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Introduction: 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. Methods: 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. Results: 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, p = 0.001), anterior periventricular (beta = –0.4 per SD, p = 0.001), parietal (beta = –0.2 per SD, p = 0.02) and frontal (beta = –0.3 per SD, p = 0.002) WMHVs were associated with SPPB; other WMHV and SBI were not associated with the SPPB. Conclusions: 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. [ABSTRACT FROM AUTHOR]

Introduction: Gait speed is associated with multiple adverse outcomes of aging. We hypothesized that physical inactivity would be prospectively inversely associated with gait speed independently of white matter hyperintensity volume and silent brain infarcts on MRI. Methods: Participants in the Northern Manhattan Study MRI sub-study had physical activity assessed when they were enrolled into the study. A mean of 5 years after the MRI, participants had gait speed measured via a timed 5-meter walk test. Physical inactivity was defined as reporting no leisure-time physical activity. Multi-variable logistic and quantile regression was performed to examine the associations between physical inactivity and future gait speed adjusted for confounders. Results: Among 711 participants with MRI and gait speed measures (62% women, 71% Hispanic, mean age 74.1 ± 8.4), the mean gait speed was 1.02 ± 0.26 m/s. Physical inactivity was associated with a greater odds of gait speed in the lowest quartile (<0.85 m/s, adjusted OR 1.90, 95% CI 1.17-3.08), and in quantile regression with 0.06 m/s slower gait speed at the lowest 20 percentile (p = 0.005). Conclusions: Physical inactivity is associated with slower gait speed independently of osteoarthritis, grip strength, and subclinical ischemic brain injury. Modifying sedentary behavior poses a target for interventions aimed at reducing decline in mobility. [ABSTRACT FROM AUTHOR]

Background: Subclinical cerebrovascular disease has been associated with multiple adverse events related to aging, including stroke and dementia. The modifiable risk factors for subclinical cerebrovascular disease beyond hypertension have not been well characterized. Our objective was to examine the association between baseline, and changes over time, in lipid profile components and subclinical cerebrovascular disease on magnetic resonance imaging (MRI). Methods: Fasting plasma lipids were collected on participants in the Northern Manhattan Study, a prospective cohort study examining risk factors for cardiovascular disease in a multiethnic elderly urban-dwelling population. A subsample of the cohort underwent brain MRI between 2003 and 2008 (a median of 6.2 years, range = 0-14, after enrollment), when repeat fasting lipids were obtained. We used lipid profile components at the time of initial enrollment (n = 1,256 with lipids available) as categorical variables, as well as change in clinical categories over the two measures (n = 1,029). The main outcome measures were (1) total white matter hyperintensity volume (WMHV) using linear regression and (2) silent brain infarcts (SBI) using logistic regression. Results: None of the plasma lipid profile components at the time of enrollment were associated with WMHV. The association between baseline lipids and WMHV was, however, modified by apolipoprotein E (apoE) status (χ2 with 2 degrees of freedom, p = 0.03), such that among apoE4 carriers those with total cholesterol (TC) ≥200 mg/dl had a trend towards smaller WMHV than those with TC <200 mg/dl (difference in log WMHV -0.19, p = 0.07), while there was no difference among apoE3 carriers. When examining the association between WMHV and change in lipid profile components we noted an association with change in high-density lipoprotein cholesterol (HDL-C, >50 mg/dl for women, >40 mg/dl for men) and TC. A transition from low-risk HDL-C (>50 mg/dl for women, >40 mg/dl for men) at baseline to high-risk HDL-C at the time of MRI (vs. starting and remaining low risk) was associated with greater WMHV (difference in logWMHV 0.34, p value 0.03). We noted a similar association with transitioning to a TC ≥200 mg/dl at the time of MRI (difference in logWMHV 0.25, p value 0.006). There were no associations with baseline or change in lipid profile components with SBI. Conclusions: The association of plasma lipid profile components with greater WMHV may depend on apoE genotype and worsening HDL and TC risk levels over time. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]