Mid-Life Vascular Risk and Rate of Physical Function Decline Among Older Adults: The Atherosclerosis Risk in Communities (ARIC) Study.

BACKGROUND: Physical function and its decline in older age may be connected to treatable vascular risk factors in mid-life. This study aimed to evaluate whether these factors affect the underlying rate of decline. METHODS: This prospective cohort included 5 481 older adults aged 67-91 in the Atherosclerosis Risk in Communities Study (mean [standard deviation {SD}] age = 75.8 [5.0], 58% women, 21% Black race) without a history of stroke. The main outcome was the rate of Short Physical Performance Battery (SPPB) decline over a median late-life follow-up of 4.8 years. Primary mid-life (aged 45-64) exposures were Visit 1 hypertension (>140/90 mm Hg or treatment), diabetes (>126 mg/dL or treatment), high cholesterol (>240 mg/dL or treatment), and smoking, and number of decades of vascular risk exposure across Visits 1-4. RESULTS: The average adjusted rate of SPPB decline (points per 5 years) for older adults was -0.79 (confidence interval [CI]: -0.87, 0.71) and was accelerated by mid-life hypertension (+57% decline vs normotension: additional decline of -0.47, 95% CI: -0.64, -0.30), diabetes (+73% decline vs no diabetes: additional decline of -0.67, 95% CI: -1.09, -0.24), elevated systolic blood pressure (+17% decline per SD: -0.16, 95% CI: -0.23, -0.10), and elevated fasting blood glucose (+16% decline per SD: -0.015, 95% CI: -0.24, -0.06). Each decade greater mid-life exposure to hypertension (+32% decline: -0.93, 95% CI: -1.25, -0.61) and diabetes (+35% decline: -1.03, 95% CI: -1.68, -0.38) was associated with faster SPPB decline. CONCLUSIONS: Mid-life control of blood pressure and diabetes may offset aging-related functional decline.

Mediation effects of diabetes and inflammation on the relationship of obesity to cognitive impairment in African Americans.

BACKGROUND: Whether diabetes and adipokine-driven inflammation explain the association of obesity to cognitive impairment is unknown. METHODS: Structural equation models estimated the total effects of waist circumference on cognitive outcomes among African American participants cross-sectionally (index exam) and longitudinally. Total effects were deconstructed into direct pathways of waist circumference to cognitive impairment and indirect mediation pathways through leptin, soluble tumor necrosis factor receptor 2 (sTNFR2), and diabetes. Waist circumference, leptin, and sTNFR2 were standardized. Cognitive impairment was defined as MMSE <21 or a z-score < -1.5 standard deviation (SD). Incident cognitive impairment was defined among those without cognitive impairment at the index exam as follow-up MMSE<21, z- score < -1.5, MMSE decline >1 point/year, or z-score decline of >0.1 SD/year. RESULTS: Among 1008 participants (70% women, mean age 62.9 years, 14.5% with obesity, 26% with diabetes), 132 (13%) had baseline cognitive impairment. Each SD higher waist circumference was associated with higher odds of cognitive impairment, odds ratio (OR) = 1.63; (95% confidence interval: 1.17, 2.24), with mediating pathways explaining 65% of the total effect (58% from diabetes; 7% from inflammation). At follow-up (mean 6.8 years), 106 of 535 (19.8%) had developed cognitive impairment. Each SD higher waist circumference was associated with higher odds of developing cognitive impairment (OR = 1.87; 95%CI: 1.18, 2.74); the direct effect of waist circumference explained 37% of the total effect and mediating pathways explained 63% (61% from diabetes; 2% from inflammation), although individual pathways were not statistically supported in the smaller sample. CONCLUSION: Diabetes, and to a lesser degree, adiposity-driven inflammation, appear to explain a substantial proportion of abdominal adiposity relationships with cognitive impairment. The impact of preventing and treating obesity on cognitive outcomes merits study.

Variation in Population Attributable Fraction of Dementia Associated With Potentially Modifiable Risk Factors by Race and Ethnicity in the US.

