Objective: To investigate the differences of cognitive function and brain volume between patients with type 2 diabetes mellitus (DM) and healthy controls.
Methods: Multi-dimensional neuropsychological tests were employed to evaluated cognitive function in 21 type 2 DM patients and 19 healthy controls, and voxel-based morphometry method was applied to measure volume of whole and regional gray matter in brain of these subjects.
Results: Compared to healthy controls [(7.3 +/- 1.4), (22.7 +/- 1.2), (9.5 +/- 2.5) respectively], significantly impaired performance of Auditory Verbal Learning Test (AVLT)-Delay Recall, [(5.7 +/- 1.8)] AVLT-Recognition [(20.8 +/- 2.6)] and Clock Drawing Test (CDT) [(8.0 +/- 1.1)] and extensive atrophy of gray matter (after corrected by total intracranial volume) were observed in type 2 DM patients (P < 0.05). In addition, whole gray matter/Total Intracranial Volume (TIV) was significantly negatively correlated with BMI (r = -0.352, P = 0.013). And negative correlations existed between whole gray matter vs HbA1c (r = -0.309, P = 0.026); the performance of AVLT-Delay Recall and AVLT-Recognition vs BMI (r = -0.398, P = 0.011; r = -0.4, P = 0.011)and HbA1c (r = -0.354, P = 0.025; r = -0.323, P = 0.042) and CDT vs HbA1c (r = -0.322, P = 0.043).
Conclusion: Multi-cognitive impairment was associated with the reduced volume of whole and regional gray matter in brain of type 2 DM patients, which indicated that "accelerated brain ageing" might present in type 2 DM patients.