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Most transcriptome-wide association studies (TWASs) so far focus on European ancestry and lack diversity. To overcome this limitation, we aggregated genome-wide association study (GWAS) summary statistics, whole-genome sequences and expression quantitative trait locus (eQTL) data from diverse ancestries. We developed a new approach, TESLA (multi-ancestry integrative study using an optimal linear combination of association statistics), to integrate an eQTL dataset with a multi-ancestry GWAS. By exploiting shared phenotypic effects between ancestries and accommodating potential effect heterogeneities, TESLA improves power over other TWAS methods. When applied to tobacco use phenotypes, TESLA identified 273 new genes, up to 55% more compared with alternative TWAS methods. These hits and subsequent fine mapping using TESLA point to target genes with biological relevance. In silico drug-repurposing analyses highlight several drugs with known efficacy, including dextromethorphan and galantamine, and new drugs such as muscle relaxants that may be repurposed for treating nicotine addiction.

Biomarkers developed from DNA methylation (DNAm) data are of growing interest as predictors of health outcomes and mortality in older populations. However, it is unknown how epigenetic aging fits within the context of known socioeconomic and behavioral associations with aging-related health outcomes in a large, population-based, and diverse sample. This study uses data from a representative, panel study of US older adults to examine the relationship between DNAm-based age acceleration measures in the prediction of cross-sectional and longitudinal health outcomes and mortality. We examine whether recent improvements to these scores, using principal component (PC)-based measures designed to remove some of the technical noise and unreliability in measurement, improve the predictive capability of these measures. We also examine how well DNAm-based measures perform against well-known predictors of health outcomes such as demographics, SES, and health behaviors. In our sample, age acceleration calculated using “second and third generation clocks,” PhenoAge, GrimAge, and DunedinPACE, is consistently a significant predictor of health outcomes including cross-sectional cognitive dysfunction, functional limitations and chronic conditions assessed 2 y after DNAm measurement, and 4-y mortality. PC-based epigenetic age acceleration measures do not significantly change the relationship of DNAm-based age acceleration measures to health outcomes or mortality compared to earlier versions of these measures. While the usefulness of DNAm-based age acceleration as a predictor of later life health outcomes is quite clear, other factors such as demographics, SES, mental health, and health behaviors remain equally, if not more robust, predictors of later life outcomes.

Background: Genetic variants within nearly 1000 loci are known to contribute to modulation of blood lipid levels. However, the biological pathways underlying these associations are frequently unknown, limiting understanding of these findings and hindering downstream translational efforts such as drug target discovery. Results: To expand our understanding of the underlying biological pathways and mechanisms controlling blood lipid levels, we leverage a large multi-ancestry metaanalysis (N = 1,654,960) of blood lipids to prioritize putative causal genes for 2286 lipid associations using six gene prediction approaches. Using phenome-wide association (PheWAS) scans, we identify relationships of genetically predicted lipid levels to other diseases and conditions. We confirm known pleiotropic associations with cardiovascular phenotypes and determine novel associations, notably with cholelithiasis risk. We perform sex-stratified GWAS meta-analysis of lipid levels and show that 3–5% of autosomal lipid-associated loci demonstrate sex-biased effects. Finally, we report 21 novel lipid loci identified on the X chromosome. Many of the sex-biased autosomal and X chromosome lipid loci show pleiotropic associations with sex hormones, emphasizing the role of hormone regulation in lipid metabolism. Conclusions: Taken together, our findings provide insights into the biological mechanisms through which associated variants lead to altered lipid levels and potentially cardiovascular disease risk., United States Department of Health & Human Services National Institutes of Health (NIH) - USA NIH National Heart Lung & Blood Institute (NHLBI) R01HL127564 R01HL142711, Wellcome Trust 201543/B/16/Z 202802/Z/16/Z, European Commission HEALTH-F2-2013-601456 608765 786833, TriPartite Immunometabolism Consortium [TrIC]-Novo Nordisk Foundation NNF15CC0018486, American Diabetes Association 1-19-ICTS-068, Academy of Finland 312062 Finnish Foundation for Cardiovascular Research, Sigrid Juselius Foundation, Finnish innovation fund Sitra (EW) Finska Lakaresallskapet, American Heart Association 15POST24470131 17POST33650016, University of Bristol NIHR Biomedical Research Centre BRC-1215-2001, MRC & WT 217065/Z/19/Z, UK Research & Innovation (UKRI), Medical Research Council UK (MRC) MC_UU_00011, CRUK Integrative Cancer Epidemiology Programme C18281/A19169, Medical Research Council UK (MRC) MC_UU_00011/1, UK National Institute for Health Research Academic Clinical Fellowship, American Heart Association 18CDA34110116, Miguel Servet contract from the ISCIII Spanish Health Institute CP17/00142, European Social Fund (ESF), Westlake Education Foundation, British Heart Foundation FS/14/66/3129 Z01HG200362 R01HL142302 R01HL105756

