Alzheimer’s disease and other forms of dementia (ADD) have emerged as significant threats to global public health. These chronic, progressive disorders of the central nervous system not only cause devastating cognitive decline, such as the heart – wrenching inability of relatives to recognize each other, but also rank as the fifth leading cause of death worldwide. Currently, the medical community still grapples with the lack of effective prevention and treatment strategies, making understanding the risk factors associated with these diseases all the more critical.
China’s Alarming ADD Burden and Identified Risk Factors
A recent study by Professor Geng Daoying’s team at Huashan Hospital, affiliated with Fudan University, and published in the journal PLOS One, has shed light on China’s significant ADD disease burden. The research, based on data from the Global Burden of Disease 2021 (GBD 2021), analyzed the disease burden and risk factors among individuals aged 40 and above.
The findings reveal that China bears a heavier ADD disease burden compared to most countries, with a growth rate that outpaces the global average. From 1990 to 2021, the ADD disease burden in China tripled, while the global burden only doubled during the same period. Gender differences were also evident, as both in China and globally, women exhibited higher incidence and prevalence rates of ADD. The disease was found to be most common among those aged 80 – 84, with its incidence and prevalence peaking between 65 and 69 years and continuing to rise with advancing age.
Among the identified risk factors for ADD – high fasting blood glucose, high body mass index (BMI), and smoking – hyperglycemia emerged as the dominant factor in both China and globally in 2021, regardless of gender.
The Mechanisms Behind High Blood Sugar’s Impact on Brain Cognition
High blood sugar can disrupt cognitive function in the brain through multiple complex pathways. Insulin resistance, a common consequence of high blood sugar, inhibits the activity of insulin – degrading enzymes in the brain. This leads to the accumulation of beta – amyloid protein, a characteristic feature of Alzheimer’s disease. In a vicious cycle, the deposition of beta – amyloid protein may further exacerbate insulin deficiency and resistance in the brain.
As a result, patients with insulin resistance often experience impairments in various cognitive domains, including orientation, memory, attention, and calculation.Long – term chronic hyperglycemia also takes a toll on the brain by affecting neural synapse formation, intensifying oxidative stress responses, and causing direct damage to brain cells. It activates the TLR4 signaling pathway, triggering the release of inflammatory factors and promoting neuroinflammation, which in turn damages peripheral neurons.
Additionally, high blood sugar leads to damage of vascular endothelial cells, causing blood vessels to narrow and harden. This reduction in blood flow to the brain impairs normal neuronal function. Microcirculation disorders associated with high blood sugar further disrupt the nutrient supply to neurons, negatively impacting cognition. Recurrent hypoglycemia, often a side effect of insulin or hypoglycemic drug use, can also damage neurons and contribute to cognitive decline. Moreover, diabetic patients may experience structural changes in the gray and white matter of the brain, and diabetes can disrupt the balance of neurotransmitters essential for cognitive function.
Early Detection, Treatment, and Prevention Strategies for Diabetic Patients
For diabetic patients, early detection of dementia signs is crucial. Symptoms such as frequent forgetfulness of recent events, sleep disturbances, difficulty locating everyday items, inability to perform simple tasks like cooking or cleaning, getting lost in familiar places, loss of interest in previously enjoyed activities, and noticeable personality changes, such as increased suspicion, sensitivity, and mood swings, should prompt a visit to the hospital for a “memory check – up”.
Regarding treatment options, certain hypoglycemic drugs show potential in reducing the risk of dementia. Metformin, for example, may offer neuroprotective benefits for cognitive dysfunction, although the exact mechanism remains unclear. Some studies have reported a slight increase in dementia incidence among long – term metformin users, potentially linked to vitamin B12 deficiency caused by the drug. The impact of thiazolidinedione (TZD) on cognitive dysfunction in diabetes is still under investigation, but it may positively influence cognitive function by improving metabolic control and insulin levels. Glucagon – like peptide – 1 receptor agonists (GLP – 1RA) can cross the blood – brain barrier, and a recent study in JAMA Neurol in April 2025 showed that GLP – 1RA – based hypoglycemic therapy is associated with a significant reduction in all – etiology dementia.
To prevent Alzheimer’s disease, diabetic patients are advised to actively manage their blood sugar levels, avoiding both hyperglycemia and hypoglycemia. Tailoring blood glucose control targets according to individual health conditions is essential. Regular screening for cognitive dysfunction, especially for those over 65 or with risk factors like anxiety, depression, recurrent hypoglycemia, unexplained falls, or difficulty in self – blood sugar management, is highly recommended, using methods such as neuropsychological assessment and magnetic resonance imaging.
Adopting a healthy lifestyle, including strict diet control, increased physical exercise, following a Mediterranean – style diet rich in olive oil, vegetables, fruits, fish, seafood, and beans, maintaining a regular biological clock, and quitting smoking and limiting alcohol intake, can significantly reduce the risk of cognitive dysfunction. Engaging in continuous learning, mental training through activities like playing Go, chess, bridge, or Sudoku, and maintaining active social interactions are also key strategies to preserve brain cognitive function and prevent the onset of Alzheimer’s disease.
