Low BDNF is associated with cognitive deficits in patients with type 2 diabetes.

Objective: Studies suggest that brain-derived neurotrophic factor (BDNF) plays an essential role in regulating memory-related neuroplasticity in the hippocampus. Type 2 diabetes (T2DM) is associated with impairment in many domains of cognitive function which may result from reduced BDNF; however, the correlation of BDNF with cognitive impairment in T2DM has not been investigated.

Methods: We compared 208 patients with T2DM to 212 normal controls on serum BDNF and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS).

Results: Serum BDNF levels were significantly decreased in T2DM patients compared to normal controls (p < 0.001). The total score and nearly all indexes (all p < 0.01) except for attention and visuospatial/constructional indexes (all p > 0.05) of RBANS were markedly lower in T2DM than controls. There was a positive relationship between serum BDNF and delayed memory in patients with T2DM.

Conclusions: Our results suggest that BDNF may play a role in the pathophysiology of cognitive deficits, especially delayed memory in T2DM.