New data findings suggest that people who develop type 2 diabetes before age 60 years are at threefold greater risk for dementia compared to those who don’t develop diabetes. The data from the prospective Atherosclerosis Risk in Communities (ARIC) cohort also suggest that the previously identified increased risk for dementia among people with prediabetes appears to be entirely explained by the subset who go on to develop type 2 diabetes.

Of the 11,656 ARIC participants without diabetes at baseline in 1990-1992 (age 46-70 years), 20.0% had prediabetes (defined as A1c 5.7%-6.4% or 39-46 mmol/mol). During a median follow-up of 15.9 years, 3143 participants developed diabetes. The proportions of patients who developed diabetes were 44.6% among those with prediabetes at baseline versus 22.5% of those without.

Dementia developed in 2247 participants over a median follow-up of 24.7 years. The cumulative incidence of dementia was 23.9% among those who developed diabetes versus 20.5% among those who did not.

This new study is the first to examine the effect of diabetes in the relationship between prediabetes and dementia, as well as the age of diabetes onset on subsequent dementia.

Read the full article here.