How does obesity affect the risk of developing Alzheimer's?
Avoiding obesity in young and middle age can obviously protect us from developing Alzheimer's in later life. Obesity and obesity are actually more of a risk factor for heart disease and stroke, but researchers have now found that obese people were also more likely to have elevated levels of amyloid. This sticky protein forms the so-called plaques in the brain of people with Alzheimer's.
The researchers at the Johns Hopkins University School of Medicine in Baltimore found that obesity can lead to an increased risk of Alzheimer's. A healthy aging of the brain is based on the health of the heart and blood vessels at a young age, the researchers explain. Overweight and obesity are bad for the heart and blood vessels, and for this reason obesity also increases the risk of developing Alzheimer's. The doctors published the results of their study in the journal "Journal of the American Medical Association".
Experts examine obese subjects with diabetes
For their study, the scientists examined the deposition of amyloid in the brains of the elderly. The participating subjects had previously smoked in middle age, had high blood pressure, were obese, and suffered from diabetes or high cholesterol, explains the author Dr. Rebecca Gottesman from Johns Hopkins University School of Medicine.
What are the effects of poor vascular health?
The above risk factors can adversely affect the health of a person's blood vessels. If vascular health suffers, this can lead to hardening of the arteries and other disorders, the researchers explain. The current study suggests that middle-aged vascular health can play a direct role in the development of Alzheimer's disease, the authors add.
How do the risk factors affect Alzheimer's risk?
If two or more of the risk factors are present, the risk of large amyloid deposits triples. Experts suspect that so-called amyloid leads to the development of Alzheimer's disease. A risk factor alone increased the probability of amyloid deposits accumulating by 88 percent, the experts write in their study.
Obesity doubles the likelihood of amyloid deposits
Obesity is a particularly strong risk factor for the formation of amyloid deposits. Obesity alone doubles the likelihood that amyloid will build up in later life, doctors say. The sole risk factor of obesity is very interesting, because twenty years ago obesity was not a major problem in society. This suggests that the general problem with Alzheimer's could be much worse in twenty years, the scientists explain.
Doctors examine almost 350 subjects
For the current study, the researchers examined the data from almost 350 people. The subjects' heart health has been tracked since 1987 in an ongoing study, the scientists explain. The average age of the participants at the start of the study was 52 years. Sixty percent of the subjects were women and 43 percent of the participants were African American. The average duration of the follow-up examinations was almost 24 years, say the doctors.
The subjects were examined again two decades later
When the participants started the study, none of them had dementia, the study authors report. Two decades later, the test subjects were asked to be examined again. Doctors checked the brain scans for signs of amyloid. The researchers discovered a connection between heart risk factors and amyloid in the brain. The relationship did not vary among different ethnic groups or known genetic risk factors for Alzheimer's, the experts add. So-called heart risk factors, which emerged late in life, were not associated with amyloid deposits in the brain.
Why does blood vessel health affect the risk of Alzheimer's?
The current study showed no cause-effect relationship. However, there are some theories as to why a person's blood vessels health could be linked to Alzheimer's. Blood and spinal fluid contain amyloid. Some experts suspect that unhealthy blood vessels could release the amyloid from the bloodstream into the brain tissue. Blood vessels also play a role in flushing out broken amyloid particles that occur in a person's brain. If there are errors in the circulation, it could affect the amyloid deposits in some way, the researchers say.
Maintaining health is a lifelong commitment
Hardened arteries can obviously lead to strokes but also to dementia and Alzheimer's, explains author Gottesman. Based on current knowledge, the expert advises protecting brain health by improving heart health. The earlier you start, the better. “Don't wait until you are 60 or older to start taking care of your health. Maintaining health must be a lifelong commitment, ”the authors warn. (as)