Older adults with dementia have difficulties communicating their treatment preferences and experience end-of-life burdensome interventions with discomfort and limited benefits. This study compared utilization of burdensome interventions during the last 90 days of life among Medicare fee-for-service (FFS) beneficiaries with no dementia, non-advanced dementia, and advanced dementia.This study utilized data from 2000-2016 Health and Retirement Study (HRS) linked with Medicare and Medicaid claims, and HRS Exit Interviews. We quantified rates of imaging tests and life-sustaining treatments during the last 90 days of life among those with no dementia, non-advanced dementia, and advanced dementia. Life-sustaining treatments include tube feeding, intensive care unit care, cardiopulmonary resuscitation, and invasive mechanical ventilation. Among patients with a claims-based diagnosis of dementia, we classified them as having advanced dementia if they had three or more activities of daily living limitations and any diagnosis of malnutrition, pressure ulcer, incontinence, or aspiration pneumonia. We used logistic regression to examine factors associated with end-of-life imaging tests and life-sustaining treatments.A higher proportion of beneficiaries with non-advanced dementia (68%) and advanced dementia (79%) had end-of-life imaging tests, compared to those without dementia (57%) (p0.01). Beneficiaries with dementia were more likely than non-dementia beneficiaries to receive these imaging tests, controlling for patient characteristics (non-advanced dementia: OR = 2.2 [95% CI 2.0-2.5]; advanced dementia: OR = 5.4 [4.5-6.5]). The proportion of receiving end-of-life life-sustaining treatments was lower among the non-advanced dementia cohort (23%), compared to non-dementia (27%) and advanced-dementia (27%) individuals (p0.01). After adjusting for patient characteristics, beneficiaries with dementia were more likely than those without dementia to receive at least one life-sustaining treatment (non-advanced dementia: OR = 1.1 [1.0-1.2]; advanced dementia: OR = 1.9 [1.6-2.3]). Younger age, survey self-respondents, beneficiaries with fewer instrumental activities of daily living limitations and no advance care planning were more likely to have end-of-life imaging tests and life-sustaining treatments.Our findings suggest that older adults with dementia, especially advanced dementia, are more likely to receive end-of-life burdensome interventions compared to individuals without dementia. Advance care planning involving patients with dementia, their families, and physicians about end-of-life treatment may improve the quality of care.

PURPOSE: The higher prevalence of cognitive impairment/ dementia among cancer survivors is likely multifactorial. Since both exposures to cytomegalovirus (CMV) and inflammation are common among elderly cancer survivors, we evaluated their contribution towards dementia. METHODS: Data from 1387 cancer survivors and 7004 participants without cancer in the 2016 wave of the Health and Retirement Study (HRS) was used in this study. Two inflammatory biomarkers, C-reactive protein (CRP) and neutrophil–lymphocyte ratio (NLR), were used to create an inflammation score. We used survey logistic regression adjusted for survey design parameters. RESULTS: CMV seropositivity was not associated with cognitive impairment among cancer survivors (p = 0.2). In addition, inflammation was associated with elevated odds of cognitive impairment (OR = 2.2, 95% CI [1.2, 4.2]). Cancer survivors who were both CMV seropositive and had increased inflammation had the highest odds of cognitive impairment compared to those who were CMV seronegative and had low inflammation (OR = 3.8, 95% CI [1.5, 9.4]). The stratified analysis among cancer survivors showed this association was seen only among cancer survivors in whom the cancer was diagnosed within three years of measurement of inflammation score and CMV serostatus (OR = 18.5; 95% CI [6.1, 56.1]). CONCLUSION: The CMV seropositivity and high inflammation was associated with higher cognitive impairment among cancer survivors. The stronger associations seen among cancer survivors diagnosed within the last three years suggest that strategies to reduce CMV activation and inflammation during or immediately after cancer treatment may be important in reducing the prevalence of cognitive impairment/ dementia among cancer survivors.

Adjusting for cell composition is critical in epigenome-wide association studies of whole blood samples. Using DNA methylation of whole blood samples (as opposed to purified cell types) and complete blood counts/flow cytometry data from 2530 participants in the Health and Retirement Study, we trained and tested a computational model that extends the number of estimated leukocyte subtypes to fifteen compared to established models with six or seven cell types. Our model, which can be applied to both Illumina 450k and EPIC microarrays, explained a larger proportion of the observed variance in whole blood DNA methylation levels than popular reference-based cell deconvolution approaches, and vastly reduced the number of false-positive findings in a reanalysis of an epigenome-wide association study of chronological age.

The epigenome likely interacts with traditional and genetic risk factors to influence blood pressure. We evaluated whether 13 previously reported DNA methylation sites (CpGs) are associated with systolic (SBP) or diastolic (DBP) blood pressure, both individually and aggregated into methylation risk scores (MRS), in 3070 participants (including 437 African ancestry (AA) and 2021 European ancestry (EA), mean age = 70.5 years) from the Health and Retirement Study. Nine CpGs were at least nominally associated with SBP and/or DBP after adjusting for traditional hypertension risk factors (p < 0.05). MRSSBP was positively associated with SBP in the full sample (β = 1.7 mmHg per 1 standard deviation in MRSSBP; p = 2.7 × 10−5) and in EA (β = 1.6; p = 0.001), and MRSDBP with DBP in the full sample (β = 1.1; p = 1.8 × 10−6), EA (β = 1.1; p = 7.2 × 10−5), and AA (β = 1.4; p = 0.03). The MRS and BP-genetic risk scores were independently associated with blood pressure in EA. The effects of both MRSs were weaker with increased age (pinteraction < 0.01), and the effect of MRSDBP was higher among individuals with at least some college education (pinteraction = 0.02). In AA, increasing MRSSBP was associated with higher SBP in females only (pinteraction = 0.01). Our work shows that MRS is a potential biomarker of blood pressure that may be modified by traditional hypertension risk factors.

