In one of the most comprehensive studies to date, researchers investigated the cognitive changes brought on by early-stage chronic kidney disease—a disease affecting some 10 percent of American adults. The findings were published in Nephrology Dialysis Transplantation.
“People with kidney disease have increased risk for cognitive impairment – such as visual-spatial memory – and the risk increases with disease progression, but few studies have examined the relationship using an extensive battery of tests,” said the study’s lead investigator, Ms. Rachael Torres, a doctoral student in Temple University College of Public Health.
Ms. Torres and collaborators from Temple, University of Maine and University of Maryland conducted the investigation with 898 participants from the Maine-Syracuse Longitudinal Study. They reported risk for modest and severe impairment in 22 abilities indexing 8 domains of cognitive functioning.
Once the researchers adjusted for demographic differences, people with kidney disease had greater risk for modest impairment in 9 cognitive abilities and greater risk for severe impairment in 4 abilities. Much of this risk disappeared after the researchers adjusted for cardiovascular risk factors, including hypertension and cardiovascular disease. According to Ms. Torres “this is not surprising, as the cardiovascular system tightly links brain and kidney function.”
The researchers argue that cardiovascular risk factors may be the common link between kidney disease and cognition and that cognitive changes can have implications for how the disease is managed. “Cognitive impairment in the abilities observed could affect a patient’s ability to adjust to changing demands of treatment,” Ms. Torres said. “Treatment becomes increasingly complex as kidney disease progresses, which makes identifying cognitive deficit early in the disease course important.”
In addition to Ms. Torres, researchers in this study included Drs. Merrill Elias and Michael Robbins of the University of Maine, Dr. Stephen Seliger of the University of Maryland and Dr. Adam Davey of Temple
This study was supported by grants (R01HL67358 and R01HL081290) from the National Heart, Lung and Blood Institute, National Institutes of Health and research grant (R01AG03055) from the National Institute on Aging, National Institutes of Health.