Coronary artery calcium as a marker of healthy and unhealthy aging in adults aged 75 and older: The Atherosclerosis Risk in Communities (ARIC) study

BACKGROUND AND AIMS

Coronary artery calcium (CAC) is validated for risk prediction among middle-aged adults, but there is limited research exploring implications of CAC among older adults. We used data from the Atherosclerosis Risk in Communities (ARIC) study to evaluate the association of CAC with domains of healthy and unhealthy aging in adults aged ≥75 years.

METHODS

We included 2,290 participants aged ≥75 years free of known coronary heart disease who underwent CAC scoring at study visit 7. We examined the cross-sectional association of CAC = 0, 1-999 (reference), and ≥1000 with seven domains of aging: cognitive function, hearing, ankle-brachial index (ABI), pulse-wave velocity (PWV), forced vital capacity (FVC), physical functioning, and grip strength.

RESULTS

The mean age was 80.5 ± 4.3 years, 38.6% male, and 77.7% White. 10.3% had CAC = 0 and 19.2% had CAC≥1000. Individuals with CAC = 0 had the lowest while those with CAC≥1000 had the highest proportion with dementia (2% vs 8%), hearing impairment (46% vs 67%), low ABI (3% vs 18%), high PWV (27% vs 41%), reduced FVC (34% vs 42%), impaired grip strength (66% vs 74%), and mean composite abnormal aging score (2.6 vs 3.7). Participants with CAC = 0 were less likely to have abnormal ABI (aOR:0.15, 95%CI:0.07-0.34), high PWV (aOR:0.57, 95%CI:0.41-0.80), and reduced FVC (aOR:0.69, 95%CI:0.50-0.96). Conversely, participants with CAC≥1000 were more likely to have low ABI (aOR:1.74, 95%CI:1.27-2.39), high PWV (aOR:1.52, 95%CI:1.15-2.00), impaired physical functioning (aOR:1.35, 95%CI:1.05-1.73), and impaired grip strength (aOR:1.46, 95%CI:1.08-1.99).

CONCLUSIONS

Our findings highlight CAC as a simple measure broadly associated with biological aging, with clinical and research implications for estimating the physical and physiological aging trajectory of older individuals.

Multi-omics and pathway analyses of genome-wide associations implicate regulation and immunity in verbal declarative memory performance

BACKGROUND

Uncovering the functional relevance underlying verbal declarative memory (VDM) genome-wide association study (GWAS) results may facilitate the development of interventions to reduce age-related memory decline and dementia.

METHODS

We performed multi-omics and pathway enrichment analyses of paragraph (PAR-dr) and word list (WL-dr) delayed recall GWAS from 29,076 older non-demented individuals of European descent. We assessed the relationship between single-variant associations and expression quantitative trait loci (eQTLs) in 44 tissues and methylation quantitative trait loci (meQTLs) in the hippocampus. We determined the relationship between gene associations and transcript levels in 53 tissues, annotation as immune genes, and regulation by transcription factors (TFs) and microRNAs. To identify significant pathways, gene set enrichment was tested in each cohort and meta-analyzed across cohorts. Analyses of differential expression in brain tissues were conducted for pathway component genes.

RESULTS

The single-variant associations of VDM showed significant linkage disequilibrium (LD) with eQTLs across all tissues and meQTLs within the hippocampus. Stronger WL-dr gene associations correlated with reduced expression in four brain tissues, including the hippocampus. More robust PAR-dr and/or WL-dr gene associations were intricately linked with immunity and were influenced by 31 TFs and 2 microRNAs. Six pathways, including type I diabetes, exhibited significant associations with both PAR-dr and WL-dr. These pathways included fifteen MHC genes intricately linked to VDM performance, showing diverse expression patterns based on cognitive status in brain tissues.

CONCLUSIONS

VDM genetic associations influence expression regulation via eQTLs and meQTLs. The involvement of TFs, microRNAs, MHC genes, and immune-related pathways contributes to VDM performance in older individuals.

Timing of Cognitive Test Score Decline Prior to Incident Dementia Diagnosis in Blacks and Whites: The Atherosclerosis Risk in Communities Neurocognitive Study

INTRODUCTION

Commonly occurring dementias include those of Alzheimer's, vascular, and mixtures of these and other pathologies. They are believed to evolve over many years, but that time interval has been difficult to establish. Our objective was to determine how many years in advance of a dementia diagnosis cognitive scores begin to change.

METHODS

14,086 dementia-free ARIC participants underwent a cognitive exam at baseline visit 2 (1990-1992, mean age 57 ± 5.72), and 11,244 at visit 4 (1996-1998), 5,640 at visit 5 (2011-2013), and 3,574 at visit 6 (2016-2017) with surveillance for dementias of all-causes combined. Within 5-year intervals after each visit, we compared performance on the Delayed Word Recall Test (DWRT), the Digit Symbol Substitution Test (DSST), the Word Fluency Test (WFT), and the combined mean of three cognitive tests at baseline in participants who were diagnosed with dementia within each interval versus those who survived the interval without a dementia diagnosis. Z-scores were adjusted for demographics and education in separate regression models for each visit. We plotted adjusted z-score means by time interval following each visit.

RESULTS

During follow-up 3,334, 2,821, 1,218, and 329 dementia cases were ascertained after visits 2, 4, 5, and 6, respectively. Adjusted DWRT z-scores were significantly lower 20-25 years before dementia than those who did not experience dementia within 25 years. DSST z-scores were significantly lower at 25-30 years and 3-test combination z-scores were significantly lower as early as 30-31 years before onset. The difference between dementia and non-dementia group in the visit 2 3-test combination z-score was -0.20 at 30-31 years prior to dementia diagnosis. As expected, differences between the dementia and non-dementia groups increased closer to the time of dementia occurrence, up to their widest point at 0-5 years prior to dementia diagnosis. The difference between dementia and non-dementia groups in the visit 2 3-test combination z-score at 0-5 years was -0.90. WFT z-score differences were smaller than for the DSST or DWRT and began later. Patterns were similar in Black and White participants.

CONCLUSION

DWRT, DSST, and combined 3-test z-scores were significantly lower more than 20 years prior to diagnosis in the dementia group versus the non-dementia group. Findings contribute to our knowledge of the long prodromal period in Blacks and Whites.

Effects of System-Level Factors on Race/Ethnic Differences in In-Hospital Mortality after Acute Ischemic Stroke

Introduction

Stroke mortality has declined, with differential changes by race; stroke is now the 5th leading cause of death overall, but 2nd leading cause of death in Black individuals. Little is known about recent race/ethnic and sex trends in in-hospital mortality after acute ischemic stroke (AIS) and whether system-level factors contribute to possible differences.

Methods

Using the National Inpatient Sample, adults (≥18 years) with a primary diagnosis of AIS from 2006 to 2017 (n=643,912) were identified. We assessed in-hospital mortality by race/ethnicity (White, Black, Hispanic, Asian/Pacific Islander [API], other), sex, and age. Hospitals were categorized by proportion of non-White patients served: <25% ("predominantly White patients"), 25-50% ("mixed race/ethnicity profile"), and ≥50% ("predominantly non-White patients"). Using survey adjusted logistic regression, the association between race/ethnicity and odds of mortality was assessed, adjusting for key sociodemographic, clinical, and hospital characteristics (e.g., age, comorbidities, stroke severity, do not resuscitate orders, and palliative care).

Results

Overall, mortality decreased from 5.0% in 2006 to 2.9% in 2017 (p<0.001). Comparing 2012-2017 to 2006-2011, there was a 68% reduction in mortality odds overall after adjusting for covariates, most prominent in White individuals (69%) and smallest in Black individuals (57%). Compared to White patients, Black and Hispanic patients had lower odds of mortality (adjusted odds ratio (aOR) 0.82, 95% CI 0.78-0.87 and aOR 0.93, 95% CI 0.87-1.00), primarily driven by those >65 years (age x ethnicity interaction p < 0.0001). Compared to White men, Black, Hispanic, and API men, and Black women had lower aOR of mortality. The differences in mortality between White and non-White patients were most pronounced in hospitals predominantly serving White patients (aOR 0.80, 0.74-0.87) compared to mixed hospitals (aOR 0.85, 0.79-0.91) and predominantly non-White hospitals (aOR 0.88, 0.81-0.95; interaction effect: p=0.005).

Discussion

AIS mortality decreased dramatically in recent years in all race/ethnic subgroups. Overall, non-White AIS patients had lower mortality than their White counterparts, a difference that was most striking in hospitals predominantly serving White patients. Further study is needed to understand these differences and to what extent biological, sociocultural, and system-level factors play a role.

Mitral annular calcification as a predictor of stroke in the multiethnic study of atherosclerosis

BACKGROUND

Mitral annular calcification (MAC) is associated with an increased risk for cardiovascular morbidity and mortality. This study provides recent data on the association between cardiac computed tomography (CT) derived MAC and 15 years of stroke risk in a racially diverse cohort.

METHODS

All multiethnic studies of atherosclerosis participants ( n  = 6814) who completed a cardiac CT at baseline were included in this analysis. MAC score was calculated from cardiac CT using the Agatston and volume score methods. Multivariable Cox proportional hazard regression models were used to compute hazard ratios for the association between MAC and stroke after adjusting for traditional cardiovascular risk factors, inflammatory markers, coronary artery calcium score, atrial fibrillation, and left atrial size.

RESULTS

Overall, 9% of participants (644/6814) had MAC at baseline. Over a surveillance period of 15 years, 304 strokes occurred, and 79% were ischemic strokes. After adjusting for age, sex, race/ethnicity, SBP, diabetes, smoking, fibrinogen, IL-6, high-sensitivity C-reactive protein, and coronary artery calcium score, baseline MAC was associated with increased risk for all strokes [hazard ratio 1.68; 95% confidence interval (CI) 1.22-2.30: P  = 0.0013]. When atrial fibrillation/flutter and left atrial size were included in the final multivariable model, MAC remained a predictor of all strokes (hazard ratio 1.93; 95% CI 1.22-3.05: P  < 0.0051) and ischemic stroke (hazard ratio 2.03; 95% CI 1.24-3.31: P  < 0.0046).

CONCLUSION

MAC is an independent predictor of long-term stroke risk in a racially diverse population beyond conventional cardiovascular risk factors and atrial fibrillation.

Association Between Acute Kidney Injury and Dementia in the Atherosclerosis Risk in Communities (ARIC) Study

RATIONALE & OBJECTIVE

Acute kidney injury (AKI) causes biochemical changes in the brain in animal models and is associated with adverse neurological complications in hospitalized patients. This study tested the association between AKI and incident dementia in a community-based cohort.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

Adult participants in the Atherosclerosis Risk in Communities (ARIC) study who experienced hospitalized AKI compared with participants hospitalized for other reasons (primary analysis, mean follow-up period 4.3 years) or participants without hospitalized AKI (secondary analysis).

