基于MRI的衰老过程中下丘脑及其亚区体积改变与认知功能下降的相关性研究

MRI-based correlation between volume changes in hypothalamus and its subregions and cognitive decline during aging

目的:研究基于MRI自动分割的下丘脑亚区体积和认知功能在成年人生命各个阶段的变化以及两者之间的相关性。方法:选取达拉斯寿命脑科学研究(Dallas Lifespan Brain Study,DLBS)公开数据库提供的314名年龄在20~89岁的健康受试者的结构磁共振成像(structural magnetic resonance imaging,sMRI)图像,并将受试者分为4组:青年组(20~35岁)、中早组(36~50岁)、中老组(51~65岁)和老年组(66~89岁)。使用Freesurfer软件处理sMRI图像得到下丘脑左右侧的前上部、前下部、中上部、中下部以及后部的体积。采用协方差分析比较4组间下丘脑亚区体积的差异,并使用Bonferroni校正进行4组间的多重比较。使用Pearson相关性系数分析下丘脑亚区体积和简易精神状态检查(mini mental state examination,MMSE)、数字比较(digit comparison,DC)测试、数字符号(digit symbol,DS)测试、霍普金斯词语学习测验(Hopkins verbal learning test,HVLT)评分的相关性。结果:除右前下部外,其余下丘脑亚区体积均随着年龄的增长而显著下降(P<0.05)。除右前下部外,其余下丘脑亚区体积均与MMSE评分呈正相关(P<0.05);DC测试评分与所有下丘脑亚区体积呈正相关(P<0.05);DS测试评分与除下丘脑双侧前下部外的下丘脑亚区体积呈正相关(P<0.05);HVLT即时记忆评分与下丘脑双侧前上部、中上部、后部体积呈正相关(P<0.05);HVLT延迟记忆评分与下丘脑双侧前上部、左侧中上部体积呈正相关(P<0.05);HVLT延迟再认评分与下丘脑所有亚区均无相关性(P>0.05);下丘脑的双侧总体积与MMSE、DC测试、DS测试和HVLT即时记忆评分呈正相关(P<0.05)。结论:在成年人的衰老过程中,部分下丘脑亚区体积变化与年龄相关的记忆衰退有关,并且这些区域的体积变化可用于评估整个成年阶段记忆力下降的风险。

Objective To study the changes of volume and cognitive function in hypothalamic subregions based on automated MRI segmentation at various stages of adult life and the correlation between them.Methods Totally 314 healthy subjects aged 20-89 years old were selected from the public database of Dallas Lifespan Brain Study(DLBS),and then divided into a youth group(20-35 years old),an early-middle age group(36-50 years old),a late-middle age group(51-65 years old)and an elderly age group(66-89 years old).The structural magnetic resonance imaging(sMRI)images of the 314 subjects were treated with Freesurfer software to determine the volumes of the anterosuperior,anterior-inferior,middle-superior,middle-inferior and posterior subregions of the right and left sides of the hypothalamus.Differences in hypothalamic subregion volumes between the 4 groups were compared using analysis of covariance,and multiple comparisons between the 4 groups were performed using Bonferroni correction.Pearson's correlation coefficients were used to analyze the correlations of the hypothalamic subregion volumes with the scores of mini mental state examination(MMSE),digit comparison(DC)test,digit symbol(DS)test,and Hopkins verbal learning test(HVLT).Results The volumes of all the hypothalamic subregions except the right anterior inferior part decreased significantly with age(P<0.05).All the hypothalamic subregions except the right anterior inferior part had the volumes correlated with MMSE scores positively(P<0.05);the DC test scores were correlated positively with all the hypothalamic subregion volumes(P<0.05);the DS test scores were correlated positively with the volumes of the hypothalamic subregions except the bilateral anterior-inferior part(P<0.05);the scores of HVLT immediate memory test were positively correlated with the anterior-superior,middle-superior and posterior subregion volumes of the right and left sides of the hypothalamus(P<0.05);the scores of HVLT delayed memory test were correlated positively with the volumes of the bilateral anterior-superior and left-middle-superior subregions(P<0.05);the scores of HVLT delayed recognition test did not correlate with all the hypothalamic subregions(P>0.05);the volumes of the bilateral hypothalamus were positively correlated with the scores of MMSE,DC test,DS test and HVLT immediate memory test(P<0.05).Conclusion Volume changes in some hypothalamic subregions are associated with age-related memory decline during adult aging,which can be used to assess the risk of memory loss throughout adulthood.