@article {6592, title = {Regular fish consumption and age-related brain gray matter loss.}, journal = {Am J Prev Med}, volume = {47}, year = {2014}, month = {2014 Oct}, pages = {444-51}, abstract = {

BACKGROUND: Brain health may be affected by modifiable lifestyle factors; consuming fish and antioxidative omega-3 fatty acids may reduce brain structural abnormality risk.

PURPOSE: To determine whether dietary fish consumption is related to brain structural integrity among cognitively normal elders.

METHODS: Data were analyzed from 260 cognitively normal individuals from the Cardiovascular Health Study with information on fish consumption from the National Cancer Institute Food Frequency Questionnaire and brain magnetic resonance imaging (MRI). The relationship between fish consumption data collected in 1989-1990 and brain structural MRI obtained in 1998-1999 was assessed using voxel-based morphometry in multiple regression analyses in 2012. Covariates were age, gender, race, education, white matter lesions, MRI-identified infarcts, waist-hip ratio, and physical activity as assessed by the number of city blocks walked in 1 week. Volumetric changes were further modeled with omega-3 fatty acid estimates to better understand the mechanistic link between fish consumption, brain health, and Alzheimer disease.

RESULTS: Weekly consumption of baked or broiled fish was positively associated with gray matter volumes in the hippocampus, precuneus, posterior cingulate, and orbital frontal cortex even after adjusting for covariates. These results did not change when including omega-3 fatty acid estimates in the analysis.

CONCLUSIONS: Dietary consumption of baked or broiled fish is related to larger gray matter volumes independent of omega-3 fatty acid content. These findings suggest that a confluence of lifestyle factors influence brain health, adding to the growing body of evidence that prevention strategies for late-life brain health need to begin decades earlier.

}, keywords = {Aged, Aged, 80 and over, Animals, Brain, Cross-Sectional Studies, Diet, Fatty Acids, Omega-3, Female, Fishes, Gray Matter, Humans, Life Style, Magnetic Resonance Imaging, Male, Regression Analysis, Surveys and Questionnaires}, issn = {1873-2607}, doi = {10.1016/j.amepre.2014.05.037}, author = {Raji, Cyrus A and Erickson, Kirk I and Lopez, Oscar L and Kuller, Lewis H and Gach, H Michael and Thompson, Paul M and Riverol, Mario and Becker, James T} } @article {6540, title = {Physical activity, body mass index, and brain atrophy in Alzheimer{\textquoteright}s disease.}, journal = {Neurobiol Aging}, volume = {36 Suppl 1}, year = {2015}, month = {2015 Jan}, pages = {S194-S202}, abstract = {

The purpose of this study was to use a novel imaging biomarker to assess associations between physical activity (PA), body mass index (BMI), and brain structure in normal aging, mild cognitive impairment, and Alzheimer{\textquoteright}s dementia. We studied 963 participants (mean age: 74.1 {\textpm} 4.4 years) from the multisite Cardiovascular Health Study including healthy controls (n~= 724), Alzheimer{\textquoteright}s dementia patients (n~=~104), and people with mild cognitive impairment (n~= 135). Volumetric brain images were processed using tensor-based morphometry to analyze regional brain volumes. We regressed the local brain tissue volume on reported PA and computed BMI, and performed conjunction analyses using both variables. Covariates included age, sex, and study site. PA was independently associated with greater whole brain and regional brain volumes and reduced ventricular dilation. People with higher BMI had lower whole brain and regional brain volumes. A PA-BMI conjunction analysis showed brain preservation with PA and volume loss with increased BMI in overlapping brain regions. In one of the largest voxel-based cross-sectional studies to date, PA and lower BMI may be beneficial to the brain across the spectrum of aging and neurodegeneration.

}, keywords = {Aged, Aged, 80 and over, Aging, Alzheimer Disease, Atrophy, Biomarkers, Body Mass Index, Brain, Cognitive Dysfunction, Cross-Sectional Studies, Diffusion Magnetic Resonance Imaging, Female, Humans, Magnetic Resonance Imaging, Male, Motor Activity, Neuroimaging}, issn = {1558-1497}, doi = {10.1016/j.neurobiolaging.2014.05.036}, author = {Boyle, Christina P and Raji, Cyrus A and Erickson, Kirk I and Lopez, Oscar L and Becker, James T and Gach, H Michael and Longstreth, W T and Teverovskiy, Leonid and Kuller, Lewis H and Carmichael, Owen T and Thompson, Paul M} } @article {7000, title = {Longitudinal Relationships between Caloric Expenditure and Gray Matter in the Cardiovascular Health Study.}, journal = {J Alzheimers Dis}, volume = {52}, year = {2016}, month = {2016}, pages = {719-29}, abstract = {

BACKGROUND: Physical activity (PA) can be neuroprotective and reduce the risk for Alzheimer{\textquoteright}s disease (AD). In assessing physical activity, caloric expenditure is a proxy marker reflecting the sum total of multiple physical activity types conducted by an individual.

OBJECTIVE: To assess caloric expenditure, as a proxy marker of PA, as a predictive measure of gray matter (GM) volumes in the normal and cognitively impaired elderly persons.