PREDICTORS

Incident AKI, defined by ICD codes from hospital records.

OUTCOME

Incident dementia, diagnosed based on a combination of neurocognitive testing, informant interviews, ICD codes, and death certificates.

ANALYTICAL APPROACH

In the primary analysis, we estimated the propensity for hospitalized AKI and matched these participants with those hospitalized for another reason to examine the association of AKI with subsequent onset of dementia (N = 1,708). In the secondary analysis, we estimated the association between time-varying hospitalized AKI and subsequent onset of dementia using multivariable Cox proportional hazards regression models, adjusted for age, sex, race/center, education, smoking status, body mass index, baseline estimated glomerular filtration rate, baseline urinary albumin-creatinine ratio, systolic blood pressure, coronary heart disease, diabetes, hypertension, apolipoprotein E (APOE) ε4 allele, and C-reactive protein.

RESULTS

The mean age in the propensity-matched cohort was 76.1 ± 6.5 (SD) years, and 53.2% of the participants were women. People who were hospitalized with AKI had a higher risk of dementia (HR, 1.25 [95% CI, 1.02-1.52]; P = 0.03) compared with those without a hospitalization for AKI. The associations were slightly stronger in the time-varying analysis (HR, 1.69 [95% CI, 1.48-1.92]; P < 0.001). Other risk factors for dementia included older age, male sex, higher albuminuria, diabetes, current smoker status, and presence of the APOE risk alleles.

LIMITATIONS

Observational study, with AKI identified through diagnosis codes.

CONCLUSIONS

Participants who experienced a hospitalization for AKI were at increased risk of dementia.

Left Atrial Remodeling and Stroke in Patients With Sinus Rhythm and Normal Ejection Fraction: ARIC-NCS

Background Age-related left atrial (LA) structural and functional abnormalities may be related to subclinical cerebral infarcts (SCIs) and stroke. We evaluated the association of 3-dimensional echocardiographic LA contractility parameters with SCIs and stroke across the spectrum of tertiles of age increment in elderly patients with sinus rhythm, normal ejection fraction, and no history of atrial fibrillation. Methods and Results We enrolled 407 participants (mean age, 76±8 years; 40% men) from ARIC-NCS (Atherosclerosis Risk in Communities Neurocognitive Study) undergoing a brain magnetic resonance imaging and 3-dimensional echocardiographic examinations in 2011 to 2013. The sample was analyzed among age tertiles and subgroups: no cerebral magnetic resonance imaging-detectable infarcts (n=315), magnetic resonance imaging-diagnosed SCIs (n=58), and clinically diagnosed stroke (n=34). The frequency of SCIs significantly increased over age tertiles (P trend 0.023). LA global longitudinal strain-a 3-dimensional echocardiographic index of LA reservoir function-and E/e' divided by LA global longitudinal strain-an index of LA stiffness-worsened across age tertiles (P trend 0.014 and 0.001, respectively), and only in the categories of SCIs (P trend <0.001 and 0.045, respectively) and stroke (P trend 0.001 and 0.011, respectively). LA global longitudinal strain was negatively associated with increased odds of SCIs (P=0.036, P=0.008, and P=0.001, respectively) and strokes (P=0.043, P=0.015, and P=0.001, respectively) over age tertiles, with a significant interaction between age tertiles (interaction P=0.043 and P=0.010, respectively). E/e' divided by LA global longitudinal strain was positively associated with the presence of SCIs (P=0.037, P=0.007, and P=0.001, respectively) and strokes (P=0.045, P=0.007, and P=0.003, respectively) over age tertiles, with a significant interaction only for SCIs (interaction P=0.040) and not for clinical stroke. Conclusions In a large cohort study of elderly patients, among participants with sinus rhythm, normal ejection fraction, and no history of atrial fibrillation, measures of worse age-related LA reservoir function and stiffness are associated with higher odds of SCIs and stroke.

Can a Data-Driven Measure of Neuroanatomic Dementia Risk be Considered a Measure of Brain Aging?

There is an increasing interest in identifying aging-related factors which may be permissive of Alzheimer’s Disease (AD) emergence. We previously used machine learning to derive an index of neuroanatomic risk of dementia called AD pattern similarity (AD-PS) score using MRIs obtained in the Atherosclerosis Risk in Communities (ARIC) study. Here, we investigate the potential of the AD-PS scores as a brain-focused measure of biologic age. Among 1970 ARIC participants with MRI collected at ARIC Visit 5, we related AD-PS scores to three measures of aging: mortality (n=356) over 8 years of follow-up; an a priori panel of 32 proteins related to aging (N=1647); and a deficit accumulation index (DAI) based on 38 health-related measures. We found lower AD-PS scores associated with significantly lower mortality (HR=0.58, CI-95%, [0.45 - 0.75], p < 0.001) after adjusting for age, race, smoking and hypertension. Among the 32 proteins, nine were significantly associated to AD-PS scores (p < 0.05) with 4 remaining significant adjusting for multiple comparisons (Growth/differentiation factor 15, Tumor necrosis factor receptor superfamily member 1A and 1B and Collagen alpha-1(XVIII) chain). Finally, in a linear regression model after adjusting for age, race, sex, hypertension and smoking, AD-PS scores were associated with the DAI (p < 0.001). The consistent patterns of associations suggest that a data-driven measure of AD neuroanatomic risk may be capturing aspects of biologic age in older adults.

Regional Microstructural Integrity in Relation to Gait Speed: The Atherosclerosis Risk in Communities Study

Brain imaging-based biomarkers of neuropathology are associated with mobility in older adults, but the relation of regional microstructural integrity to gait speed in the context of a broader neuropathological profile is less understood. We examined cross-sectional associations of microstructural integrity with 4-meter usual-pace gait speed (cm/s) in a subsample of ARIC study participants who completed 3T MRI brain scans with diffusion tensor imaging(2011-13; n=1785; mean age=76.2±5.3, 60% Female, 28% Black). We considered total brain and six regional averages of fractional anisotropy (FA; lower=worse microstructural integrity) and mean diffusivity (MD; higher=worse microstructural integrity): frontal, temporal, parietal, occipital, anterior and posterior corpus callosum. Associations were tested in multivariable linear regression models adjusted for demographics, cardiovascular risk factors, and with and without additional neuropathological indices: total brain volume, white matter hyperintensities, infarcts, and microhemorrhages. When modeled separately, all neuropathology indices were associated with slower gait speed. Every standard deviation(SD) higher total brain FA was associated with +2.56 cm/s gait speed (95%CI: 1.64,3.48) and every SD higher MD was associated with -4.27 cm/s gait speed (-5.34,-3.20). All regional estimates were comparable. When adjusted for all other neuropathology indices, only posterior corpus callosum FA (β=1.72; 0.67,2.77), total MD (β=-1.63; -3.02,-0.25), frontal lobe MD (β=-1.76; -3.03,-0.48), and temporal lobe MD (β=-1.40; -2.78,-0.02) remained significantly associated with gait speed. Microstructural integrity is an informative measure of brain pathology in relation to mobility, with regional measures tied to executive, memory, and somatosensory function being more informative when a broader neuropathological profile is considered.

The Relationship of APOE ε4, Race, and Sex on the Age of Onset and Risk of Dementia

Objective: To investigate whether APOE ε4 genotype—an established risk factor for dementia—is associated with earlier age at diagnosis in addition to increased risk overall and in secondary analysis by race and sex.

Methods: We followed up 13,782 dementia-free individuals (n = 10,137 White, n = 3,645 Black, baseline age 60–66 years) in the Atherosclerosis Risk in Communities study for up to 30 years. Dementia was operationalized using standardized algorithms incorporating longitudinal cognitive change, proxy report, and hospital or death certificate dementia codes. We used a mixture of generalized gamma distributions to simultaneously estimate time to dementia, time to dementia-free death, and the proportion of individuals with dementia, by APOE ε4 status (≥1 vs. no alleles).

Results: Median age of dementia onset among APOE ε4 carriers was 81.7 (Blacks) and 83.3 years (Whites) compared with 82.6 (Blacks) and 85.7 years (Whites) in non-APOE ε4 carriers (p > 0.05 Blacks; p < 0.01 Whites). Age of dementia diagnosis did not differ by sex in ε4 carriers, but among non-carriers, average age was earlier in males than females regardless of race. APOE ε4 carriers had on average a higher proportion of diagnoses; results did not differ by race or sex.

Conclusions:APOE ε4 carrier status is associated with earlier age of dementia diagnosis with differences across race and sex. These findings clarify the causal role of APOE in dementia etiology, which could help better identify at-risk subgroups and may help facilitate better research trial recruitment and design.

Cognitive Impairment and Dementia After Stroke: Design and Rationale for the DISCOVERY Study

Stroke is a leading cause of the adult disability epidemic in the United States, with a major contribution from poststroke cognitive impairment and dementia (PSCID), the rates of which are disproportionally high among the health disparity populations. Despite the PSCID's overwhelming impact on public health, a knowledge gap exists with regard to the complex interaction between the acute stroke event and highly prevalent preexisting brain pathology related to cerebrovascular and Alzheimer disease or related dementia. Understanding the factors that modulate PSCID risk in relation to index stroke event is critically important for developing personalized prognostication of PSCID, targeted interventions to prevent it, and for informing future clinical trial design. The DISCOVERY study (Determinants of Incident Stroke Cognitive Outcomes and Vascular Effects on Recovery), a collaborative network of thirty clinical performance clinical sites with access to acute stroke populations and the expertise and capacity for systematic assessment of PSCID will address this critical challenge. DISCOVERY is a prospective, multicenter, observational, nested-cohort study of 8000 nondemented ischemic and hemorrhagic stroke patients enrolled at the time of index stroke and followed for a minimum of 2 years, with serial cognitive evaluations and assessments of functional outcome, with subsets undergoing research magnetic resonance imaging and positron emission tomography and comprehensive genetic/genomic and fluid biomarker testing. The overall scientific objective of this study is to elucidate mechanisms of brain resilience and susceptibility to PSCID in diverse US populations based on complex interplay between life-course exposure to multiple vascular risk factors, preexisting burden of microvascular and neurodegenerative pathology, the effect of strategic acute stroke lesions, and the mediating effect of genomic and epigenomic variation.

Neurocognitive, Quality of Life, and Behavioral Outcomes for Patients With Covert Stroke After Cardiac Surgery: Exploratory Analysis of Data From a Prospectively Randomized Trial

BACKGROUND

Asymptomatic brain ischemic injury detected with diffusion-weighted magnetic resonance imaging (DWI) is reported in more than one-half of patients after cardiac surgery. There are conflicting findings on whether DWI-detected covert stroke is associated with neurocognitive dysfunction after surgery, and it is unclear whether such ischemic injury affects quality of life or behavioral outcomes. The purpose of this study was to perform exploratory analysis on whether covert stroke after cardiac surgery is associated with delayed neurocognitive recovery 1 month after surgery, impaired quality of life, anxiety, or depression.

