins, BM, BCh served as co-chairs of the Geriatrics Task Force and oversaw development of the curriculum. "Caring for elderly patients with end-stage renal disease (ESRD) is an issue of growing importance. There remain many unanswered questions about the management of elderly patients with ESRD. This text will help nephrologists in training and those in practice improve and refine their approaches to the care of elderly kidney patients," said Dr. Oreopoulos.

A grant was provided by the Association of Specialty Professors (ASP) for this curriculum, which includes 38 chapters on various aspects of geriatric nephrology. The online resources will be expanded over the next few months to include power point presentations that distill the information written in each chapter. The entire curriculum will be freely available for anyone to access and utilize.

ASN understands the importance of treating the geriatric nephrology population and also collaborates with ASP on three additional endeavors:

1. ASN partners with the Association of Specialty Professors (ASP) to offer the ASN-ASP Junior Development Grant in Geriatric Nephrology. Since 2003, ASN and ASP have funded more than seven junior nephrologists who have decided to focus their research careers on issues related to the geriatric aspects of nephrology. In 2008, there were two recipients of this grant, Steven G. Coca, DO, and Lisa M. Nanovic, DO.

2. ASN and ASP collaborated with the National Institutes of Health (NIH) to hold the "ASN-ASP Workshop on Prediction, Progression, and Outcomes of Chronic Kidney Disease in Older Adults." This workshop, which took place in May 2008, was intended to increase NIH funding for the geriatric aspects of nephrology. ASP provided ASN funding for four fellows to attend and participate in the workshop.

3. ASP also provided ASN with a $15,000 grant to fund an In-Depth Nephrology Course focused on the geriatric aspects of nephrology. The course, "Geriatric Nephrology: An Epidemiologic and Clinical Challenge," was held at Renal Week 2008. For 2009, this course will be repeated and will follow the chapters of the geriatric nephrology curriculum listed above. Talks from the 2008 course are available on the ASN website.

###

Founded in 1966, the American Society of Nephrology (ASN) is the world's largest professional society devoted to the study of kidney disease. Comprised of 11,000 physicians and scientists, ASN continues to promote expert patient care, advance medical research, and educate the renal community. ASN also informs policymakers about issues of importance to kidney doctors and their patients. ASN funds research, and through its world-renowned meetings and first-class publications, disseminates information and educational tools that empower physicians.

Simple model predicts those at risk for chronic kidney disease

First such tool will help spur prevention efforts

NEW YORK, 23 dec 2008 -- Traditionally, doctors have had no clear way to predict which of their patients might be headed down the road to chronic kidney disease (CKD). Now, researchers at NewYork-Presbyterian Hospital/Weill Cornell Medical Center and the University of North Carolina at Chapel Hill have created a simple eight-point risk factor checklist to do just that.

As reported in a special double issue (Dec. 8 and 22) of the Archives of Internal Medicine, the model accurately stratifies middle-aged and older patients at high risk for newly diagnosed CKD, which involves a gradual, even fatal loss of kidney function over time.

According to the National Kidney Foundation, 26 million American adults have CKD and millions of others are at increased risk.

"These patients are often battling concurrent conditions such as diabetes or heart disease, so anything we can do to predict and then lower their risk for kidney disease will be invaluable," says study senior author Dr. Phyllis A. August, the Ralph A. Baer Professor of Medical Research at Weill Cornell Medical College, and an internist and nephrologist at NewYork-Presbyterian Hospital/Weill Cornell Medical Center.

In their research, Dr. August and colleagues combined data from two major studies, the Atherosclerosis Risk in Communities trial and the Cardiovascular Health Study, which together total 14,155 men and women aged 45 years or older. All of the participants had a glomerular filtration rate exceeding 60 mL/min/1.73m2 at the beginning of the study -- indicating their kidneys were functioning at a normal healthy level at that time.

The researchers then tracked the health of the participants during a follow-up of up to nine years, recording those participants whose filtration rate fell below the healthy 60 mL/min/1.73 m2 threshold. They also tracked a wide variety of risk factors thought important to the onset of CKD.

Overall, a total of 1,605 participants from the two cohorts went on to develop CKD over the course of follow-up.

"We discovered that a scoring system that included eight key risk factors -- older age, anemia, female sex, hypertension, diabetes, peripheral vascular disease and any history of congestive heart failure or cardiovascular disease -- accurately predicted which of the older patients would proceed to CKD and which would not," says study co-author Dr. Heejung Bang, assistant professor in the Division of Biostatistics and Epidemiology in the Department of Public Health at Weill Cornell Medical College.

In the scoring system, each time a patient answers "yes" to having one of the eight risk factors, they gain anywhere from one to three points. Older age (at or over 70) was of highest predictive significance, so it added three points to the score. Risk factors other than age each added one point.

