Boots Elizabeth A, Schultz Stephanie A, Oh Jennifer M, Larson Jordan, Edwards Dorothy, Cook Dane, Koscik Rebecca L, Dowling Maritza N, Gallagher Catherine L, Carlsson Cynthia M, Rowley Howard A, Bendlin Barbara B, LaRue Asenath, Asthana Sanjay, Hermann Bruce P, Sager Mark A, Johnson Sterling C, Okonkwo Ozioma C
Geriatric Research Education and Clinical Center, William S. Middleton Memorial Veterans Hospital, Madison, WI, 53705 USA.
Department of Medicine and Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53792, USA.
Brain Imaging Behav. 2015 Sep;9(3):639-49. doi: 10.1007/s11682-014-9325-9.
Cardiorespiratory fitness (CRF) is an objective measure of habitual physical activity (PA), and has been linked to increased brain structure and cognition. The gold standard method for measuring CRF is graded exercise testing (GXT), but GXT is not feasible in many settings. The objective of this study was to examine whether a non-exercise estimate of CRF is related to gray matter (GM) volumes, white matter hyperintensities (WMH), cognition, objective and subjective memory function, and mood in a middle-aged cohort at risk for Alzheimer's disease (AD). Three hundred and fifteen cognitively healthy adults (mean age =58.58 years) enrolled in the Wisconsin Registry for Alzheimer's Prevention underwent structural MRI scanning, cognitive testing, anthropometric assessment, venipuncture for laboratory tests, and completed a self-reported PA questionnaire. A subset (n = 85) underwent maximal GXT. CRF was estimated using a previously validated equation incorporating sex, age, body-mass index, resting heart rate, and self-reported PA. Results indicated that the CRF estimate was significantly associated with GXT-derived peak oxygen consumption, validating its use as a non-exercise CRF measure in our sample. Support for this finding was seen in significant associations between the CRF estimate and several cardiovascular risk factors. Higher CRF was associated with greater GM volumes in several AD-relevant brain regions including the hippocampus, amygdala, precuneus, supramarginal gyrus, and rostral middle frontal gyrus. Increased CRF was also associated with lower WMH and better cognitive performance in Verbal Learning & Memory, Speed & Flexibility, and Visuospatial Ability. Lastly, CRF was negatively correlated with self- and informant-reported memory complaints, and depressive symptoms. Together, these findings suggest that habitual participation in physical activity may provide protection for brain structure and cognitive function, thereby decreasing future risk for AD.
心肺适能（CRF）是习惯性身体活动（PA）的一项客观指标，并且与大脑结构和认知能力的增强有关。测量CRF的金标准方法是分级运动试验（GXT），但GXT在许多情况下并不可行。本研究的目的是检验在有患阿尔茨海默病（AD）风险的中年队列中，CRF的非运动估计值是否与灰质（GM）体积、白质高信号（WMH）、认知、客观和主观记忆功能以及情绪相关。315名认知健康的成年人（平均年龄=58.58岁）参加了威斯康星州阿尔茨海默病预防登记处的研究，他们接受了结构磁共振成像扫描、认知测试、人体测量评估、静脉穿刺进行实验室检查，并完成了一份自我报告的身体活动问卷。其中一个子集（n = 85）进行了最大GXT测试。使用一个先前验证过的公式来估计CRF，该公式纳入了性别、年龄、体重指数、静息心率和自我报告的身体活动情况。结果表明，CRF估计值与GXT得出的峰值耗氧量显著相关，验证了其在我们样本中作为非运动CRF测量方法的有效性。在CRF估计值与几个心血管危险因素之间的显著关联中可以看到对这一发现的支持。较高的CRF与包括海马体、杏仁核、楔前叶、缘上回和额中回前部在内的几个与AD相关的脑区中更大的GM体积有关。CRF增加还与较低的WMH以及在言语学习与记忆、速度与灵活性和视觉空间能力方面更好的认知表现相关。最后，CRF与自我和他人报告的记忆问题以及抑郁症状呈负相关。总之，这些发现表明，习惯性参与体育活动可能为大脑结构和认知功能提供保护，从而降低未来患AD的风险。