Importance: Identifying modifiable risk factors that are associated with dementia burden across racial and ethnic groups in the population can yield insights into the potential effectiveness of interventions in preventing dementia and reducing disparities. Objective: To calculate the population attributable fraction (PAF) of dementia associated with 12 established modifiable risk factors for all US adults, as well as separately by race and ethnicity. Design, Setting, and Participants: This cross-sectional study used survey data from nationally representative samples of US adults. PAFs were calculated using relative risks and prevalence estimates for 12 risk factors. Relative risks were taken from meta-analyses, as reported in a 2020 systematic review. Prevalence estimates for risk factors were derived from nationally representative cross-sectional survey data collected between 2011 and 2018. Combined PAFs were adjusted for risk factor communality using weights derived from the Atherosclerosis Risk in Communities (ARIC) study (1987-2018). Analyses were conducted May through October 2021. Exposures: Low education, hearing loss, traumatic brain injury, hypertension, excessive alcohol consumption, obesity, smoking, depression, social isolation, physical inactivity, diabetes, and air pollution. Main Outcomes and Measures: PAF for each dementia risk factor, a combined PAF, and the decrease in the number of prevalent dementia cases in 2020 that would be expected given a 15% proportional decrease in each exposure. Results: Among all US adults, an estimated 41.0% (95% CI, 22.7%-55.9%) of dementia cases were attributable to 12 risk factors. A 15% proportional decrease in each risk factor would reduce dementia prevalence in the population by an estimated 7.3% (95% CI, 3.7%-10.9%). The estimated PAF was greater for Black and Hispanic than it was for White and Asian individuals. The greatest attributable fraction of dementia cases was observed for hypertension (PAF, 20.2%; 95% CI, 6.3%-34.4%), obesity (PAF, 20.9%; 95% CI, 13.0%-28.8%), and physical inactivity (PAF, 20.1%; 95% CI, 9.1%-29.6%). These factors were also highest within each racial and ethnic group, although the proportions varied. Conclusions and Relevance: A large fraction of dementia cases in the US were associated with potentially modifiable risk factors, especially for Black and Hispanic individuals. Targeting and reducing these risk factors may curb the projected rise in dementia cases over the next several decades.

Dysregulation of multiple metabolic networks related to brain transmethylation and polyamine pathways in Alzheimer disease: A targeted metabolomic and transcriptomic study.

BACKGROUND: There is growing evidence that Alzheimer disease (AD) is a pervasive metabolic disorder with dysregulation in multiple biochemical pathways underlying its pathogenesis. Understanding how perturbations in metabolism are related to AD is critical to identifying novel targets for disease-modifying therapies. In this study, we test whether AD pathogenesis is associated with dysregulation in brain transmethylation and polyamine pathways. METHODS AND FINDINGS: We first performed targeted and quantitative metabolomics assays using capillary electrophoresis-mass spectrometry (CE-MS) on brain samples from three groups in the Baltimore Longitudinal Study of Aging (BLSA) (AD: n = 17; Asymptomatic AD [ASY]: n = 13; Control [CN]: n = 13) (overall 37.2% female; mean age at death 86.118 ± 9.842 years) in regions both vulnerable and resistant to AD pathology. Using linear mixed-effects models within two primary brain regions (inferior temporal gyrus [ITG] and middle frontal gyrus [MFG]), we tested associations between brain tissue concentrations of 26 metabolites and the following primary outcomes: group differences, Consortium to Establish a Registry for Alzheimer's Disease (CERAD) (neuritic plaque burden), and Braak (neurofibrillary pathology) scores. We found significant alterations in concentrations of metabolites in AD relative to CN samples, as well as associations with severity of both CERAD and Braak, mainly in the ITG. These metabolites represented biochemical reactions in the (1) methionine cycle (choline: lower in AD, p = 0.003; S-adenosyl methionine: higher in AD, p = 0.005); (2) transsulfuration and glutathione synthesis (cysteine: higher in AD, p < 0.001; reduced glutathione [GSH]: higher in AD, p < 0.001); (3) polyamine synthesis/catabolism (spermidine: higher in AD, p = 0.004); (4) urea cycle (N-acetyl glutamate: lower in AD, p < 0.001); (5) glutamate-aspartate metabolism (N-acetyl aspartate: lower in AD, p = 0.002); and (6) neurotransmitter metabolism (gamma-amino-butyric acid: lower in AD, p < 0.001). Utilizing three Gene Expression Omnibus (GEO) datasets, we then examined mRNA expression levels of 71 genes encoding enzymes regulating key reactions within these pathways in the entorhinal cortex (ERC; AD: n = 25; CN: n = 52) and hippocampus (AD: n = 29; CN: n = 56). Complementing our metabolomics results, our transcriptomics analyses also revealed significant alterations in gene expression levels of key enzymatic regulators of biochemical reactions linked to transmethylation and polyamine metabolism. Our study has limitations: our metabolomics assays measured only a small proportion of all metabolites participating in the pathways we examined. Our study is also cross-sectional, limiting our ability to directly test how AD progression may impact changes in metabolite concentrations or differential-gene expression. Additionally, the relatively small number of brain tissue samples may have limited our power to detect alterations in all pathway-specific metabolites and their genetic regulators. CONCLUSIONS: In this study, we observed broad dysregulation of transmethylation and polyamine synthesis/catabolism, including abnormalities in neurotransmitter signaling, urea cycle, aspartate-glutamate metabolism, and glutathione synthesis. Our results implicate alterations in cellular methylation potential and increased flux in the transmethylation pathways, increased demand on antioxidant defense mechanisms, perturbations in intermediate metabolism in the urea cycle and aspartate-glutamate pathways disrupting mitochondrial bioenergetics, increased polyamine biosynthesis and breakdown, as well as abnormalities in neurotransmitter metabolism that are related to AD.

