定量磁化率成像技术对抑郁症患者脑脊液铁沉积的纵向研究

A longitudinal study of iron deposition in cerebrospinal fluid of patients with depression based on quantitative susceptibility mapping

目的:基于MR定量磁化率成像技术分析抑郁症患者脑脊液(CSF)内铁沉积情况及其与临床发病程度和预后的关系。方法:前瞻性收集47例抑郁症患者(抑郁组)和21例年龄、性别相匹配的健康志愿者(对照组),在基线和标准化治疗6周后,应用汉密尔顿抑郁量表17项(HDS-17)对患者抑郁程度进行评估,根据评估结果将抑郁组分为缓解组和非缓解组,并采用定量磁化率成像(QSM)技术对受试者全脑行MR图像采集。以MNI-152脑模板行全脑标准化及CSF掩模的提取,获得CSF的磁化率值。采用两独立样本t检验对抑郁组和对照组CSF的磁化率值进行比较。采用Pearson相关分析对CSF磁化率值与抑郁严重程度及CSF内铁蛋白水平(经腰穿测量)进行相关性分析。采用Logistic回归分析筛选抑郁组患者治疗后转归的独立预测因子。结果:CSF的磁化率与CSF的铁蛋白水平呈显著正相关(r=0.904,P<0.05)。与对照组比较,抑郁组CSF的磁化率显著增高(t=-7.210,P<0.001)。相关分析结果显示治疗前抑郁组CSF磁化率与HDS-17评分呈正相关(r=0.644,P<0.001),标准化治疗6周后两者间亦呈显著正相关(缓解组:r=0.382,P<0.05;非缓解组:r=0.595,P<0.05)。多元Logistic回归分析显示基线CSF磁化率值、发病年龄、总病程是抑郁症患者治疗后转归的独立预测因子(OR=2.816,95%CI:1.031~7.691;OR=0.751,95%CI:0.514~0.994;OR=2.284,95%CI:1.007~5.180)。结论:抑郁症患者脑脊液内铁沉积水平与抑郁程度及治疗后转归密切相关,其或可作为抑郁疾病机制探索的重要切入点。

Objective:To investigate the iron deposition in cerebrospinal fluid(CSF)in patients with depression based on MR quantitative susceptibility mapping(QSM)and to analyze its relationship with clinical severity and prognosis.Methods:A prospective design was used in this study.47 hospitalized patients with depression(depression group)and 21 matched healthy controls(HC group)were collected.At baseline and 6 weeks after standardized treatment,Hamilton Depression Scale-17(HDS-17)was used to evaluate the severity of depression,and then the depression group was divided into remission group and non-remission group.QSM was used to obtain the whole brain MR images of each subject.The whole brain MR images were standardized and CSF mask was extracted using the MNI-152 brain template,subsequently the susceptibility of CSF was measured.The independent sample t-test was used to compare the CSF susceptibility of the two groups.The CSF susceptibility was correlated with the severity of depression and the ferritin level in CSF(measured by lumbar puncture)using Pearson correlation analysis.Logistic regression analysis was used to select out the independent predictors of post-treatment outcomes in the depression group.Results:CSF ferritin level was positively correlated withsusceptibility(r=0.904,P<0.05).Compared with the HC group,the CSF susceptibilitywas significantly higher in the depressed group(t=-7.210,P<0.001)and positively correlated with the HDS-17 score(r=0.644,P<0.001).After 6 weeks of treatment,there was still a significant positive correlation between the CSF susceptibility and HDS-17 score(remission group:r=0.382,P<0.05;non-remission group:r=0.595,P<0.05).Further multivariate logistic regression analysis showed that baseline CSF susceptibility(OR=2.816,95%CI:1.031~7.691),onset age(OR=0.751,95%CI:0.514~0.994)and total course of disease(OR=2.284,95%CI:1.007~5.180)were the independent predictors of post-treatment outcomes in patients with depression.Conclusion:CSF iron deposition is closelyassociated with the degree of depression and can be used as a biomarker for evaluation of depressive disorder and outcomes after treatment.