Genetic variants for head size share genes and pathways with cancer

The size of the human head is highly heritable, but genetic drivers of its variation within the general population remain unmapped. We perform a genome-wide association study on head size (N = 80,890) and identify 67 genetic loci, of which 50 are novel. Neuroimaging studies show that 17 variants affect specific brain areas, but most have widespread effects. Gene set enrichment is observed for various cancers and the p53, Wnt, and ErbB signaling pathways. Genes harboring lead variants are enriched for macrocephaly syndrome genes (37-fold) and high-fidelity cancer genes (9-fold), which is not seen for human height variants. Head size variants are also near genes preferentially expressed in intermediate progenitor cells, neural cells linked to evolutionary brain expansion. Our results indicate that genes regulating early brain and cranial growth incline to neoplasia later in life, irrespective of height. This warrants investigation of clinical implications of the link between head size and cancer.

Cumulative Systolic Blood Pressure and Incident Stroke Type Variation by Race and Ethnicity

Importance

Stroke risk varies by systolic blood pressure (SBP), race, and ethnicity. The association between cumulative mean SBP and incident stroke type is unclear, and whether this association differs by race and ethnicity remains unknown.

Objective

To examine the association between cumulative mean SBP and first incident stroke among 3 major stroke types-ischemic stroke (IS), intracerebral hemorrhage (ICH), and subarachnoid hemorrhage (SAH)-and explore how these associations vary by race and ethnicity.

Design, Setting, and Participants

Individual participant data from 6 US longitudinal cohorts (January 1, 1971, to December 31, 2019) were pooled. The analysis was performed from January 1, 2022, to January 2, 2024. The median follow-up was 21.6 (IQR, 13.6-31.8) years.

Exposure

Time-dependent cumulative mean SBP.

Main Outcomes and Measures

The primary outcome was time from baseline visit to first incident stroke. Secondary outcomes consisted of time to first incident IS, ICH, and SAH.

Results

Among 40 016 participants, 38 167 who were 18 years or older at baseline with no history of stroke and at least 1 SBP measurement before the first incident stroke were included in the analysis. Of these, 54.0% were women; 25.0% were Black, 8.9% were Hispanic of any race, and 66.2% were White. The mean (SD) age at baseline was 53.4 (17.0) years and the mean (SD) SBP at baseline was 136.9 (20.4) mm Hg. A 10-mm Hg higher cumulative mean SBP was associated with a higher risk of overall stroke (hazard ratio [HR], 1.20 [95% CI, 1.18-1.23]), IS (HR, 1.20 [95% CI, 1.17-1.22]), and ICH (HR, 1.31 [95% CI, 1.25-1.38]) but not SAH (HR, 1.13 [95% CI, 0.99-1.29]; P = .06). Compared with White participants, Black participants had a higher risk of IS (HR, 1.20 [95% CI, 1.09-1.33]) and ICH (HR, 1.67 [95% CI, 1.30-2.13]) and Hispanic participants of any race had a higher risk of SAH (HR, 3.81 [95% CI, 1.29-11.22]). There was no consistent evidence that race and ethnicity modified the association of cumulative mean SBP with first incident stroke and stroke type.

Conclusions and Relevance

The findings of this cohort study suggest that cumulative mean SBP was associated with incident stroke type, but the associations did not differ by race and ethnicity. Culturally informed stroke prevention programs should address modifiable risk factors such as SBP along with social determinants of health and structural inequities in society.

Incidence of Stroke in Indigenous Populations of Countries With a Very High Human Development Index: A Systematic Review

BACKGROUND AND OBJECTIVES

Cardiovascular disease contributes significantly to disease burden among many Indigenous populations. However, data on stroke incidence in Indigenous populations are sparse. We aimed to investigate what is known of stroke incidence in Indigenous populations of countries with a very high Human Development Index (HDI), locating the research in the broader context of Indigenous health.

METHODS

We identified population-based stroke incidence studies published between 1990 and 2022 among Indigenous adult populations of developed countries using PubMed, Embase, and Global Health databases, without language restriction. We excluded non-peer-reviewed sources, studies with fewer than 10 Indigenous people, or not covering a 35- to 64-year minimum age range. Two reviewers independently screened titles, abstracts, and full-text articles and extracted data. We assessed quality using "gold standard" criteria for population-based stroke incidence studies, the Newcastle-Ottawa Scale for risk of bias, and CONSIDER criteria for reporting of Indigenous health research. An Indigenous Advisory Board provided oversight for the study.