Objectives This study aims to examine the relationship between childhood socioeconomic position (SEP) and cognitive function in later life within nationally representative samples of older adults in the United States and England, investigate whether these effects are mediated by later-life SEP, and determine whether social mobility from childhood to adulthood affects cognitive function and decline. Method Using data from the Health and Retirement Study (HRS) and the English Longitudinal Survey of Ageing (ELSA), we examined the relationships between measures of SEP, cognitive performance and decline using individual growth curve models. Results High childhood SEP was associated with higher cognitive performance at baseline in both cohorts and did not affect the rate of decline. This benefit dissipated after adjusting for education and adult wealth in the United States. Respondents with low childhood SEP, above median education, and high adult SEP had better cognitive performance at baseline than respondents with a similar childhood background and less upward mobility in both countries. Discussion These findings emphasize the impact of childhood SEP on cognitive trajectories among older adults. Upward mobility may partially compensate for disadvantage early in life but does not protect against cognitive decline.

Although psychiatric phenotypes are hypothesized to organize into a two-factor internalizing–externalizing structure, few studies have evaluated the structure of psychopathology in older adults, nor explored whether genome-wide polygenic scores (PGSs) are associated with psychopathology in a domain-specific manner. We used data from 6003 individuals of European ancestry from the Health and Retirement Study, a large population-based sample of older adults in the United States. Confirmatory factor analyses were applied to validated measures of psychopathology and PGSs were derived from well-powered genome-wide association studies (GWAS). Genomic SEM was implemented to construct latent PGSs for internalizing, externalizing, and general psychopathology. Phenotypically, the data were best characterized by a single general factor of psychopathology, a factor structure that was replicated across genders and age groups. Although externalizing PGSs (cannabis use, antisocial behavior, alcohol dependence, attention deficit hyperactivity disorder) were not associated with any phenotypes, PGSs for major depressive disorder, neuroticism, and anxiety disorders were associated with both internalizing and externalizing phenotypes. Moreover, the variance explained in the general factor of psychopathology increased by twofold (from 1% to 2%) using the latent internalizing or latent one-factor PGSs, derived using weights from Genomic Structural Equation Modeling (SEM), compared with any of the individual PGSs. Collectively, results suggest that genetic risk factors for and phenotypic markers of psychiatric disorders are transdiagnostic in older adults of European ancestry. Alternative explanations are discussed, including methodological limitations of GWAS and phenotypic measurement of psychiatric outcome in large-scale population-based studies.

Abstract Understanding the genomic basis of memory processes may help in combating neurodegenerative disorders. Hence, we examined the associations of common genetic variants with verbal short-term memory and verbal learning in adults without dementia or stroke (N = 53,637). We identified novel loci in the intronic region of CDH18, and at 13q21 and 3p21.1, as well as an expected signal in the APOE/APOC1/TOMM40 region. These results replicated in an independent sample. Functional and bioinformatic analyses supported many of these loci and further implicated POC1. We showed that polygenic score for verbal learning associated with brain activation in right parieto-occipital region during working memory task. Finally, we showed genetic correlations of these memory traits with several neurocognitive and health outcomes. Our findings suggest a role of several genomic loci in verbal memory processes.

We examined racial and ethnic differences in medication use for a representative US population of patients with Alzheimer's disease and related dementias (ADRD).We examined cholinesterase inhibitors and memantine initiation, non-adherence, and discontinuation by race and ethnicity, using data from the 2000-2016 Health and Retirement Study linked with Medicare and Medicaid claims.Among newly diagnosed ADRD patients (n = 1299), 26% filled an ADRD prescription ≤90 days and 36% ≤365 days after diagnosis. Among individuals initiating ADRD-targeted treatment (n = 1343), 44% were non-adherent and 24% discontinued the medication during the year after treatment initiation. Non-Hispanic Blacks were more likely than Whites to not adhere to ADRD medication therapy (odds ratio: 1.50 [95% confidence interval: 1.07-2.09]).Initiation of ADRD-targeted medications did not vary by ethnoracial group, but non-Hispanic Blacks had lower adherence than Whites. ADRD medication non-adherence and discontinuation were substantial and may relate to cost and access to care.Initiation of anti-dementia medications among newly diagnosed Alzheimer's disease and related dementias (ADRD) patients was low in all ethnoracial groups. ADRD medication non-adherence and discontinuation were substantial and may relate to cost and access to care. Compared to Whites, Blacks and Hispanics had lower use, poorer treatment adherence, and more frequent discontinuation of ADRD medication, but when controlling for disease severity and socioeconomic factors, racial disparities diminish. Our findings demonstrate the importance of adjusting for socioeconomic characteristics and disease severity when studying medication use and adherence in ADRD patients.

