BACKGROUND Preclinical studies suggest that exposure to general anaesthesia (GA) could cause neurodegeneration consistent with Alzheimer's disease (AD) pathology. Brain magnetic resonance imaging (MRI) is useful to study structural brain changes. We tested the hypothesis that exposure to surgery with GA (surgery/GA) is associated with greater cortical thinning and increased frequency of white matter lesions. METHODS This is a cross-sectional analysis of 70-91-yr-old participants enrolled in the Mayo Clinic Study of Aging who had baseline MRI. The thickness of selected cortical regions, the volume of white matter hyperintensities, and the frequency of cortical infarctions were compared in participants who were and were not exposed to surgery/GA within 20 yr before the first MRI obtained after enrolment. RESULTS Of 1410 participants with MRI scans, 932 were exposed to surgery/GA before scanning. In adjusted analyses, cortical thickness in regions vulnerable to AD was significantly less in those exposed to surgery/GA in the prior 20 yr (difference -0.023 mm, [95% confidence interval (CI) -0.041 to -0.005], P=0.014). Those with surgery in the prior 20 yr were more likely to have 'abnormal thickness' compared with those without surgery (odds ratio=1.45, [95% CI 1.10-1.90], P=0.009). Exposure was not associated with white matter hyperintensities or the presence of brain infarcts. CONCLUSIONS This study suggests that exposure of older adults to surgical anaesthesia is associated with thinning in cortical regions implicated in AD. The pathogenesis and mechanisms driving these neurodegenerative changes, and the potential clinical significance of these findings, require further study.

中文翻译：

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老年人接受全身麻醉手术和脑磁共振成像变化。


背景临床前研究表明，全身麻醉（GA）可能导致与阿尔茨海默病（AD）病理学一致的神经变性。脑磁共振成像 (MRI) 可用于研究大脑结构变化。我们测试了这样的假设：接受 GA 手术（手术/GA）与皮质变薄和白质病变频率增加相关。方法 这是对参加 Mayo Clinic 衰老研究并进行基线 MRI 的 70-91 岁参与者进行的横断面分析。在入组后获得第一次 MRI 之前的 20 年内，对接受过手术/GA 和未接受过手术/GA 的参与者的选定皮质区域的厚度、白质高信号的体积和皮质梗塞的频率进行比较。结果 在 1410 名接受 MRI 扫描的参与者中，932 名在扫描前接受了手术/GA。在调整后的分析中，在过去 20 年接受过手术/GA 的患者中，易患 AD 的区域的皮质厚度显着减少（差异 -0.023 毫米，[95% 置信区间 (CI) -0.041 至 -0.005]，P=0.014 ）。与未接受手术的患者相比，过去 20 年接受过手术的患者更有可能出现“厚度异常”（比值比=1.45，[95% CI 1.10-1.90]，P=0.009）。暴露与白质高信号或脑梗塞的存在无关。结论 这项研究表明，老年人接受手术麻醉与 AD 相关的皮质区域变薄有关。驱动这些神经退行性变化的发病机制和机制，以及这些发现的潜在临床意义，需要进一步研究。