We know that type 1 and type 2 diabetes affects our brains, and it can increase the risk for dementia. Now, new research finds an even greater risk for all-cause dementia by 2 to 2.5 times higher when you have diabetes.

Dr. Jeffrey Klingman, chief of neurology at Kaiser Permanente, says that the higher chance of developing cognitive impairment and dementia is often linked to microvascular damage – damage to small blood vessels – which is directly related to diabetes. Studies show that in addition to loss of nerve cells, there is also a change in the way brain cells work when someone has diabetes. The higher the blood sugars are, on average, the higher the risk. Plus, repeated low blood sugar, or hypoglycemia, is also associated with cognitive decline. We know that the risk of cognitive decline increases with age, as does the risk for diabetes. That’s another reason why these problems may go hand in hand. Obesity and sleep are also associated with brain issues, but there are very few studies that tease apart these different factors that relate to brain decline.  Diabetes and its complications can accelerate cognitive decline, making patients especially vulnerable to mental impairment and dementia as they age. Diabetes detrimentally affects brain structure and function. Its effects on cognition are due at least in part to macrovascular disease, microvascular changes, hyperlipidemia, alterations in insulin homeostasis, and inflammation. And the relationship between hypoglycemia and dementia may be bidirectional.

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