A 2020 study found that kidney disease increases the risk of having tiny brain hemorrhages called microbleeds. People with kidney disease were five times more likely to have microbleeds than those with normal kidney function.

Researchers studied the effects of kidney disease on cultured brain endothelial cells and in mice. They also tracked the progression of microbleeds in people who had kidney disease or were healthy.

They found that exposing the cells to urea – a byproduct of protein metabolism that builds up in the blood during kidney disease – damaged the endothelial cells' integrity, compromising their capacity to maintain the blood-brain barrier. The mice with kidney disease had twice as many microbleeds in their brains as healthy mice and showed signs of increased blood-brain barrier permeability. Fifty percent of the people who had kidney disease had microbleeds, whereas just 10 percent of those who were healthy had microbleeds.

Microbleeds are cerebral microhemorrhages that occur due to cerebral amyloid angiopathy, chronic hypertension, and other vascular conditions. Having a high microbleed count is associated with impaired cognitive function. Microbleeds are a hallmark of cerebral small vessel disease.

Evidence suggests that omega-3 fatty acids reduce the risk of chronic kidney disease. Omega-3 fatty acids may protect the kidneys by improving endothelial function, reducing blood pressure, and maintaining healthy blood lipids. Learn more about the benefits of omega-3s in our overview article.

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