METHODS

Analysis of data collected in a prospectively randomized study in patients undergoing cardiac surgery testing whether basing mean arterial pressure (MAP) targets during cardiopulmonary bypass to be above the lower limit of cerebral autoregulation versus usual practices reduces the frequency of adverse neurological outcomes. A neuropsychological testing battery was administered before surgery and then 1 month later. Patients underwent brain magnetic resonance imaging (MRI) between postoperative days 3 and 5. The primary outcome was DWI-detected ischemic lesion; the primary end point was change from baseline in domain-specific neurocognitive Z scores 1 month after surgery. Secondary outcomes included a composite indicator of delayed neurocognitive recovery, quality of life measures, state and trait anxiety, and Beck Depression Inventory scores.

RESULTS

Of the 164 patients with postoperative MRI data, clinical stroke occurred in 10 patients. Of the remaining 154 patients, 85 (55.2%) had a covert stroke. There were no statistically significant differences for patients with or without covert stroke in the change from baseline in Z scores in any of the cognitive domains tested adjusted for sex, baseline cognitive score, and randomization treatment arm. The frequency of delayed neurocognitive recovery (no covert stroke, 15.1%; covert stroke, 17.6%; P = .392), self-reported quality of life measurements, anxiety rating, or depression scores were not different between those with or without DWI ischemic injury.

CONCLUSIONS

More than one-half of patients undergoing cardiac surgery demonstrated covert stroke. In this exploratory analysis, covert stroke was not found to be significantly associated with neurocognitive dysfunction 1 month after surgery; evidence of impaired quality of life, anxiety, or depression, albeit a type II error, cannot be excluded.

Association between Circulating Protein C Levels and Incident Dementia: The Atherosclerosis Risk in Communities Study

INTRODUCTION

Hemostasis depends on the delicate balance between coagulants and anticoagulants. Higher levels of circulating coagulants have been associated with higher risk of cerebral infarctions and dementia. In contrast, higher levels of circulating protein C, an endogenous anticoagulant, have been associated with lower risk of cerebral infarctions, and the association between protein C levels and the risk of dementia is unknown. The goal of this study was to evaluate the association of circulating protein C levels in midlife and late life with incident dementia.

METHODS

Circulating protein C levels were measured using blood samples collected at the midlife baseline (1987-1989) and the late-life baseline (2011-2013) among 14,462 and 3,614 participants, respectively, in the Atherosclerosis Risk in Communities study. Protein C levels were measured using enzyme-linked immunosorbent assay at midlife and a modified aptamer-based assay at late life. Participants were followed up to 2013 from midlife and up to 2017 from late life. Incident dementia was ascertained during the follow-up periods using in-person cognitive and functional assessment, informant interviews, and International Classification of Diseases codes at hospitalization discharge and on death certificates. Cause-specific Cox regression models were used to evaluate the association between quintiles of circulating protein C and incident dementia.

RESULTS

From midlife (mean age of 54), 1,389 incident dementia events were observed over a median follow-up of 23 years. From late life (mean age of 75), 353 incident dementia events were observed over a median follow-up of 4.9 years. At both midlife and late life, circulating protein C had an inverse association with incident dementia after adjusting for demographic, vascular, and hemostatic risk factors, incident stroke as time-dependent covariate, and incorporating stabilized weights based on propensity scores (quintile 5 vs. quintile 1 as the reference, midlife hazard ratio 0.80, 95% confidence interval 0.66-0.96, p value for trend 0.04; late-life hazard ratio 0.84, 95% confidence interval: 0.55-1.28, p value for trend 0.04).

DISCUSSION/CONCLUSION

Circulating protein C has an inverse association with incident dementia independent of established risk factors, including stroke. Our results suggest studying anticoagulants in addition to coagulants can increase our understanding on the relationship between hemostasis and dementia.

Longitudinal Blood Pressure Patterns from Mid-to-Late Life and Late-life Hearing Loss in the Atherosclerosis Risk in Communities Study

BACKGROUND

Hearing loss is prevalent and associated with adverse functional outcomes in older adults. Prevention thus has far-reaching implications, yet few modifiable risk factors have been identified. Hypertension may contribute to age-related hearing loss, but epidemiologic evidence is mixed. We studied a prospective cohort of 3,343 individuals from the Atherosclerosis Risk in Communities study, aged 44-65 years at baseline with up to 30 years of follow-up.

METHODS

Hearing was assessed in late-life (2016-17) using a better-ear audiometric pure tone average (PTA, 0.5, 1, 2, 4 kHz) and the Quick Speech-in-Noise (QuickSIN) test. Hypertension was defined as systolic blood pressure ≥140 mmHg, diastolic blood pressure ≥90 mmHg or antihypertensive medication use. Mid-life hypertension was defined by hypertension at two consecutive visits between 1987-89 and 1996-98. Late-life hypertension was defined in 2016-17. Late-life low blood pressure was defined as systolic blood pressure <90 mmHg or diastolic blood pressure <60 mmHg, irrespective of antihypertensive medication use. Associations between blood pressure patterns from mid-to-late-life and hearing outcomes were assessed using multivariable-adjusted linear regression.

RESULTS

Compared to persistent normotension, persistent hypertension from mid-to-late-life was associated with worse central auditory processing (difference in QuickSIN score = -0.66 points, 95% CI: -1.14, -0.17) but not with audiometric hearing.

CONCLUSIONS

Participants with persistent hypertension had poorer late-life central auditory processing. These findings suggest that hypertension may be more strongly related to hearing-related changes in the brain than in the cochlea.

Cognitive Impairment and Self-Care Among Congestive Heart Failure Patients in an Outpatient Clinic

The burden of congestive heart failure (CHF) is the greatest among older adults. Cognition is important for carrying out self-care tasks such as monitoring sodium intake, but little is known about how cognition affects self-care in acutely ill CHF patients. We aimed to assess the association between cognition and self-care in CHF patients from an outpatient diuresis clinic. Cognitive function was measured using the Mini-Mental State Exam (MMSE) and other tests representing 5 cognitive domains. The Self-Care of Heart Failure Index (SCHFI), given to a subset of participants, consisted of 22 questions each scored on an ordinal scale of 1-4 with a total score ranging from 22-88; higher scores indicated better self-care. SCHFI questions were further categorized into maintenance, management and confidence sub-scores. Multiple linear regressions were used to analyze the association between neuropsychological test scores and SCHFI scores. A total of 68 CHF patients had complete SCHFI data, with a mean age of 65.6 years and a mean total SCHFI score of 70.9 points. Nine (13.2%) patients were cognitively impaired (MMSE<24). Older age, lower education and history of stroke were associated with cognitive impairment. After adjusting for age, education, diabetes, and depressive symptoms, no associations were observed between the other neuropsychological test scores and any of the SCHFI scores. Though findings suggest that cognition is not associated with self-care, the analysis may have been underpowered. Further evaluation of a greater number of CHF patients is needed to understand the implications of cognition on self-care and provide guidance for interventions.

Midlife Plasma Aβ and Late-Life Risk of Cognitive Impairment: The Atherosclerosis Risk in Communities Study

Plasma-based biomarkers of amyloid beta (Aβ), a neuropathological hallmark of Alzheimer’s disease, show promise in predicting cognitive impairment and mapping onto cerebral amyloidosis, but little is known about how midlife plasma Aβ associates with late-life cognitive outcomes. Midlife plasma variants Aβ42 and Aβ40 were measured using a fluorimetric bead-based immunoassay in a subsample of visit 3 ARIC participants (1993-95; n=2585, mean age=59.4±5.2, 57% female, 23% African American). We investigated the relationship between midlife plasma Aβ and late-life mild cognitive impairment (MCI; n=923) and dementia (n=628) diagnosed from 2011-19. Multinomial logistic regressions estimated relative risk ratios (RRR) of MCI, dementia, and death vs normal cognitive status as a function of:(1) Aβ42:Aβ40 ratio, (2) Aβ42 and Aβ40 included as separate terms, and (3) Protected Aβ group (participants with Aβ42≥46 pg/ml and Aβ40 <233 pg/ml). Adjusters included age, sex, education, site-race, and APOE4. Every doubling of midlife plasma Aβ42:Aβ40 up to a threshold of 0.20 was associated with 41% lower risk of developing MCI/dementia in comparison to cognitively normal (RRR=0.59 [95% CI:0.42, 0.82]), with no association for ratio values ≥0.20. Every standard deviation increase in plasma Aβ42 was associated with 17% lower risk of dementia (RRR=0.83 [0.70, 0.99]), whereas every standard deviation increase in plasma Aβ40 was associated with 16% higher risk of MCI (RRR=1.16 [1.02, 1.31]). The protected midlife plasma Aβ group had 86% lower risk of late-life dementia vs all others (RRR=0.14 [0.04, 0.47]). Early measurement of plasma Aβ may prove an accessible and effective population screener for future cognitive impairment.

Association of mid-life serum lipid levels with late-life brain volumes: The atherosclerosis risk in communities neurocognitive study (ARICNCS)

BACKGROUND

Limited information exists regarding the association between midlife lipid levels and late-life total and regional brain volumes.

METHODS

We studied 1872 participants in the longitudinal community-based Atherosclerosis Risk in Communities Neurocognitive Study. Serum lipid levels were measured in 1987-1989 (mean age, 53 ± 5 years). Participants underwent 3T brain MRI scans in 2011-2013. Brain volumes were measured using FreeSurfer image analysis software. Linear regression models were used to assess the associations between serum lipids and brain volumes modeled in standard deviation (SD) units, adjusting for potential confounders.

RESULTS

In adjusted analyses, one SD higher low-density lipoprotein cholesterol (LDL) levels were associated with larger total brain volumes (β 0.033, 95% CI 0.006-0.060) as well as larger volumes of the temporal (β 0.038, 95% CI 0.003-0.074) and parietal lobes (β 0.044, 95% CI 0.009-0.07) and Alzheimer disease-related region (β 0.048, 95% CI 0.048-0.085). Higher triglyceride levels were associated with smaller total brain volumes (β -0.033, 95% CI -0.060, -0.007). The associations between LDL levels and brain volumes were modified by age (P for interaction <0.001), with higher LDL levels associated with larger total and regional brain volumes only among adults >53 years at baseline, and were attenuated after application of weights to account for informative attrition, although associations with the parietal and Alzheimer's disease-related region remained significant. High-density lipoprotein cholesterol was not associated with brain volumes.

