Pharmacy Daily | Dementia link to earlier onset of T2D

THERE could be an association between type 2 diabetes (T2D)and dementia development later in life, according to international researchers.

New research published in Diabetologia shows an association between T2D and developing dementia in later life, with the risk of dementia increasing the earlier a person develops T2D.

To understand the risks of dementia associated with prediabetes, the authors analysed data from participants of the Atherosclerosis Risk in Communities (ARIC) study.

The cognitive function assessments incorporated data from a scoring system involving three cognitive tests, administered at visits two (1990-1992) and four (1996-1998), the expanded neuropsychological 10-test collection, administered from visit five (2011-2013) onwards and informant interview (Clinical Dementia Rating scale and the Functional Activities Questionnaire).

The Mini-Mental State Examination was also administered.

Participants were followed up with until 2019.

The authors evaluated the association of prediabetes with dementia risk before and after, accounting for the subsequent development of T2D among ARIC participants with prediabetes at baseline.

This was done to understand how much of the association of prediabetes with dementia was explained by progression to diabetes.

They also evaluated whether age at diabetes diagnosis modified the risk of dementia.

Among the 11,656 participants without diabetes at baseline, 2,330 or 20% had prediabetes.

When accounting for diabetes that developed after the baseline period, the authors found no statistically significant association between prediabetes and dementia.

However, they found that the earlier age of progression to T2D had the strongest association with dementia.

There was a three times increased risk of dementia for those developing T2D before age 60 years, falling to a 73% increased risk for those developing T2D aged 60-69 years, and a 23% increased risk for those developing T2D aged 70-79 years.

At ages 80 years or older, developing T2D was not associated with an increased risk of dementia.

The authors said, "prediabetes is associated with dementia risk, but this risk is explained by the development of diabetes.

"Diabetes onset at early age is most strongly related to dementia.

"Thus, preventing or delaying the progression of prediabetes to diabetes will substantially reduce the future burden of dementia."