Genetic and lifestyle risk factors for MRI-defined brain infarcts in a population-based setting.

OBJECTIVE: To explore genetic and lifestyle risk factors of MRI-defined brain infarcts (BI) in large population-based cohorts. METHODS: We performed meta-analyses of genome-wide association studies (GWAS) and examined associations of vascular risk factors and their genetic risk scores (GRS) with MRI-defined BI and a subset of BI, namely, small subcortical BI (SSBI), in 18 population-based cohorts (n = 20,949) from 5 ethnicities (3,726 with BI, 2,021 with SSBI). Top loci were followed up in 7 population-based cohorts (n = 6,862; 1,483 with BI, 630 with SBBI), and we tested associations with related phenotypes including ischemic stroke and pathologically defined BI. RESULTS: The mean prevalence was 17.7% for BI and 10.5% for SSBI, steeply rising after age 65. Two loci showed genome-wide significant association with BI: FBN2, p = 1.77 × 10-8; and LINC00539/ZDHHC20, p = 5.82 × 10-9. Both have been associated with blood pressure (BP)-related phenotypes, but did not replicate in the smaller follow-up sample or show associations with related phenotypes. Age- and sex-adjusted associations with BI and SSBI were observed for BP traits (p value for BI, p [BI] = 9.38 × 10-25; p [SSBI] = 5.23 × 10-14 for hypertension), smoking (p [BI] = 4.4 × 10-10; p [SSBI] = 1.2 × 10-4), diabetes (p [BI] = 1.7 × 10-8; p [SSBI] = 2.8 × 10-3), previous cardiovascular disease (p [BI] = 1.0 × 10-18; p [SSBI] = 2.3 × 10-7), stroke (p [BI] = 3.9 × 10-69; p [SSBI] = 3.2 × 10-24), and MRI-defined white matter hyperintensity burden (p [BI] = 1.43 × 10-157; p [SSBI] = 3.16 × 10-106), but not with body mass index or cholesterol. GRS of BP traits were associated with BI and SSBI (p ≤ 0.0022), without indication of directional pleiotropy. CONCLUSION: In this multiethnic GWAS meta-analysis, including over 20,000 population-based participants, we identified genetic risk loci for BI requiring validation once additional large datasets become available. High BP, including genetically determined, was the most significant modifiable, causal risk factor for BI.

Relationships of Clinical and Computed Tomography-Imaged Adiposity with Cognition in Middle-Aged and Older African Americans.

Background: Adiposity depots may differentially affect cognition. African Americans (AA) have higher rates of obesity and dementia but lower visceral adipose tissue (VAT) than whites, yet are underrepresented in studies of adiposity and cognition. Our study compared relations of cognitive function to clinical adiposity measures and computed tomography (CT)-imaged abdominal adiposity in AA. Methods: CT-imaged subcutaneous adipose tissue (SAT) and VAT measurements were obtained in the AA cohort of the Genetic Epidemiology Network of Arteriopathy Study (N = 652, mean age 68 ± 8.4 years, 74% females, 59% obese, 82% hypertensive). Clinical adiposity measures included waist circumference (WC) and body mass index (BMI). Global cognition was operationalized as a global cognitive z-score generated from the average of four cognitive domain z-scores. Generalized estimating equations were used to examine cross-sectional associations between individual standardized adiposity measures and cognition, accounting for age, sex, education, smoking status, and familial clustering. A collective model was constructed including multiple supported adiposity measures and age-by-adiposity interactions. Results: In the collective model, higher WC was associated with worse global cognition, ß = -0.12 (95%CI: -0.21, -0.03); higher SAT was associated with better cognition, ß = 0.09 (0.01, 0.18); higher BMI was associated with worse cognition at younger ages with attenuation at older ages (BMI-by-age-interaction p = .004). VAT was not significantly associated with global cognition, ß = -0.03 (-0.07, 0.02). Conclusions: WC may be the simplest and most efficient measure of adiposity to assess with respect to cognition in clinical settings, although studies to determine mechanistic effects of subcutaneous and other adiposity depots on cognition are warranted.

Neuroimaging Correlates of Cerebral Microbleeds: The ARIC Study (Atherosclerosis Risk in Communities).