CONCLUSION

Higher LDL levels in late midlife were associated with larger brain volumes later in life, while higher triglyceride levels were associated with smaller brain volumes. These associations were driven by adults >53 years at baseline.

Liver Enzymes and Risk of Stroke: The Atherosclerosis Risk in Communities (ARIC) Study

BACKGROUND AND PURPOSE

Liver enzymes (aspartate aminotransferase [AST], alanine aminotransferase [ALT], and gamma-glutamyl transpeptidase [GGT]) are glutamate-regulatory enzymes, and higher glutamate levels correlated with worse prognosis of patients with neurotrauma. However, less is known about the association between liver enzymes and incidence of stroke. We evaluated the association between serum levels of AST, ALT, and GGT and incidence of stroke in the Atherosclerosis Risk in Communities (ARIC) study cohort from 1990 to 1992 through December 31, 2016.

METHODS

We included 12,588 ARIC participants without prevalent stroke and with data on liver enzymes ALT, AST, and GGT at baseline. We used multivariable Cox regression models to examine the associations between liver enzymes levels at baseline and stroke risk (overall, ischemic stroke, and intracerebral hemorrhage [ICH]) through December 31, 2016, adjusting for potential confounders.

RESULTS

During a median follow-up time of 24.2 years, we observed 1,012 incident strokes (922ischemic strokes and 90 ICH). In age, sex, and race-center adjusted models, the hazard ratios (HRs; 95% confidence intervals [CIs]) for the highest compared to lowest GGT quartile were 1.94 (95% CI, 1.64 to 2.30) for all incident stroke and 2.01 (95% CI, 1.68 to 2.41) for ischemic stroke, with the results supporting a dose-response association (P for linear trend <0.001). Levels of AST were associated with increased risk of ICH, but the association was significant only when comparing the third quartile with the lowest quartile (adjusted HR, 1.82; 95% CI, 1.06 to 3.13).

CONCLUSIONS

Elevated levels of GGT (within normal levels), independent of liver disease, are associated with higher risk of incident stroke overall and ischemic stroke, but not ICH.

Genome-Wide Association Study Meta-Analysis of Stroke in 22 000 Individuals of African Descent Identifies Novel Associations With Stroke

BACKGROUND AND PURPOSE

Stroke is a complex disease with multiple genetic and environmental risk factors. Blacks endure a nearly 2-fold greater risk of stroke and are 2× to 3× more likely to die from stroke than European Americans.

METHODS

The COMPASS (Consortium of Minority Population Genome-Wide Association Studies of Stroke) has conducted a genome-wide association meta-analysis of stroke in >22 000 individuals of African ancestry (3734 cases, 18 317 controls) from 13 cohorts.

RESULTS

In meta-analyses, we identified one single nucleotide polymorphism (rs55931441) near the HNF1A gene that reached genome-wide significance (P=4.62×10-8) and an additional 29 variants with suggestive evidence of association (P<1×10-6), representing 24 unique loci. For validation, a look-up analysis for a 100 kb region flanking the COMPASS single nucleotide polymorphism was performed in SiGN (Stroke Genetics Network) Europeans, SiGN Hispanics, and METASTROKE (Europeans). Using a stringent Bonferroni correction P value of 2.08×10-3 (0.05/24 unique loci), we were able to validate associations at the HNF1A locus in both SiGN (P=8.18×10-4) and METASTROKE (P=1.72×10-3) European populations. Overall, 16 of 24 loci showed evidence for validation across multiple populations. Previous studies have reported associations between variants in the HNF1A gene and lipids, C-reactive protein, and risk of coronary artery disease and stroke. Suggestive associations with variants in the SFXN4 and TMEM108 genes represent potential novel ischemic stroke loci.

CONCLUSIONS

These findings represent the most thorough investigation of genetic determinants of stroke in individuals of African descent, to date.

Effect of Targeting Mean Arterial Pressure During Cardiopulmonary Bypass by Monitoring Cerebral Autoregulation on Postsurgical Delirium Among Older Patients: A Nested Randomized Clinical Trial

Importance

Delirium occurs in up to 52% of patients after cardiac surgery and may result from changes in cerebral perfusion. Using intraoperative cerebral autoregulation monitoring to individualize and optimize cerebral perfusion may be a useful strategy to reduce the incidence of delirium after cardiac surgery.

Objective

To determine whether targeting mean arterial pressure during cardiopulmonary bypass (CPB) using cerebral autoregulation monitoring reduces the incidence of delirium compared with usual care.

Design, Setting, and Participants

This randomized clinical trial nested within a larger trial enrolled patients older than 55 years who underwent nonemergency cardiac surgery at a single US academic medical center between October 11, 2012, and May 10, 2016, and had a high risk for neurologic complications. Patients, physicians, and outcome assessors were masked to the assigned intervention. A total of 2764 patients were screened, and 199 were eligible for analysis in this study.

Intervention

In the intervention group, the patient's lower limit of cerebral autoregulation was identified during surgery before CPB. On CPB, the patient's mean arterial pressure was targeted to be greater than that patient's lower limit of autoregulation. In the control group, mean arterial pressure targets were determined according to institutional practice.

Main Outcomes and Measures

The main outcome was any incidence of delirium on postoperative days 1 through 4, as adjudicated by a consensus expert panel.

Results

Among the 199 participants in this study, mean (SD) age was 70.3 (7.5) years and 150 (75.4%) were male. One hundred sixty-two (81.4%) were white, 26 (13.1%) were black, and 11 (5.5%) were of other race. Of 103 patients randomized to usual care, 94 were analyzed, and of 102 patients randomized to the intervention 105 were analyzed. Excluding 5 patients with coma, delirium occurred in 48 of the 91 patients (53%) in the usual care group compared with 39 of the 103 patients (38%) in the intervention group (P = .04). The odds of delirium were reduced by 45% in patients randomized to the autoregulation group (odds ratio, 0.55; 95% CI, 0.31-0.97; P = .04).

Conclusions and Relevance

The results of this study suggest that optimizing mean arterial pressure to be greater than the individual patient's lower limit of cerebral autoregulation during CPB may reduce the incidence of delirium after cardiac surgery, but further study is needed.

Trial Registration

ClinicalTrials.gov identifier: NCT00981474.

Common Genetic Variation Indicates Separate Causes for Periventricular and Deep White Matter Hyperintensities

BACKGROUND AND PURPOSE

Periventricular white matter hyperintensities (WMH; PVWMH) and deep WMH (DWMH) are regional classifications of WMH and reflect proposed differences in cause. In the first study, to date, we undertook genome-wide association analyses of DWMH and PVWMH to show that these phenotypes have different genetic underpinnings.

METHODS

Participants were aged 45 years and older, free of stroke and dementia. We conducted genome-wide association analyses of PVWMH and DWMH in 26,654 participants from CHARGE (Cohorts for Heart and Aging Research in Genomic Epidemiology), ENIGMA (Enhancing Neuro-Imaging Genetics Through Meta-Analysis), and the UKB (UK Biobank). Regional correlations were investigated using the genome-wide association analyses -pairwise method. Cross-trait genetic correlations between PVWMH, DWMH, stroke, and dementia were estimated using LDSC.

RESULTS

In the discovery and replication analysis, for PVWMH only, we found associations on chromosomes 2 (NBEAL), 10q23.1 (TSPAN14/FAM231A), and 10q24.33 (SH3PXD2A). In the much larger combined meta-analysis of all cohorts, we identified ten significant regions for PVWMH: chromosomes 2 (3 regions), 6, 7, 10 (2 regions), 13, 16, and 17q23.1. New loci of interest include 7q36.1 (NOS3) and 16q24.2. In both the discovery/replication and combined analysis, we found genome-wide significant associations for the 17q25.1 locus for both DWMH and PVWMH. Using gene-based association analysis, 19 genes across all regions were identified for PVWMH only, including the new genes: CALCRL (2q32.1), KLHL24 (3q27.1), VCAN (5q27.1), and POLR2F (22q13.1). Thirteen genes in the 17q25.1 locus were significant for both phenotypes. More extensive genetic correlations were observed for PVWMH with small vessel ischemic stroke. There were no associations with dementia for either phenotype.

CONCLUSIONS

Our study confirms these phenotypes have distinct and also shared genetic architectures. Genetic analyses indicated PVWMH was more associated with ischemic stroke whilst DWMH loci were implicated in vascular, astrocyte, and neuronal function. Our study confirms these phenotypes are distinct neuroimaging classifications and identifies new candidate genes associated with PVWMH only.

Plasma phospholipid very-long-chain SFAs in midlife and 20-year cognitive change in the Atherosclerosis Risk in Communities (ARIC): a cohort study

BACKGROUND

Very-long-chain SFAs (VLSFAs) have recently gained considerable attention as having beneficial effects on health and aging.

OBJECTIVES

The objective of this study was to assess the associations of plasma phospholipid VLSFAs [arachidic acid (20:0), behenic acid (22:0), tricosanoic acid (23:0), and lignoceric acid (24:0)] with 20-y cognitive decline in the Atherosclerosis Risk in Communities (ARIC) participants. Furthermore, this study compared the associations of plasma phospholipid VLSFAs with 5 common groups of fatty acids [i.e., total SFAs, total MUFAs, total ω-3 (n-3) PUFAs, total marine-derived ω-3 PUFAs, total ω-6 PUFAs].

METHODS

This study used a cohort study design of 3229 ARIC participants enrolled at the Minnesota field center. Fatty acids were measured at visit 1 (1987-1989); and cognition was assessed at visits 2 (1990-1992), 4 (1996-1998), and 5 (2011-2013) using 3 tests: the Delayed Word Recall Test (DWRT), the Digit-Symbol Substitution Test (DSST), and the Word Fluency Test (WFT).

RESULTS

Higher proportions of plasma phospholipid total VLSFAs and each individual VLSFA were associated with less decline in WFT, a test of verbal fluency. For example, 1 SD higher in total VLSFAs at baseline was associated with 0.057 SD (95% CI: 0.018, 0.096, P = 0.004) less cognitive decline over 20 y as measured by WFT score. None of the 5 common fatty acid groups were associated with change in WFT, but a higher proportion of plasma phospholipid total MUFAs was associated with greater decline in DWRT; higher total ω-6 PUFAs with less decline in DWRT; and higher total ω-3 and total marine-derived ω-3 PUFAs with less decline in DSST.

CONCLUSIONS

This study suggests that higher proportions of plasma phospholipid VLSFAs in midlife may be associated with less 20-y cognitive decline.

