首发及复发抑郁症患者静息态fMRI研究:基于低频振幅和脑功能连接

Altered amplitude of low frequency-fluctuation and functional connectivity in first-episode and recurrent major depressive disorder:a resting-state fMRI study

目的:采用功能磁共振成像(fMRI)技术,基于低频振幅(ALFF)及静息态脑功能连接(rsFC),对比分析首发、复发抑郁症(MDD)患者和健康对照者之间脑自发活动及脑功能连接的差异,旨在探索首发及复发MDD的神经病理机制的差异。方法:前瞻性纳入2018年6月-2019年12月在本院就诊的47例首发MDD患者和35例复发MDD患者作为研究组。同期通过广告招募113例健康志愿者作为正常对照组。采集所有受试者的静息态fMRI数据,采用单因素协方差分析比较三组间各脑区ALFF值的差异,进而将有统计学差异的脑区作为种子点进行rsFC分析。结果:三组之间左侧颞上回和颞中回ALFF值的差异有统计学意义(P_(FWE)=0.007)。事后分析发现复发MDD组左侧颞上回和颞中回的ALFF值均高于首发MDD组和正常对照组,差异均有统计学意义(Ps<0.001,Bonferroni校正);而首发MDD组与对照组之间此指标值的差异无统计学意义(P>0.05,Bonferroni校正)。三组之间左侧颞上/中回-右侧楔前叶rsFC值的差异具有统计学意义(P_(FWE)=0.002)。事后分析发现首发和复发MDD组的rsFC值均高于对照组且差异有统计学意义(Ps<0.05,Bonferroni校正);复发组rsFC值高于首发组,但差异无统计学意义(P>0.05,Bonferroni校正)。结论:首发及复发MDD患者表现出左侧颞叶脑自发活动和左侧颞叶-楔前叶脑功能连接的异常及不同,这有助于区别首发及复发MDD的神经病理机制差异。

Objective:Functional magnetic resonance imaging(fMRI)technology and amplitude of low-frequency fluctuation(ALFF)and seed-based resting-state functional connectivity(rsFC)were used to detect differences in neural activity of the brain among patients with first-episode major depressive disorder(MDD),recurrent MDD and healthy controls,thus to explore the differences in the neural mechanisms between the first-episode MDD and recurrent MDD.Methods:Forty-seven first-episode MDD and 35 recurrent MDD patients who were treated in our hospital from June 2018 to December 2019 were selected as the research group prospectively.Meanwhile,one hundred and thirteen healthy controls were recruited through advertising.Resting-state fMRI data of all subjects were collected and ALFF values were calculated for each subject.Regions that showed significant differences among the three groups in ALFF were selected as seeds to calculate rsFC for each subject.Second-level analysis was completed using one-way analysis of covariance(ANCOVA).Results:Significant diffe-rence in ALFF among the three groups was found at the left superior/middle temporal gyrus(P_(FWE)=0.007).Post-hoc analysis showed that the recurrent patients showed significantly increased ALFF va-lue than that of the first-episode patients and healthy controls(Ps<0.001,Bonferroni correction).No significant difference was found between the first-episode patients and healthy controls(P>0.05,Bonferroni correction).Significant difference in rsFC among the three groups was found at the right precuneus(P_(FWE)=0.002).Post-hoc analysis showed that,both the first-episode MDD group and recurrent MDD group showed significantly increased rsFC values than those of the HC group(Ps<0.05,Bonferroni correction),and the recurrent patients exhibited higher rsFC values compared with the first-episode patients but the statistical value was not significant(P>0.05,Bonferroni correction).Conclusion:The first-episode patients and recurrent patients with MDD showed altered and distinct spontaneous brain activity fluctuations and functional connectivity,which has some significance for differentiating the differences in neuropathological mechanisms between the first-episode MDD and recurrent MDD.