Hypercholesterolemia is a condition characterized by abnormally high levels of cholesterol in the blood. The elevated cholesterol is usually caused by an overloaded liver, which produces too much cholesterol to meet the body’s needs.
High levels of cholesterol can lead to serious health issues such as stroke, heart attack and other cardiovascular diseases. Treatment typically involves lifestyle changes such as diet and exercise, and sometimes medication.
Hypercholesterolemia means high blood cholesterol. Cholesterol is a waxy substance that is produced by the liver and present in all cells of the body.
All the cholesterol a person needs is produced in the liver, but another source is dietary cholesterol, which comes from animal foods such as meat, poultry, dairy products, egg yolk and Fish.
These foods are high in saturated fats and trans fats, substances that can cause the liver to produce excess cholesterol and in some cases can lead to high cholesterol.
Cholesterol is needed for various bodily functions, including the synthesis of cell membranes and certain hormones, as well as the production of substances necessary for the digestion of fats. However, too high a cholesterol level can increase the risk of coronary heart disease and atherosclerosis.
Hypercholesterolemia and risk of stroke
Hypercholesterolemia is a medical term to describe having high levels of cholesterol in the blood, which can increase the risk of stroke. Risk factors include age, gender, genetics, lifestyle choices (such as diet), and certain medications. If left untreated, having high cholesterol can lead to an increased risk of stroke due to blockages in the arteries or changes in blood flow.
Consequently, it is important for those with hypercholesterolemia to take measures such as following a healthy diet and engaging regular physical activity.
Hypercholesterolemia and risk of dementia
Preclinical studies carried out in rodents have widely reported the deleterious role of abnormally high levels of cholesterol on neurons. Researchers have hypothesized that high cholesterol increases levels of amyloid in the brain, thereby promoting the onset of Alzheimer’s disease. This hypothesis was verified thanks to neuroimaging techniques highlighting the simultaneous presence of high cholesterol levels and early amyloid deposits in patients aged 40 to 55 years.
The association between hypercholesterolemia and Alzheimer’s is less obvious than it seems, and seems to depend on the age of the subject. Indeed, while epidemiological studies report a link between high cholesterol levels in midlife and an increased risk of dementia, this link disappears when participants reach a later age. Some studies have even reported an elevated risk of dementia in those with low cholesterol levels.
A Belgian study was conducted to clarify these observations by following nearly 1500 healthy women, aged 38 to 60 when they were included in the study, and followed for 32 years.
The first cholesterol measurements were made in 1968-69, and follow-ups at different periods: 1974-75, 1980-81, 1992-93 and 2000-01.
Results
1. Eleven percent of women developed dementia during the 32 years of follow-up.
2. No association between hypercholesterolemia and dementia exists in women who were followed for the maximum period of 32 years, ie in 1968-1969 and 2000-2001.
3. Women who developed dementia had higher than average cholesterol levels only in the first 3 measurements (ie 1968-69, 1974-75 and 1980-81).
4. On the other hand, we observe that a steady drop in cholesterol levels during the follow-up period is associated with an increased risk (+135%) of dementia, but not of Alzheimer’s disease. This decrease in cholesterol levels is linked to a drop in body mass index (BMI). It should be noted that the BMI of women who developed dementia was lower during the last two follow-ups (i.e. in 1992-93 and 2000-01), compared to those who did not develop dementia. .
Source: The 32-year relationship between cholesterol and dementia from midlife to late life. Neurology. 2010;75:1888-1895.