Global and Regional Development of the Human Cerebral Cortex: Molecular Architecture and Occupational Aptitudes

We have carried out meta-analyses of genome-wide association studies (GWAS) (n = 23 784) of the first two principal components (PCs) that group together cortical regions with shared variance in their surface area. PC1 (global) captured variations of most regions, whereas PC2 (visual) was specific to the primary and secondary visual cortices. We identified a total of 18 (PC1) and 17 (PC2) independent loci, which were replicated in another 25 746 individuals. The loci of the global PC1 included those associated previously with intracranial volume and/or general cognitive function, such as MAPT and IGF2BP1. The loci of the visual PC2 included DAAM1, a key player in the planar-cell-polarity pathway. We then tested associations with occupational aptitudes and, as predicted, found that the global PC1 was associated with General Learning Ability, and the visual PC2 was associated with the Form Perception aptitude. These results suggest that interindividual variations in global and regional development of the human cerebral cortex (and its molecular architecture) cascade-albeit in a very limited manner-to behaviors as complex as the choice of one's occupation.

Cardiac Biomarkers and Subsequent Risk of Hospitalization With Bleeding in the Community: Atherosclerosis Risk in Communities Study

Background

hs‐cTnT (high‐sensitivity cardiac troponin T), but not NT‐proBNP (N‐terminal pro–B natriuretic peptide), has been shown to predict bleeding in patients with atrial fibrillation. Whether these biomarkers are independently associated with bleeding in the general population is unknown.

Methods and Results

We used Cox proportional hazards models to examine the association of hs‐cTnT and NT‐proBNP with incident bleeding (defined by International Classification of Diseases, Ninth Revision [ICD‐9] codes) among 9550 middle‐aged men and women without a history of cardiovascular disease or bleeding. There were 847 hospitalizations with bleeding (92% from gastrointestinal bleeding) during a median follow‐up of 9.0 years. Serum levels of hs‐cTnT were associated with bleeding in a graded fashion, with a hazard ratio of 1.28 (95% CI, 1.06–1.59) for 6 to <9 ng/L, 1.52 (1.21–1.91) for 9 to <14, and 2.05 (1.56–2.69) for ≥14 versus <3 ng/L. For NT‐proBNP, the highest category (≥264 versus <42 pg/mL) showed a hazard ratio of 2.00 (1.59–2.61), and the remaining 3 categories had hazard ratios ranging from 1.2 to 1.3. Individuals in the highest category of both hs‐cTnT and NT‐proBNP had a hazard ratio of 3.03 (1.97–4.68) compared with those in the lowest categories.

Conclusions

In a community‐based population, elevated hs‐cTnT and NT‐proBNP were associated with bleeding‐related hospitalizations. These biomarkers may have a high utility in identifying people at high risk for bleeding. There is a need for research on the underlying mechanisms linking subclinical cardiac abnormalities and bleeding.

Abstract 92: Stroke Survivors Experience Greater Decline in Life’s Simple 7 Score for Cardiovascular Health Over 10-Year Follow-Up

Introduction: Life’s Simple 7 (LS7) is a measure of cardiovascular health based on seven domains of smoking, diet, physical activity, body mass index, blood pressure, total cholesterol, and fasting glucose. Due to secondary prevention efforts, stroke survivors may experience improvements in LS7 scores over time compared to those who did not experience a stroke.

Methods: We included participants over 45 years of age enrolled in the REasons for Geographic and Racial Differences in Stroke (REGARDS) study who had LS7 data at baseline and 10-year follow-up and did not report a history of stroke at baseline (N=7568). Of these, 361 had an adjudicated ischemic stroke between the LS7 assessments. Scores on each domain of LS7 range from 1-3 for a maximum total score of 21, where a higher score represents better cardiovascular health. A general linear model was used to test the association of having an ischemic stroke on the change in LS7 score. Covariates included the LS7 score at baseline, age, race, gender, cognitive status, and education.

Results: Findings indicated that those who were younger, African American, and had lower levels of education, experienced significant decline in LS7 scores from baseline to follow-up (Table 1). Those who had a stroke also experienced, on average, 0.25 points more decline in total LS7 scores than those who did not have a stroke (p=0.048).

Conclusions: Stroke survivors did not experience improvements in cardiovascular health due to secondary prevention after an ischemic stroke. On the contrary, they experienced significantly greater decline, indicating the need for greater efforts in lifestyle modification and secondary prevention after a stroke.

Abstract WP372: Hydration Status and Clinical Outcomes in Acute Ischemic Stroke Patients Undergoing Mechanical Thrombectomy

Introduction: Impaired hydration measured by elevated blood urea nitrogen (BUN) to creatinine ratio has been associated with worsened outcome after acute ischemic stroke. Whether hydration status is relevant for patients with acute ischemic stroke treated with mechanical thrombectomy remains unknown.

Materials and Methods: We conducted a retrospective review of consecutive acute ischemic stroke patients who underwent endovascular procedures for anterior circulation large artery occlusion at Johns Hopkins Comprehensive Stroke Centers between 2012 and 2017. A volume contracted state (VCS), was determined based on surrogate lab markers and defined as blood urea nitrogen (BUN) to creatinine ratio greater than 15. Endpoints were achievement of successful revascularization (TICI 2b or 3), early re-occlusion, and short term clinical outcomes including development of early neurological worsening and functional outcome at 3 months.

Results: Of the 158 patients who underwent an endovascular procedure, 102 patients had a final diagnosis of anterior circulation large vessel occlusion and met the inclusion criteria for analysis. Volume contracted state was present in 62/102 (61%) of patients. Successful revascularization was achieved in 75/102 (74%) of the cohort. There was no relationship between VCS and successful revascularization, but there was a 1.13 increased adjusted odds (95% CI 1.01, 1.27) of re-occlusion within 24 hours for every point higher BUN/creatinine ratio in the subset of patients who underwent radiological testing for pre-procedure planning (n=57). There was no relationship between VCS and clinical outcomes including early neurological worsening and 3 month outcome.

Conclusions: Patients with VCS and large vessel anterior circulation stroke may have a higher odds of early re-occlusion after mechanical thrombectomy than their non-VCS counterparts, but no differences in successful revascularization nor clinical outcomes were present in this cohort. These results may suggest an opportunity for the exploration of pre-procedure hydration to improve outcomes.

Abstract TMP99: White Matter Hyperintensity Progression and Subsequent Incident Stroke: A Secondary Analysis of the ACCORD Trial

Introduction: Studies have shown that the volume of white matter hyperintensity (WMH) is a risk factor for stroke, but there are scarce data exploring the relationship between WMH progression on serial MRIs and subsequent risk of stroke.

Hypothesis: We hypothesize that WMH progression in the ACCORD trial increases the risk of subsequent incident stroke.

Methods: The exposure period was from baseline to month 40, during which an MRI was performed at both baseline and month 40. The primary outcome was incident ischemic stroke after the month 40 MRI until study completion. We fit Cox models to the primary outcome and included both the baseline and month 40 WMH volume as covariates, with the hazard ratio for the month 40 WMH volume of primary interest because it represents WMH progression in this model.

Results: We included 497 patients, of whom 53.3% were male and the mean (SD) age was 62.7 (5.7) years at enrollment. Mean (SD) follow-up after the month 40 MRI was 5.2 (1.8) years. Incident stroke occurred in 17 (3.4%) patients, in whom 2 were recurrent strokes and 15 were first-ever strokes. WMH progression was associated with subsequent stroke in the Cox model (HR 1.27, 95% CI 1.03-1.57, p=0.024) and remained significant after adjusting for patient age, history of prior stroke, and cigarette smoking (HR 1.33, 95% CI 1.07-1.65, p=0.010).

Conclusions: Although this preliminary analysis is underpowered, WMH progression, independent of absolute WMH burden, may be a risk factor for future stroke in diabetic patients. This novel finding could have translational implications - specifically that interventions which reduce the progression of WMH could, in turn, reduce future risk of stroke.

Abstract WMP67: Changes in Left Atrial Strain Are Associated With Embolic Appearing Ischemic Stroke

Background: Accruing evidence suggests that changes in cardiac structure and function, irrespective of tachyarrhythmia, are responsible for thrombus formation. Although transthoracic echocardiogram (TTE) is frequently used for cardiovascular evaluation in ischemic stroke patients (IS), many cardiac features that could clarify stroke subtype are poorly characterized without optimal evaluation of the left atrium (LA). 2D speckle tracking echocardiography (STE) allows an accurate, reproducible, and detailed assessment of the LA cycle.

Methods: IS with clinically indicated TTE provided consent. LA STE was quantified using a post processing wall motion tracking software per standard definitions. Strain/strain rate (Sr) curves for the 3 components of the LA cycle: 1) Reservoir (Global longitudinal Sr (Srmax)) 2) Conductive (Early LA Sr (Sre)) and 3) Contractile (Late LA Sr (Sra)) were evaluated. The association of embolic-appearing stroke (cardioembolic or cryptogenic; ES) with LA STE features (independent variables) was tested using logistic regression (OR (95%CI)) adjusted for covariates.

Results: Participants (N=136) were 53-70yo, 57% female and 59% black. Incremental increases in Sra (worse LA contraction) were associated with >2 times greater odds of ES (2.47 (1.29-4.72)) and improvement in Smax (LA reservoir) was associated with decreased odds of ES when adjusting for demographics (0.98 (0.96-0.99)), but not in a fully adjusted model. Improvement in the corresponding emptying fractions was significantly associated with decreased odds of ES (aEF 0.93 (0.98-0.97) tEF 0.96 ( 0.93-0.99)).

Conclusions: In this study the odds of ES was higher in those with worse LA contraction and decreased with improvement in LA reservoir with corresponding decreased odds of ES with improvement in emptying fractions. LA STE is an underutilized technology and may represent a promising tool for characterization of LA performance in patients with otherwise unexplained ES.

Abstract 136: Role of Periodontal Disease on Intracranial Atherosclerosis

Introduction: Periodontal disease (PD) is a chronic inflammatory process that affects gum and teeth. Due to the role of inflammation on atherosclerosis, we assessed the hypothesis that PD is associated with asymptomatic intracranial atherosclerosis (ICAS) in the Atherosclerosis Risk In Communities (ARIC) study.

Methods: Full-mouth clinical periodontal measurements (7-indices) collected at 6 sites per tooth from 6155 subjects from the Dental Atherosclerosis in Communities Study (DARIC) without prior stroke were used to differentiate seven periodontal profile classes (PPCs). Of this cohort, a stratified subset underwent 3D time-of-flight MR angiogram and 3D high-isotropic resolution black blood MRI. ICAS was graded according to the criteria established by the Warfarin-Aspirin Symptomatic Intracranial Disease (WASID) trial. In this study, we evaluated the relationship between PD status and severe asymptomatic ICAS, defined as ≥50% stenosis.

