@article {1005, title = {Abnormal regional cerebral blood flow in cognitively normal elderly subjects with hypertension.}, journal = {Stroke}, volume = {39}, year = {2008}, month = {2008 Feb}, pages = {349-54}, abstract = {

BACKGROUND AND PURPOSE: The purpose of this study was to examine regional cerebral blood flow (rCBF) in normal cognitive-performing subjects with hypertension (HTN) using continuous arterial spin-labeled MRI. The most common explanation for the effect of blood pressure on cognition is that HTN increases the risk of cerebrovascular disease, and it may increase the risk for Alzheimer disease possibly through small vessel disease, ischemia, oxidative stress, and inflammation. However, few studies to date have examined the rCBF of cognitively normal subjects with HTN in population-based cohorts, and none have used continuous arterial spin-labeled MRI. This is a noninvasive technique that does not require either injections or ionizing radiation and can measure absolute rCBF rates over the entire brain.

METHODS: rCBF was measured at 1.5 T using continuous arterial spin-labeled MRI in 41 cognitively normal subjects who were participating in the Cardiovascular Health Study Cognition Study. A deformable atrophy-corrected registration method was used to warp the rCBF maps to the standard colin27 brain space. Image and cluster-based statistical analyses were performed between subject groups.

RESULTS: Cognitively normal subjects with HTN (n=19) had decreased rCBF in the putamen, globus pallidus, bilaterally, and in the left hippocampus compared with normotensives (n=22). In addition, decreased rCBF was observed in the right and left anterior cingulate gyrus with extension to the subcallosal region, left posterior cingulate gyrus and medial precuneus, left lateral inferior and superior frontal, and inferior parietal, left orbitofrontal, and left superior temporal cortices.

CONCLUSIONS: rCBF is affected in normal subjects with HTN, not only in the subcortical regions, but also in limbic and paralimbic structures. We hypothesize that the HTN creates a vulnerability state for the development of neurodegenerative disorders, especially Alzheimer disease.

}, keywords = {Aged, Aged, 80 and over, Cerebral Cortex, Cerebrovascular Circulation, Cognition, Cognition Disorders, Female, Globus Pallidus, Gyrus Cinguli, Humans, Hypertension, Magnetic Resonance Imaging, Male, Putamen, Spin Labels}, issn = {1524-4628}, doi = {10.1161/STROKEAHA.107.495457}, author = {Dai, Weiying and Lopez, Oscar L and Carmichael, Owen T and Becker, James T and Kuller, Lewis H and Gach, H Michael} } @article {6815, title = {Association of Alzheimer{\textquoteright}s disease GWAS loci with MRI markers of brain aging.}, journal = {Neurobiol Aging}, volume = {36}, year = {2015}, month = {2015 Apr}, pages = {1765.e7-16}, abstract = {

Whether novel risk variants of Alzheimer{\textquoteright}s disease (AD) identified through genome-wide association studies also influence magnetic resonance imaging-based intermediate phenotypes of AD in the general population is unclear. We studied association of 24 AD risk loci with intracranial volume, total brain volume, hippocampal volume (HV), white matter hyperintensity burden, and brain infarcts in a meta-analysis of genetic association studies from large population-based samples (N = 8175-11,550). In single-SNP based tests, AD risk allele of APOE (rs2075650) was associated with smaller HV (p = 0.0054) and CD33 (rs3865444) with smaller intracranial volume (p = 0.0058). In gene-based tests, there was associations of HLA-DRB1 with total brain volume (p = 0.0006) and BIN1 with HV (p = 0.00089). A weighted AD genetic risk score was associated with smaller HV (beta {\textpm} SE = -0.047 {\textpm} 0.013, p = 0.00041), even after excluding the APOE locus (p = 0.029). However, only association of AD genetic risk score with HV, including APOE, was significant after multiple testing correction (including number of independent phenotypes tested). These results suggest that novel AD genetic risk variants may contribute to structural brain aging in nondemented older community persons.