The pool of studies examining ethnic and racial differences in hospice use and end-of-life hospitalizations among patients with dementia is limited and results are conflicting, making it difficult to assess health care needs of underresourced racial and ethnic groups.To explore differences in end-of-life utilization of hospice and hospital services among patients with dementia by race and ethnicity.This cohort study used national survey data from the Health and Retirement Study linked with Medicare and Medicaid claims that reflected a range of socioeconomic, health, and psychosocial characteristics. Eligible participants were Medicare fee-for-service beneficiaries aged 65 years or older diagnosed with dementia who died between 2000 and 2016. Analyses were performed from June to December 2021.Race and ethnicity.We examined the frequency and costs of hospice care, emergency department (ED) visits, and hospitalizations during the last 180 days of life among Medicare decedents with dementia. We analyzed the proportion of dementia decedents with advance care planning and their end-of-life care preferences.The cohort sample included 5058 beneficiaries with dementia (mean [SD] age, 85.5 [8.0] years; 3038 women [60.1%]; 809 [16.0%] non-Hispanic Black, 357 [7.1%] Hispanic, and 3892 non-Hispanic White respondents [76.9%]). In adjusted analysis, non-Hispanic Black decedents (odds ratio [OR], 0.65; 95% CI, 0.55-0.78), nursing home residents (OR, 0.81; 95% CI, 0.71-0.93), and survey respondents represented by a proxy (OR, 0.84; 95% CI, 0.71-0.99) were less likely to use hospice, whereas older decedents (age 75-84 vs 65-74 years: OR, 1.39; 95% CI, 1.12-1.72; age ≥85 vs 65-74 years: OR, 1.39; 95% CI, 1.13-1.71), women (OR, 1.19; 95% CI, 1.05-1.35), and decedents with higher education (high school vs less than high school: OR, 1.17; 95% CI, 1.01-1.36; more than high school vs less than high school: OR, 1.32; 95% CI, 1.13-1.54), more severe cognitive impairment (OR, 1.51; 95% CI, 1.02-2.23), and more instrumental activities of daily living limitations (OR, 1.07; 95% CI, 1.01-1.12) were associated with higher hospice enrollment. A higher proportion of Black and Hispanic decedents with dementia used ED (645 of 809 [79.7%] and 274 of 357 [76.8%] vs 2753 of 3892 [70.7%]; P .001) and inpatient services (625 of 809 [77.3%] and 275 of 357 [77.0%] vs 2630 of 3892 [67.5%]; P .001) and incurred roughly 60% higher inpatient expenditures at the end of life compared with White decedents (estimated mean: Black, $23 279; 95% CI, $20 690-$25 868; Hispanic, $23 471; 95% CI, $19 532-$27 410 vs White, $14 609; 95% CI, $13 800-$15 418). A higher proportion of Black and Hispanic than White beneficiaries with dementia who were enrolled in hospice were subsequently admitted to the ED (56 of 309 [18.1%] and 22 of 153 [14.4%] vs 191 of 1967 [9.7%]; P .001) or hospital (48 of 309 [15.5%] and 17 of 153 [11.1%] vs 119 of 1967 [6.0%]; P .001) before death. The proportion of dementia beneficiaries completing advance care planning was lower among Black (146 of 704 [20.7%]) and Hispanic (66 of 308 [21.4%]) beneficiaries compared with White beneficiaries (1871 of 3274 [57.1%]). A higher proportion of Black and Hispanic decedents with dementia had written instructions choosing all care possible to prolong life (30 of 144 [20.8%] and 12 of 65 [18.4%] vs 72 of 1852 [3.9%]), whereas a higher proportion of White decedents preferred to limit care in certain situations (1708 of 1840 [92.8%] vs 114 of 141 [80.9%] and 51 of 64 [79.7%]), withhold treatments (1448 of 1799 [80.5%] vs 87 of 140 [62.1%] and 41 of 62 [66.1%]), and forgo extensive life-prolonging measures (1712 of 1838 [93.1%] vs 120 of 138 [87.0%] and 54 of 65 [83.1%]).The results of this cohort study highlight unique end-of-life care utilization and treatment preferences across racial and ethnic groups among patients with dementia. Medicare should consider alternative payment models to promote culturally competent end-of-life care and reduce low-value interventions and costs among the population with dementia.