Results: Among dentate subjects who underwent vascular imaging, 1033 (90%) had 0-50% ICAS and 112 (10%) had ≥50% ICAS. Compared to participants without gum disease (PPC-A), participants with gingivitis (PPC-C) had significantly higher odds of having ≥50% ICAS (Figure 1; Crude OR 2.1, 95% CI 1.2-3.8, p=0.015). This association strengthened after adjusting for the significant confounding variables: age, hypertension, and LDL cholesterol (Adjusted OR 2.4, 95% CI 1.3-4.5, p=0.006).

Conclusion: We report a significant association between inflammatory PD class and ≥50% asymptomatic ICAS. Because gingivitis is reversible, future studies are needed to determine if treatment of gingivitis can prevent the development and progression of ICAS, thus reducing the risk of stroke.

Abstract 133: White Matter Hyperintensity and Cardiovascular Disease Outcomes: A Secondary Analysis of the SPRINT MIND Trial

Background: The Systolic Blood Pressure Intervention Trial (SPRINT) randomized patients to a goal SBP <120 mm Hg vs. <140 mm Hg . A subset of patients enrolled in SPRINT MIND, which performed a baseline MRI and measured white matter hyperintensity volume (WMHv). We evaluated the association between WMHv and cardiovascular events.

Methods: The primary outcome was a composite of stroke, MI, ACS, decompensated CHF, or CVD death. The secondary outcome was stroke. The WMHv was divided into quartiles. We fit Cox models to the outcomes and report adjusted hazard ratios for the quartiles of WMHv, and stratified by SPRINT treatment arm.

Results: Among 719 included patients, the mean WMHv in the quartiles was 0.34, 1.09, 2.61, and 10.8 mL. The primary outcome occurred in 51/719 (7.1%) and the secondary outcome in 10/719 (1.4%). The WMHv was associated with both outcomes (Table 1, Figure 1). After stratifying by treatment arm, we found the association persisted in the standard, but not intensive, treatment arm (Table 2). However, the interaction term between WMHv and treatment arm was not significant.

Conclusions: We observed that degree of WMH was associated with CVD and stroke risk in SPRINT MIND. The risk may be attenuated in patients randomized to intensive BP lowering. Trials are needed to determine if intensive BP lowering can prospectively reduce the high cardiovascular risk in patients with WMH.

Abstract WMP14: Association of Systolic Blood Pressure, LDL Cholesterol, and Hgb A1c With White Matter Hyperintensity on MRI in the ACCORDION MIND Study

Introduction: While retrospective studies have shown that poor control of vascular risk factors is associated with progression of white matter hyperintensity (WMH), it has not been studied prospectively.

Hypothesis: We hypothesize that higher systolic blood pressure (SBP) mean, LDL cholesterol, and Hgb A1c will be correlated with WMH progression in diabetics.

Methods: This is a secondary analysis of the Memory in Diabetes (MIND) substudy of the Action to Control Cardiovascular Risk in Diabetes Follow-on Study (ACCORDION). The primary outcome was WMH progression, evaluated by fitting linear regression models to the WMH volume on the month 80 MRI and adjusting for the WMH volume on the baseline MRI. The primary predictors were the mean values of SBP, LDL, and A1c from baseline to month 80. We defined a good vascular risk factor profile as mean SBP <120 mm Hg and mean LDL <120 mg/dL.

Results: We included 292 patients, with a mean (SD) age of 62.6 (5.3) years and 55.8% male. The mean number of SBP, LDL, and A1c measurements per patient was 17, 5, and 12. We identified 86 (29.4%) patients with good vascular risk factor profile. In the linear regression models, mean SBP and LDL were associated with WMH progression and in a second fully adjusted model they both remained associated with WMH progression (Table). Those with a good vascular risk factor profile had less WMH progression (β Coefficient -0.80, 95% CI -1.42, -0.18, p=0.012).

Conclusions: Our data reinforce prior research showing that higher SBP and LDL is associated with progression of WMH in diabetics, likely secondary to chronic microvascular ischemia, and suggest that control of these factors may have protective effects. This study has unique strengths, including prospective serial measurement of the exposures, validated algorithmic measurement methodology for WMH, and rigorous adjudication of study data. Clinical trials are needed to investigate the effect of vascular risk factor reduction on WMH progression.

Atrial Fibrillation, Brain Volumes, and Subclinical Cerebrovascular Disease (from the Atherosclerosis Risk in Communities Neurocognitive Study [ARIC-NCS])

The aim of the present study was to investigate the association between atrial fibrillation (AF) and total and regional brain volumes among participants in the community-based Atherosclerosis Risk in Communities Neurocognitive study (ARIC-NCS). A total of 1,930 participants (130 with AF) with a mean age of 76.3 ± 5.2, who underwent 3T brain MRI scans in 2011 to 2013 were included. Prevalent AF was ascertained from study ECGs and hospital discharge codes. Brain volumes were measured using FreeSurfer image analysis software. Markers of subclinical cerebrovascular disease included lobar microhemorrhages, subcortical microhemorrhages, cortical infarcts, subcortical infarcts, lacunar infarcts, and volume of white matter hyperintensities. Linear regression models were used to assess the associations between AF status and brain volumes. In adjusted analyses, AF was not associated with markers of subclinical cerebrovascular disease. However, AF was associated with smaller regional brain volumes (including temporal, occipital, and parietal lobes; deep gray matter; Alzheimer disease signature region; and hippocampus [all p <0.05]) after controlling for demographics, cardiovascular risk factors, prevalent cardiovascular disease, and markers of subclinical cerebrovascular disease. Subgroup analysis revealed a significant interaction between AF and total brain volume with respect to age (p = 0.02), with associations between AF and smaller brain volumes being stronger for older individuals. In conclusion, AF was associated with smaller brain volumes, and the association was stronger among older individuals. This finding may be related to the longer exposure period of the older population to AF or the possibility that older people are more susceptible to the effects of AF on brain volume.

Antihypertensive medications and risk for incident dementia and Alzheimer's disease: a meta-analysis of individual participant data from prospective cohort studies

BACKGROUND

Dementia is a major health concern for which prevention and treatment strategies remain elusive. Lowering high blood pressure with specific antihypertensive medications (AHMs) could reduce the burden of disease. We investigated whether specific AHM classes reduced the risk for dementia.

METHODS

We did a meta-analysis of individual participant data from eligible observational studies published between Jan 1, 1980, and Jan 1, 2019. Cohorts were eligible for inclusion if they prospectively recruited community-dwelling adults; included more than 2000 participants; collected data for dementia events over at least 5 years; had measured blood pressure and verified use of AHMs; included in-person exams, supplemented with additional data, to capture dementia events; and had followed up cases for mortality. We assessed the association of incident dementia and clinical Alzheimer's disease with use of five AHM classes, within strata of baseline high (systolic blood pressure [SBP] ≥140 mm Hg or diastolic blood pressure [DBP] ≥90 mm Hg) and normal (SBP <140 mm Hg and DBP <90 mm Hg) blood pressure. We used a propensity score to control for confounding factors related to the probability of receiving AHM. Study-specific effect estimates were pooled using random-effects meta-analyses.

RESULTS

Six prospective community-based studies (n=31 090 well phenotyped dementia-free adults older than 55 years) with median follow-ups across cohorts of 7-22 years were eligible for analysis. There were 3728 incident cases of dementia and 1741 incident Alzheimer's disease diagnoses. In the high blood pressure stratum (n=15 537), those using any AHM had a reduced risk for developing dementia (hazard ratio [HR] 0·88, 95% CI 0·79-0·98; p=0·019) and Alzheimer's disease (HR 0·84, 0·73-0·97; p=0·021) compared with those not using AHM. We did not find any significant differences between one drug class versus all others on risk of dementia. In the normal blood pressure stratum (n=15 553), there was no association between AHM use and incident dementia or Alzheimer's disease.

INTERPRETATION

Over a long period of observation, no evidence was found that a specific AHM drug class was more effective than others in lowering risk of dementia. Among people with hypertensive levels of blood pressure, use of any AHM with efficacy to lower blood pressure might reduce the risk for dementia. These findings suggest future clinical guidelines for hypertension management should also consider the beneficial effect of AHM on the risk for dementia.

FUNDING

The Alzheimer's Drug Discovery Foundation and the National Institute on Aging Intramural Research Program.

NEUROPATHOLOGY AND GAIT SPEED DECLINE IN OLDER ADULTS: THE ATHEROSCLEROSIS RISK IN COMMUNITIES (ARIC) STUDY

Neuropathological markers including amyloid-beta (Aβ) have been implicated in mobility decline in older adults, but no studies have examined the relationship between these markers and longitudinal change in gait speed in a racially diverse community-based sample. In the multi-site prospective ARIC study, a subsample of participants (n=1,978, mean age=76.3, 28.5% black) underwent brain MRI at Visit 5 (2011-13). Of these, 343 participants (mean age=75.9, 42.6% black) completed PET scans using the tracer florbetapir to estimate global brain Aβ. We investigated the relationship between four neuropathological markers [white matter hyperintensities (WMH; log2cm3), infarcts (present/absent), brain atrophy (log2cm3), and global Aβ (log2SUVR)] with cross-sectional usual pace gait speed (cm/s) over 4 meters, and change in gait speed through Visits 6 (2016-17) and 7 (2018-19). Linear regression models were adjusted for age, site, sex, education, BMI, intracranial volume, and all race interactions. Cross-sectionally, slower gait was associated with higher WMH volume (β=-2.16, 95%CI: -2.92, -1.39), infarcts (β=-5.81, 95%CI: -7.86, -3.76), and brain atrophy (β=-16.39, 95%CI: -21.07, -11.71). Longitudinally, only higher WMH volume was statistically associated with gait speed decline (β=-0.14, 95%CI: -0.28, -0.01). Global Aβ was not statistically associated with gait speed cross-sectionally (β=-.269, 95%CI: -8.11, 7.57) or longitudinally (β=-1.16, 95%CI: -2.94, 0.62). There were no significant interactions with race. Detrimental relations of cerebral small vessel disease to mobility and mobility decline were observed across race in this diverse sample. The magnitude of the Aβ association with gait speed decline was high, although not statistically significant in the smaller PET subsample.

THE RELATIONSHIP OF APOE ε4 TO THE RELATIVE TIMES AND HAZARDS OF DEMENTIA

Although APOE ε4 is an established risk factor for dementia, it is unclear whether it is associated with elevated risk or earlier symptom onset. Longitudinal study of 10,400 white-race individuals in the ARIC cohort followed from age 60 to incident dementia diagnosis, death, or censoring. All-cause dementia was defined using standardized algorithms incorporating longitudinal cognitive change, proxy report, and hospital or death certificate dementia codes. Death was ascertained via the National Death Index and death certificates. We used a parametric mixture of generalized gamma distributions to simultaneously estimate the distribution of event times and the proportion of individuals who experience each outcome (i.e., dementia and its competing risk, dementia-free death) by APOE ε4 status (≥ 1 allele vs. no alleles). Age-adjustment was through use of age as the time scale. APOE ε4 carrier status was associated with a doubling of the overall frequency of dementia incidence to 25% compared to 13% (p < 0.001) in non- ε4 carriers. The distributions of time to dementia was modified by APOE ε4 status (p=0.007): median time to dementia onset among APOE ε4 carriers was 81.9 years compared to 83.3 years in non-APOE ε4 carriers (p = 0.005). No differences in results were found by sex. APOE ε4 carrier status is associated with both elevated risk and earlier time to dementia onset. These findings clarify the causal role of APOE in dementia etiology, could help better identify at-risk subgroups, and may help facilitate better research recruitment.

