An analysis of middle-aged people with type 1 diabetes has revealed a higher prevalence of white matter damage compared with people without the condition, and that these changes are associated with slower cognition.
Researchers from the University of Pittsburgh compared 97 people with type 1 diabetes (mean age, 50 years; mean diabetes duration, 41 years) with 81 people (mean age, 48 years) without the condition. Brain MRI scans revealed white matter hyperintensities (WMH) – markers of damage to the brain’s white matter that occurs in the typical ageing process – in 33% of the participants with diabetes but only 7% of those without the condition. Participants with diabetes were also significantly slower, by about 20%, in cognitive tests assessing speed of information processing, independently of age or education.
Subanalysis of the diabetes group showed that those with greater volumes of WMH had lower cognitive scores than those with lower volumes. These associations remained even when adjusting for blood pressure and glycaemic control. Signs of neuropathy, such as numbness and tingling in the extremities, and smoking tripled the odds of a high WMH burden.
An accompanying editorial stated that these results were striking given the relatively young age of the participants, and they indicate that the known relationship between diabetes and cognitive decline is not confined to old age. While longitudinal studies are required to fully understand WMH development and its long-term effects on cognition, these findings suggest that clinicians should consider screening middle-aged people with type 1 diabetes for cognitive difficulties.
Caterina Rosano, the senior author of the study, said: “The severity of cognitive complications and cerebral small vessel disease – which can starve the brain of oxygen – is much more intense than we expected, but it can be measured in a clinical setting.
“Further study in younger patients is needed, but it stands to reason that early detection and intervention – such as controlling cardiometabolic factors and tighter glycaemic control, which help prevent microvascular complications – also could reduce or delay these cognitive complications.”
The study can be read in full here.
