By Dave DeFusco

Managing an intricate balance between sodium intake, blood pressure and the volume of bodily fluid is key to minimizing the risk of further harm to individuals with end-stage kidney disease, according to a paper co-authored by Dr. Jochen Raimann, an industry professor in the Katz School’s M.S. in Biotechnology Management and Entrepreneurship.

Published in Frontiers in Medicine, the paper “The Role of Intra- and Interdialytic Sodium Balance and Restriction in Dialysis Therapies,” evaluates the impact of diet, medication and methods of dialysis treatment on patient outcomes, with a specific emphasis on blood pressure control, weight gain between dialysis sessions and symptoms during dialysis.

Dr. Raimann, who is also a physician-scientist and senior director of data analytics at the Renal Research Institute in New York City, collaborated with researchers from George Washington University, Loyola University Chicago, the University of New Mexico, the University of California, San Francisco, and academic institutions in the Netherlands and Turkey.

“The review explores various sources of sodium exposure for dialysis patients, including dietary salt intake, medication administration and the dialysis treatment itself,” said Dr. Raimann. “Understanding the various sources of sodium is essential for managing its impact on a patient's health.”

While salt intake is typically too high in the general population, individuals with healthy kidneys possess physiological mechanisms to prevent the excessive accumulation of salt and associated health problems. The kidneys and other organ systems, such as the gastrointestinal tract and skin, play a crucial role in sodium regulation. In kidney failure, a disrupted sodium balance can lead to an overload of fluid in the body, resulting in elevated blood pressure.

Hypertension resulting from an increase in volume in the fluid compartment outside the body’s cells, also called extracellular volume, is associated with the risk of heart attack, heart failure and stroke, as well as an increase in risk of mortality in dialysis patients.

The researchers argue that restricting dietary sodium is challenging, especially in Western societies, where a significant portion of sodium comes from processed foods. While there is a lack of data from randomized trials, dialysis centers in France and Turkey that have restricted dietary salt reported increased survival rates and a reduced need for anti-hypertensive medications.

The study further points out the importance of addressing socioeconomic disparities in diet quality, emphasizing that education and household income levels significantly affect salt intake and hypertension risk.

“Collaboration with the food industry is crucial for successful salt-reduction programs,” said Dr. Raimann. “Few countries have implemented effective strategies in spite of the fact that salt restriction has shown positive effects on survival and reduced health care costs.”