Scoring a total of just three points in the model captured 70 percent of those patients who would go on to develop CKD over the next 10 years. For people scoring three, the model had 91 percent sensitivity for assessing how well the test identified people who would later go on to develop CKD, and a specificity of 28 percent for assessing how well the test identified those who would not develop the disease. For those scoring a six on the test, sensitivity and specificity were 93 percent and 25 percent, respectively.

"Importantly, we were able to validate the accuracy of the score across different cohorts, suggesting that it remains consistent in a variety of contexts," notes Dr. Abhijit V. Kshirsagar of the University of North Carolina Kidney Center, Chapel Hill, and the study's lead author. "Each of the eight components that make up the score is also easy to identify or quickly assess during any doctor-patient interview. Patients themselves can even self-assess using the tool, and bring their concerns to their doctor, if need be."

This means that physicians may now have valid jumping-off point for discussions of how patients can curb their odds for CKD, a condition that can lead to dialysis, end-stage kidney disease and even death. "Chronic kidney disease is largely preventable if its underlying root causes are caught early and treated," says Dr. Bang. "So it's important to know who's at risk. Our model helps answer that question."

The new algorithm may have an even broader impact. "As it becomes more clear as to just what conditions are the prime factors behind kidney dysfunction -- factors such as diabetes, hypertension and heart disease -- this tool should guide policymakers and researchers to find better and more cost-effective ways to target this devastating disease," notes Dr. August.

###

Co-authors include Dr. Andrew S. Bomback, Dr. Suma Vupputuri, Dr. David A. Shoham, Dr. Philip J. Klemmer of UNC Chapel Hill; and Drs. Lisa M. Kern and Madhu Mazumdar of NewYork-Presbyterian/Weill Cornell and Weill Cornell Medical College, respectively.

The study was supported by a Clinical and Translational Science Award to Drs. Bang and Mazumdar, and by the University of North Carolina Kidney Center.

NewYork-Presbyterian Hospital/Weill Cornell Medical Center

Preventing anemia is important to kidney disease patients' quality of life

Study indicates that FDA statements may need to be revised

13 nov 2008--Maintaining sufficient red blood cell levels is important to the physical and mental health of patients with chronic kidney disease (CKD), according to a study appearing in the January 2009 issue of the Clinical Journal of the American Society Nephrology (CJASN). The findings indicate that preventing anemia in kidney disease patients should be an integral part of their care.

Erythropoiesis-stimulating agents—medications that elevate red blood cell levels (hemoglobin)—have been a topic of controversy lately, and their use in patients with chronic kidney disease has come into question. Recent studies have shown an increased risk of death, blood clots, strokes, and heart attacks in patients with chronic kidney failure when erythropoiesis-stimulating agents are given at higher than recommended doses. (Current recommendations indicate that treatment should not elevate hemoglobin levels over 12 gm/dl). Other studies have found a link between the recommended doses of these drugs and an increased risk of death in patients with cancer and an increased risk of blood clots in patients following orthopedic surgery. In addition, the US Food and Drug Administration stated that the benefits of erythropoiesis-stimulating agents have not been well documented, particularly as they relate to quality of life. These suggestions are disturbing to nephrologists, who believe that these drugs have significantly helped their CKD patients.

To help clarify the issue, Fredric Finkelstein, MD, of the Hospital of St. Raphael and Yale University in New Haven, CT, and his colleagues studied the relationship between hemoglobin levels and health-related quality of life (which includes both mental and physical components) in patients with CKD.

A total of 1,186 patients with stage three to stage five CKD participated in this study, and they were grouped into categories based on their hemoglobin levels (<11>

The study's findings suggest that maintaining hemoglobin levels is important to the health and well-being of patients with CKD. The authors recommend that additional studies should be done to document the changes in quality of life that occur when erythropoiesis-stimulating agents are used to elevate hemoglobin levels in patients with this disease.

More work also is needed to determine when treatment should be initiated and what the hemoglobin target level should be. "The impact of the answers to these questions for the health-related quality of life of chronic kidney disease patients may well be substantial," the authors wrote.

###

The article, entitled "Health-Related Quality of Life and Hemoglobin Levels in Chronic Kidney Disease," is available online at http://cjasn.asnjournals.org and will appear in the January 2009 print issue of CJASN.