Saliva is a widely used biological sample, especially in pediatric research, containing a heterogenous mixture of immune and epithelial cells. Associations of exposure or disease with saliva DNA methylation can be influenced by cell-type proportions. Here, we developed a saliva cell-type DNA methylation reference panel to estimate interindividual cell-type heterogeneity in whole saliva studies. Saliva was collected from 22 children (7–16 years) and sorted into immune and epithelial cells, using size exclusion filtration and magnetic bead sorting. DNA methylation was measured using the Illumina MethylationEPIC BeadChip. We assessed cell-type differences in DNA methylation profiles and tested for enriched biological pathways. Immune and epithelial cells differed at 181,577 (22.8%) DNA methylation sites (t-test p

Background Many DNA methylation-based indicators have been developed as summary measures of epigenetic aging. We examine the associations between 13 epigenetic clocks, including 4 second generation clocks, as well as the links of the clocks to social, demographic, and behavioral factors known to be related to health outcomes: sex, race/ethnicity, socioeconomic status, obesity, and lifetime smoking pack-years. Methods The Health and Retirement Study is the data source which is a nationally representative sample of Americans over age 50. Assessment of DNA methylation was based on the EPIC chip and epigenetic clocks were developed based on existing literature. Results The clocks vary in the strength of their relationships with age, with each other and with independent variables. Second generation clocks trained on health-related characteristics tend to relate more strongly to the sociodemographic and health behaviors known to be associated with health outcomes in this age group. Conclusions Users of this publicly available data set should be aware that epigenetic clocks vary in their relationships to age and to variables known to be related to the process of health change with age.

Background: Life course socioeconomic and demographic factors including educational attainment, race and ethnicity, and childhood (SES) are very powerful predictors of large inequalities in aging, morbidity, and mortality. Immune aging, including accumulation of late-differentiated, senescent-like lymphocytes and lower level of naive lymphocytes, may play a role in the development of the age-related health inequalities. However, there has been little research investigating association between socioeconomic status and immune aging, particularly age-related changes in lymphocyte percentages. Methods: This study used nationally representative data from more than 9000 US adults from the Health and Retirement Study to investigate associations between educational attainment, race and ethnicity, and childhood SES and lymphocyte percentages. Results: Respondents with lower educational attainment, Hispanic adults, and those who had a parent with less than high school education had lymphocyte percentages consistent with more highly accelerated immune aging compared to those with greater educational attainment, non-Hispanic White adults, and respondents who had parents with a high school education, respectively. Associations between education, Hispanic ethnicity, and parents' education and late differentiated senescent-like T lymphocytes (TemRA) and B cells were largely driven by cytomegalovirus (CMV) seropositivity. Conclusions: Results suggest that CMV is a major driver of observed SES inequalities in immunosenescence and may therefore be an important target for interventions. Naive T lymphocytes may be particularly affected by socioeconomic position and may therefore be of particular interest to research interested in inequalities in health and aging.

ObjectiveTo determine the contribution of common genetic variants to risk of early onset ischemic stroke (IS).MethodsWe performed a meta-analysis of genome-wide association studies of early onset IS, ages 18-59, using individual level data or summary statistics in 16,927 cases and 576,353 non-stroke controls from 48 different studies across North America, Europe, and Asia. We further compared effect sizes at our most genome-wide significant loci between early and late onset IS and compared polygenic risk scores for venous thromboembolism between early versus later onset IS.ResultsWe observed an association between early onset IS and ABO, a known stroke locus. The effect size of the peak ABO SNP, rs8176685, was significantly larger in early compared to late onset IS (OR 1.17 (95% C.I.: 1.11-1.22) vs 1.05 (0.99-1.12); p for interaction = 0.008). Analysis of genetically determined ABO blood groups revealed that early onset IS cases were more likely to have blood group A and less likely to have blood group O compared to both non-stroke controls and to late onset IS cases. Using polygenic risk scores, we observed that greater genetic risk for venous thromboembolism, another prothrombotic condition, was more strongly associated with early, compared to late, onset IS (p=0.008).ConclusionThe ABO locus, genetically predicted blood group A, and higher genetic propensity for venous thrombosis are more strongly associated with early onset IS, compared with late onset IS, supporting a stronger role of prothrombotic factors in early onset IS.

Reproductive longevity is essential for fertility and influences healthy ageing in women1,2, but insights into its underlying biological mechanisms and treatments to preserve it are limited. Here we identify 290 genetic determinants of ovarian ageing, assessed using normal variation in age at natural menopause (ANM) in about 200,000 women of European ancestry. These common alleles were associated with clinical extremes of ANM; women in the top 1% of genetic susceptibility have an equivalent risk of premature ovarian insufficiency to those carrying monogenic FMR1 premutations3. The identified loci implicate a broad range of DNA damage response (DDR) processes and include loss-of-function variants in key DDR-associated genes. Integration with experimental models demonstrates that these DDR processes act across the life-course to shape the ovarian reserve and its rate of depletion. Furthermore, we demonstrate that experimental manipulation of DDR pathways highlighted by human genetics increases fertility and extends reproductive life in mice. Causal inference analyses using the identified genetic variants indicate that extending reproductive life in women improves bone health and reduces risk of type 2 diabetes, but increases the risk of hormone-sensitive cancers. These findings provide insight into the mechanisms that govern ovarian ageing, when they act, and how they might be targeted by therapeutic approaches to extend fertility and prevent disease. Hundreds of genetic loci associated with age at menopause, combined with experimental evidence in mice, highlight mechanisms of reproductive ageing across the lifespan.