BACKGROUND AND PURPOSE: Cerebral microbleed (CMB) location (deep versus strictly lobar) may elucidate underlying pathology with deep CMBs being more associated with hypertensive vascular disease and lobar CMBs being more associated with cerebral amyloid angiopathy. The objective of this study was to determine whether neuroimaging signs of vascular disease and Alzheimer pathology are associated with different types of CMBs. METHODS: Among 1677 nondemented ARIC (Atherosclerosis Risk in Communities) participants (mean age=76±5 years; 40% men; 26% black) with 3-Tesla MRI scans at the fifth examination (2011-2013), we fit multinomial logistic regression models to quantify relationships of brain volumes (Alzheimer disease signature regions, total gray matter, frontal gray matter, and white matter hyperintensity volumes), infarct frequencies (lacunar, nonlacunar, and total), and apolipoprotein E (number of ε4 alleles) with CMB location (none, deep/mixed, or strictly lobar CMBs). Models were weighted for the sample selection scheme and adjusted for age, sex, education, hypertension, ever smoking status, diabetes mellitus, race site membership, and estimated intracranial volume (brain volume models only). RESULTS: Deep/mixed and strictly lobar CMBs had prevalences of 8% and 16%, respectively. Larger white matter hyperintensity burden, greater total infarct frequency, smaller frontal volumes (in women only), and smaller total gray matter volume were associated with greater risk of both deep and lobar CMBs relative to no CMBs. Greater white matter hyperintensity volume was also associated with greater risk of deep relative to lobar CMBs. Higher lacunar and nonlacunar infarct frequencies were associated with higher risk of deep CMBs, whereas smaller Alzheimer disease signature region volume and apolipoprotein E ε4 homozygosity were associated with greater risk of lobar CMBs. CONCLUSIONS: CMBs are a common vascular pathology in the elderly. Markers of hypertensive small-vessel disease may contribute to deep CMBs while cerebral amyloid angiopathy may drive development of lobar CMBs.

Elevated serum osteoprotegerin is associated with increased left ventricular mass index and myocardial stiffness.

AIM: Osteoprotegerin (OPG) is associated with a poor prognosis in patients with heart failure with preserved ejection fraction (HFpEF). OPG has also been associated with fibrosis and collagen cross-linking, which increase arterial and left ventricle (LV) myocardial stiffness. Little is known about the relation of OPG and LV structure and function in African-Americans who are disproportionately affected by HFpEF. METHODS AND RESULTS: Our analysis included 1172 participants with preserved LV ejection fraction (>50%) from the African-American cohort in the Genetic Epidemiology Network of Arteriopathy Study (mean age 63 years, 72% female). We used diastolic wall strain indicator measured by echocardiography to assess LV myocardial stiffness. Diastolic wall strain was calculated as (LV posterior thickness at end-systole - LV posterior thickness at end-diastole)/LV posterior thickness at end-systole. Associations between OPG levels and indices of arterial and LV structure and function were evaluated by using generalized linear mixed models and adjusted for possible confounders. OPG levels were correlated with age, female sex, presence of hypertension and diabetes, and lower estimated glomerular filtration rate (P < 0.05 for all). Multivariable analysis revealed that higher OPG levels were associated with greater LV mass index, increased LV myocardial stiffness, and higher N-terminal prohormone brain natriuretic peptide levels (P < 0.05 for all). CONCLUSION: In African-Americans, higher OPG levels were associated with characteristics common in patients with HFpEF and were significantly associated with known precursors to HFpEF. These findings indicate a potential role for OPG in the pathophysiology of HFpEF in African-Americans.

Neighborhood social environment as risk factors to health behavior among African Americans: The Jackson Heart Study.

BACKGROUND: Few studies have focused on the impact of neighborhood social environment on changes in smoking and alcohol use over time among African Americans. METHOD: Jackson Heart Study participants were recruited from the Jackson, MS metropolitan area from 2000 to 2004. Neighborhood social environment was characterized using census-based neighborhood socio-economic status (NSES) and survey-derived perceptions of neighborhood social cohesion, disorder, and violence. Multinomial logistic regression was used to estimate the associations of neighborhood social environment with prevalence of smoking and alcohol use and with changes in these behaviors over time adjusted for individual sociodemographic characteristics. RESULTS: Participants (N=3166) resided in 108 census tracts. All neighborhood social environment variables were consistently associated with prevalence of current smoking at baseline (11%) and with persistence of smoking over a median of 8-years follow-up (8%). The odds of being a consistent smoker relative to never smoking was about 30% higher per 1SD higher neighborhood violence (aOR: 1.30, 95% CI: 1.16-1.46) and disorder (aOR: 1.26, 95% CI: 1.08 - 1.47) and at least 16% lower per 1SD higher in neighborhood social cohesion (aOR: 0.84, 95% CI: 0.74-0.95) and NSES (aOR: 0.79, 95% CI: 0.67-0.95). Heavy alcohol use at baseline (17%) and consistent heavy use over the study period (8%) were negatively associated with higher NSES (aOR: 0.85, 95% CI: 0.73-0.99 per 1SD increase in NSES). CONCLUSION: Favorable neighborhood social environments may reduce unhealthy behaviors among African Americans.

Relationship Between Midlife Cardiovascular Health and Late-Life Physical Performance: The ARIC Study.