RESULTS

From 13,041 publications screened, 24 studies (19 full-text articles, 5 abstracts) from 7 countries met the inclusion criteria. Age-standardized stroke incidence rate ratios were greater in Aboriginal and Torres Strait Islander Australians (1.7-3.2), American Indians (1.2), Sámi of Sweden/Norway (1.08-2.14), and Singaporean Malay (1.7-1.9), compared with respective non-Indigenous populations. Studies had substantial heterogeneity in design and risk of bias. Attack rates, male-female rate ratios, and time trends are reported where available. Few investigators reported Indigenous stakeholder involvement, with few studies meeting any of the CONSIDER criteria for research among Indigenous populations.

DISCUSSION

In countries with a very high HDI, there are notable, albeit varying, disparities in stroke incidence between Indigenous and non-Indigenous populations, although there are gaps in data availability and quality. A greater understanding of stroke incidence is imperative for informing effective societal responses to socioeconomic and health disparities in these populations. Future studies into stroke incidence in Indigenous populations should be designed and conducted with Indigenous oversight and governance to facilitate improved outcomes and capacity building.

REGISTRATION INFORMATION

PROSPERO registration: CRD42021242367.

Plasma biomarkers of Alzheimer's disease and related dementias in American Indians: The Strong Heart Study

INTRODUCTION

Identification of Alzheimer's disease (AD) needs inexpensive, noninvasive biomarkers, with validation in all populations.

METHODS

We collected plasma markers in older American Indian individuals: phosphorylated-tau181 (pTau181); amyloid-beta (Aβ) 40,42; glial fibrillary acidic protein (GFAP); and neurofilament light chain (NfL). Plasma markers were analyzed for discriminant properties with cognitive status and etiology using receiver operating characteristic (ROC) analysis.

RESULTS

PTau181, GFAP, NfL plasma values were significantly associated with cognition, but Aβ were not. Discriminant performance was moderate for individual markers, with pTau181, GFAP, NfL performing best, but an empirically selected panel of markers (age, sex, education, pTau181, GFAP, NfL, Aβ4240 ratio) had excellent discriminant performance (AUC > 0.8).

DISCUSSION

In American Indian individuals, pTau181 and Aβ values suggested more common pathology than in majority populations. Aβ was less informative than in other populations; however, all four markers were needed for a best-performing dementia diagnostic model. These data validate utility of AD plasma markers, while suggesting population-specific diagnostic characteristics.

Apixaban to Prevent Recurrence After Cryptogenic Stroke in Patients With Atrial Cardiopathy: The ARCADIA Randomized Clinical Trial

Importance

Atrial cardiopathy is associated with stroke in the absence of clinically apparent atrial fibrillation. It is unknown whether anticoagulation, which has proven benefit in atrial fibrillation, prevents stroke in patients with atrial cardiopathy and no atrial fibrillation.

Objective

To compare anticoagulation vs antiplatelet therapy for secondary stroke prevention in patients with cryptogenic stroke and evidence of atrial cardiopathy.

Design, Setting, and Participants

Multicenter, double-blind, phase 3 randomized clinical trial of 1015 participants with cryptogenic stroke and evidence of atrial cardiopathy, defined as P-wave terminal force greater than 5000 μV × ms in electrocardiogram lead V1, serum N-terminal pro-B-type natriuretic peptide level greater than 250 pg/mL, or left atrial diameter index of 3 cm/m2 or greater on echocardiogram. Participants had no evidence of atrial fibrillation at the time of randomization. Enrollment and follow-up occurred from February 1, 2018, through February 28, 2023, at 185 sites in the National Institutes of Health StrokeNet and the Canadian Stroke Consortium.

Interventions

Apixaban, 5 mg or 2.5 mg, twice daily (n = 507) vs aspirin, 81 mg, once daily (n = 508).

Main Outcomes and Measures

The primary efficacy outcome in a time-to-event analysis was recurrent stroke. All participants, including those diagnosed with atrial fibrillation after randomization, were analyzed according to the groups to which they were randomized. The primary safety outcomes were symptomatic intracranial hemorrhage and other major hemorrhage.

