Aerobic training increases hippocampal volume and protects cognitive function for type 2 diabetes patients with normal cognition.

Aim To evaluate the effects of aerobic training on hippocampal volume and cognitive function in type 2 diabetes patients with normal cognition. Materials and methods 100 patients with type 2 diabetes mellitus (T2DM) aged 60-75 years who met inclusion criteria were randomized into the aerobic training group (n=50) and control group (n=50). The aerobic training group received 1 year of aerobic training, while the control group maintained their lifestyle without additional exercise intervention. The primary outcomes were hippocampal volume measured by MRI and the scores of Mini-mental State Examination (MMSE) or Montreal Cognitive Assessment scale (MoCA) scores. Results A total of 82 participants completed the study (aerobic training group, n=40; control group, n=42). There was no significant difference between the two groups at baseline (P>0.05). After one year of moderate aerobic training, increases of total and right hippocampal volume in the aerobic training group were significantly higher than those in the control group (P=0.027, P=0.043, respectively). In the aerobic group, total hippocampal volume significantly increased after intervention compared with baseline (P=0.034). The between-group difference in the change of MMSE and MoCA scores was statistically significant (P=0.015, P=0.027, respectively). Logistic regression showed strong correlations between aerobic training and increase in total hippocampal volume(OR:1.091, [95%CI 0.969, 1.228], P=0.002), improvement of MMSE scores (OR:1.127, [95%CI 1.005, 1.263], P=0.041) or MoCA scores(OR:2.564,[95%CI 2.098.2.973], P=0.045). Conclusions One-year moderate aerobic training increased total and right hippocampal volume and protected cognitive function for T2DM patients with normal cognition. Early intervention focusing on cognition protection should be considered for T2DM patients in clinical settings.