METHODS: All subjects in this study were recruited from the Institutional Review Board approved Cardiovascular Health Study (CHS), a multisite population-based longitudinal study in persons aged 65 and older. We analyzed a sub-sample of CHS participants 876 subjects (mean age 78.3, 57.5\% F, 42.5\% M) who had i) energy output assessed as kilocalories (kcal) per week using the standardized Minnesota Leisure-Time Activities questionnaire, ii) cognitive assessments for clinical classification of normal cognition, mild cognitive impairment (MCI), and AD, and iii) volumetric MR imaging of the brain. Voxel-based morphometry modeled the relationship between kcal/week and GM volumes while accounting for standard covariates including head size, age, sex, white matter hyperintensity lesions, MCI or AD status, and site. Multiple comparisons were controlled using a False Discovery Rate of 5 percent.

RESULTS: Higher energy output, from a variety of physical activity types, was associated with larger GM volumes in frontal, temporal, and parietal lobes, as well as hippocampus, thalamus, and basal ganglia. High levels of caloric expenditure moderated neurodegeneration-associated volume loss in the precuneus, posterior cingulate, and cerebellar vermis.

CONCLUSION: Increasing energy output from a variety of physical activities is related to larger gray matter volumes in the elderly, regardless of cognitive status.

}, issn = {1875-8908}, doi = {10.3233/JAD-160057}, author = {Raji, Cyrus A and Merrill, David A and Eyre, Harris and Mallam, Sravya and Torosyan, Nare and Erickson, Kirk I and Lopez, Oscar L and Becker, James T and Carmichael, Owen T and Gach, H Michael and Thompson, Paul M and Longstreth, W T and Kuller, Lewis H} } @article {7453, title = {Physical activity predicts reduced plasma β amyloid in the Cardiovascular Health Study.}, journal = {Ann Clin Transl Neurol}, volume = {4}, year = {2017}, month = {2017 May}, pages = {284-291}, abstract = {

OBJECTIVE: Higher levels of physical activity (PA) reduce the risk of cognitive impairment, but the underlying mechanisms are unclear. Using longitudinal data from the Cardiovascular Health Study, we examined whether PA predicted plasma Aβ levels and risk for cognitive decline 9-13 years later.

METHODS: Linear and logistic regressions (controlling for APOE status, age, gender, body mass index, cardiovascular disease, brain white matter lesions, and cystatin C levels) tested associations between PA, Aβ, and cognitive impairment in a sample of 149 cognitively normal older adults (mean age 83 years).

RESULTS: More PA at baseline predicted lower levels of Aβ 9-13 years later. Higher Aβ levels at year 9 predicted greater risk for cognitive impairment at year 13. Levels of Aβ at year 9 mediated the relationship between PA and cognitive impairment.

INTERPRETATION: Greater PA may reduce plasma levels of a neurotoxic peptide at an age when the risk for cognitive impairment is especially high.

}, issn = {2328-9503}, doi = {10.1002/acn3.397}, author = {Stillman, Chelsea M and Lopez, Oscar L and Becker, James T and Kuller, Lewis H and Mehta, Pankaj D and Tracy, Russell P and Erickson, Kirk I} } @article {8479, title = {Estrogen, brain structure, and cognition in postmenopausal women.}, journal = {Hum Brain Mapp}, year = {2020}, month = {2020 Sep 10}, abstract = {

Declining estrogen levels before, during, and after menopause can affect memory and risk for Alzheimer{\textquoteright}s disease. Undesirable side effects of hormone variations emphasize a role for hormone therapy (HT) where possible benefits include a delay in the onset of dementia-yet findings are inconsistent. Effects of HT may be mediated by estrogen receptors found throughout the brain. Effects may also depend on lifestyle factors, timing of use, and genetic risk. We studied the impact of self-reported HT use on brain volume in 562 elderly women (71-94 years) with mixed cognitive status while adjusting for aforementioned factors. Covariate-adjusted voxelwise linear regression analyses using a model with 16 predictors showed HT use as positively associated with regional brain volumes, regardless of cognitive status. Examinations of other factors related to menopause, oophorectomy and hysterectomy status independently yielded positive effects on brain volume when added to our model. One interaction term, HTxBMI, out of several examined, revealed significant negative association with overall brain volume, suggesting a greater reduction in brain volume than BMI alone. Our main findings relating HT to regional brain volume were as hypothesized, but some exploratory analyses were not in line with existing hypotheses. Studies suggest lower levels of estrogen resulting from oophorectomy and hysterectomy affect brain volume negatively, and the addition of HT modifies the relation between BMI and brain volume positively. Effects of HT may depend on the age range assessed, motivating studies with a wider age range as well as a randomized design.

}, issn = {1097-0193}, doi = {10.1002/hbm.25200}, author = {Boyle, Christina P and Raji, Cyrus A and Erickson, Kirk I and Lopez, Oscar L and Becker, James T and Gach, H Michael and Kuller, Lewis H and Longstreth, William and Carmichael, Owen T and Riedel, Brandalyn C and Thompson, Paul M} }