Results

With 1015 of the target 1100 participants enrolled and mean follow-up of 1.8 years, the trial was stopped for futility after a planned interim analysis. The mean (SD) age of participants was 68.0 (11.0) years, 54.3% were female, and 87.5% completed the full duration of follow-up. Recurrent stroke occurred in 40 patients in the apixaban group (annualized rate, 4.4%) and 40 patients in the aspirin group (annualized rate, 4.4%) (hazard ratio, 1.00 [95% CI, 0.64-1.55]). Symptomatic intracranial hemorrhage occurred in 0 patients taking apixaban and 7 patients taking aspirin (annualized rate, 1.1%). Other major hemorrhages occurred in 5 patients taking apixaban (annualized rate, 0.7%) and 5 patients taking aspirin (annualized rate, 0.8%) (hazard ratio, 1.02 [95% CI, 0.29-3.52]).

Conclusions and Relevance

In patients with cryptogenic stroke and evidence of atrial cardiopathy without atrial fibrillation, apixaban did not significantly reduce recurrent stroke risk compared with aspirin.

Trial Registration

ClinicalTrials.gov Identifier: NCT03192215.

The Association of Upper Airway Anatomy with Brain Structure: The Multi-Ethnic Study of Atherosclerosis

Sleep apnea, affecting an estimated 1 in 4 American adults, has been reported to be associated with both brain structural abnormality and impaired cognitive function. Obstructive sleep apnea is known to be affected by upper airway anatomy. To better understand the contribution of upper airway anatomy to pathways linking sleep apnea with impaired cognitive function, we investigated the association of upper airway anatomy with structural brain abnormalities. Based in the Multi-Ethnic Study of Atherosclerosis, a longitudinal cohort study of community-dwelling adults, a comprehensive sleep study and an MRI of the upper airway and brain were performed on 578 participants. Machine learning models were used to select from 74 upper airway measures those measures most associated with selected regional brain volumes and white matter hyperintensity volume. Linear regression assessed associations between the selected upper airway measures, sleep measures, and brain structure. Maxillary divergence was positively associated with hippocampus volume, and mandible length was negatively associated with total white and gray matter volume. Both coefficients were small (coefficients per standard deviation 0.063 mL, p = 0.04, and - 7.0 mL, p < 0.001 respectively), and not affected by adjustment for sleep study measures. Self-reported snoring >2 times per week was associated with larger hippocampus volume (coefficient 0.164 mL, p = 0.007), and higher percentage of time in the N3 sleep stage was associated with larger total white and gray matter volume (4.8 mL, p = 0.004). Despite associations of two upper airway anatomy measures with brain volume, the evidence did not suggest that these upper airway and brain structure associations were acting primarily through the pathway of sleep disturbance.

Serum NfL and GFAP are associated with incident dementia and dementia mortality in older adults: The cardiovascular health study

INTRODUCTION

Circulating neurofilament light chain (NfL) and glial fibrillary acidic protein (GFAP) have been independently associated with dementia risk. Their additive association, and their associations with dementia-specific mortality, have not been investigated.

METHODS

We associated serum NfL, GFAP, total tau ,and ubiquitin carboxyl-terminal hydrolase-L1, measured in 1712 dementia-free adults, with 19-year incident dementia and dementia-specific mortality risk, and with 3-year cognitive decline.

RESULTS

In adjusted models, being in the highest versus lowest tertile of NfL or GFAP associated with a hazard ratio (HR) of 1.49 (1.20-1.84) and 1.38 (1.15-1.66) for incident dementia, and 2.87 (1.79-4.61) and 2.76 (1.73-4.40) for dementia-specific mortality. Joint third versus first tertile exposure further increased risk; HR = 2.06 (1.60-2.67) and 9.22 (4.48-18.9). NfL was independently associated with accelerated cognitive decline.

DISCUSSION

Circulating NfL and GFAP may, independently and jointly, provide useful clinical insight regarding dementia risk and prognosis.

The association of upper airway anatomy with cognitive test performance: the Multi-Ethnic Study of Atherosclerosis

BACKGROUND

Numerous upper airway anatomy characteristics are risk factors for sleep apnea, which affects 26% of older Americans, and more severe sleep apnea is associated with cognitive impairment. This study explores the pathophysiology and links between upper airway anatomy, sleep, and cognition.