}, keywords = {Aging, Alleles, Alzheimer Disease, Apolipoproteins E, Brain, Female, Genome-Wide Association Study, Hippocampus, Humans, Magnetic Resonance Imaging, Male, Organ Size, Polymorphism, Single Nucleotide, Risk, Sialic Acid Binding Ig-like Lectin 3}, issn = {1558-1497}, doi = {10.1016/j.neurobiolaging.2014.12.028}, author = {Chauhan, Ganesh and Adams, Hieab H H and Bis, Joshua C and Weinstein, Galit and Yu, Lei and T{\"o}glhofer, Anna Maria and Smith, Albert Vernon and van der Lee, Sven J and Gottesman, Rebecca F and Thomson, Russell and Wang, Jing and Yang, Qiong and Niessen, Wiro J and Lopez, Oscar L and Becker, James T and Phan, Thanh G and Beare, Richard J and Arfanakis, Konstantinos and Fleischman, Debra and Vernooij, Meike W and Mazoyer, Bernard and Schmidt, Helena and Srikanth, Velandai and Knopman, David S and Jack, Clifford R and Amouyel, Philippe and Hofman, Albert and DeCarli, Charles and Tzourio, Christophe and van Duijn, Cornelia M and Bennett, David A and Schmidt, Reinhold and Longstreth, William T and Mosley, Thomas H and Fornage, Myriam and Launer, Lenore J and Seshadri, Sudha and Ikram, M Arfan and Debette, Stephanie} } @article {7912, title = {Aortic Stiffness is Associated with Increased Risk of Incident Dementia in Older Adults.}, journal = {J Alzheimers Dis}, volume = {66}, year = {2018}, month = {2018}, pages = {297-306}, abstract = {

Cardiovascular disease risk factors, including age, hypertension, and diabetes, contribute to aortic stiffness and subclinical cardiovascular and brain disease, increasing dementia risk. Aortic stiffness, measured by carotid-femoral pulse wave velocity (cfPWV), reduces the buffering of pulsatile blood flow, exposing cerebral small arteries to microvascular damage. High cfPWV is related to white matter hyperintensities and brain amyloid deposition, and to cognitive decline, but it is unclear whether cfPWV independently predicts incident dementia. Therefore, we tested the hypothesis that cfPWV predicts incident dementia in older adults, independent of potential confounders. The Cardiovascular Health Study Cognition Study followed 532 non-demented older adults with annual cognitive exams from 1998-99 through 2013. CfPWV was measured on 356 (mean age = 78, 59\% women) between 1996-2000. Over 15 years, 212 (59.6\%) developed dementia (median time from cfPWV measurement = 4 years). In age and sex-adjusted Cox models, cfPWV was significantly associated with increased risk of dementia, but systolic blood pressure, mean arterial pressure and pulse pressure were not. CfPWV (transformed as - 1/cfPWV) remained significantly associated with dementia risk when further adjusted for education, race, APOEɛ4, diabetes, body mass index, mean arterial pressure, and anti-hypertensive medication (hazard ratio = 1.60, 95\% CI = 1.02, 2.51). Results were similar when further adjusted for baseline global cognition, subclinical brain measures, and coronary artery calcification. Finally, higher cfPWV was related to lower physical activity intensity and higher systolic blood pressure, heart rate, and waist circumference measured 5 years prior. An important unanswered question is whether interventions to slow arterial stiffening can reduce the risk of dementia.

}, issn = {1875-8908}, doi = {10.3233/JAD-180449}, author = {Cui, Chendi and Sekikawa, Akira and Kuller, Lewis H and Lopez, Oscar L and Newman, Anne B and Kuipers, Allison L and Mackey, Rachel H} } @article {8437, title = {Associations of body composition with incident dementia in older adults: Cardiovascular Health Study-Cognition Study.}, journal = {Alzheimers Dement}, year = {2020}, month = {2020 Aug 17}, abstract = {

INTRODUCTION: A body of literature reported associations between late-life general adiposity measures (eg, body mass index) and dementia. Little is known about the association of late-life body composition with dementia risk.

METHODS: We determined this association among cognitively normal participants from the Cardiovascular Health Study- Cognition Study. Body composition was assessed by dual-energy x-ray absorptiometry in 1994-1995. Dementia was ascertained at annual follow-up from 1998-1999 to 2013. Associations of body composition with incident dementia were assessed by the Fine-Gray model.

RESULT: Among 344 participants (mean age 78, 62.2\% women), body composition was significantly different between men and women, despite similar body mass indexes (BMIs). Increased dementia risk was significantly associated with lower lean mass in men and marginally with low appendicular lean mass in women.

DISCUSSION: Decreased lean mass was an indicator of increased dementia risk in older adults. Studies should test whether preventing lean mass loss in older adults reduces dementia risk.

