INTRODUCTIONOlder adults with mild cognitive impairment (MCI) exhibit deficits in cerebrovascular reactivity (CVR), suggesting CVR is a biomarker for vascular contributions to MCI. This study examined if spontaneous CVR is associated with MCI and memory impairment.METHODSOne hundred sixty‐one older adults free of dementia or major neurological/psychiatric disorders were recruited. Participants underwent clinical interviews, cognitive testing, venipuncture for Alzheimer's disease (AD) biomarkers, and brain magnetic resonance imaging. Spontaneous CVR was quantified during 5 minutes of rest. Respiratory gases analyzed through nasal cannula to quantify end‐tidal carbon dioxide (ETCO2) levels were used to estimate CVR.RESULTSWhole brain CVR was negatively associated with age, but not MCI. Lower CVR in the parahippocampal gyrus (PHG) was found in participants with MCI and was linked to worse memory performance on memory tests. Results remained significant after adjusting for AD biomarkers and vascular risk factors.DISCUSSIONSpontaneous CVR deficits in the PHG are observed in older adults with MCI and memory impairment, suggesting medial temporal microvascular dysfunction is observed in cognitive decline.Highlights Aging is associated with decline in whole brain spontaneous cerebrovascular reactivity (CVR). Older adults with mild cognitive impairment exhibit deficits in spontaneous CVR in the parahippocampal gyrus (PHG). Memory impairment is correlated with reduced spontaneous CVR in the PHG.

中文翻译：

---

有和没有轻度认知障碍和记忆缺陷的老年人静息时的自发性脑血管反应


引言患有轻度认知障碍 （MCI） 的成年人表现出脑血管反应性 （CVR） 缺陷，表明 CVR 是血管对 MCI 贡献的生物标志物。本研究检查了自发性 CVR 是否与 MCI 和记忆障碍相关。方法招募了 161 名没有痴呆或主要神经/精神疾病的老年人。参与者接受了临床访谈、认知测试、阿尔茨海默病 （AD） 生物标志物的静脉穿刺和脑磁共振成像。在休息 5 分钟期间量化自发性 CVR。通过鼻插管分析呼吸气体以量化呼气末二氧化碳 （ETCO2） 水平用于估计 CVR。结果脑 CVR 与年龄呈负相关，但与 MCI 无关。在 MCI 参与者中发现海马旁回 （PHG） 的 CVR 较低，并且与记忆测试中较差的记忆表现有关。在调整 AD 生物标志物和血管危险因素后，结果仍然显著。讨论在患有 MCI 和记忆障碍的老年人中观察到 PHG 中的自发性 CVR 缺陷，表明在认知能力下降中观察到内侧颞叶微血管功能障碍。亮点 衰老与全脑自发性脑血管反应性 （CVR） 下降有关。患有轻度认知障碍的老年人表现出海马旁回 （PHG） 自发性 CVR 缺陷。记忆障碍与 PHG 中自发性 CVR 降低相关。