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

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. We compared 208 patients with T2DM to 212 normal controls on serum BDNF and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). 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. Our results suggest that BDNF may play a role in the pathophysiology of cognitive deficits, especially delayed memory in T2DM.