High cholesterol may increase the risk of Alzheimer's

Having high cholesterol can increase your risk of Alzheimer's. This has been confirmed by a study published in the Journal of the American Medical Association Neurology, which reflected the link between having high cholesterol and degenerative disease. The results will help doctors understand how the disease develops and what its possible causes are, including genetic variation.

"The big question is if there is a causal link between blood cholesterol levels and the risk of Alzheimer's disease, "he says. Thomas Wingo, neurologist and researcher and main author of the study, in a press release collected by 'Europa Press'. "The existing data has been confusing at this point, and an interpretation of it tells us that LDL (or bad) cholesterol plays a causal role, if that is the case, we may need to review the LDL cholesterol targets to help reduce the LDL cholesterol. Alzheimer's risk.Our work now it focuses on checking if there is a causal link. "

Alzheimer's disease is considered "early onset" when it appears before the age of 65

In this way, there is a relationship between having high levels of cholesterol and Alzheimer's, may be due to genetic factors linked to the substance known to clog the arteries. In previous research it was shown that an important risk factor for neurological degenerative disease is a specific mutation of a gene called APOE, the largest single known genetic risk factor to date to explain the neurological pathology.

It is known that this variant of APOE, called APOE E4, raises levels of circulating cholesterol, particularly low density lipoprotein (LDL). This type of cholesterol is commonly called "bad cholesterol" because the high LDL levels they can cause an accumulation of cholesterol in the arteries. Although Alzheimer's is late onset, it seems to be related to this substance present in our body.

After analyzing the blood samples, subjects with high levels of bad cholesterol were more likely to have Alzheimer's disease

The disease is considered "early onset" when it appears before reaching 65 years of age and only conforms 10% of the cases. Previous studies have shown that the condition is based largely on genetics, which means that It is likely to be inherited if a parent has it. It is known that three specific genetic variants interfere (nicknamed PP, PSEN1 and PSEN2). The APOE E4 is also a risk factor in this form of the disease. These variants account for approximately 10% of cases of early onset, which means that 90% of cases remain unexplained.

To assess whether early-onset Alzheimer's is related to cholesterol and to identify the genetic variants that could be the cause of this possible association, scientists sequenced specific genomic regions of 2,125 people, 654 of whom had Alzheimer's early onset and 1,471 belonged to the control group. They also analyzed blood samples from 267 participants to measure the amount of bad cholesterol.

In this way, they found that the genetic variant APOE E4 explained about 10% of early-onset Alzheimer's. Regarding the APP, PSEN1 and PSEN2 factors, the researchers discovered that only 3% were assigned to this cause. After analyzing the blood samples, the scientists found that participants with high LDL levels were more likely to have early onset Alzheimer's disease, compared to patients with lower cholesterol levels. This was true even after the researchers controlled the cases with the APOE mutation, which means that cholesterol could be an independent risk factor for the disease.

As for the good cholesterol (HDL, high density lipoproteins), the scientists discovered that it did not affect the onset of early onset degenerative disease, only a very slight relationship with triglyceride levels. These cases of Alzheimer's were also greater in the participants with a rare variant of a gene called APOB, which encodes a protein that is involved in the metabolism of lipids or fats. Although the study sheds light on possible risk factors for the disease, researchers believe that more studies are still needed to fully explain the connection between neurological pathology and cholesterol.