METHODS

Participants in the Multi-Ethnic Study of Atherosclerosis underwent an upper airway MRI, polysomnography to assess sleep measures including the apnea-hypopnea index (AHI) and completed the Cognitive Abilities Screening Instrument (CASI). Two model selection techniques selected from among 67 upper airway measures those that are most strongly associated with CASI score. The associations of selected upper airway measures with AHI, AHI with CASI score, and selected upper airway anatomy measures with CASI score, both alone and after adjustment for AHI, were assessed using linear regression.

RESULTS

Soft palate volume, maxillary divergence, and upper facial height were significantly positively associated with higher CASI score, indicating better cognition. The coefficients were small, with a 1 standard deviation (SD) increase in these variables being associated with a 0.83, 0.75, and 0.70 point higher CASI score, respectively. Additional adjustment for AHI very slightly attenuated these associations. Larger soft palate volume was significantly associated with higher AHI (15% higher AHI (95% CI 2%,28%) per SD). Higher AHI was marginally associated with higher CASI score (0.43 (95% CI 0.01,0.85) per AHI doubling).

CONCLUSIONS

Three upper airway measures were weakly but significantly associated with higher global cognitive test performance. Sleep apnea did not appear to be the mechanism through which these upper airway and cognition associations were acting. Further research on the selected upper airway measures is recommended.

Neighborhood greenspace and neighborhood income associated with white matter grade worsening: Cardiovascular Health Study

INTRODUCTION

We examined whether a combined measure of neighborhood greenspace and neighborhood median income was associated with white matter hyperintensity (WMH) and ventricle size changes.

METHODS

The sample included 1260 cognitively normal ≥ 65-year-olds with two magnetic resonance images (MRI; ≈ 5 years apart). WMH and ventricular size were graded from 0 (least) to 9 (most) abnormal (worsening = increase of ≥1 grade from initial to follow-up MRI scans). The four-category neighborhood greenspace-income measure was based on median neighborhood greenspace and income values at initial MRI. Multivariable logistic regression tested associations between neighborhood greenspace-income and MRI measures (worsening vs. not).

RESULTS

White matter grade worsening was more likely for those in lower greenspace-lower income neighborhoods than higher greenspace-higher income neighborhoods (odds ratio = 1.73; 95% confidence interval = 1.19-2.51).

DISCUSSION

The combination of lower neighborhood income and lower greenspace may be a risk factor for worsening white matter grade on MRI. However, findings need to be replicated in more diverse cohorts.

HIGHLIGHTS

Population-based cohort of older adults (≥ 65 years) with greenspace and MRI dataCombined measure of neighborhood greenspace and neighborhood income at initial MRIMRI outcomes included white matter hyperintensities (WMH) and ventricular sizeLongitudinal change in MRI outcomes measured approximately 5 years apartWorsening WMH over time more likely for lower greenspace-lower income neighborhoods.

Body Mass Index, White Matter Hyperintensities, and Cognitive Performance in American Indians: Data from the Strong Heart Study

BACKGROUND

Previous studies report that obesity can be a risk and a protective factor for cognitive health. However, they have not examined whether white matter hyperintensities (WMH) mediate the association between mid- or late-life body mass index (BMI) and late-life cognitive performance. We examined this question in American Indians, a population underrepresented in neuropsychological research.

METHOD

We used longitudinal data from the cerebrovascular disease and its consequences in American Indians (n = 817), with BMI data collected at midlife (1989-91) and lat-life (2010-13). Cognitive data were collected in late life, with tests for general cognition, processing speed, verbal fluency, and memory. Neuroradiologist-scored WMH severity and volume using standard analysis pipelines. We examined associations among BMI, WMH severity and volume, and cognitive scores using linear regression and the Baron and Kenny method to estimate mediation.

RESULT

High BMI in late life was associated with a 1.79-point higher score in general cognition (95% CI 0.63-2.95, p-value = 0.002), but not the other tests. Mediated by WMH severity, high late-life BMI was associated with a 1.53-point higher score in general cognition (95% CI 0.37-2.69) and, by WMH volume, 1.63 points higher (95% CI 0.49-2.77). The association between late-life obesity and cognitive performance is stronger for females (β = 1.74, 95% CI 0.35-3.13, p-value = 0.014) than for males (β = 1.66, 95% CI -0.63-3.95, p-value = 0.158).

CONCLUSION

In American Indians, high late-life BMI was positively associated with cognitive performance, with a stronger association for females. WMH severity and volume partly attenuate these associations.

