The Effect of Lifecourse Socioeconomic Position and Health on Trajectories of Cognitive Function in Older Adults.

Recent studies suggest that socioeconomic position (SEP) across the lifecourse may influence health, and more specifically cognitive health, through several pathways. However, few studies examining the effect of SEP on cognition have benefited from the use of longitudinal data and most have been confined to specific subpopulations of older adults or have been limited to restricted geographic areas. This overall goal of this dissertation research was to apply a lifecourse approach to the conceptualization and modeling of the social and economic determinants of cognitive performance, and attempt to further understand the relationship between disadvantage at different life stages and cognitive health in adulthood. This research uses data from the Health and Retirement Study (HRS), a nationally representative, prospective panel study of adults over 50 years of age, to: (1) estimate the effects of education and adulthood socioeconomic position on trajectories of cognitive change, (2) determine whether accumulation of socioeconomic disadvantage and social mobility from childhood to adulthood affects cognitive function, and (3) examine the association between body mass index and cognitive performance and decline in later life. These results support prior work documenting the lasting impact of education on cognition and suggest that measures of lifecourse SEP and adiposity may also be significant predictors of cognitive performance and change in older age.Ph.D.Epidemiological ScienceUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/58434/1/jfaul_1.pd

P2‐540: Polygenetic Risk For Alzheimer’S Disease And Dementia Status

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153242/1/alzjjalz2019062948.pd

Association studies of up to 1.2 million individuals yield new insights into the genetic etiology of tobacco and alcohol use.

Tobacco and alcohol use are leading causes of mortality that influence risk for many complex diseases and disorders1. They are heritable2,3 and etiologically related4,5 behaviors that have been resistant to gene discovery efforts6-11. In sample sizes up to 1.2 million individuals, we discovered 566 genetic variants in 406 loci associated with multiple stages of tobacco use (initiation, cessation, and heaviness) as well as alcohol use, with 150 loci evidencing pleiotropic association. Smoking phenotypes were positively genetically correlated with many health conditions, whereas alcohol use was negatively correlated with these conditions, such that increased genetic risk for alcohol use is associated with lower disease risk. We report evidence for the involvement of many systems in tobacco and alcohol use, including genes involved in nicotinic, dopaminergic, and glutamatergic neurotransmission. The results provide a solid starting point to evaluate the effects of these loci in model organisms and more precise substance use measures

Multi-ancestry study of blood lipid levels identifies four loci interacting with physical activity.

Many genetic loci affect circulating lipid levels, but it remains unknown whether lifestyle factors, such as physical activity, modify these genetic effects. To identify lipid loci interacting with physical activity, we performed genome-wide analyses of circulating HDL cholesterol, LDL cholesterol, and triglyceride levels in up to 120,979 individuals of European, African, Asian, Hispanic, and Brazilian ancestry, with follow-up of suggestive associations in an additional 131,012 individuals. We find four loci, in/near CLASP1, LHX1, SNTA1, and CNTNAP2, that are associated with circulating lipid levels through interaction with physical activity; higher levels of physical activity enhance the HDL cholesterol-increasing effects of the CLASP1, LHX1, and SNTA1 loci and attenuate the LDL cholesterol-increasing effect of the CNTNAP2 locus. The CLASP1, LHX1, and SNTA1 regions harbor genes linked to muscle function and lipid metabolism. Our results elucidate the role of physical activity interactions in the genetic contribution to blood lipid levels

P3‐558: Exposures Prior To Age 16 Are Associated With Dementia Status In The Health And Retirement Study

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/152762/1/alzjjalz2019063595.pd

Role of Extracellular Ionized Calcium in the In Vitro Assessment of GPIIb/IIIa Receptor Antagonists

Several preclinical studies have found a poor correlation between the ex vivo platelet inhibitory potency and the in vivo antithrombotic efficacy of GPIIb/IIIa receptor antagonists. The present study was designed to examine the differential in vitro potencies of c7E3, MK-383, DMP-728, and SM-20302 in inhibiting ex vivo platelet aggregation under normocalcemic and hypocalcemic conditions. Human blood was collected in either trisodium citrate (0.37%) or PPACK (20 µg/mL). Platelet aggregation assays were performed in platelet-rich plasma from citrate-anticoagulated blood (cPRP) and PPACK-anticoagulated blood (pPRP) using ADP (20 µM) and TRAP (10 µM) as agonists in the presence of c7E3, MK-383, DMP-728, or SM-20302. The concentration of ionized calcium in cPRP was 16–19 times lower than that in pPRP. The IC 50 of c7E3 for inhibiting ADP-induced platelet aggregation in cPRP (2.76 ± 0.11 µg/mL) was 1.6 times lower than that in pPRP (4.46 ± 0.48 µg/mL; P < 0.05). Similarly, the IC 50 for c7E3 for inhibiting TRAP-induced platelet aggregation in cPRP (4.52 ± 0.34 µg/mL) was 1.7 times lower than that in pPRP (7.69 ± 0.43 µg/mL; P < 0.05). MK-383, DMP-728, and SM-20302 also demonstrated 1.96-, 1.15-, and 1.43-fold lower IC 50 values, respectively, in cPRP as compared with pPRP. Chelation of ionized calcium in pPRP led to a progressive increase in platelet inhibition by all the antagonists. These results suggest that the observed in vitro inhibitory potency of a GPIIb/IIIa receptor antagonist is markedly enhanced when trisodium citrate is used as an anticoagulant to collect blood for ex vivo assay. These findings indicate that dosing regimens for GPIIb/IIIa receptor antagonists based on the platelet inhibition profile in citrate may provide misleading information with respect to their true in vivo antithrombotic efficacy.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48046/1/11239_2004_Article_202949.pd

