Abstract MP057: Subclinical Cerebrovascular Disease is Associated with Worsening Gait and Balance in an Elderly Multi-Ethnic Population: The Northern Manhattan Study (NOMAS)

Abstract

Introduction: Age-related decline in gait and balance is a contributor to morbidity in the elderly. Subclinical cerebrovascular disease, seen on magnetic resonance imaging (MRI) as white matter hyperintensities (WMH) and silent brain infarcts (SBI), is associated with impaired mobility. Less is known about the association of WMH in specific brain regions and mobility impairment. We hypothesized that anterior WMH volume would be associated with lower scores on the Short Physical Performance Battery (SPPB), a well-validated mobility scale associated with falls and mortality in the elderly. Methods: Participants in the Northern Manhattan Study MRI cohort had the SPPB measured a median of 5 years after enrollment. The SPPB has three domains with a maximum total score of 12: gait speed, chair stands, standing balance. Volumetric distributions for WMH volume across 14 brain regions (brainstem, cerebellum, and bilateral frontal, occipital, temporal, and parietal lobes, and bilateral anterior and posterior periventricular white matter) were determined separately for each hemisphere by combining bimodal image intensity distribution and atlas based methods. Multi-variable linear regression was performed to examine the association between SBI and total and regional (frontal, parietal, occipital, temporal, anterior, posterior, and brainstem) head size-corrected WMH volumes, with the total SPPB score; models were adjusted for cardiovascular disease risk factors, osteo-arthritis, and grip strength. Results: Among 668 stroke-free participants with the SPPB available, mean age at the time of assessment was 74 ±9 years, 37% were male and 70% Hispanic; the mean SPPB score was 8.2 ± 2.9, interquartile range 7-10. Mean total WMHV was 0.55±0.75cc, mean anterior WMH volume 0.18±0.24cc, and 12% of participants had SBI. In multi-variable models, total WMHV was associated with a lower SPPB (beta = -0.3 per SD of logWMH, p=0.004), while SBI was not (beta= -0.12, p=0.7). For regional WMH volumes, only greater anterior periventricular WMHV was associated with SPPB (beta= -0.29 per SD, p=0.009). Conclusions: White matter hyperintensities, especially in the anterior cerebral regions, are associated with a lower SPPB. Prevention of subclinical cerebrovascular disease is a potential target to prevent physical aging in the elderly.