Type 3 Diabetes and Alzheimer's Disease
Type 3 diabetes is a term proposed by some researchers who suggest that Alzheimer's disease, a form of dementia, may be triggered by insulin resistance in the brain. Insulin resistance refers to the body's inability to respond properly to insulin hormone. Diabetes may lead to reduced brain responsiveness to insulin, which is crucial for fundamental tasks, including memory and learning, potentially increasing the risk of Alzheimer's disease among diabetes patients.
This hypothesis is based on the following observations:
Alzheimer's disease and Type 2 diabetes share some underlying mechanisms, including issues related to insulin resistance in the brain and dysfunction of insulin-like growth factors. Some general symptoms of Alzheimer's disease may be related to the "Type 3 diabetes" hypothesis:
Memory loss: This is typically the first and most prominent symptom, initially affecting short-term memory and progressing to long-term memory loss.
Difficulty in thinking and reasoning: Problems with planning, concentrating, and problem-solving may become apparent.
Language difficulties: Difficulty finding words, using incorrect words, or understanding conversations is common.
Changes in personality and behavior: Emotional fluctuations, confusion, irritability, and withdrawal from social activities may occur.
Loss of independence: As the disease progresses, individuals may require assistance with daily activities such as bathing, dressing, and eating.
Due to these symptoms, some experts refer to Alzheimer's disease as a form of diabetes.
It's a well-established fact that individuals with Type 2 diabetes have a higher risk of developing Alzheimer's disease. One possible reason is reduced blood flow to the brain due to damaged blood vessels, which impairs the supply of essential nutrients to the brain.
Impaired insulin signaling in the brain may contribute to the accumulation of abnormal proteins, such as amyloid plaques and tau tangles, which are characteristic of Alzheimer's disease.
Additionally, a genetic variant associated with Alzheimer's disease, known as APOE4, appears to interfere with brain cells' ability to use insulin, potentially leading to cell starvation and death. Individuals with the APOE4 genetic variant have approximately 10 to 15 times higher risk of developing Alzheimer's disease.
A recent clinical study conducted at the Mayo Clinic tested whether delivering insulin through intranasal spray could improve symptoms of Alzheimer's disease. While the results of this phase 2 clinical trial showed a slowdown in cognitive decline even if improvement was not observed, it holds promise.
Although the results of these phase 2 clinical trials are encouraging, the exact connection between Alzheimer's disease and diabetes is still under research.