BACKGROUND Dementia is often underdiagnosed and this problem is more common among some ethnoracial groups. OBJECTIVE The objective of this study was to examine racial and ethnic disparities in the timeliness of receiving a clinical diagnosis of dementia. RESEARCH DESIGN This was a prospective cohort study. SUBJECTS A total of 3966 participants age 70 years and above with probable dementia in the Health and Retirement Study, linked with their Medicare and Medicaid claims. MEASURES We performed logistic regression to compare the likelihood of having a missed or delayed dementia diagnosis in claims by race/ethnicity. We analyzed dementia severity, measured by cognition and daily function, at the time of a dementia diagnosis documented in claims, and estimated average dementia diagnosis delay, by race/ethnicity. RESULTS A higher proportion of non-Hispanic Blacks and Hispanics had a missed/delayed clinical dementia diagnosis compared with non-Hispanic Whites (46% and 54% vs. 41%, P

Smoking is associated with dementia, but causality has not been well-established. Given smoking has a strong genetic component, we used genetic predisposition to smoking, based on a genome-wide association study (GWAS) from the GWAS & Sequencing Consortium of Alcohol and Nicotine use, as an instrumental variable. In a Mendelian randomization framework, we assessed the relationships between smoking and impaired cognitive status using the 2010 wave of the Health and Retirement Study. Cognitive status was assessed using cognition tests and categorized in three levels (normal cognition, cognitive impairment-non dementia, dementia). Smoking status was self-reported and classified into never, former, and current smoking. We used multivariable logistic regressions, Wald-type ratio estimators, and two-sample Mendelian randomization methods to examine associations and infer causal relationships. Among European genetic ancestry participants (n = 8741), current smoking was associated with cognitive impairment (OR = 1.62, 95%CI: 1.29, 2.01) relative to normal cognition. Two-sample Mendelian randomization results showed an inferred causal effect of smoking initiation on late-onset Alzheimer’s type dementia (MR-Egger: OR = 1.021, 95%CI: 1.017, 1.025). We observed no association between current smoking and dementia, or between former smoking and any cognitive status. No associations between smoking status and cognitive status were observed in the African genetic ancestry sample (n = 2501). Smoking behavior can give rise to cognitive impairment; therefore, promotion of smoking cessation is also important for brain health. Studies on dose and duration of smoking on cognition are critically needed, as well as continued research in non-European genetic ancestry study samples.

Human longevity is heritable, but genome-wide association (GWA) studies have had limited success. Here, we perform two meta-analyses of GWA studies of a rigorous longevity phenotype definition including 11,262/3484 cases surviving at or beyond the age corresponding to the 90th/99th survival percentile, respectively, and 25,483 controls whose age at death or at last contact was at or below the age corresponding to the 60th survival percentile. Consistent with previous reports, rs429358 (apolipoprotein E (ApoE) ε4) is associated with lower odds of surviving to the 90th and 99th percentile age, while rs7412 (ApoE ε2) shows the opposite. Moreover, rs7676745, located near GPR78, associates with lower odds of surviving to the 90th percentile age. Gene-level association analysis reveals a role for tissue-specific expression of multiple genes in longevity. Finally, genetic correlation of the longevity GWA results with that of several disease-related phenotypes points to a shared genetic architecture between health and longevity.

Though T-cell immunosenescence is a major risk factor for age-related diseases, susceptibility to infections, and responses to vaccines, differences in T-cell subset counts and representation by age and sex have not been determined for a large sample representative of the national population of the United States. We evaluated the counts of T-cell subsets including total, CD4+, and CD8+ T cells and their naïve (Tn), effector memory (Tem), and effector subsets, in the context of age, sex, and exposure to cytomegalovirus (CMV) infection among 8 848 Health and Retirement Study participants, a nationally representative study of adults older than 55 years. Total T cells (CD3+) and CD4+ cells declined markedly with age; CD8+ T cells declined somewhat less. While CD4+ T cell declines with age occurred for both CMV-seropositive and CMV-seronegative groups, total T cells and CD8+ cells were both substantially higher among the CMV-seropositive group. Numbers of Tn CD4+ and CD8+ cells were strongly and inversely related to age, were better conserved among women, and were independent of CMV seropositivity. By contrast, accumulation of the CD8+ and CD4+ Tem and effector subsets was CMV-associated. This is the first study to provide counts of T-cell subsets by age and sex in a national sample of US adults older than the age of 55 years. Understanding T-cell changes with age and sex is an important first step in determining strategies to reduce its impact on age-related diseases and susceptibility to infection.

ObjectiveAlzheimer disease (AD) is a common and costly neurodegenerative disorder. A large proportion of AD risk is heritable, and many genetic risk factors have been identified. The objective of this study was to test the hypothesis that cumulative genetic risk of known AD markers contributed to odds of dementia in a population-based sample.MethodsIn the US population-based Health and Retirement Study (waves 1995–2014), we evaluated the role of cumulative genetic risk of AD, with and without the APOE ε4 alleles, on dementia status (dementia, cognitive impairment without dementia, borderline cognitive impairment without dementia, and cognitively normal). We used logistic regression, accounting for demographic covariates and genetic principal components, and analyses were stratified by European and African genetic ancestry.ResultsIn the European ancestry sample (n = 8,399), both AD polygenic score excluding the APOE genetic region (odds ratio [OR] = 1.10; 95% confidence interval [CI]: 1.00–1.20) and the presence of any APOE ε4 alleles (OR = 2.42; 95% CI: 1.99–2.95) were associated with the odds of dementia relative to normal cognition in a mutually adjusted model. In the African ancestry sample (n = 1,605), the presence of any APOE ε4 alleles was associated with 1.77 (95% CI: 1.20–2.61) times higher odds of dementia, whereas the AD polygenic score excluding the APOE genetic region was not significantly associated with the odds of dementia relative to normal cognition 1.06 (95% CI: 0.97–1.30).ConclusionsCumulative genetic risk of AD and APOE ε4 are both independent predictors of dementia in European ancestry. This study provides important insight into the polygenic nature of dementia and demonstrates the utility of polygenic scores in dementia research.

