Wang Zuxing, Yuan Minlan, Xiao Jun, Chen Lili, Guo Xiaoyun, Dou Yikai, Jiang Fugui, Min Wenjiao, Zhou Bo
Sichuan Provincial Center for Mental Health, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, Chengdu, China; Key Laboratory of psychosomatic medicine, Chinese Academy of Medical Sciences, Chengdu, China.
1Sichuan Provincial Center for Mental Health, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Huaxi Brain Research Center, West China Hospital of Sichuan University, Chengdu, China Menta.
Pain Physician. 2022 Jan;25(1):1-13.
Many structural magnetic resonance imaging (MRI) studies have used voxel-based morphometry (VBM) to identify gray matter abnormalities in patients with chronic primary pain (CPP), but the findings have been inconsistent.
To identify (a) gray matter differences between CPP patients or female patients and healthy individuals and (b) the effects of symptom duration and pain scores on gray matter.
We conducted a meta-analysis.
VBM studies in PubMed, Cochrane Library, and Google Scholar, from November 2005 to June 2020, were thoroughly collected and carefully reviewed. Manual searches were performed using title and citation information. Gray matter VBM study comparing adult patients (18-65 years) with CPP to healthy controls was reviewed, and results, presented in Talairach or Montreal Neurological Institute coordinates, were included. The t value, peak coordinates, and basic clinical information of each study were reported in detail. Anisotropic effect-size signed differential mapping was used for voxel-based meta-analyses.
Patients with CPP had decreased gray matter in the left anterior cingulate (z value = 2.950, P < 0.001), right median cingulate (z value = 1.858, P = 0.001), and the insula bilaterally (left: z value = 2.441, P < 0.001; right: z value = 2.113, P < 0.001 ), and increased gray matter in the right striatum (z value = 1.194, P < 0.001). Subgroup meta-analysis showed female patients with CPP also had decreased gray matter in the left anterior cingulate gyrus (z value = 2.622, P < 0.001). Meta-regression analyses revealed that pain symptom duration was positively associated with a large right brain region (z value = 2.110, P < 0.001), a negative association between pain symptom duration and gray matter was found in the right anterior cingulate (z value = 1.969, P < 0.001) and right middle frontal gyrus (z value = 1.849, P < 0.001).
Due to the lack of data from male patients, we were unable to perform a male subgroup analysis; therefore, we cannot thoroughly explore the difference in CPP from the perspective of gender.
We identified gray matter changes in CPP patients and female patients, as well as a close relationship between CPP and mental disorders. With the chronicity of pain leads to changes in relevant brain regions, which makes treatment more challenging and may have synergistic effects with affective disorders. More prospective longitudinal structural MRI studies of CPP examining the associations between those variables and gray matter in a larger population should be conducted. Additional prospective longitudinal structural MRI studies of CPP with larger sample sizes to confirm the relationships between these variables and gray matter are needed as well as gender differences of CPP in brain structure and function.
许多结构磁共振成像（MRI）研究使用基于体素的形态计量学（VBM）来识别慢性原发性疼痛（CPP）患者的灰质异常，但研究结果并不一致。
确定（a）CPP患者或女性患者与健康个体之间的灰质差异，以及（b）症状持续时间和疼痛评分对灰质的影响。
我们进行了一项荟萃分析。
全面收集并仔细审查了2005年11月至2020年6月在PubMed、Cochrane图书馆和谷歌学术搜索中进行的VBM研究。使用标题和引用信息进行手动搜索。对比较成年（18 - 65岁）CPP患者与健康对照的灰质VBM研究进行了审查，并纳入了以Talairach或蒙特利尔神经学研究所坐标呈现的结果。详细报告了每项研究的t值、峰值坐标和基本临床信息。基于体素的荟萃分析使用了各向异性效应大小符号差异映射。
CPP患者左侧前扣带回（z值 = 2.950, P < 0.001）、右侧中央扣带回（z值 = 1.858, P = 0.001）以及双侧脑岛（左侧：z值 = 2.441, P < 0.001；右侧：z值 = 2.113, P < 0.001）灰质减少，右侧纹状体灰质增加（z值 = 1.194, P < 0.001）。亚组荟萃分析显示，女性CPP患者左侧前扣带回皮质灰质也减少（z值 = 2.622, P < 0.001）。荟萃回归分析显示，疼痛症状持续时间与大脑右侧的一个大区域呈正相关（z值 = 2.110, P < 0.001），在右侧前扣带回（z值 = 1.969, P < 0.001）和右侧额中回（z值 = 1.849, P < 0.001）发现疼痛症状持续时间与灰质呈负相关。
由于缺乏男性患者的数据，我们无法进行男性亚组分析；因此，我们无法从性别角度深入探讨CPP的差异。
我们确定了CPP患者和女性患者的灰质变化，以及CPP与精神障碍之间的密切关系。随着疼痛的慢性化导致相关脑区发生变化，这使得治疗更具挑战性，并且可能与情感障碍产生协同作用。应该进行更多关于CPP的前瞻性纵向结构MRI研究，以在更大人群中检查这些变量与灰质之间的关联。还需要更多样本量更大的CPP前瞻性纵向结构MRI研究，以确认这些变量与灰质之间的关系以及CPP在脑结构和功能方面的性别差异。
