“Early Onset of Type 2 Diabetes from Prediabetes Increases Risk of Alzheimer’s Disease: Study”

The earlier the age at which prediabetes led to the onset of type 2 diabetes, the higher the risk of Alzheimer’s disease, a new study has found.

Prediabetes refers to a case where fasting blood glucose exceeds the upper limit of the normal range of 99 mg/dL and falls short of the diagnostic criteria for diabetes of 126 mg/dL (100 to 125 mg/dL). Diabetes is diagnosed when it exceeds 127 mg/dL.

A glycated hemoglobin (A1c) of 5.7% to 6.4%, which indicates long-term blood sugar for 2 to 3 months, is also considered prediabetes. Diabetes is diagnosed when the A1c exceeds 6.5%.

In the United States, the adult prediabetic population is up to 96 million. This corresponds to 38% of the adult population.

A research team led by Elizabeth Selvin, professor of epidemiology at Johns Hopkins University School of Public Health, USA, analyzed the data of 11,656 participants in the Atherosclerosis Risk in Communities (ARIC) study and found this fact. HealthDay News reported on the 29th.

They were free of diabetes at the time of study entry, of which 2,330 (20%) were prediabetic.

The research team analyzed whether prediabetes was associated with the risk of dementia by observing the age at which people with prediabetes transitioned to diabetes and the trend of dementia.

As a result, it was found that the earlier the age when prediabetes transitioned to diabetes, the greater the risk of dementia.

When prediabetes transitions to diabetes before the age of 60, the risk of dementia increases threefold.

In comparison, the age at which prediabetes led to diabetes was 73% higher for those aged 60 to 69 years and 23% higher for those aged 70 to 79 years.

If prediabetes progressed and the age of onset of diabetes was over 80 years of age, there was no association with an increased risk of dementia.

These results show that prediabetes is associated with dementia risk, but the reason is in the development of diabetes, the research team explained.

In particular, the earlier the age at which prediabetes leads to diabetes, the stronger the association with the risk of dementia, so preventing or delaying the progression of prediabetes to diabetes will help reduce the risk of developing dementia in the future, the research team pointed out. .

Insulin resistance and hyperglycemia are known to promote the accumulation of beta-amyloid and tau, which are abnormal proteins in brain neurons associated with dementia.

It is known that Alzheimer’s disease occurs when beta amyloid, a surface protein in the space between nerve cells, and tau protein in nerve cells are misfolded and aggregated or tangled, turning into toxic proteins that kill nerve cells.

The results of this study were published in the latest issue of Diabetologia, a journal of the European Association for Study of Diabetes (EASD).

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