Reproductive longevity is critical for fertility and impacts healthy ageing in women, yet insights into the underlying biological mechanisms and treatments to preserve it are limited. Here, we identify 290 genetic determinants of ovarian ageing, assessed using normal variation in age at natural menopause (ANM) in ∼200,000 women of European ancestry. These common alleles influence clinical extremes of ANM; women in the top 1% of genetic susceptibility have an equivalent risk of premature ovarian insufficiency to those carrying monogenicFMR1premutations. Identified loci implicate a broad range of DNA damage response (DDR) processes and include loss-of-function variants in key DDR genes. Integration with experimental models demonstrates that these DDR processes act across the life-course to shape the ovarian reserve and its rate of depletion. Furthermore, we demonstrate that experimental manipulation of DDR pathways highlighted by human genetics increase fertility and extend reproductive life in mice. Causal inference analyses using the identified genetic variants indicates that extending reproductive life in women improves bone health and reduces risk of type 2 diabetes, but increases risks of hormone-sensitive cancers. These findings provide insight into the mechanisms governing ovarian ageing, when they act across the life-course, and how they might be targeted by therapeutic approaches to extend fertility and prevent disease.

Background In increasingly ageing populations, there is an emergent need to develop a robust prediction model for estimating an individual absolute risk for all-cause mortality, so that relevant assessments and interventions can be targeted appropriately. The objective of the study was to derive, evaluate and validate (internally and externally) a risk prediction model allowing rapid estimations of an absolute risk of all-cause mortality in the following 10 years. Methods For the model development, data came from English Longitudinal Study of Ageing study, which comprised 9154 population-representative individuals aged 50–75 years, 1240 (13.5%) of whom died during the 10-year follow-up. Internal validation was carried out using Harrell’s optimism-correction procedure; external validation was carried out using Health and Retirement Study (HRS), which is a nationally representative longitudinal survey of adults aged ≥50 years residing in the United States. Cox proportional hazards model with regularisation by the least absolute shrinkage and selection operator, where optimisation parameters were chosen based on repeated cross-validation, was employed for variable selection and model fitting. Measures of calibration, discrimination, sensitivity and specificity were determined in the development and validation cohorts. Results The model selected 13 prognostic factors of all-cause mortality encompassing information on demographic characteristics, health comorbidity, lifestyle and cognitive functioning. The internally validated model had good discriminatory ability (c-index=0.74), specificity (72.5%) and sensitivity (73.0%). Following external validation, the model’s prediction accuracy remained within a clinically acceptable range (c-index=0.69, calibration slope β=0.80, specificity=71.5% and sensitivity=70.6%). The main limitation of our model is twofold: 1) it may not be applicable to nursing home and other institutional populations, and 2) it was developed and validated in the cohorts with predominately white ethnicity. Conclusions A new prediction model that quantifies absolute risk of all-cause mortality in the following 10-years in the general population has been developed and externally validated. It has good prediction accuracy and is based on variables that are available in a variety of care and research settings. This model can facilitate identification of high risk for all-cause mortality older adults for further assessment or interventions.

Recent advances in the field of genetics have produced a multitude of genomic data, which researchers are integrating increasingly into social science research. In this chapter, we discuss types of genomic data arising from the technological advances in the field of genetics including genome-wide variant data, DNA methylation, and telomere length. We outline several statistical genetics methodologies used to assess relationships between genomics and specific outcome such as genome-wide association studies, gene-region based tests, epigenetic aging clocks, and pathway enrichment tests. We highlight important social, epidemiological, and statistical considerations for incorporating genomics in the field of aging. Finally, we discuss what is on the horizon for aging, social science, and genomics.

BACKGROUND Dementia is often underdiagnosed and this problem is more common among some ethnoracial groups. OBJECTIVE The objective of this study was to examine racial and ethnic disparities in the timeliness of receiving a clinical diagnosis of dementia. RESEARCH DESIGN This was a prospective cohort study. SUBJECTS A total of 3966 participants age 70 years and above with probable dementia in the Health and Retirement Study, linked with their Medicare and Medicaid claims. MEASURES We performed logistic regression to compare the likelihood of having a missed or delayed dementia diagnosis in claims by race/ethnicity. We analyzed dementia severity, measured by cognition and daily function, at the time of a dementia diagnosis documented in claims, and estimated average dementia diagnosis delay, by race/ethnicity. RESULTS A higher proportion of non-Hispanic Blacks and Hispanics had a missed/delayed clinical dementia diagnosis compared with non-Hispanic Whites (46% and 54% vs. 41%, P