HEARING IMPAIRMENT, COGNITIVE PERFORMANCE, AND BETA-AMYLOID DEPOSITION IN THE ARIC-PET AMYLOID IMAGING STUDY

Hearing impairment is a risk factor for dementia but the mechanism underlying this association is unknown. We investigated the relationship between hearing and cognitive performance and brain β-amyloid deposition in 252 adults aged 67-88 years (37% black race) without dementia from three U.S. communities. Global cortical standardized uptake value ratios (SUVRs) were calculated from florbetapir-positron emission tomography scans, with elevated SUVR defined as >1.2 (the median value). Air conduction hearing threshold levels for the frequencies of 0.5, 1, 2 and 4 kHz were obtained by pure tone audiometry and averaged for the better-hearing ear to yield a pure tone average (PTA) in decibels hearing level (dB). A composite cognitive score was created from ten neuropsychological tests summarized using latent variable methods. Multivariable-adjusted linear and Poisson regression with robust standard errors were used to estimate the average difference in cognitive scores and prevalence of elevated SUVR, respectively, by hearing impairment status. In analyses adjusted for age, sex, education and APOE ε4 status, hearing was not associated with elevated SUVR [prevalence ratio per 10 db increase (worse hearing) = 0.94 (95% CI: 0.84, 1.04)]. Results did not differ by race. In contrast, each 10 db increase in hearing impairment was associated with 0.08 standard deviation (95% CI: 0.02, 0.15) lower cognitive score, after adjustment for demographic and cardiovascular factors. Poorer hearing is associated with poorer cognitive performance but not with amyloid deposition, suggesting that the mechanism underlying the relationship between hearing and cognition may be independent of Alzheimer’s-related pathologic brain changes.

High-Sensitive Troponin T, Natriuretic Peptide, and Cognitive Change

OBJECTIVES

Cardiac troponin T, measured using a high-sensitive assay (hs-cTnT), and N-terminal pro-B-type natriuretic peptide (NT-proBNP) are associated with increased stroke risk and perhaps with cognitive decline. However, few well-designed prospective studies with extended follow-up have been conducted. We aimed to estimate the association of hs-cTnT and NT-proBNP with 15-year cognitive change in the Atherosclerosis Risk in Communities (ARIC) study.

DESIGN

Prospective cohort study.

SETTING

Four US communities.

PARTICIPANTS

A total of 9114 and 9108 participants from the Atherosclerosis Risk in Communities study for analyses of hs-cTnT and NT-proBNP, respectively.

MEASUREMENTS

We examined association of hs-cTnT and NT-proBNP with 15-year change (1996-1998 to 2011-2013) in three cognitive tests of executive function (Digit Symbol Substitution Test), verbal learning memory (Delayed Word Recall Test), and semantic fluency (Word Fluency Test), and an overall score combining the three tests using multivariable linear mixed effect models. We conducted several sensitivity analyses including multiple imputations to address bias due to missing data and attrition, and we compared associations within groups combining hs-cTnT and NT-proBNP into a three-level categorical variable.

RESULTS

At baseline (1996-1998), mean age was 63.4 (standard deviation [SD] = 5.7) years; 56.4% were women, and 17.5% were black. The hs-cTnT at baseline was not associated with cognitive change in any measure. Some evidence indicated accelerated decline in verbal learning and memory when comparing those in the highest with the lowest NT-proBNP quintiles; however, this association was not replicated when considering clinically relevant cutoffs or deciles of exposure in survivors. Sensitivity analyses were consistent with our primary analyses. There was little evidence to support effect modification by any considered factors. People with highest levels of both biomarkers had excessive decline in global z scores vs people with lowest levels (-.34; 95% confidence interval = -.63 to -.04).

CONCLUSION

Markers of myocardial injury and stretch were not associated with cognitive decline following 15 years among survivors, but when combined together they were suggestive in post hoc analysis. Whether this represents targets of intervention should be examined in the future. J Am Geriatr Soc 67:2353-2361, 2019.

Is There Equipoise Regarding the Optimal Medical Treatment of Patients with Asymptomatic White Matter Hyperintensities?

BACKGROUND

White matter hyperintensity (WMH) is a common manifestation of chronic ischemic microvascular disease that heralds greater risk of functional disability, stroke, and dementia. SPRINT MIND recently reported that intensive blood pressure reduction resulted in lower rates of mild cognitive impairment and WMH progression, suggesting that medical interventions could have a measurable impact on WMH. We conducted an anonymous survey of providers in the NINDS StrokeNet to better understand neurologist attitudes about asymptomatic WMH.

METHODS

We sent a 7-question survey to the 29 Regional Coordinating Centers of the StrokeNet, whose coordinators disseminated the survey to providers "involved in the care of a patient after their stroke."

RESULTS

We received 136 responses. For stroke prevention therapies, including aspirin and statin therapy and blood pressure target, there was substantial equipoise, with no single option receiving >50% endorsement and between 15-32% of respondents choosing the option of "not sure." 83% of respondents indicated high or moderate enthusiasm for a trial targeting this patient population. The clinical outcomes of reduction in ischemic stroke, cognitive impairment, or dementia were high importance (>70% endorsement), while the remaining radiographic, safety, and clinical endpoints all failed to reach 50% endorsement.

CONCLUSIONS

Our survey establishes meaningful neurologist attitudes that can inform future WMH research. There is considerable equipoise regarding optimal medical treatment for patients with asymptomatic WMH and providers in StrokeNet, who would be a vital stakeholder in WMH research in the United States, enthusiastically support a clinical trial to resolve open questions on optimal medical management.

Cerebral Small Vessel, But Not Large Vessel Disease, Is Associated With Impaired Cerebral Autoregulation During Cardiopulmonary Bypass: A Retrospective Cohort Study

BACKGROUND

Impaired cerebral blood flow (CBF) autoregulation during cardiopulmonary bypass (CPB) is associated with stroke and other adverse outcomes. Large and small arterial stenosis is prevalent in patients undergoing cardiac surgery. We hypothesize that large and/or small vessel cerebral arterial disease is associated with impaired cerebral autoregulation during CPB.

METHODS

A retrospective cohort analysis of data from 346 patients undergoing cardiac surgery with CPB enrolled in an ongoing prospectively randomized clinical trial of autoregulation monitoring were evaluated. The study protocol included preoperative transcranial Doppler (TCD) evaluation of major cerebral artery flow velocity by a trained vascular technician and brain magnetic resonance imaging (MRI) between postoperative days 3 and 5. Brain MRI images were evaluated for chronic white matter hyperintensities (WMHI) by a vascular neurologist blinded to autoregulation data. "Large vessel" cerebral vascular disease was defined by the presence of characteristic TCD changes associated with stenosis of the major cerebral arteries. "Small vessel" cerebral vascular disease was defined based on accepted scoring methods of WMHI. All patients had continuous TCD-based autoregulation monitoring during surgery.

RESULTS

Impaired autoregulation occurred in 32.4% (112/346) of patients. Preoperative TCD demonstrated moderate-severe large vessel stenosis in 67 (25.2%) of 266 patients with complete data. In adjusted analysis, female sex (odds ratio [OR], 0.46; 95% confidence interval [CI], 0.25-0.86; P = .014) and higher average temperature during CPB (OR, 1.23; 95% CI, 1.02-1.475; P = .029), but not moderate-severe large cerebral arterial stenosis (P = .406), were associated with impaired autoregulation during CPB. Of the 119 patients with available brain MRI data, 42 (35.3%) demonstrated WMHI. The presence of small vessel cerebral vascular disease was associated with impaired CBF autoregulation (OR, 3.25; 95% CI, 1.21-8.71; P = .019) after adjustment for age, history of peripheral vascular disease, preoperative hemoglobin level, and preoperative treatment with calcium channel blocking drugs.

CONCLUSIONS

These data confirm that impaired CBF autoregulation is prevalent during CPB predisposing affected patients to brain hypoperfusion or hyperperfusion with low or high blood pressure, respectively. Small vessel, but not large vessel, cerebral vascular disease, male sex, and higher average body temperature during CPB appear to be associated with impaired autoregulation.

Effect of Targeting Mean Arterial Pressure During Cardiopulmonary Bypass by Monitoring Cerebral Autoregulation on Postsurgical Delirium Among Older Patients: A Nested Randomized Clinical Trial

Importance

Delirium occurs in up to 52% of patients after cardiac surgery and may result from changes in cerebral perfusion. Using intraoperative cerebral autoregulation monitoring to individualize and optimize cerebral perfusion may be a useful strategy to reduce the incidence of delirium after cardiac surgery.

Objective

To determine whether targeting mean arterial pressure during cardiopulmonary bypass (CPB) using cerebral autoregulation monitoring reduces the incidence of delirium compared with usual care.

Design, Setting, and Participants

This randomized clinical trial nested within a larger trial enrolled patients older than 55 years who underwent nonemergency cardiac surgery at a single US academic medical center between October 11, 2012, and May 10, 2016, and had a high risk for neurologic complications. Patients, physicians, and outcome assessors were masked to the assigned intervention. A total of 2764 patients were screened, and 199 were eligible for analysis in this study.

Intervention

In the intervention group, the patient's lower limit of cerebral autoregulation was identified during surgery before CPB. On CPB, the patient's mean arterial pressure was targeted to be greater than that patient's lower limit of autoregulation. In the control group, mean arterial pressure targets were determined according to institutional practice.

Main Outcomes and Measures

The main outcome was any incidence of delirium on postoperative days 1 through 4, as adjudicated by a consensus expert panel.

Results

Among the 199 participants in this study, mean (SD) age was 70.3 (7.5) years and 150 (75.4%) were male. One hundred sixty-two (81.4%) were white, 26 (13.1%) were black, and 11 (5.5%) were of other race. Of 103 patients randomized to usual care, 94 were analyzed, and of 102 patients randomized to the intervention 105 were analyzed. Excluding 5 patients with coma, delirium occurred in 48 of the 91 patients (53%) in the usual care group compared with 39 of the 103 patients (38%) in the intervention group (P = .04). The odds of delirium were reduced by 45% in patients randomized to the autoregulation group (odds ratio, 0.55; 95% CI, 0.31-0.97; P = .04).