OBJECTIVES: To examine the association between midlife cardiovascular health and physical performance 25 years later. DESIGN: Cohort study (Atherosclerosis Risk in Communities Study); multinomial logistic and logistic regression adjusted for demographic characteristics and clinical measures. SETTING: Four U.S. communities: Forsyth County, North Carolina; Washington County, Maryland; Minneapolis, Minnesota; and Jackson, Mississippi. PARTICIPANTS: Individuals aged 54.2 ± 5.8 at baseline (N = 15,744; 55% female, 27% black). MEASUREMENTS: Cardiovascular health was measured at baseline using the American Heart Association's Life's Simple 7 (LS7) score (0-14) and LS7 component categories (poor, intermediate, ideal) for each risk factor. The Short Physical Performance Battery (SPPB) was used to quantify physical function as ordinal (0-12) and categorical (low (0-6), fair (7-9), good (10-12) outcomes. RESULTS: Mean baseline LS7 score was 7.9 ± 2.4; 6,144 (39%) individuals returned 25 years later for the fifth ARIC examination, at which point the SPPB was administered. Of 5,916 individuals who completed the SPPB, 3,288 (50%) had good physical performance. Each 1-unit increase in LS7 score was associated with a 17% higher SPPB score (rate ratio (RR) = 1.17, 95% confidence interval (CI) = 1.15-1.19) and a 29% greater chance of having a late-life SPPB score of 10 or greater compared to SPPB score of less than 10 (RR = 1.29, 95% CI = 1.25-1.34). Ideal baseline glucose (RR = 2.53, 95% CI = 2.24-2.87), smoking (RR = 1.97, 95% CI = 1.81-2.15), blood pressure (RR = 1.70, 95% CI = 1.54-1.88), body mass index (RR = 1.51, 95% CI = 1.37-1.66), and physical activity (RR = 1.31, 95% CI = 1.20-1.43) had the strongest associations with late-life SPPB score, adjusting for other LS7 components. CONCLUSION: Better cardiovascular health during midlife may lead better physical functioning in older age.

Novel genetic loci associated with hippocampal volume.

The hippocampal formation is a brain structure integrally involved in episodic memory, spatial navigation, cognition and stress responsiveness. Structural abnormalities in hippocampal volume and shape are found in several common neuropsychiatric disorders. To identify the genetic underpinnings of hippocampal structure here we perform a genome-wide association study (GWAS) of 33,536 individuals and discover six independent loci significantly associated with hippocampal volume, four of them novel. Of the novel loci, three lie within genes (ASTN2, DPP4 and MAST4) and one is found 200 kb upstream of SHH. A hippocampal subfield analysis shows that a locus within the MSRB3 gene shows evidence of a localized effect along the dentate gyrus, subiculum, CA1 and fissure. Further, we show that genetic variants associated with decreased hippocampal volume are also associated with increased risk for Alzheimer's disease (rg=-0.155). Our findings suggest novel biological pathways through which human genetic variation influences hippocampal volume and risk for neuropsychiatric illness.

Novel genetic loci underlying human intracranial volume identified through genome-wide association.

Intracranial volume reflects the maximally attained brain size during development, and remains stable with loss of tissue in late life. It is highly heritable, but the underlying genes remain largely undetermined. In a genome-wide association study of 32,438 adults, we discovered five previously unknown loci for intracranial volume and confirmed two known signals. Four of the loci were also associated with adult human stature, but these remained associated with intracranial volume after adjusting for height. We found a high genetic correlation with child head circumference (ρgenetic = 0.748), which indicates a similar genetic background and allowed us to identify four additional loci through meta-analysis (Ncombined = 37,345). Variants for intracranial volume were also related to childhood and adult cognitive function, and Parkinson's disease, and were enriched near genes involved in growth pathways, including PI3K-AKT signaling. These findings identify the biological underpinnings of intracranial volume and their link to physiological and pathological traits.

Associations Between Serum Inflammatory Markers and Hippocampal Volume in a Community Sample.

OBJECTIVES: To quantify associations between inflammatory biomarkers and hippocampal volume (HV) and to examine effect modification according to sex, race, and age. DESIGN: Cross-sectional analyses using generalized estimating equations to account for familial clustering; standardized ß-coefficients adjusted for age, sex, race, and education. SETTING: Community cohorts in Jackson, Mississippi and Rochester, Minnesota. PARTICIPANTS: The Genetic Epidemiology Network of Arteriopathy study. MEASUREMENTS: C-reactive protein (CRP), interleukin-6 (IL-6), and soluble tumor necrosis factor receptors 1 (sTNFR-1) and 2 (sTNFR-2) from peripheral blood were measured in a sample of 773 non-Hispanic whites (61% women, aged 60.2 ± 9.8) and 514 African Americans (70% women, aged 63.9 ± 8.1) who also underwent brain magnetic resonance imaging. Biomarkers were standardized and compared according to sex, race and age with HV. RESULTS: In the full sample, higher sTNFR-1 and sTNFR-2 were associated with smaller HV. Each standard deviation (SD) increase in sTNFR-1 was associated with 59.1 mm(3) (95% confidence interval (CI) = -101.4 to -16.7 mm(3) ) smaller HV and each SD increase in sTNFR-2 associated with 48.8 mm(3) (95% CI = -92.2 to -5.3 mm(3) ) smaller HV. Relationships were stronger for sTNFR-2 in men (HV = -116.6 mm(3) for each SD increase, 95% CI = -201.0 to -32.1) than women (HV = -26.0 per SD increase, 95% CI = -72.4-20.5) and sTNFR-1 in non-Hispanic whites (HV = -84.7 mm(3) per SD increase, 95% CI = -142.2 to -27.1) than African Americans (HV = -14.1 mm(3) per SD increase, 95% CI = -78.3-50.1). Associations between IL-6 or CRP and HV were not supported. CONCLUSION: Higher levels of sTNFRs were associated cross-sectionally with smaller hippocampi. Longitudinal data are needed to determine whether these biomarkers may help to identify risk of late-life cognitive impairment.

