Diabetes is one of the most common chronic diseases among middle-aged and elderly individuals. Current research indicates that diabetic patients are prone to cognitive issues such as dementia. Many people with diabetes express confusion: How did diabetes become a disease that "affects the head"? Clinical studies suggest the increased risk of dementia in diabetics stems primarily from the following factors.Diabetes can affect both large cerebral arteries and small cerebral arteries and microvessels, leading to vascular blockages that impair cerebral blood supply or cause strokes. Chronic cerebral ischemia can damage conduction fibers, disrupting connections between cortical and subcortical structures and impairing cognitive function. Increased blood-brain barrier permeability in diabetic patients also allows immune cells and mediators to migrate into the brain, participating in neurodegenerative processes and affecting brain function.
2. Glycotoxicity.Prolonged hyperglycemia can disrupt neuronal metabolism, protein synthesis, and gene expression, accelerating neuronal degeneration and cortical atrophy. Additionally, hyperglycemia creates hyperosmolar conditions in brain tissue interstices. This is particularly detrimental in elderly brains with atherosclerotic changes, as it promotes the release of harmful tissue factors (e.g., tumor necrosis factor, interleukins) that damage brain tissue structure, ultimately causing cognitive impairment.
3. Insulin Resistance. Insulin resistance elevates serum insulin levels and reduces tissue sensitivity to insulin, leading to metabolic abnormalities. This impairs the brain's clearance of dementia-specific neurotoxic substances like β-amyloid and tau proteins. Their accumulation can cause brain dysfunction or atrophy.
4. Hypoglycemia. Brain tissue relies on glucose for energy metabolism. During hypoglycemia, the brain's access to glucose energy is disrupted, impairing brain function. Furthermore, the process of correcting hypoglycemia can inflict secondary damage, exacerbating neuronal death in the cerebral cortex and hippocampus. Recurrent hypoglycemia may cause memory decline, slowed reactions, or even dementia.