Advanced Kidney Disease May Get Overlooked in Individuals With CP

Advanced kidney disease is associated with death for individuals with cerebral palsy (CP) independent of related factors, such as cancer and cardiovascular conditions, according to the results of a new study conducted by Michigan Medicine.

Investigators say physicians might be missing early signs of kidney disease by overestimating kidney function, despite using standard methods of measurement.

“The current clinic methods to assess kidney function are influenced by muscle mass in a way that provides an inaccurate picture of kidney health for patients with cerebral palsy,” Daniel Whitney, PhD, assistant professor of physical medicine and rehabilitation at Michigan Medicine, said in a statement.

Investigators analyzed data from 16,700 individuals with CP, 7.3% of whom had kidney disease. They found kidney disease was associated with higher mortality, especially end-stage kidney disease.

When testing for kidney function, physicians focus on creatinine, a waste product of the muscle. They measure the amount of creatinine, with higher amounts equaling worse kidney function. Creatinine is also used to define the stages of kidney disease.

Investigators note that the problem arises because individuals with CP have low muscle mass and naturally have lower creatinine levels, so when the blood test is performed, it reflects more on the low muscle mass instead of how well the kidney is functioning.

This could be a reason that physicians often think kidney function in individuals with CP is better than it is.

“We don’t necessarily need to re-invent the wheel when it comes to using standard clinical tests to measure organ health,” Whitney said in the statement. “But, for people with cerebral palsy and other disabilities, we need to figure out how to better utilize these tests and their values to capture the individual’s true organ health and function.”

Investigators also question whether poor kidney health could be associated with the increased risk of cardiovascular disease.

The study results were published in Frontiers in Neurology.