Professor Esa Mervaala, M.D., Ph.D. Department of Clinical Neurophysiology, Kuopio University Hospital, POB 100, 70029 KYS, Finland, ORCID ID: 0000-0001-5682-5747, Mobile: +358-44-7113245, Email:
J Prev Alzheimers Dis. 2022;9(3):499-506. doi: 10.14283/jpad.2022.24.
Very recently, cognitively normal, middle-aged adults with severe obstructive sleep apnea (OSA) were shown to have regional cortical amyloid-β deposits. In the normal brain, amyloid tracer (e.g., [11C]-PiB) uptake is observed in white matter (WM) but not in cortical gray matter (GM), resulting in clear GM-WM contrast. There are no reports on possible changes in this contrast in severe OSA.
Evaluate changes in the global [11C]-PiB GM-WM contrast and study if factors reflecting clinical and imaging characteristics are associated with them.
Cross-sectional imaging study.
19 cognitively intact middle-aged (mean 44 years) patients with severe OSA (Apnea-Hypopnea Index >30/h), carefully selected to exclude any other possible factors that could alter brain health.
Detailed neuroimaging (amyloid PET, MRI). Signs of possible alterations in amyloid tracer GM-WM contrast and kinetics were studied with static and dynamic [11C]-PiB PET and WM structures with detailed 3.0T MRI.
Static [11C]-PiB PET uptake showed significantly decreased GM-WM contrast in 5 out of 19 patients. This was already clearly seen in visual evaluation and also detected quantitatively using retention indexes. Dynamic imaging revealed decreased contrast due to alterations in trace accumulation in the late phase of [11C]-PiB kinetics. Decreased GM-WM contrast in the late phase was global in nature. MRI revealed no corresponding alterations in WM structures. Importantly, decreased GM-WM contrast was associated with smoking (p = 0.007) and higher Apnea-Hypopnea Index (p = 0.001).
Severe OSA was associated with decreased GM-WM contrast in amyloid tracer uptake, with significant correlation with clinical parameters of smoking and AHI. The results support and further extend the current understanding of the deleterious effect of severe OSA on proper amyloid clearance, possibly reflecting dysfunction of the brain glymphatic system.
最近，研究发现患有严重阻塞性睡眠呼吸暂停（OSA）的认知正常中年患者存在区域性皮质淀粉样蛋白-β沉积。在正常大脑中，淀粉样蛋白示踪剂（例如[11C]-PiB）摄取仅见于白质（WM）而不存在于皮质灰质（GM）中，因此 WM 和 GM 之间具有明显的对比度。目前尚无关于严重 OSA 患者中这种对比变化的报道。
评估严重 OSA 患者中[11C]-PiB 皮质 GM-WM 对比度的变化，并研究反映临床和影像学特征的因素是否与这些变化相关。
横断面影像学研究。
19 名认知正常的中年（平均年龄 44 岁）严重 OSA 患者（呼吸暂停低通气指数>30/h），仔细选择排除任何可能改变大脑健康的其他因素。
详细的神经影像学（淀粉样蛋白 PET、MRI）。使用静态和动态[11C]-PiB PET 以及详细的 3.0T MRI 研究 WM 结构，研究淀粉样蛋白示踪剂 GM-WM 对比度和动力学的可能变化迹象。
静态[11C]-PiB PET 摄取显示 19 名患者中有 5 名患者的 GM-WM 对比度明显降低。这在视觉评估中已经很明显，并且使用保留指数也可以定量检测到。动态成像显示由于[11C]-PiB 动力学后期阶段示踪剂积聚的改变导致对比度降低。晚期 GM-WM 对比度的降低是全球性的。MRI 显示 WM 结构无相应改变。重要的是，GM-WM 对比度降低与吸烟（p=0.007）和较高的呼吸暂停低通气指数（p=0.001）相关。
严重 OSA 与淀粉样蛋白摄取的 GM-WM 对比度降低有关，与吸烟和 AHI 等临床参数具有显著相关性。这些结果支持并进一步扩展了严重 OSA 对正常淀粉样蛋白清除有害影响的现有认识，可能反映了脑糖质系统功能障碍。
Zotero 插件