Conclusions and Relevance

The results of this study suggest that optimizing mean arterial pressure to be greater than the individual patient's lower limit of cerebral autoregulation during CPB may reduce the incidence of delirium after cardiac surgery, but further study is needed.

Trial Registration

ClinicalTrials.gov identifier: NCT00981474.

Association of Midlife Hypertension with Late-Life Hearing Loss

OBJECTIVE

To investigate the association of midlife hypertension with late-life hearing impairment.

STUDY DESIGN

Data from the Atherosclerosis Risk in Communities study, an ongoing prospective longitudinal population-based study (baseline, 1987-1989).

SETTING

Washington County, Maryland, research field site.

SUBJECTS AND METHODS

Subjects included 248 community-dwelling men and women aged 67 to 89 years in 2013. Systolic blood pressure (SBP) and diastolic blood pressure were measured at each of 5 study visits from 1987-1989 to 2013. Hypertension was defined by elevated systolic or diastolic blood pressure or antihypertensive medication use. A 4-frequency (0.5-4 kHz) better-hearing ear pure tone average in decibels hearing loss (dB HL) was calculated from pure tone audiometry measured in 2013. A cutoff of 40 dB HL was used to indicate clinically significant moderate to severe hearing impairment. Hearing thresholds at 5 frequencies (0.5-8 kHz) were also considered separately.

RESULTS

Forty-seven participants (19%) had hypertension at baseline (1987-1989), as opposed to 183 (74%) in 2013. The SBP association with late-life pure tone average differed by the time of measurement, with SBP measured at earlier visits associated with poorer hearing; the difference in pure tone average per 10-mm Hg SBP measured was 1.43 dB HL (95% CI, 0.32-2.53) at baseline versus -0.43 dB HL (95% CI, -1.41 to 0.55) in 2013. Baseline hypertension was associated with higher thresholds (poorer hearing) at 4 frequencies (1, 2, 4, 8 kHz).

CONCLUSION

Midlife SBP was associated with poorer hearing measured 25 years later. Further analysis into the longitudinal relationship between hypertension and hearing impairment is warranted.

Racial Differences in Prevalence and Risk for Intracranial Atherosclerosis in a US Community-Based Population

Importance

Intracranial atherosclerotic disease (ICAD) is an important cause of stroke; however, little is known about racial differences in ICAD prevalence and its risk factors.

Objective

To determine racial differences in ICAD prevalence and the risk factors (both midlife and concurrent) associated with its development in a large, US community-based cohort.

Design, Setting, and Participants

Analysis of 1752 black and white participants recruited from the Atherosclerosis Risk in Communities (ARIC) cohort study who underwent 3-dimensional intracranial vessel wall magnetic resonance imaging from October 18, 2011 to December 30, 2013; data analysis was performed from October 18, 2011 to May 13, 2015.

Exposures

Midlife and concurrent cardiovascular risk factors.

Main Outcomes and Measures

Intracranial plaque presence, size (maximum normalized wall index) and number were assessed by vessel wall magnetic resonance imaging. Midlife and concurrent vascular risk factor associations were determined by Poisson regression (plaque presence), negative binominal regression (plaque number), and linear regression (plaque size), and compared between races.

Results

Of the 1752 study participants (mean [SD] age, 77.6 [5.3] years; range, 67-90 years), 1023 (58.4%) were women and 518 (29.6%) were black. Black men had the highest prevalence (50.9% vs 35.9% for black women, 35.5% for white men, and 30.2% for white women; P < .001) and the highest frequency (22.4% vs 12.1% for black women, 10.7% for white men, and 8.7% for white women; P < .01) of multiple plaques. Prevalence increased with age, reaching 50% before ages 68, 84, and 88 years in black men, white men, and white women, respectively (ICAD prevalence remained <50% in black women). Midlife hypertension and hyperlipidemia were associated with 29% (prevalence ratio [PR], 1.29; 95% CI, 1.08-1.55) and 18% (PR, 1.18; 95% CI, 0.98-1.42), respectively, increased ICAD prevalence with no significant differences between races. Midlife hypertension was also associated with larger plaques (1.11 higher mean maximum normalized wall index; 95% CI, 0.21-2.01). Midlife smoking and diabetes were associated with increased risk of ICAD in black individuals (102% [PR, 2.02; 95% CI, 1.12-3.63] and 57% [PR, 1.57; 95% CI, 1.13- 2.19], respectively), but not in white participants (P < .05 interaction by race).

Conclusions and Relevance

The prevalence of ICAD was highest in black men. Midlife smoking and diabetes were strongly associated with late-life ICAD in blacks only, whereas midlife hypertension and hyperlipidemia were associated with late-life ICAD in both races. These associations may help to explain racial differences in US stroke rates and offer insight into preventive risk-factor management strategies.

Adherence to the Healthy Eating Index-2015 (HEI-2015), Cognitive Function, and Incident Dementia in the Atherosclerosis Risk in Communities (ARIC) Study (OR32-01-19)

Objectives

The Healthy Eating Index-2015 (HEI-2015) score was created to measure adherence to the 2015–2020 Dietary Guidelines for Americans. It remains undetermined whether adherence to the newly released guidelines is associated with improved cognitive function or reduced incident dementia.

Methods

We assessed the diet of 13,632 participants from the Atherosclerosis Risk in Communities (ARIC) study who were recruited from 1987–1989 and calculated their HEI-2015 scores (0–100) using responses to food frequency questionnaires. Baseline cognitive function was assessed using the Delayed Word Recall, Digit Symbol Substitution, and Word Fluency Tests. We used linear regression models to assess the cross-sectional association of adherence to HEI-2015 and standardized cognitive test scores. Incident dementia was ascertained through the end of 2017. Dementia status at the ARIC Neurocognitive Study visits (2011–13, 2016–17) was determined by detailed neurocognitive battery, informant interviews, and adjudicated review as well as through dementia screening by phone interview and informant review, or by ICD-9 dementia code for a hospitalization or death. We used Cox proportional hazards regression models adjusted for demographic, lifestyle, genetic, and clinical covariates to estimate the association between HEI-2015 score and risk of incident dementia.

Results

Compared to participants in the lowest quintile of HEI-2015 score, participants in the highest quintile scored higher on the Digit Symbol Substitution Test (β: 0.07, 95% CI: 0.03 to 0.11, P for trend < 0.001), Word Fluency Test (β: 0.07, 95% CI: 0.02 to 0.12, P for trend < 0.001) and global cognitive score (β: 0.05, 95% CI: 0.01 to 0.10, P for trend = 0.003) (Table). In total, there were 2354 cases of incident dementia over a median follow-up of 25 years. Compared to participants in the lowest quintile, participants in other quintiles had a lower risk of incident dementia after adjusting for covariates. Participants in the highest quintile had a 19% lower risk of dementia compared to those in the lowest (HR: 0.81, 95% CI: 0.71–0.93, P for trend = 0.01).

Conclusions

Higher adherence to the 2015–2020 Dietary Guidelines for Americans was associated with higher baseline cognitive function and lower risk of incident dementia.

Funding Sources

NHLBI, NIDDK, NIA, NINDS, NIH, HHS.

Supporting Tables, Images and/or Graphs

Plasma Metabolites Associated with Brain MRI Measures of Neurodegeneration in Older Adults in the Atherosclerosis Risk in Communities⁻Neurocognitive Study (ARIC-NCS)

Background: Plasma metabolites are associated with cognitive and physical function in the elderly. Because cerebral small vessel disease (SVD) and neurodegeneration are common causes of cognitive and physical function decline, the primary objective of this study was to investigate the associations of six plasma metabolites (two plasma phosphatidylcholines [PCs]: PC aa C36:5 and PC aa 36:6 and four sphingomyelins [SMs]: SM C26:0, SM [OH] C22:1, SM [OH] C22:2, SM [OH] C24:1) with magnetic resonance imaging (MRI) features of cerebral SVD and neurodegeneration in older adults. Methods: This study included 238 older adults in the Atherosclerosis Risk in Communities study at the fifth exam. Multiple linear regression was used to assess the association of each metabolite (log-transformed) in separate models with MRI measures except lacunar infarcts, for which binary logistic regression was used. Results: Higher concentrations of plasma PC aa C36:5 had adverse associations with MRI features of cerebral SVD (odds ratio of 1.69 [95% confidence interval: 1.01, 2.83] with lacunar infarct, and beta of 0.16 log [cm3] [0.02, 0.30] with log [White Matter Hyperintensities (WMH) volume]) while higher concentrations of 3 plasma SM (OH)s were associated with higher total brain volume (beta of 12.0 cm3 [5.5, 18.6], 11.8 cm3 [5.0, 18.6], and 7.3 cm3 [1.2, 13.5] for SM [OH] C22:1, SM [OH] C22:2, and SM [OH] C24:1, respectively). Conclusions: This study identified associations between certain plasma metabolites and brain MRI measures of SVD and neurodegeneration in older adults, particularly higher SM (OH) concentrations with higher total brain volume.

Abstract TP157: Ethnic Difference in Stroke Recurrence for Patients With Intracranial Atherosclerotic Stenosis

Background: Intracranial atherosclerotic stenosis (ICAS), one of most common stroke subtypes worldwide, carries high risk of stroke recurrence despite maximal medical treatment. ICAS more commonly affects non-white populations including Asian, African-American and Hispanic individuals. It is plausible that non-white stroke patients with ICAS might also have more active disease, and thus higher risks of stroke recurrence. We aim to compare the rate of stroke recurrence in stroke patients with ICAS in white and non-white population. Method: We retrospectively reviewed a consecutive series of patients with ischemic stroke due to ICAS in major vessels (MCA, ACA, PCA, intracranial segment of ICA and VA, BA) with >50% stenosis identified on MRA or CTA. The clinical characteristics, risk factors and rate of stroke recurrence were compared in white and non-white patients, using Chi-square (for categorical variables) test and t-test (for continuous variables).

Results: A total of 183 patients [66.3% non-white, mean (SD) age, 63 (±14) years] who were hospitalized between January 2005 and December 2010 and satisfied the inclusion criteria were included in the analysis. Compared with white patients, non-white patients had a higher rate of HTN, DM and drug abuse (Table 1), as well a nonsignificantly higher stroke recurrence rate (3 months: OR 1.29, 95% CI 0.59-2.82; long term: OR 1.63, 95% CI 0.84 - 3.18). History of CKD was the only factor associated with 3-month stroke recurrence (OR 3.73, 965 CI 1.13-12.31).

Conclusion: White and non-white ischemic stroke patients with ICAS have distinct risk factor profiles and possibly distinct stroke recurrence rates. Analysis with a larger sample size is ongoing to verify this finding.