Individuals with elevated levels of cholesterol are more likely to develop Alzheimer’s disease compared to other people, researchers from Kyushu University in Fukuoka, Japan, wrote in the journal Neurology. Kensuke Sasaki, MD, PhD wrote that there was a close association between high cholesterol levels and brain plaques, also known as senile plaques, which themselves are common among patients with Alzheimer’s disease.
Dr. Sasaki and team tested cholesterol levels of 2,587 individuals who had no signs of Alzheimer’s disease. They were aged from 40 to 79.
After a long observation period of 10 to 15 years, they examined the bodies of 147 people who had died. 34% (50) of them had been diagnosed with dementia while they were alive.
They looked for tangles and plaques in the brain – both hallmark signs of Alzheimer’s disease. Plaques are a build-up of amyloid, a protein which occurs between nerve cells, while tangles are an accumulation of tau, another protein which occurs within the cells.
Amyloid beta immunostaining showing senile plaques
Those with a cholesterol reading above 5.8 mmol/L had considerably more brain plaques than those with lower or normal cholesterol levels.
They authors revealed that plaques were found in . . . :
- . . . . 86% of those with high cholesterol levels
- . . . . 62% of those with low cholesterol levels
No association was found between cholesterol levels and the likelihood of having tangles.
In a previous study, Sasaki had discovered that insulin resistance was linked to the presence of brain plaques.
Sasaki said:
“Our study clearly makes the point that high cholesterol may contribute directly or indirectly to plaques in the brain, but failed treatment trials of cholesterol-lowering drugs in Alzheimer’s disease means there is no simple link between lowering cholesterol and preventing Alzheimer’s.”
Written by Christian Nordqvist