Qiao Yujia, Wanigatunga Amal A, An Yang, Liu Fangyu, Spira Adam P, Davatzikos Christos, Tian Qu, Simonsick Eleanor M, Ferrucci Luigi, Resnick Susan M, Schrack Jennifer A
Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
Center on Aging and Health, Johns Hopkins University, Baltimore, MD, USA.
Sci Rep. 2022 Apr 19;12(1):6472. doi: 10.1038/s41598-022-10421-7.
Peak energy capacity of the whole person is associated with neurodegeneration. However, change in ability to utilize energy manifests as combination of declining peak energy capacity and rising energetic costs of mobility in mid-to-late life. We examined longitudinal associations between change in energy utilization and brain volumes. Cognitively normal participants from the Baltimore Longitudinal Study of Aging (N = 703, age = 70.4 ± 12.1 years, 54.1% women, 30% black) had concurrent data on brain volumes and energy utilization (defined as ratio of energetic cost of walking to peak energy capacity ("cost-to-capacity ratio") at ≥ 1 visit between 2008 and 2018. We performed linear mixed-effect models, adjusting for demographics, medical history and walking engagement. Average baseline cost-to-capacity ratio was 0.55 ± 0.16, with average annual increase of 0.04 ± 0.13 over 3.9 follow-up years. A 10% higher baseline cost-to-capacity ratio was associated with 2.00 cm (SE = 0.44) larger baseline ventricular volume (p < 0.001), and 0.10 cm (SE = 0.03) greater annual increase in ventricular volume (p = 0.004) after adjustment. Longitudinal change in cost-to-capacity ratio was not associated with brain volumes. These findings highlight, among cognitive-normal adults, poorer baseline energy utilization is associated with subsequent ventricular enlargement, an indirect measure of central brain atrophy. Future studies should explore whether early detection of worsening energy utilization may act as a marker of underlying brain atrophy.
人的峰值能量容量与神经退行性变有关。然而，能量利用能力的变化表现为中年后期峰值能量容量下降和活动能量成本上升的综合结果。我们研究了能量利用变化与脑容量之间的纵向关联。来自巴尔的摩纵向衰老研究的认知正常参与者（N = 703，年龄 = 70.4 ± 12.1岁，54.1%为女性，30%为黑人）在2008年至2018年期间至少有一次就诊时同时拥有脑容量和能量利用数据（定义为步行能量成本与峰值能量容量之比，即“成本与容量比”）。我们进行了线性混合效应模型分析，并对人口统计学、病史和步行参与情况进行了调整。平均基线成本与容量比为0.55 ± 0.16，在3.9年的随访期间平均每年增加0.04 ± 0.13。调整后，基线成本与容量比高出10%与基线脑室体积增大2.00 cm（标准误 = 0.44）相关（p < 0.001），且脑室体积每年增加幅度高出0.10 cm（标准误 = 0.03）（p = 0.004）。成本与容量比的纵向变化与脑容量无关。这些发现表明，在认知正常的成年人中，较差的基线能量利用与随后的脑室扩大有关，脑室扩大是脑中央萎缩的一种间接测量指标。未来的研究应探讨早期发现能量利用恶化是否可作为潜在脑萎缩的标志物。