Saliva is a widely used biological sample, especially in pediatric research, containing a heterogenous mixture of immune and epithelial cells. Associations of exposure or disease with saliva DNA methylation can be influenced by cell-type proportions. Here, we developed a saliva cell-type DNA methylation reference panel to estimate interindividual cell-type heterogeneity in whole saliva studies. Saliva was collected from 22 children (7-16 years) and sorted into immune and epithelial cells, using size exclusion filtration and magnetic bead sorting. DNA methylation was measured using the Illumina MethylationEPIC BeadChip. We assessed cell-type differences in DNA methylation profiles and tested for enriched biological pathways. Immune and epithelial cells differed at 164,793 (20.7%) DNA methylation sites (t-test p < 10-8). Immune cell hypomethylated sites mapped to genes enriched for immune pathways (p < 3.2 × 10-5). Epithelial cell hypomethylated sites were enriched for cornification (p = 5.2 × 10-4), a key process for hard palette formation. Saliva immune and epithelial cells have distinct DNA methylation profiles which can drive whole saliva DNA methylation measures. A primary saliva DNA methylation reference panel, easily implemented with an R package, will allow estimates of cell proportions from whole saliva samples and improve epigenetic epidemiology studies by accounting for measurement heterogeneity by cell-type proportions.

Background Although we embarked on the era of the global increase in the ageing population, the recent declines in life expectancy simultaneously experienced by many high-income countries highlight a need for an accurate prediction model for estimating individual, rather than average, risk for mortality in older adults, based on readily accessible information about individuals’ lives, health and environment. Using advanced computer intensive statistical learning methods, we derived, evaluated and validated a prediction model of the 10-year risk for all-cause mortality in older adults from the general population. Methods The model was developed using a prospective population-based cohort of English adults aged ≥50 years old from English Longitudinal Study of Ageing study. Having included a large pool of predictors, we employed cox proportional hazards model with regularisation by the least absolute shrinkage and selection operator (Cox-Lasso) to identity the most robust predictors of mortality and quantify their relative contribution to all-cause mortality in the next 10 years. The model was internally validated using Harrell’s optimism-correction procedure followed by external validation in the Health and Retirement Study, which is a nationally representative, longitudinal survey of adults aged ≥50 years old in the United States. The model’s prediction accuracy was evaluated with calibration, discrimination, sensitivity and specificity. Results For model development, the sample comprised 9154 individuals; of these, 1240 (13.4%) died during the 10-year follow-up with an average length of survival of 70.2 months (SD=35.4). For external validation, the sample included 2575 individuals; of these, 491 (19.1%) died during the 10-year follow-up with an average length of survival of 77.7 months (SD=36.5). The prediction model selected 13 (15.5% of n=84) prognostic factors, which included increasing age, male gender, low accumulated wealth, comorbid health conditions (i.e., previous diagnoses of cancer, chronic lung disease or stroke), functional difficulties (i.e., difficulty walking 100 yards, or doing work around house and garden) and worsening memory. External validation demonstrated good discrimination (c-index=0.69), calibration (calibration slope β=0.80), specificity (73.2%) and sensitivity (72.4%). Discussion Our model is likely to provide accurate estimates of individual 10-year risk of mortality using information that is often available in patients’ reports. It is calibrated for individuals aged 50–75 years living in the UK but generalises reasonably well to other populations with similar underlying characteristics. The developed prediction model could be used to communicate risk to individuals and their families (if appropriate), guide strategies for risk reduction and design future studies targeting high risk subpopulations.

Cognitive function such as reasoning, attention, memory, and language is strongly correlated with brain aging. Compared to non-Hispanic whites, Hispanics/Latinos have a higher risk of cognitive impairment and dementia. The genetic determinants of cognitive function have not been widely explored in this diverse and admixed population. We conducted a genome-wide association analysis of cognitive function in up to 7600 middle aged and older Hispanics/Latinos (mean = 55 years) from the Hispanic Community Health Study / Study of Latinos (HCHS/SOL). Four cognitive measures were examined: the Brief Spanish English Verbal Learning Test (B-SEVLT), the Word Fluency Test (WFT), the Digit Symbol Substitution Test (DSST), the Six-Item Screener (SIS). Four novel loci were identified: one for B-SEVLT at 4p14, two for WFT at 3p14.1 and 6p21.32, and one for DSST at 10p13. These loci implicate genes highly expressed in brain and previously connected to neurological diseases (UBE2K, FRMD4B, the HLA gene complex). By applying tissue-specific gene expression prediction models to our genotype data, additional genes highly expressed in brain showed suggestive associations with cognitive measures possibly indicating novel biological mechanisms, including IFT122 in the hippocampus for SIS, SNX31 in the basal ganglia for B-SEVLT, RPS6KB2 in the frontal cortex for WFT, and CSPG5 in the hypothalamus for DSST. These findings provide new information about the genetic determinants of cognitive function in this unique population. In addition, we derived a measure of general cognitive function based on these cognitive tests and generated genome-wide association summary results, providing a resource to the research community for comparison, replication, and meta-analysis in future genetic studies in Hispanics/Latinos.