BACKGROUND Exposure to surgery with general anaesthesia (surgery/GA) is associated with cortical atrophy, but the aetiology remains unknown. Amyloid-β (Aβ) deposition is one of the hallmark pathological characteristics of Alzheimer's disease (AD). We examined brain Aβ burden in study participants exposed to surgery/GA. METHODS We performed a cross-sectional analysis of residents of Olmsted County, MN, USA, in the Mayo Clinic Study of Aging who were aged 70-97 yr and underwent measurement of (i) brain Aβ with Pittsburgh compound B positron emission tomography (PiB PET), (ii) brain glucose metabolism with 18-fluorodeoxyglucose (FDG) PET, and (iii) temporal cortical thickness with MRI. Separate analyses were performed with exposure to surgery/GA, defined as occurring after age 40 yr, and with exposure to surgery/GA, defined as occurring within 20 yr before neuroimaging. Imaging measurements were compared between participants who were exposed to surgery/GA vs not exposed. RESULTS Of the 2563 participants, 585 had PET scans. Regardless of the definition used to quantify exposure, no significant associations were detected between exposure and either global PiB PET or FDG PET. In contrast, exposure to surgery/GA was associated with an increased likelihood of abnormal cortical thinning: odds ratio (OR)=1.98 (95% confidence interval [CI]: 1.19-3.31); P=0.010 in those exposed after age 40 yr, and OR=1.64 (95% CI: 1.05-2.55); P=0.029 in those exposed in the prior 20 yr. CONCLUSIONS Exposure to surgery/GA is not associated with increases in cortical amyloid deposition. This finding suggests that the modest cortical thinning associated with surgery/GA is not related to AD pathology, but rather is caused by other processes.

中文翻译：

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成年期间接受全身麻醉手术与老年人大脑淀粉样蛋白沉积增加无关。


背景 接受全身麻醉手术（手术/GA）与皮质萎缩有关，但其病因仍不清楚。 β淀粉样蛋白（Aβ）沉积是阿尔茨海默病（AD）的标志性病理特征之一。我们检查了接受手术/GA 的研究参与者的大脑 Aβ 负荷。方法 我们对梅奥诊所老龄化研究中美国明尼苏达州奥姆斯特德县 70-97 岁的居民进行了横断面分析，并使用匹兹堡化合物 B 正电子发射断层扫描 (PiB) 测量 (i) 大脑 Aβ PET)，(ii) 18-氟脱氧葡萄糖 (FDG) PET 检测脑葡萄糖代谢，以及 (iii) MRI 颞叶皮质厚度。对暴露于手术/GA（定义为发生在 40 岁之后）和暴露于手术/GA（定义为发生在神经影像学检查前 20 年内）进行了单独分析。对接受手术/GA 的参与者与未接受手术/GA 的参与者之间的成像测量结果进行了比较。结果 2563 名参与者中，585 人接受了 PET 扫描。无论用于量化暴露的定义如何，均未检测到暴露与整体 PiB PET 或 FDG PET 之间存在显着关联。相反，接受手术/GA 与皮质异常变薄的可能性增加相关：比值比 (OR)=1.98（95% 置信区间 [CI]：1.19-3.31）； 40 岁后暴露者中 P=0.010，OR=1.64（95% CI：1.05-2.55）；对于过去 20 年暴露的患者，P=0.029。结论 接受手术/GA 与皮质淀粉样蛋白沉积的增加无关。这一发现表明，与手术/GA 相关的适度皮质变薄与 AD 病理无关，而是由其他过程引起的。