Kidneys Might Affect Mental Status As You Age

THURSDAY, Sept. 3, 2020 (HealthDay News) -- Young adults with kidney problems may be at increased risk for mental decline in middle age, a new study suggests.

"Our study shows that if your kidney function starts declining as early as your 30s, you may perform like someone nine years older on certain cognitive tests 20 years later," said study author Sanaz Sedaghat, from Northwestern University Feinberg School of Medicine in Chicago. "Yet many people can have a decline in kidney function without being aware of it."

The study included more than 2,600 people with an average age of 35 at the start of the study. They had blood and urine tests to assess kidney function every five years for 20 years, and the tests were used to estimate their risk of kidney failure at each visit.

Based on the test results, the participants were assigned to three groups: no episodes of kidney failure risk, one episode of kidney failure risk, and more than one episode of kidney failure risk.

At the end of the study period, the participants were given thinking and memory tests.

Over the study's two decades, 427 participants had one or more episodes of kidney failure risk and were in the higher risk group. Controlling for other factors that could affect thinking skills -- such as high cholesterol, high blood pressure and diabetes -- the high-risk group scored an average of four times lower on the end-of-study thinking tests than those with no risk.

The findings were published online Sept. 2 in the journal Neurology.

"Recent studies indicate that even losing just a small amount of kidney function can be toxic for the brain and increase the risk of cognitive decline," Sedaghat said in a journal news release. "Our study adds to the evidence and suggests preserving kidney function in young age needs to be investigated as a potential strategy to keep thinking skills sharp in midlife."

More information

The National Kidney Foundation has more on kidneys.