Associations Between Inflammation and Physical Function in African Americans and European Americans with Prevalent Cardiovascular Risk Factors.

OBJECTIVES: To examine associations between inflammation and physical function and potential mediation by white matter hyperintensities (WMHs) in African Americans (AAs) and European Americans (EAs). DESIGN: Cross-sectional analysis using linear and logistic models with generalized estimating equations to account for family clustering, reporting results as regression coefficients (ß) and odds ratios (ORs) adjusted for education, alcohol, exercise, body mass index, hypertension, diabetes mellitus, heart disease, cognition, ankle-brachial index, race (site), and supported interactions. SETTING: Genetic Epidemiology Network of Arteriopathy-Genetics of Microangiopathic Brain Injury Study cohort. PARTICIPANTS: AA and EA sibships with two or more siblings with hypertension before age 60 (N = 1,960; 65% female, 51% AA, aged 26-91, 50% obese, 72% hypertensive). MEASUREMENTS: Inflammation (C-reactive protein (CRP), interleukin-6 (IL6), soluble tumor necrosis factor receptors (sTNFRs) 1 and 2, WMH volume (cm(3) ) according to magnetic resonance imaging), walking speed (cm/s) over 25 feet, and mobility difficulty (any self-reported difficulty walking half a mile). RESULTS: In separate models, inflammatory markers were associated with walking speed (sTNFR1: ß = -2.74, P < .001; sTNFR2: ß = -1.23, P = .03; CRP: ß = -1.95, P = .001; IL6: ß = -1.24, P = .03) and mobility difficulty (sTNFR1: OR = 1.36, P = .001; sTNFR2: OR = 1.25, P = .005; CRP: OR = 1.22, P = .005; IL6: OR = 1.18, P = .02); the association between WMH volume and sTNFR1 in AA (ß = 0.07, P = .06) did not reach typical statistical thresholds. WMH volume was associated with walking speed in AA (ß = -3.17, P = .02) but not with mobility difficulty (OR = 1.10, P = .54). Adjusting for WMH did not change associations. CONCLUSION: In young, middle-aged, and older adults with prevalent cardiovascular risk factors, multiple inflammatory biomarkers were associated with slower walking speed independent of microvascular disease in the brain. There was little evidence of mediation by brain WMH volume. Inflammation may contribute to physical function impairments through pathways other than brain microvascular disease, particularly in AAs.

Remnant Lipoprotein Cholesterol and Incident Coronary Heart Disease: The Jackson Heart and Framingham Offspring Cohort Studies.

BACKGROUND: Remnant lipoproteins (RLPs), the triglyceride-enriched precursors to low-density lipoprotein, are an emerging risk factor for coronary heart disease (CHD). We sought to determine the association of RLP cholesterol (RLP-C) levels with incident CHD in 2 diverse, prospective, longitudinal observational US cohorts. METHODS AND RESULTS: We analyzed cholesterol levels from serum lipoprotein samples separated via density gradient ultracentrifugation in 4114 US black participants (mean age 53.8 years, 64% women) from the Jackson Heart Study and a random sample of 818 predominantly white participants (mean age 57.3 years, 52% women) from the Framingham Offspring Cohort Study. Multivariable-adjusted hazard ratios (HRs) for RLP-C (the sum of very low-density lipoprotein3 cholesterol and intermediate-density lipoprotein cholesterol) were derived to estimate associations with incident CHD events consisting of myocardial infarction, CHD death, and revascularizations for each cohort separately and as a combined population. There were 146 CHD events in the combined population. After adjustments for age, sex, body mass index, smoking, blood pressure, diabetes, and lipid-lowering therapy for the combined population, RLP-C (HR 1.23 per 1-SD increase, 95% CI 1.06-1.42, P<0.01) and intermediate-density lipoprotein cholesterol (HR 1.26 per 1-SD increase, 95% CI 1.08-1.47, P<0.01) predicted CHD during an 8-year follow-up. Associations were attenuated by high-density lipoprotein cholesterol and ultimately lost significance with inclusion of real low-density lipoprotein cholesterol, which excludes Lp(a) and IDL cholesterol fractions. Similar associations were seen in multivariable analyses within each cohort. CONCLUSION: RLP-C levels are predictive of incident CHD in this diverse group of primary prevention subjects. Interventions aimed at reducing RLP-C to prevent CHD warrant further intensive investigation. CLINICAL TRIAL REGISTRATION: URL: http://www.ClinicalTrials.gov. Unique identifier: NCT00415415.