}, issn = {1552-5279}, doi = {10.1002/alz.12125}, author = {Cui, Chendi and Mackey, Rachel H and Shaaban, C Elizabeth and Kuller, Lewis H and Lopez, Oscar L and Sekikawa, Akira} } @article {8988, title = {Association of low-frequency and rare coding variants with information processing speed.}, journal = {Transl Psychiatry}, volume = {11}, year = {2021}, month = {2021 12 04}, pages = {613}, abstract = {

Measures of information processing speed vary between individuals and decline with age. Studies of aging twins suggest heritability may be as high as 67\%. The Illumina HumanExome Bead Chip genotyping array was used to examine the association of rare coding variants with performance on the Digit-Symbol Substitution Test (DSST) in community-dwelling adults participating in the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) Consortium. DSST scores were available for 30,576 individuals of European ancestry from nine cohorts and for 5758 individuals of African ancestry from four cohorts who were older than 45 years and free of dementia and clinical stroke. Linear regression models adjusted for age and gender were used for analysis of single genetic variants, and the T5, T1, and T01 burden tests that aggregate the number of rare alleles by gene were also applied. Secondary analyses included further adjustment for education. Meta-analyses to combine cohort-specific results were carried out separately for each ancestry group. Variants in RNF19A reached the threshold for statistical significance (p = 2.01 {\texttimes} 10) using the T01 test in individuals of European descent. RNF19A belongs to the class of E3 ubiquitin ligases that confer substrate specificity when proteins are ubiquitinated and targeted for degradation through the 26S proteasome. Variants in SLC22A7 and OR51A7 were suggestively associated with DSST scores after adjustment for education for African-American participants and in the European cohorts, respectively. Further functional characterization of its substrates will be required to confirm the role of RNF19A in cognitive function.

}, keywords = {Adult, Aging, Cognition, Genome-Wide Association Study, Geroscience, Humans, Polymorphism, Single Nucleotide, Ubiquitin-Protein Ligases}, issn = {2158-3188}, doi = {10.1038/s41398-021-01736-6}, author = {Bressler, Jan and Davies, Gail and Smith, Albert V and Saba, Yasaman and Bis, Joshua C and Jian, Xueqiu and Hayward, Caroline and Yanek, Lisa and Smith, Jennifer A and Mirza, Saira S and Wang, Ruiqi and Adams, Hieab H H and Becker, Diane and Boerwinkle, Eric and Campbell, Archie and Cox, Simon R and Eiriksdottir, Gudny and Fawns-Ritchie, Chloe and Gottesman, Rebecca F and Grove, Megan L and Guo, Xiuqing and Hofer, Edith and Kardia, Sharon L R and Knol, Maria J and Koini, Marisa and Lopez, Oscar L and Marioni, Riccardo E and Nyquist, Paul and Pattie, Alison and Polasek, Ozren and Porteous, David J and Rudan, Igor and Satizabal, Claudia L and Schmidt, Helena and Schmidt, Reinhold and Sidney, Stephen and Simino, Jeannette and Smith, Blair H and Turner, Stephen T and van der Lee, Sven J and Ware, Erin B and Whitmer, Rachel A and Yaffe, Kristine and Yang, Qiong and Zhao, Wei and Gudnason, Vilmundur and Launer, Lenore J and Fitzpatrick, Annette L and Psaty, Bruce M and Fornage, Myriam and Arfan Ikram, M and van Duijn, Cornelia M and Seshadri, Sudha and Mosley, Thomas H and Deary, Ian J} } @article {8990, title = {Association of Serum Neurofilament Light Chain Concentration and MRI Findings in Older Adults: The Cardiovascular Health Study.}, journal = {Neurology}, volume = {98}, year = {2022}, month = {2022 Mar 01}, pages = {e903-e911}, abstract = {

BACKGROUND AND OBJECTIVES: Neurofilament light chain (NfL) in blood is a sensitive but nonspecific marker of brain injury. This study sought to evaluate associations between NfL concentration and MRI findings of vascular brain injury in older adults.

METHODS: A longitudinal cohort study included 2 cranial MRI scans performed about 5 years apart and assessed for white matter hyperintensities (WMH) and infarcts. About 1 year before their second MRI, 1,362 participants (median age 77 years, 61.4\% women) without a history of TIA or stroke had measurement of 4 biomarkers: NfL, total tau, glial fibrillary acidic protein (GFAP), and ubiquitin carboxyl-terminal hydrolase L1. Most (n = 1,279) also had the first MRI scan, and some (n = 633) had quantitative measurements of hippocampal and WMH. In primary analyses, we assessed associations of NfL with a 10-point white matter grade (WMG) and prevalent infarcts on second MRI and with worsening WMG and incident infarct comparing the 2 scans. A value <0.0125 (0.05/4) was considered significant for these analyses. We also assessed associations with hippocampal and WMH volume.