Obesity Linked to Hyperparathyroidism in Chronic Kidney Disease

SALEM, Va., Aug. 9 -- Body mass index and secondary hyperparathyroidism are linked in men with moderate to severe kidney disease, though a causal relationship remains uncertain, researchers reported.
The association between BMI and parathyroid levels, found in a study of nearly 500 men, appeared limited to those with features of malnutrition and inflammation, Csaba P. Kovesdy, M.D., of the Salem VA Medical Center here, and colleagues, reported in the September issue of the Clinical Journal of the American Society of Nephrology.
Although obesity has been associated with hyperparathyroidism in patients with normal renal function, the phenomenon was not previously studied in chronic kidney disease, they said.
Because both obesity and hyperthyroidism are complex problems in chronic kidney disease, establishing a relationship between them has potential prognostic and therapeutic implications, they added.
The researchers examined the association between intact parathyroid hormone levels and BMI in 496 male veterans (mean age 69.4, 22.8% black) with chronic kidney disease, stages 2 to 5, who were not yet on dialysis. The estimated glomerular filtration rate (eGFR) was 31.8 ± 11.2 mL/min per 1.73 m2 .
The men were seen at the VA center from January 1990 to June 30, 2005 and were followed until September 2006.
Higher parathyroid hormone levels were associated with higher BMI after adjustment for age, race, diabetes, and serum calcium and phosphorus levels and proved to be independent of these confounders, the investigators said.
A further analysis found that the association was limited to patients with signs of malnutrition and inflammation. Specifically this included patients with lower albumin (P=0.005 for the interaction term) or higher white blood-cell counts (P=0.026 for the interaction term).
This finding may be unique to patients with chronic kidney disease, the researchers said. Besides providing a possible explanation for why parathyroid hormone levels are higher in obese patients, it may also be important for prognostic reasons, because malnutrition and inflammation are among the major complications responsible for poor outcomes in kidney disease.
The mechanism of action behind the observed association between BMI and parathyroid hormone is unclear, the researchers said. Several studies in patients with normal kidney function indicated that higher BMI was associated with elevated parathyroid hormone levels and lower 1,25(OH)2D and 25(OH)D levels.
Also other measurements have shown that hyperparathyroidism was even better correlated with total body fat, compared with BMI, suggesting that adiposity and not simply higher body weight was responsible for the associations.
Possible explanations for these findings include less sun exposure for obese individuals and higher storage of vitamin D in adipose tissue, or a decreased skeletal response to the actions of parathyroid hormone.
Weight loss by obese patients has been shown to lower their parathyroid hormone levels, the researchers added.
This suggests that weight loss might help lower parathyroid hormone levels in kidney disease patients. Another "intriguing" possibility, the researchers proposed, is an opposite direction for cause and effect, namely that higher hormone levels cause accumulation of fat mass and obesity.
Although it is tempting to extrapolate findings from the general population to kidney-disease patients, important differences between the two groups need to be considered, the researchers emphasized. For example, measurements involving more specific markers of nutritional status and inflammation, such as 25(OH)D, C-reactive protein, IL-6 levels, will be necessary to test these hypotheses.
Study limitations included the exclusive use of male patients from a single institution, the small number of black patients, the lack of measured 1,25(OH)2D and 25(OH)D levels and of specific markers of inflammation, and the retrospective study design, which could not demonstrate causality. Therefore, it was not possible to determine whether obesity induces higher parathyroid hormone levels or vice versa.
Also, the underlying mechanisms of action will have to be better characterized, the researchers concluded.
Dr. Kovesday and co-author Kamyar Kalantar-Zadeh, M.D., Ph.D., reported receiving support from the National Institute of Diabetes, Digestive and Kidney Disease. The study was supported by a grant from Abbott Laboratories to Dr. Kovesday. Primary source: Clinical Journal of the American Society of NephrologySource reference: Kovesdy CP, et al "Obesity Is Associated with Secondary Hyperparathyroidism in Men with Moderate and Severe Chronic Kidney Disease" Clin J Am Soc Nephrol;2007:1031-1036.

Freezing Kidney Tumors Effective And Less Expensive Than Laparoscopy

Science Daily — The nonsurgical treatment of kidney tumors – cryoablation – is as effective as the surgical laparoscopic technique in viable candidates. The comparative trial shows that cryoablation results in a slightly lower recurrence rate of the tumor, a shorter hospital stay, no major complications, and a 59.5 percent lower hospital cost than the laparoscopic treatment.
During cryoablation argon gas enters the tip of the probe and extracts heat from the surrounding cells, resulting in an “ice ball” that freezes and kills the tumor. The nonsurgical treatment spares the majority of the healthy kidney tissue and can be repeated as often as needed. This interventional treatment had no major complications as opposed to the surgical group, which experienced complications in six percent of those studied.
The radiologist uses imaging to pinpoint the tumor, and then inserts the cryoprobe through the skin, similar to the way a biopsy is performed. This can be performed under general anesthesia, but is often possible with only local anesthesia and conscious sedation. By using imaging the radiologist can avoid going through any adjacent structures or harming healthy tissue. If necessary, adjacent structures can be displaced prior to the ablation to minimize collateral damage. Laparoscopy, on the other hand, requires general anesthesia, as well as multiple abdominal incisions to allow access for the surgical instruments. It is also associated with a longer recovery time.
http://www.sciencedaily.com/releases/2007/03/070320103508.htm