Forced Expiratory Volume in the First Second and Aldosterone as Mediators of Smoking Effect on Stroke in African Americans: The Jackson Heart Study.

BACKGROUND: Cigarette smoking is a risk factor for stroke, but the mechanisms by which smoking contributes to stroke are not well understood. This study aimed to evaluate the roles of lung function (represented by forced expiratory volume in the first second (FEV1)) and aldosterone as potential mediators of the association of smoking with stroke. METHODS AND RESULTS: The data were derived from 5010 Jackson Heart Study participants who had mean follow-up of 97.9 months. Using the Cox proportional hazards model, we estimated the hazard ratios of smoking for total stroke with and without adjustment for FEV1 and/or aldosterone at baseline after controlling for the confounders. The hazard ratio for current smoking (versus never smoking) was 2.70 (95% CI 1.71 to 4.25) for total stroke after adjustment for the confounders. Additional adjustment for FEV1 and aldosterone reduced the hazard ratio to 2.32 (95% CI 1.42 to 3.79), suggesting that 22.4% of the excess risk of current smoking for total stroke is mediated by these factors. FEV1 and aldosterone account for 13.1% and 12.1%, respectively, of the excess risk. The hazard ratio for FEV1 increased (0.61 versus 0.65) after including systemic inflammatory marker C-reactive protein, and the hazard ratios for aldosterone were comparable for the models that included all confounders and smoking status with or without different blood pressure measurements. CONCLUSIONS: Our findings suggest that the difference in stroke risk between current and never smokers may develop partially through pathways involving lung function and aldosterone and that the mediation effect through aldosterone is independent of blood pressure.

Association Between Periodontal Disease and Kidney Function Decline in African Americans: The Jackson Heart Study.

BACKGROUND: Chronic kidney disease (CKD) remains a prevalent public health problem that disproportionately affects African Americans, despite intense efforts targeting traditional risk factors. Periodontal disease, a chronic bacterial infection of the oral cavity, is both common and modifiable and has been implicated as a novel potential CKD risk factor. The authors seek to examine to what extent periodontal disease is associated with kidney function decline. METHODS: This retrospective cohort study examines 699 African American participants with preserved kidney function (defined by estimated glomerular filtration rate (eGFR) >60 mL/minute/1.73 m(2) at baseline) who underwent complete dental examinations as part of the Dental-Atherosclerosis Risk in Communities study (1996 to 1998) and subsequently enrolled in the Jackson Heart Study (2000 to 2004). Using multivariable Poisson regression, the authors examined the association of periodontal disease (severe versus non-severe) with incident CKD, defined as incident eGFR <60 mL/minute/1.73 m(2) and rapid (5% annualized) eGFR decline at follow-up among those with preserved eGFR at baseline. RESULTS: Mean (± SD) age at baseline was 65.4 (± 5.2) years, and 16.3% (n = 114) had severe periodontal disease. There were 21 cases (3.0%) of incident CKD after a mean follow-up of 4.8 (± 0.6) years. Compared with participants with non-severe periodontal disease, those with severe periodontal disease had a four-fold greater rate of incident CKD (adjusted incidence rate ratio 4.18 [95% confidence interval 1.68 to 10.39], P = 0.002). CONCLUSIONS: Severe periodontal disease is prevalent among a population at high risk for CKD and is associated with clinically significant kidney function decline. Further research is needed to determine if periodontal disease treatment alters the trajectory of renal deterioration.

Associations between inflammation and cognitive function in African Americans and European Americans.

OBJECTIVES: To examine associations between specific inflammatory biomarkers and cognitive function in African Americans (AAs) and European Americans (EAs) with prevalent vascular risk factors. DESIGN: Cross-sectional analysis using generalized estimating equations to account for familial clustering; standardized ß-coefficients, adjusted for age, sex, and education are reported. SETTING: Community cohort study in Jackson, Mississippi, and Rochester, Minnesota. PARTICIPANTS: Genetic Epidemiology Network of Arteriopathy (GENOA)-Genetics of Microangiopathic Brain Injury (GMBI) Study participants. MEASUREMENTS: Associations between inflammation (high-sensitivity C-reactive protein (CRP), interleukin (IL)-6, soluble tumor necrosis factor (TNF) receptor 1 and 2 (sTNFR1, sTNFR2)) and cognitive function (global, processing speed, language, memory, and executive function) were examined in AAs and EAs (N = 1,965; aged 26-95, 64% women, 52% AA, 75% with hypertension). RESULTS: In AAs, higher sTNFR2 was associated with poorer cognition in all domains (global: -0.11, P = .009; processing speed: -0.11, P < .001; language: -0.08, P = .002; memory: -0.09, P = .008; executive function: -0.07, P = .03); sTNFR1 was associated with slower processing speed (-0.08, P < .001) and poorer executive function (-0.08, P = .008); higher CRP was associated with slower processing speed (-0.04, P = .024), and higher IL6 was associated with poorer executive function (-0.07, P = .02). In EA, only higher sTNFR1 was associated with slower processing speed (-0.05, P = .007). Associations were not found between cognition and sTNFR2, CRP, or IL6 in EA. CONCLUSION: In a population with high vascular risk, adverse associations between inflammation and cognitive function were especially apparent in AAs, primarily involving markers of TNFα activity.