RESULTS: In fully adjusted models, log(NfL) concentration was associated with WMG (β = 0.27; = 2.3 {\texttimes} 10) and worsening WMG (relative risk [RR] 1.24; = 0.0022), but less strongly with prevalent brain infarcts (RR 1.18; = 0.013) and not with incident brain infarcts (RR 1.18; = 0.18). Associations were also present with WMH volume (β = 2,242.9, = 0.0036). For the other 3 biomarkers, the associations for log (GFAP) concentration with WMG and worsening WMG were significant.

DISCUSSION: Among older adults without a history of stroke, higher serum NfL concentration was associated with covert MRI findings of vascular brain injury, especially the burden of WMH and its worsening. Whether these results offer opportunities for the use of NfL as a noninvasive biomarker of WMH or to control vascular risk factors remains to be determined.

}, issn = {1526-632X}, doi = {10.1212/WNL.0000000000013229}, author = {Fohner, Alison E and Bartz, Traci M and Tracy, Russell P and Adams, Hieab H H and Bis, Joshua C and Djouss{\'e}, Luc and Satizabal, Claudia L and Lopez, Oscar L and Seshadri, Sudha and Mukamal, Kenneth J and Kuller, Lewis H and Psaty, Bruce M and Longstreth, W T} } @article {9163, title = {Associations of Pulmonary Function with MRI Brain Volumes: A Coordinated Multi-Study Analysis.}, journal = {J Alzheimers Dis}, year = {2022}, month = {2022 Oct 03}, abstract = {

BACKGROUND: Previous studies suggest poor pulmonary function is associated with increased burden of cerebral white matter hyperintensities and brain atrophy among elderly individuals, but the results are inconsistent.

OBJECTIVE: To study the cross-sectional associations of pulmonary function with structural brain variables.

METHODS: Data from six large community-based samples (N = 11,091) were analyzed. Spirometric measurements were standardized with respect to age, sex, height, and ethnicity using reference equations of the Global Lung Function Initiative. Associations of forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and their ratio FEV1/FVC with brain volume, gray matter volume, hippocampal volume, and volume of white matter hyperintensities were investigated using multivariable linear regressions for each study separately and then combined using random-effect meta-analyses.

RESULTS: FEV1 and FVC were positively associated with brain volume, gray matter volume, and hippocampal volume, and negatively associated with white matter hyperintensities volume after multiple testing correction, with little heterogeneity present between the studies. For instance, an increase of FVC by one unit was associated with 3.5 ml higher brain volume (95\% CI: [2.2, 4.9]). In contrast, results for FEV1/FVC were more heterogeneous across studies, with significant positive associations with brain volume, gray matter volume, and hippocampal volume, but not white matter hyperintensities volume. Associations of brain variables with both FEV1 and FVC were consistently stronger than with FEV1/FVC, specifically with brain volume and white matter hyperintensities volume.

CONCLUSION: In cross-sectional analyses, worse pulmonary function is associated with smaller brain volumes and higher white matter hyperintensities burden.

}, issn = {1875-8908}, doi = {10.3233/JAD-220667}, author = {Frenzel, Stefan and Bis, Josh C and Gudmundsson, Elias F and O{\textquoteright}Donnell, Adrienne and Simino, Jeannette and Yaqub, Amber and Bartz, Traci M and Brusselle, Guy G O and B{\"u}low, Robin and DeCarli, Charles S and Ewert, Ralf and Gharib, Sina A and Ghosh, Saptaparni and Gireud-Goss, Monica and Gottesman, Rebecca F and Ikram, M Arfan and Knopman, David S and Launer, Lenore J and London, Stephanie J and Longstreth, W T and Lopez, Oscar L and Melo van Lent, Debora and O{\textquoteright}Connor, George and Satizabal, Claudia L and Shrestha, Srishti and Sigurdsson, Sigurdur and Stubbe, Beate and Talluri, Rajesh and Vasan, Ramachandran S and Vernooij, Meike W and V{\"o}lzke, Henry and Wiggins, Kerri L and Yu, Bing and Beiser, Alexa S and Gudnason, Vilmundur and Mosley, Thomas and Psaty, Bruce M and Wolters, Frank J and Grabe, Hans J and Seshadri, Sudha} } @article {9438, title = {Association of a blood-based aging biomarker index with death and chronic disease: Cardiovascular Health Study.}, journal = {J Gerontol A Biol Sci Med Sci}, year = {2023}, month = {2023 Jul 19}, abstract = {

BACKGROUND: A goal of gerontology is to discover phenotypes that reflect biological aging distinct from disease pathogenesis. Biomarkers that are strongly associated with mortality could be used to define such a phenotype. However, the relation of such an index with multiple chronic conditions warrants further exploration.

