Objective To investigate the brain age differences between Alzheimer's disease(AD)and mild cognitive impairment(MCI)patients,and further explore the correlations between brain age gap(BAG)and clinical features.Methods The clinical data and radiologic findings of 132 probable AD and AD-derived MCI patients diagnosed at Beijing Tiantan Hospital,Capital Medical University from December 2018 to July 2021 were retrospectively analyzed.According to the diagnostic criteria for AD and MCI,the patients were assigned into AD and MCI groups.In addition,156 volunteers without neurological diseases and other severe diseases were recruited as the control group.The general data,Montreal cognitive assessment(MoCA)score,and mini-mental state examination(MMSE)score were compared among the three groups.The deep learning-based brain age prediction model was employed to calculate the BAGs of the three groups.Spearman correlation analysis was conducted to explore the correlations between BAG and clinical features.Results The 132 patients included 106 patients in the AD group and 26 patients in the MCI group.The MoCA and MMSE scores followed an ascending trend of AD group<MCI group<control group(all P<0.001).The predicted brain age and BAG in the AD group were higher than those in the MCI group(P=0.040,P=0.003)and control group(P=0.001,P<0.001).There was no significant difference in predicted brain age or BAG between MCI and control groups(P=0.352,P=0.224).BAG was negatively correlated with MoCA score(r=-0.341,P<0.001)and MMSE score(r=-0.324,P=0.001)in the AD group.Conclusion BAG can be used as an imaging biomarker to evaluate the degree of brain structural variation and the severity of brain injury in the patients with cognitive impairment.
目的 探讨阿尔茨海默病(AD)与轻度认知损害(MCI)患者的脑龄差异,并分析脑龄差(BAG)与临床特征之间的相关性。方法 回顾性分析2018年12月至2021年7月首都医科大学附属北京天坛医院临床诊断为很可能AD和AD源性MCI的132例患者的临床及影像资料。根据AD和MCI诊断标准分为AD组和MCI组;并纳入招募的排除神经系统疾病及其他系统严重疾病的156例志愿者作为对照组。比较3组患者的一般资料、蒙特利尔认知评估量表(MoCA)评分、简易精神状态检查量表(MMSE)评分的差异。采用深度学习脑龄预测模型计算3组的BAG,采用Spearman相关性分析探讨BAG与临床特征之间的相关性。结果 132例患者中,AD组106例,MCI组26例。AD组患者MoCA、MMSE评分均显著低于MCI和对照组(P均<0.001);MCI组患者MoCA、MMSE评分显著低于对照组(P均<0.001)。AD组患者预测脑龄、BAG显著高于MCI(P=0.040,P=0.003)和对照组(P=0.001,P<0.001);MCI组患者预测脑龄、BAG与对照组之间差异无统计学意义(P=0.352,P=0.224)。Spearman相关性分析结果显示,AD组BAG与MoCA评分(r=-0.341,P<0.001)、MMSE评分(r=-0.324,P=0.001)呈显著负相关。结论 BAG作为一种影像生物学标志物可以用于评价认知障碍患者的脑结构变异程度和脑损伤的严重程度。.
Keywords: Alzheimer’s disease; MRI; brain age; mild cognitive impairment.