Supplementary Material for: Regional Subclinical Cerebrovascular Disease Is Associated with Balance in an Elderly Multi-Ethnic Population

<b><i>Introduction:</i></b> White matter hyperintensity volume (WMHV) and subclinical brain infarcts (SBI) are associated with impaired mobility, but less is known about the association of WMHV in specific brain regions. We hypothesized that anterior WMHV would be associated with lower scores on the Short Physical Performance Battery (SPPB), a well-validated mobility scale. <b><i>Methods:</i></b> The SPPB was measured a median of 5 years after enrollment into the Northern Manhattan MRI sub study. Volumetric distributions for WMHV in 14 brain regions as a proportion of total cranial volume were determined. Multi-variable linear regression was performed to examine the association of SBI and regional log-WMHV with the SPPB score. <b><i>Results:</i></b> Among 668 participants with SPPB measurements (mean 74 ± 9 years, 37% male and 70% Hispanic), the mean SPPB score was 8.2 ± 2.9. Total (beta = –0.3 per SD, <i>p</i> = 0.001), anterior periventricular (beta = –0.4 per SD, <i>p</i> = 0.001), parietal (beta = –0.2 per SD, <i>p</i> = 0.02) and frontal (beta = –0.3 per SD, <i>p</i> = 0.002) WMHVs were associated with SPPB; other WMHV and SBI were not associated with the SPPB. <b><i>Conclusions:</i></b> WMHV, especially in the anterior ­cerebral regions, is associated with a lower SPPB. Prevention of subclinical cerebrovascular disease is a potential target to prevent physical decline in the elderly.

引言：脑白质高信号体积（White matter hyperintensity volume, WMHV）与亚临床脑梗死（subclinical brain infarcts, SBI）均与运动功能受损相关，但目前针对特定脑区脑白质高信号体积的关联研究尚少。本研究假设，前部脑白质高信号体积与简短体能表现量表（Short Physical Performance Battery, SPPB）得分更低相关，而该量表是一项经过充分验证的运动功能评估工具。
方法：本研究针对北曼哈顿MRI亚队列的入组参与者，于入组后中位5年时测量其SPPB得分。研究人员测定了14个脑区内脑白质高信号体积占颅内总容积的比例分布，并采用多变量线性回归分析，探讨亚临床脑梗死及各脑区对数转换后脑白质高信号体积与SPPB得分的关联。
结果：本研究共纳入668名完成SPPB评分的参与者，其平均年龄为74±9岁，男性占比37%，西班牙裔占比70%，参与者的平均SPPB得分为8.2±2.9。分析显示，总脑白质高信号体积（回归系数β=-0.3/标准差，p=0.001）、前部脑室周围脑白质高信号体积（β=-0.4/标准差，p=0.001）、顶叶脑白质高信号体积（β=-0.2/标准差，p=0.02）及额叶脑白质高信号体积（β=-0.3/标准差，p=0.002）均与SPPB得分显著相关；其余脑区脑白质高信号体积及亚临床脑梗死则与SPPB得分无显著关联。
结论：脑白质高信号体积，尤其是前部脑区的脑白质高信号体积，与更低的SPPB得分相关。预防亚临床脑血管疾病或可成为延缓老年群体运动功能衰退的潜在干预靶点。