Rosano Caterina, Brach Jennifer, Studenski Stephanie, Longstreth W T, Newman Anne B
Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA 15213, USA.
Neuroepidemiology. 2007;29(3-4):193-200. doi: 10.1159/000111582. Epub 2007 Nov 27.
Gait variability is an index of how much gait parameters, such as step length, change from one step to the next. Gait variability increases with age and in individuals affected by cortical and subcortical neurodegenerative conditions, and it is associated with falls and incident mobility disability. The brain anatomical correlates of gait variability have not been studied in high-functioning community-dwelling older adults.
Gait variability and brain MRIs were assessed in a cohort of 331 men and women (mean age = 78.3 years) free from stroke, dementia or Parkinson's disease. Gait variability was computed for spatial parameters (step length and step width) and for temporal parameters (stance time). Subclinical brain vascular abnormalities were measured on brain MRIs as infarcts and white matter hyperintensities.
Greater variability of step length was associated with greater prevalence of infarcts, including infarcts in the basal ganglia, and with greater white matter hyperintensities severity, independent of age, gender, cognitive function and cardiovascular disease. Weaker associations were found between the other variability measures and the MRI measures.
In this group of older adults free from neurodegenerative diseases, a greater variability of step length was associated with greater burden of subclinical brain vascular abnormalities as defined by MRI.
步态变异性是指步态参数(如步长)在一步到下一步之间变化程度的指标。步态变异性随年龄增长以及受皮质和皮质下神经退行性疾病影响的个体而增加,并且与跌倒和新发行动障碍相关。在功能良好的社区居住老年人中,尚未对步态变异性的脑解剖学相关性进行研究。
对331名无中风、痴呆或帕金森病的男性和女性(平均年龄 = 78.3岁)队列进行步态变异性和脑部MRI评估。计算空间参数(步长和步宽)和时间参数(站立时间)的步态变异性。在脑部MRI上测量亚临床脑血管异常,表现为梗死灶和白质高信号。
步长变异性越大,梗死灶(包括基底节梗死灶)的患病率越高,白质高信号严重程度越高,且不受年龄、性别、认知功能和心血管疾病的影响。在其他变异性测量指标与MRI测量指标之间发现较弱的相关性。
在这组无神经退行性疾病的老年人中,步长变异性越大,MRI定义的亚临床脑血管异常负担越重。