Locally advanced squamous cell carcinoma of the head and neck: CT texture and histogram analysis allow independent prediction of overall survival in patients treated with induction chemotherapy.

PURPOSE: To determine if computed tomographic (CT) texture and histogram analysis measurements of the primary mass are independently associated with overall survival in patients with locally advanced squamous cell carcinoma of the head and neck who were previously treated with cisplatin, 5-fluorouracil, and docetaxel (TPF) induction chemotherapy. MATERIALS AND METHODS: This institutional review board-approved retrospective study included 72 patients with locally advanced squamous cell carcinoma of the head and neck who were treated with induction TPF chemotherapy in 2004-2010. CT texture and histogram analysis of the primary mass on the pretherapy CT images were performed by using TexRAD software before and after application of spatial filters at different anatomic scales ranging from fine detail to coarse features. Cox proportional hazards models were used to examine the association between overall survival and the baseline CT imaging measurements and clinical variables. RESULTS: Primary mass entropy and skewness measurements with multiple spatial filters were associated with overall survival. Multivariate Cox regression analysis incorporating clinical and imaging variables indicated that primary mass size (hazard ratio [HR], 1.58 for each 1-cm increase; P = .018), N stage (HR, 8.77 for N3 vs N0 or N1; P = .002; HR, 4.99 for N3 vs N2; P = .001), and primary mass entropy (HR, 2.10 for each 0.5-unit increase; P = .036) and skewness (HR, 3.67 for each 1.0-unit increase; P = .009) measurements with the 1.0 spatial filter were independently associated with overall survival. CONCLUSION: Independent of tumor size, N stage, and other clinical variables, primary mass CT texture and histogram analysis parameters are associated with overall survival in patients with locally advanced squamous cell carcinoma of the head and neck who were treated with induction TPF. Online supplemental material is available for this article.

A double-masked, randomized, placebo-controlled trial of temporary endoscopic mucosal gastric electrical stimulation for gastroparesis.

BACKGROUND: Endoscopically placed, temporary gastric electrical stimulation (tGES) may relieve symptoms of gastroparesis (Gp) and predict permanent gastric electrical stimulation (GES) outcomes. OBJECTIVE: To measure effects of 72 hours of temporary GES on Gp symptoms. DESIGN, SETTING, AND PATIENTS: From 2005 to 2006, we conducted a hospital-based, randomized, placebo-controlled, crossover trial of two consecutive, 4-day sessions (session 1 and session 2), enrolling 58 patients (11 males, 47 females; mean age 46 years) with GP symptom histories of three etiologies (idiopathic, 38; diabetes mellitus, 13; postsurgical, 7). INTERVENTION: 72 continuous hours temporary GES was provided for group A during session 1, and for group B during session 2. MAIN OUTCOME MEASUREMENTS: Symptoms measured daily; gastric emptying, electrogastrography, and quality of life measured at baseline and session close. RESULTS: In session 1, vomiting decreased in both groups, but was greater with stimulation, resulting in a day 3 difference of -1.02 (95% CI, -1.62 to -0.42; P < .001). Scores did not return to baseline during washout; on day 4, the difference persisted at -1.08 (95% CI, -1.81 to -0.35; P = .005). In session 2, vomiting slightly decreased with stimulation and slightly increased without it; at day 8, the nonactivated group had nonsignificantly greater vomiting, 0.12 (-0.68 to 0.92; P = .762). An overall treatment effect of a slight, nonsignificant daily decrease in average vomiting scores, -0.12 (-0.26 to 0.03; P = .116), was observed by pooling stimulation effects across sessions. LIMITATIONS: Missing data; potential physiological imbalances between groups. CONCLUSIONS: Although overall treatment effects were not significant, differences in favor of stimulation were suggested. Barriers to observing treatment effects included a decrease in vomiting for both groups during session 1, insufficient washout, and the absence of baseline vomiting for some patients. Future studies should better define inclusion criteria, use longer washout periods, randomize by etiology and baseline physiological findings, and pursue alternative designs. ( CLINICAL TRIAL REGISTRATION NUMBER: 00432835.).