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Objective: Vascular risk factors (VRF) are known contributors to brain health in old age, with minority populations disproportionately impacted. The role of duration and severity of exposure to VRF remains unclear. We examined the association between cumulative exposures to VRF (cVRF) from young adulthood to midlife and midlife brain health, while addressing racial differences. Methods: 142 participants (39% black, 42% women) from the Coronary Artery Risk Development in Young Adults study with longitudinal VRF data over 30 years and a brain MRI at Y30 were included. Cumulative blood pressure (cBP), cholesterol, BMI, smoking, and glucose was calculated as the mean of two measures across two consecutive visits, multiplied by the number of years between visits from Y0 to Y30. Multivariate linear regression models including all VRF, demographics, and medications were used to assess the independent association of cVRF with brain MRI outcomes across races. Results: Higher cSBP was associated with lower total brain, gray matter, and hippocampal volumes in blacks, but not in whites (interaction p0.05). Conclusions: Exposure to higher BP across young adulthood is associated with midlife brain structure, possibly irrespective of race. Given higher level of cBP exposure in minorities, our observations should encourage clinicians to be aggressive in addressing hypertension in young adults, especially in young minority populations as a potential target to narrow disparities in brain health.

For people with disordered consciousness (DoC) after traumatic brain injury (TBI), relationships between treatment-induced changes in neural connectivity and neurobehavioral recovery have not been explored. To begin building a body of evidence regarding the unique contributions of treatments to changes in neural network connectivity relative to neurobehavioral recovery, we conducted a pilot study to identify relationships meriting additional examination in future research. To address this objective, we examined previously unpublished neural connectivity data derived from a randomized clinical trial (RCT). We leveraged these data because treatment efficacy, in the RCT, was based on a comparison of a placebo control with a specific intervention, the familiar auditory sensory training (FAST) intervention, consisting of autobiographical auditory-linguistic stimuli. We selected a subgroup of RCT participants with high-quality imaging data (FAST n = 4 and placebo n = 4) to examine treatment-related changes in brain network connectivity and how and if these changes relate to neurobehavioral recovery. To discover promising relationships among the FAST intervention, changes in neural connectivity, and neurobehavioral recovery, we examined 26 brain regions and 19 white matter tracts associated with default mode, salience, attention, and language networks, as well as three neurobehavioral measures. Of the relationships discovered, the systematic filtering process yielded evidence supporting further investigation of the relationship among the FAST intervention, connectivity of the left inferior longitudinal fasciculus, and auditory-language skills. Evidence also suggests that future mechanistic research should focus on examining the possibility that the FAST supports connectivity changes by facilitating redistribution of brain resources. For a patient population with limited treatment options, the reported findings suggest that a simple, yet targeted, passive sensory stimulation treatment may have altered functional and structural connectivity. If replicated in future research, then these findings provide the foundation for characterizing the unique contributions of the FAST intervention and could inform development of new treatment strategies. For persons with severely damaged brain networks, this report represents a first step toward advancing understanding of the unique contributions of treatments to changing brain network connectivity and how these changes relate to neurobehavioral recovery for persons with DoC after TBI. Clinical Trial Registry: NCT00557076, The Efficacy of Familiar Voice Stimulation During Coma Recovery (http://www.clinicaltrials.gov).