Study links chronic kidney disease to rising cognitive impairment

An advancing of chronic kidney disease may be linked to an increase in cognitive impairment, such as problems with attention, processing speed and executive function, according to a study.

The findings, published in The Journal of the American Medical Association (JAMA) Network Open, underscores that severity of chronic kidney disease could be a risk factor for cognitive decline.

Chronic kidney disease is a long-term, progressive loss of kidney function -- where kidneys are not able to purify blood -- often lasting more than three months.

Researchers, including those from Tulane University in the US, examined over 5,600 participants aged 21-79, analysing blood and urine samples for kidney function, and a cognitive function assessment for brain function over six years.

 

"In this cohort study of 5,607 participants with CKD (chronic kidney disease), a higher urinary protein to creatinine ratio (in a urine test) was associated with impairments in attention and processing speed as well as executive function," the authors wrote.

They said that studies are looking at physiological processes linking chronic kidney disease with cognitive dysfunction, with some suggesting credible hypotheses.

The team suggested that because chronic kidney disease can exacerbate hypertension, consequences of the condition's progression could explain the increased risk of cognitive impairment experienced among patients.

Evidence also suggests that vascular links with dementia may be more prominent among patients with long-term kidney dysfunction, compared with the general population, they said.

The researchers added that accounting for clinical factors, including hypertension, did not entirely explain the link between chronic kidney disease and cognitive decline, indicating that other mechanisms may be involved.

Chronic kidney disease-related conditions, such as abnormal bone mineral metabolism, chronic inflammation and oxidative stress, sleep disorders and anaemia, may also contribute to the observed associations between kidney and brain health as shown in prior studies, the authors said.