PATIENTS diagnosed with Type 2 diabetes (T2D) at a younger age face a significantly higher risk of developing dementia, particularly those who also have obesity, according to a new study led by researchers at the NYU Rory Meyers College of Nursing, New York, USA. These findings emphasise the urgent need for strategies addressing both conditions to prevent cognitive decline later in life.s
The study highlights a troubling trend as T2D becomes increasingly common among younger individuals. “Our research suggests there may be cognitive consequences to earlier onset T2D, pointing to the need for preventative measures targeting both diabetes and obesity,” commented the study’s lead author.
Although the mechanisms linking diabetes to dementia remain unclear, experts suggest that high blood sugar, insulin resistance, and inflammation may contribute to cognitive decline. Dementia risk rises steeply with earlier diabetes diagnoses: adults diagnosed before age 50 were 1.9 times as likely to develop dementia as those diagnosed at 70 or older. Those diagnosed between 50–59 and 60–69 years were also significantly more likely to develop dementia, with risks increasing by 1.9% for every year earlier the diabetes diagnosis occurred.
The findings stem from an analysis of data from the Health and Retirement Study, a University of Michigan-led longitudinal survey of U.S. adults. Researchers followed 1,213 participants aged 50 and older who had T2D but no dementia at the start of the study. Over 14 years, 216 participants (17.8%) developed dementia.
Importantly, obesity amplified the risk of dementia for those diagnosed with diabetes at a younger age. “Individuals with obesity diagnosed before 50 faced the highest risk in our study,” said the team. They also pointed out the importance of targeting obesity through lifestyle changes or medication to mitigate dementia risk.
As one in five people with T2D globally is under 40, the findings highlight the need for comprehensive public health measures to tackle the growing burden of diabetes and its cognitive consequences. “This research offers critical insights into how age and obesity intersect with diabetes to influence long-term brain health,” said the researchers.
Reference
Qi X et al. Age at diagnosis of diabetes, obesity, and the risk of dementia among adult patients with type 2 diabetes. PLoS One. 2024;19(11):e0310964.
