Greater Changes in Blood Sugar and Blood Pressure Increase Risk of Dementia

Confirming the Relationship Between Blood Glucose Variability and Vascular Dementia
Severe Blood Pressure Fluctuations Affect Alzheimer's Disease

A study has found that to prevent dementia, it is important to manage blood sugar and blood pressure so that their fluctuations are not too large.

On the 22nd, the Korea Disease Control and Prevention Agency's National Institute of Health conducted a survey of 688 individuals, including cognitively normal people and patients with mild cognitive impairment, and found that increased blood sugar variability was associated with severe cerebral white matter lesions and greater accumulation of amyloid protein in the brain.

White matter lesions refer to damage to the brain's white matter, which is a collection of nerve fibers that transmit information between brain regions. This damage occurs due to problems in the brain's microvasculature, leading to impaired blood flow or oxygen supply. Additionally, beta-amyloid in the brain is the main component of senile plaques, a pathological feature specifically observed in the brains of Alzheimer's dementia patients, and is a substance that induces dementia.

High blood sugar variability indicates poor blood sugar control, which tends to increase when meal times are irregular or when consuming high-carbohydrate or simple sugars.

The research team explained, "Increased blood sugar variability is associated with risk factors for Alzheimer's disease and vascular dementia, suggesting that it may lead to neurodegenerative changes and cognitive impairment."

Similarly, greater variability in blood pressure (both systolic and diastolic) was found to increase tau accumulation in the brain, and higher diastolic blood pressure variability was linked to more severe hippocampal atrophy.

In a repeated blood pressure measurement study involving 1,952 participants without dementia, the researchers found that higher average systolic blood pressure was associated with increased amyloid accumulation in the brain. This aligns with previous studies showing that elevated systolic blood pressure can cause microvascular damage in the brain and that damage to the blood-brain barrier (BBB) can induce beta-amyloid accumulation.

Moreover, higher average systolic and diastolic blood pressures were associated with an increased risk of cerebral white matter lesions, and greater variability in systolic and diastolic blood pressure was linked to increased tau accumulation. Tau is the main component of neurofibrillary tangles, a pathological feature specifically observed in the brains of Alzheimer's dementia patients, which accumulates inside nerve cells and is known to be a major cause of cell death.

Greater variability in diastolic blood pressure was also associated with more severe hippocampal atrophy, which is interpreted as blood pressure variability causing unstable cerebral blood flow and damaging brain structures, including the hippocampus.

Professor Seo Sang-won of Samsung Medical Center, who led the study, said, "This research highlights the importance of managing blood sugar and blood pressure effectively for dementia prevention. It is necessary to properly manage not only the levels of blood sugar and blood pressure but also to minimize their fluctuations to prevent cognitive decline."