Patients diagnosed with type 2 diabetes before they turn 60 are nearly three times more likely to develop dementia than those without incident diabetes, shows a longitudinal community-based study.

US epidemiologists also reported that dementia risk declined as the age of diabetes onset increased, with a risk of 73% and 23% for those in the 60-69 and 70-79 age groups, respectively.

However, those diagnosed with diabetes when aged 80 or older did not have an excess risk of the neurodegenerative condition compared with those without diagnosis.

“Improving early detection and engagement in people with pre-diabetes to prevent or delay the progression to diabetes may have long-term population benefits for dementia prevention,” the authors reported in Diabetologia.