We know that people with type 2 diabetes face a greater risk of heart disease and stroke, but emerging research also reveals a strong connection between diabetes and dementia.
A recent study of more than 2.3 million people, about 102,000 of them with dementia found that those with type 2 diabetes had a 60 per cent greater risk of developing dementia than people who didn’t have the disease.
The news is even more alarming for women with type 2: They have a 19 per cent greater risk than men of developing vascular dementia, which results from damage to blood vessels.
Researchers are still digging into why women are at greater risk than men, but they do know that diabetes-associated dementia develops through a set of factors including inflammation, insulin resistance, the regulation of blood glucose in the brain, and vascular damage.
High levels of blood glucose can cause damage to blood vessels, whether the vessels surround the heart or the brain.
Uncontrolled diabetes may increase dementia risk because the brain requires intact blood flow to function well. Though more research is needed, there’s also evidence that diabetes may have a role in the development of amyloid plaques (sticky buildup that accumulates outside neurons) associated with Alzheimer’s disease.
According to an analysis data from 150 late-middle-aged adults with a family history of Alzheimer’s but no signs of cognitive impairment. They found that even mild insulin resistance was associated with lower cerebral glucose metabolism, especially in areas of the brain related to memory and executive functioning, a skill set that helps you plan, organise and make judgment calls.
Certain brain areas tend to need more glucose to perform high-demand tasks, like the frontal lobe and mental activities such as juggling your day and reasoning. Higher insulin resistance may have a moderate but at times noticeable impact: Things get forgotten, insights don’t come, and getting through the day is that much harder.
Studies show that obesity and insulin resistance can have immediate negative effects on thinking and memory.
A study published in Neurology illustrates just how quickly diabetes-associated cognitive deficits can happen.
Even more, the people with diabetes’ cognitive test scores which were nine points lower on average than their peers without diabetes, to begin with, fell by 12 per cent, while others’ test scores remained the same. What’s going on here? Loss of blood glucose regulation is partly to blame.
The brain is highly susceptible to fluctuations in blood glucose and it’s the fluctuations that may be even more harmful to the brain than consistently high glucose.
This low-and-high effect can damage cells and nerves and trigger inflammation, which leads to diminished flexibility in the brain’s blood vessels, and in turn, leads to memory loss and difficulty with activities of daily living.
But let’s be clear: Having diabetes or prediabetes doesn’t mean you’re guaranteed to develop dementia. In fact, experts agree that prevention is key to avoiding diabetes-related cognitive impairment. That means monitoring blood glucose levels, managing your diabetes, and maintaining healthy habits.