2型糖尿病患者认知功能及脑结构影像的观察

Study of cognitive function and brain volume in type 2 diabetic patients

目的探讨2型糖尿病（DM）患者与健康对照者认知功能水平与脑区体积的异同。方法应用多维度神经心理测试对比评估21例2型DM患者和19名健康对照者的神经认知功能；并采用基于体素的脑形态学（VBM）方法研究两组受试者全脑及局部脑区结构差异。结果2型DM组听觉词语记忆测试一延迟回忆项（AVIJT—delayrecall）[（5．7±1．8）分]、听觉词语记忆测试一再认回忆项（AVLT—recognition）[（20．8±2．6）分]和画钟测试（CDT）[（8．0±1．1）分]成绩均显著差于对照组[分别为（7．3±1．4）分，（22．7±1．2）分，（9．5±2．5）分]。2型DM组全脑灰质容积[（528±65）mm2]明显小于对照组[（614±80）mm2]，在全脑容积（TIV）校正后差异仍有统计学意义。2型DM患者双侧颞上回，左侧颞中回，双侧岛叶，双侧额中回，右侧额下回，左侧顶下小叶，双侧中央前回，双侧扣带后回，左侧扣带前回，双侧海马旁回及右侧楔前叶体积较对照组明显萎缩（P〈0．001）。2型DM患者全脑灰质容积/TIV与体重指数（BMI）呈负相关，全脑灰质容积与糖化血红蛋白（HbAlC）负相关。AVLT-delayrecall和AVLT—recognition与BMI和HbAlC均负相关，CDT与HbAlC呈负相关。结论2型DM患者认知水平降低且伴全脑灰质容积减少及局部脑萎缩，提示2型DM患者可能存在加速脑老化的因素，引起认知功能下降。

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 volum 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 HbA1 c （ 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 HbA1 c （ r = -0.354, P =0.025;r = -0.323, P =0.042） and CDT vs HbAlc （r = -0.322, P =0.043）. Conclusion Mutli-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.