Physical Activity and Cerebral Small Vein Integrity in Older Adults.

Identifying promoters of cerebral small vein integrity is important to counter vascular contributions to cognitive impairment and dementia. PURPOSE: In this preliminary investigation, the effects of a randomized 24-month physical activity (PA) intervention on changes in cerebral small vein integrity were compared to those of a health education (HE) control. METHODS: Cerebral small vein integrity was measured in 24 older adults (n = 8, PA; n = 16, HE) using ultra-high field MRI before and at the end of the 24-month intervention. Deep medullary veins were defined as straight or tortuous; percent change in straight length, tortuous length, and tortuosity ratio were computed. Microbleed count and white matter hyperintensities were also rated. RESULTS: Accelerometry-based values of PA increased by 17.2% in the PA group but declined by 28.0% in the HE group. The PA group, but not the HE group, had a significant increase in straight vein length from baseline to 24-month follow-up (P = 0.02 and P = 0.21, respectively); the between-group difference in percent change in straight length was significant (increase: median, 93.6%; interquartile range, 112.9 for PA; median, 28.4%; interquartile range, 90.6 for HE; P = 0.07). Between group differences in other markers were nonsignificant. CONCLUSIONS: Increasing PA in late-life may promote cerebral small vein integrity. This should be confirmed in larger studies.

The haptoglobin 1 allele correlates with white matter hyperintensities in middle-aged adults with type 1 diabetes.

Although the haptoglobin (Hp) 1-1 genotype is associated with a lower coronary artery disease (CAD) risk in diabetes, we recently reported an increased stroke incidence in type 1 diabetes with Hp 1-1. We, thus, evaluated differences in earlier brain vascular abnormality markers by Hp using neuroimaging. Neuroimaging was completed in 94 participants of the Pittsburgh Epidemiology of Diabetes Complications study with Hp genotyping available (mean age, 49; duration, 41 years). White matter hyperintensities (WMH) volume, lacunar infarcts, and gray matter atrophy were quantified. Sixteen percent were homozygous for Hp 1 and 43% for Hp 2. A significant trend toward increased WMH was observed with greater duration and the number of Hp 1 alleles. Associations were strongest for the interhemispheric connecting fibers of the corpus callosum. Allowing for duration, sex, waist-to-hip ratio, HbA1c, systolic blood pressure, and lipids in models with backward elimination, results were similar. No significant differences by Hp were noted for atrophy or lacunar infarcts. Consistent with its direct association with stroke, the Hp 1-1 genotype is associated with higher WMH in this population. Further, including mechanistic, studies on the role of the Hp genotype in cerebrovascular disease and the implications for worsening cognitive function are needed.