There is significant research that suggests a connection between type 2 diabetes and Alzheimer’s disease. Many studies do suggest that individuals with type 2 diabetes are at a higher risk of developing Alzheimer’s disease or other forms of neurological diseases.

Research is still not very clear on whether undertaking steps in preventing or controlling type 2 diabetes may reduce your risks of undergoing cognitive decline. However, there are certain connections still seen between the two diseases. Therefore, here we will talk in-depth about how diabetes and Alzheimer’s is linked. 

Diabetes Mellitus And Alzheimer’s Disease: The Connection

Firstly, one of the primary pathophysiological mechanisms that eventually unites both type 2 diabetes and Alzheimer’s disease is insulin resistance. Insulin receptors tend to reduce during the course of normal ageing, with much fewer receptors in those with Alzheimer’s. 

Insulin has several functions within the brain – maintaining satiety, cognition (including memory), and synaptic plasticity (for example, formation of new neural connections when it comes to memory). Hence, disruption to insulin signalling within your brain may lead to cognitive impairment that is seen in those with Alzheimer’s as well as other neurological conditions.

Secondly, the human brain is not the sole organ responsible for the production and containment of beta-amyloid, which is one of the primary Alzheimer’s proteins. The pancreas is also known to produce beta-amyloid, which is generally released alongside insulin. Beta-amyloid’s toxic effects in the pancreas will eventually lead to progressive disruption in the regulation of glucose in those with type 2 diabetes. This surge in amyloid may be more frequent in those with both Alzheimer’s and type 2 diabetes, rather than just those with diabetes. 

Pancreatic amyloid doesn’t seem to have an impact when it comes to overall cerebral amyloid levels. However, in those individuals with high cerebral amyloid levels, this does seem to have a correlation with the onset and duration of type 2 diabetes. That said, this precise relationship needs much more investigation.

Lastly, inflammation is frequently seen in those with obesity, type 2 diabetes, and Alzheimer’s. The presence of inflammation, caused by type 2 diabetes and/or obesity or cardiovascular disease, maybe partly attributable to inflammation in the brain. 

Individuals with higher inflammation tend to demonstrate more cognitive deficits in comparison with those with lower inflammation in both the brain and body. 

When it comes to animal studies, those fed with a high-fat diet tend to demonstrate a significant increase in inflammation within cortical and hypothalamic regions. Combatting obesity, type 2 diabetes, and metabolic disorders may cause a reduction in systemic and cerebral inflammation, thus reducing the severity of cognitive impairment in those with Alzheimer’s.

It is not yet completely clear as to which of these effects best explains the relationship between diabetes and Alzheimer’s disease. However, it is extremely likely that they work together in increasing the risk.

Reducing The Risk

Cost-benefit analysis has not yet offered support for widespread screening of diabetes. However, evidence does support the need to screen individuals at risk. 

Through preventing the onset, delaying the progression, and successfully managing the established cases of diabetes, several medical complications of type 2 diabetes can be eventually reduced, including the risk of cognitive decline. 

Established cases of dementia among diabetic individuals (whether primarily Alzheimer’s disease or other causes) are presently treated based on the standards for the care of dementia that are added to concurrent treatments approached for type 2 diabetes. 

In the future, the established connection between type 2 diabetes and dementia may successfully promote an increase in the exploration of treatments for dementia, which exploit the effects of insulin on the brain. 

Insulin is presently being investigated as a treatment for Alzheimer’s, with some researchers considering it to be a form of “diabetes of the brain.” Moreover, preliminary trials have measured the positive cognitive effects of intranasal (nasal) insulin. Intranasal insulin is not yet available as a treatment for Alzheimer’s disease because clinical trials are still in progress.

On A Final Note

Doctors do not know yet what are the causes of Alzheimer’s disease or the precise manner in which diabetes and Alzheimer’s are connected. However, they do know that high blood sugar or insulin can cause damage to the brain in numerous ways. 

Reference Links:

• https://www.news-medical.net/health/Does-Type-2-Diabetes-Increase-the-Risk-of-Alzheimers-Disease.aspx
• https://www.alz.org/national/documents/latino_brochure_diabetes.pdf
• https://www.mayoclinic.org/diseases-conditions/alzheimers-disease/in-depth/diabetes-and-alzheimers/a
• https://www.brightfocus.org/alzheimers/article/diabetes-modifiable-risk-factor-alzheimers-disease