METHODS: A Biomarker Index (BI) was constructed in the Cardiovascular Health Study (N=3197), with a mean age of 74 years. The BI incorporated circulating levels of new biomarkers, including insulin-like growth factor-1, interleukin-6, amino-terminal pro-B-type natriuretic peptide, cystatin-C, C-reactive protein, tumor necrosis factor-alpha soluble receptor 1, fasting insulin, and fasting glucose, and was built based on their relationships with mortality. Cox proportional hazards models predicting a composite of death and chronic disease involving cardiovascular disease, dementia, and cancer were calculated with 6 years of follow-up.

RESULTS: The hazard ratio (HR, 95\% CI) for the composite outcome of death or chronic disease per category of BI was 1.65 (1.52, 1.80) and 1.75 (1.58, 1.94) in women and men, respectively. The HR (95\% CI) per 5 years of age was 1.57 (1.48, 1.67) and 1.55 (1.44, 1.67) in women and men, respectively. Moreover, BI could attenuate the effect of age on the composite outcome by 16.7\% and 22.0\% in women and men, respectively.

CONCLUSIONS: BI was significantly and independently associated with a composite outcome of death and chronic disease, and attenuated the effect of age. The BI that is composed of plasma biomarkers may be a practical intermediate phenotype for interventions aiming to modify the course of aging.

}, issn = {1758-535X}, doi = {10.1093/gerona/glad172}, author = {Zhang, Xiao and Sanders, Jason L and Boudreau, Robert M and Arnold, Alice M and Justice, Jamie N and Espeland, Mark A and Kuchel, George A and Barzilai, Nir and Kuller, Lewis H and Lopez, Oscar L and Kritchevsky, Stephen B and Newman, Anne B} } @article {9737, title = {Associations between toxicity-weighted concentrations and dementia risk: Results from the Cardiovascular Health Cognition Study.}, journal = {Sci Total Environ}, volume = {945}, year = {2024}, month = {2024 Oct 01}, pages = {173706}, abstract = {

BACKGROUND: Air pollution is a modifiable risk factor for dementia. Yet, studies on specific sources of air pollution (i.e., toxic chemical emissions from industrial facilities) and dementia risk are scarce. We examined associations between toxicity-weighted concentrations of industrial pollution and dementia outcomes among a large, multi-site cohort of older adults.

METHODS: Participants (n~=~2770) were~>=~65~years old (Mean~=~75.3, SD~=~5.1~years) from the Cardiovascular Health Cognition Study (1992-1999). Toxicity-weighted concentrations were estimated using the Risk Screening Environmental Indicator (RSEI) model which incorporates total reported chemical emissions with toxicity, fate, and transport models. Estimates were aggregated to participants{\textquoteright} baseline census tract, averaged across 1988-1992, and log2-transformed. Dementia status was clinically adjudicated in 1998-1999 and categorized by subtype (Alzheimer{\textquoteright}s, vascular, mixed). We assessed whether RSEI-estimated toxicity-weighted concentrations were associated with 1) odds of prevalent dementia and 2) incident dementia risk by subtype.

RESULTS: After adjusting for individual and census-tract level covariates, a doubling in toxicity-weighted concentrations was associated with 9~\% higher odds of prevalent dementia (OR~=~1.09, 95~\% CI: 1.00, 1.19). In discrete-time survival models, each doubling in toxicity-weighted concentrations was associated with a 16~\% greater hazard of vascular dementia (HR~=~1.16, 95~\% CI: 1.01, 1.34) but was not significantly associated with all-cause, Alzheimer{\textquoteright}s disease, or mixed dementia (p{\textquoteright}s~>~0.05).

DISCUSSION: Living in regions with higher toxicity-weighted concentrations was associated with higher odds of prevalent dementia and a higher risk of incident vascular dementia in this large, community-based cohort of older adults. These findings support the need for additional studies to examine whether toxic chemical emissions from industrial and federal facilities may be a modifiable target for dementia prevention.

}, keywords = {Aged, Aged, 80 and over, Air Pollutants, Air Pollution, Dementia, Environmental Exposure, Female, Humans, Male, Risk Factors}, issn = {1879-1026}, doi = {10.1016/j.scitotenv.2024.173706}, author = {Crane, Breanna M and Moored, Kyle D and Donahue, Patrick T and Corrigan, Anne E and Curriero, Frank C and Shields, Timothy M and Desjardins, Michael R and Richards, Emily A and Rosso, Andrea L and Lovasi, Gina S and Odden, Michelle C and Lopez, Oscar L and Biggs, Mary Lou and Newman, Anne B and Andrews, Ryan M and Carlson, Michelle C} }