New Study Finds Link Between High Cholesterol and Alzheimer’s Disease

There is a wide variety of health problems in the United States, especially seeing as how less than 5% of American adults get 30 minutes of exercise each day. And as people age, the risk of health problems increases. Alzheimer’s disease is a common concern for people later in life — and a new study has now found a link between high cholesterol and Alzheimer’s.

Researchers with the Atlanta Veterans Affairs Medical Center and Emory University found a possible link between early-onset Alzheimer’s disease, which is a rare form of Alzheimer’s, and LDL cholesterol levels. LDL cholesterol is the “bad” type of cholesterol, which can result in fatty deposits building up and causing heart problems, like heart disease and strokes.

For the study, the researchers looked at 267 blood samples from the Alzheimer’s Disease research centers at Emory University and University of California. They specifically looked at the cholesterol levels in the blood samples along with sequencing the genes of 2,125 people. Of these people, 654 had early-onset Alzheimer’s and the rest of the samples were the control group.

When looking at the samples, the researchers found a connection not only between high levels of LDL and Alzheimer’s, but a link between a genetic mutation of the APOE gene, called APOE E4, and Alzheimer’s. APOE E4 is known to increase levels of cholesterol, including LDL.

The data showed that participants with higher LDL cholesterol levels were, in fact, more likely to have early-onset Alzheimer’s. Additionally, about 10% of early-onset Alzheimer’s cases were linked with APOE E4. The authors of the study say the risk linked to LDL is not related to the risk connected with the APOE E4 mutation.

Another finding of the study was that the number of early-onset Alzheimer’s cases was higher among participants with a rare variation of the gene APOB. This gene plays a role in creating lipids, which includes cholesterol. This means there is also a link between the APOB mutation and the risk of early-onset Alzheimer’s.

Jana Voigt, head of research at Alzheimer’s Research UK, was not directly involved with the study, but agrees that there is substantial evidence to show a link between early-onset Alzheimer’s and high cholesterol.

Voigt explained, “This study cannot tease apart cause and effect, but it does show that early-onset Alzheimer’s is associated with cholesterol genes. Alzheimer’s Research UK is funding research into how cholesterol may contribute to Alzheimer’s and whether drugs might be able to tackle these processes. Despite a link between Alzheimer’s risk and cholesterol, clinical trials of cholesterol-lowering statins have not shown benefits for treating or preventing Alzheimer’s.”

While there are currently around 5.7 million Americans who are affected by Alzheimer’s, early-onset Alzheimer’s only impacts around 200,000 people in the United States, significantly reducing the chance of treating the rare form of the disease.

So high cholesterol is not only a risk factor for heart conditions, but now dementia, too. To stay as healthy as possible, people, especially those in their 40s and 50s, should get plenty of exercise and maintain a healthy diet. Furthermore, those four out of five older people who take at least one daily medication should talk to their doctors about how their medications impact their heart health.

The study has been published in the journal JAMA Neurology.