O5‐08‐01: Trends In Racial And Ethnic Differences In Dementia Prevalence Rates And Disease Awareness

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153266/1/alzjjalz2019064876.pd

The complex genetics of gait speed:Genome-wide meta-analysis approach

Emerging evidence suggests that the basis for variation in late-life mobility is attributable, in part, to genetic factors, which may become increasingly important with age. Our objective was to systematically assess the contribution of genetic variation to gait speed in older individuals. We conducted a meta-analysis of gait speed GWASs in 31,478 older adults from 17 cohorts of the CHARGE consortium, and validated our results in 2,588 older adults from 4 independent studies. We followed our initial discoveries with network and eQTL analysis of candidate signals in tissues. The meta-analysis resulted in a list of 536 suggestive genome wide significant SNPs in or near 69 genes. Further interrogation with Pathway Analysis placed gait speed as a polygenic complex trait in five major networks. Subsequent eQTL analysis revealed several SNPs significantly associated with the expression of PRSS16, WDSUB1 and PTPRT, which in addition to the meta-analysis and pathway suggested that genetic effects on gait speed may occur through synaptic function and neuronal development pathways. No genome-wide significant signals for gait speed were identified from this moderately large sample of older adults, suggesting that more refined physical function phenotypes will be needed to identify the genetic basis of gait speed in aging

Racial and Ethnic Differences in Knowledge About One’s Dementia Status

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156478/1/jgs16442.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156478/3/jgs16442_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156478/2/jgs16442-sup-0001-supinfo.pd

GWAS of longevity in CHARGE consortium confirms APOE and FOXO3 candidacy.

To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked Files. This article is open access.The genetic contribution to longevity in humans has been estimated to range from 15% to 25%. Only two genes, APOE and FOXO3, have shown association with longevity in multiple independent studies.We conducted a meta-analysis of genome-wide association studies including 6,036 longevity cases, age ≥90 years, and 3,757 controls that died between ages 55 and 80 years. We additionally attempted to replicate earlier identified single nucleotide polymorphism (SNP) associations with longevity.In our meta-analysis, we found suggestive evidence for the association of SNPs near CADM2 (odds ratio [OR] = 0.81; p value = 9.66 × 10(-7)) and GRIK2 (odds ratio = 1.24; p value = 5.09 × 10(-8)) with longevity. When attempting to replicate findings earlier identified in genome-wide association studies, only the APOE locus consistently replicated. In an additional look-up of the candidate gene FOXO3, we found that an earlier identified variant shows a highly significant association with longevity when including published data with our meta-analysis (odds ratio = 1.17; p value = 1.85×10(-10)).We did not identify new genome-wide significant associations with longevity and did not replicate earlier findings except for APOE and FOXO3. Our inability to find new associations with survival to ages ≥90 years because longevity represents multiple complex traits with heterogeneous genetic underpinnings, or alternatively, that longevity may be regulated by rare variants that are not captured by standard genome-wide genotyping and imputation of common variants.Netherlands Organisation of Scientific Research NWO Investments 175.010.2005.011 911-03-012 Research Institute for Diseases in the Elderly 014-93-015 RIDE2 Netherlands Genomics Initiative (NGI)/Netherlands Organisation for Scientific Research (NWO) 050-060-810 Erasmus Medical Center Erasmus University, Rotterdam Netherlands Organization for the Health Research and Development (ZonMw) Research Institute for Diseases in the Elderly (RIDE) Ministry of Education, Culture and Science Ministry for Health, Welfare and Sports European Commission (DG XII) Municipality of Rotterdam National Institutes of Health National Institute on Aging (NIA) R01 AG005407 R01 AR35582 R01 AR35583 R01 AR35584 R01 AG005394 R01 AG027574 R01 AG027576 AG023629 R01AG29451 U01AG009740 RC2 AG036495 RC4 AG039029 P30AG10161 R01AG17917 R01AG15819 R01AG30146 U01-AG023755 U19-AG023122 NHLBI HHSN 268201200036C HHSN268200800007C N01HC55222 N01HC85079 N01HC85080 N01HC85081 N01HC85082 N01HC85083 N01HC 85086 HL080295 HL087652 HL105756 National Institute of Neurological Disorders and Stroke (NINDS) National Center for Advancing Translational Sciences, CTSI UL1TR000124 National Institute of Diabetes and Digestive and Kidney Disease Diabetes Research Center (DRC) DK063491 National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) National Center for Research Resources (NCRR) NIH Roadmap for Medical Research U01 AR45580 U01 AR45614 U01 AR45632 U01 AR45647 U01 AR45654 U01 AR45583 U01 AG18197 U01-AG027810 UL1 RR024140 NIAMS R01-AR051124 RC2ARO58973 National Heart, Lung and Blood Institute's Framingham Heart Study N01-HC-25195 Affymetrix, Inc N02-HL-6-4278 Robert Dawson Evans Endowment of the Department of Medicine at Boston University School of Medicine Boston Medical Center National Institute of Arthritis, Musculoskeletal and Skin Diseases NIA R01 AR/AG 41398 NIH N01-AG-12100 NIA Intramural Research Program Hjartavernd (the Icelandic Heart Association) Althingi (the Icelandic Parliament) Illinois Department of Public Health Translational Genomics Research Institute Italian Ministry of Health ICS110.1/RF97.71 U.S. National Institute on Aging 263 MD 9164 263 MD 821336 Intramural Research Program of the NIH, National Institute on Aging 1R01AG028321 1R01HL09257