INSERM U708 Neuroepidemiology, Bordeaux, Université Pierre et Marie Curie Paris 6, Paris, France.
Neurology. 2012 Mar 6;78(10):720-7. doi: 10.1212/WNL.0b013e318248e50f. Epub 2012 Feb 22.
The relation between inflammation and brain MRI findings in the elderly remains poorly known. We investigated the association of circulating interleukin-6 (IL-6) and C-reactive protein (CRP) levels with baseline and longitudinal white matter hyperintensities (WMH), silent brain infarction, and brain volumes in community-dwelling elderly free of dementia.
We included 1,841 participants aged 65 to 80 years from the Three City-Dijon cohort. Participants followed an MRI examination at baseline and after a 4-year follow-up (n = 1,316). IL-6 and CRP concentrations were measured at baseline from fasting blood samples. WMH were detected with an automatic imaging processing method and gray matter, hippocampal, white matter, and CSF volumes were estimated with voxel-based morphometry. Silent brain infarctions were assessed visually and defined as focal lesions of ≥3 mm in the absence of stroke. We used analysis of covariance and logistic regression to model the associations between inflammatory biomarkers and brain MRI findings adjusting for potential confounders.
In cross-sectional analyses, higher IL-6 levels were associated with higher WMH volumes (p < 0.01), lower gray matter (p = 0.001) and hippocampal (p = 0.01) volumes, and increasing CSF volumes (p = 0.002) in a dose-relationship pattern. Similar but weaker relations were observed for CRP. We observed no associations between baseline inflammatory biomarker levels and the evolution of MRI findings over 4 years.
IL-6, and, to a lesser degree, CRP levels were associated with WMH severity as well as global markers of brain atrophy. These results suggest that an inflammatory process may be involved in both age-associated brain alterations.
炎症与老年人脑部 MRI 结果之间的关系尚不清楚。我们研究了循环白细胞介素-6（IL-6）和 C 反应蛋白（CRP）水平与无痴呆的社区居住老年人基线和纵向脑白质高信号（WMH）、无症状性脑梗死和脑容量之间的关系。
我们纳入了来自三城市第戎队列的 1841 名 65 至 80 岁的参与者。参与者在基线和 4 年随访时进行 MRI 检查（n=1316）。IL-6 和 CRP 浓度在基线时从空腹血样中测量。WMH 采用自动成像处理方法检测，灰质、海马、白质和 CSF 体积采用基于体素的形态计量学估计。无症状性脑梗死通过视觉评估并定义为无中风情况下≥3mm 的局灶性病变。我们使用协方差分析和逻辑回归模型来调整潜在混杂因素后，研究炎症生物标志物与脑部 MRI 结果之间的关系。
在横断面分析中，较高的 IL-6 水平与较高的 WMH 体积（p<0.01）、较低的灰质（p=0.001）和海马（p=0.01）体积以及增加的 CSF 体积（p=0.002）呈剂量相关关系。CRP 也存在类似但较弱的关系。我们没有观察到基线炎症生物标志物水平与 4 年内 MRI 结果的演变之间的关联。
IL-6 以及在较小程度上 CRP 水平与 WMH 严重程度以及脑萎缩的全球标志物相关。这些结果表明，炎症过程可能与年龄相关的脑改变有关。