Association of brain microbleeds with risk factors, cognition, and MRI markers in MESA

INTRODUCTION

Little is known about the epidemiology of brain microbleeds in racially/ethnically diverse populations.

METHODS

In the Multi-Ethnic Study of Atherosclerosis, brain microbleeds were identified from 3T magnetic resonance imaging susceptibility-weighted imaging sequences using deep learning models followed by radiologist review.

RESULTS

Among 1016 participants without prior stroke (25% Black, 15% Chinese, 19% Hispanic, 41% White, mean age 72), microbleed prevalence was 20% at age 60 to 64.9 and 45% at ≥85 years. Deep microbleeds were associated with older age, hypertension, higher body mass index, and atrial fibrillation, and lobar microbleeds with male sex and atrial fibrillation. Overall, microbleeds were associated with greater white matter hyperintensity volume and lower total white matter fractional anisotropy.

DISCUSSION

Results suggest differing associations for lobar versus deep locations. Sensitive microbleed quantification will facilitate future longitudinal studies of their potential role as an early indicator of vascular pathology.

Carriers of rare damaging CCR2 genetic variants are at lower risk of atherosclerotic disease

Background

The CCL2/CCR2 axis governs monocyte trafficking and recruitment to atherosclerotic lesions. Human genetic analyses and population-based studies support an association between circulating CCL2 levels and atherosclerosis. Still, it remains unknown whether pharmacological targeting of CCR2, the main CCL2 receptor, would provide protection against human atherosclerotic disease.

Methods

In whole-exome sequencing data from 454,775 UK Biobank participants (40-69 years), we identified predicted loss-of-function (LoF) or damaging missense (REVEL score >0.5) variants within the CCR2 gene. We prioritized variants associated with lower monocyte count (p<0.05) and tested associations with vascular risk factors and risk of atherosclerotic disease over a mean follow-up of 14 years. The results were replicated in a pooled cohort of three independent datasets (TOPMed, deCODE and Penn Medicine BioBank; total n=441,445) and the effect of the most frequent damaging variant was experimentally validated.

Results

A total of 45 predicted LoF or damaging missense variants were identified in the CCR2 gene, 4 of which were also significantly associated with lower monocyte count, but not with other white blood cell counts. Heterozygous carriers of these variants were at a lower risk of a combined atherosclerosis outcome, showed a lower burden of atherosclerosis across four vascular beds, and were at a lower lifetime risk of coronary artery disease and myocardial infarction. There was no evidence of association with vascular risk factors including LDL-cholesterol, blood pressure, glycemic status, or C-reactive protein. Using a cAMP assay, we found that cells transfected with the most frequent CCR2 damaging variant (3:46358273:T:A, M249K, 547 carriers, frequency: 0.14%) show a decrease in signaling in response to CCL2. The associations of the M249K variant with myocardial infarction were consistent across cohorts (ORUKB: 0.62 95%CI: 0.39-0.96; ORexternal: 0.64 95%CI: 0.34-1.19; ORpooled: 0.64 95%CI: 0.450.90). In a phenome-wide association study, we found no evidence for higher risk of common infections or mortality among carriers of damaging CCR2 variants.

Conclusions

Heterozygous carriers of damaging CCR2 variants have a lower burden of atherosclerosis and lower lifetime risk of myocardial infarction. In conjunction with previous evidence from experimental and epidemiological studies, our findings highlight the translational potential of CCR2-targeting as an atheroprotective approach.

Plasma Trimethylamine-N-Oxide and Incident Ischemic Stroke: The Cardiovascular Health Study and the Multi-Ethnic Study of Atherosclerosis

Background The association of circulating trimethylamine-N-oxide (TMAO) with stroke has received limited attention. To address this gap, we examined the associations of serial measures of plasma TMAO with incident ischemic stroke. Methods and Results We used a prospective cohort design with data pooled from 2 cohorts. The settings were the CHS (Cardiovascular Health Study), a cohort of older adults, and the MESA (Multi-Ethnic Study of Atherosclerosis), both in the United States. We measured plasma concentrations of TMAO at baseline and again during the follow-up using high-performance liquid chromatography and mass spectrometry. We assessed the association of plasma TMAO with incident ischemic stroke using proportional hazards regression adjusted for risk factors. The combined cohorts included 11 785 participants without a history of stroke, on average 73 (CHS) and 62 (MESA) years old at baseline, including 60% (CHS) and 53% (MESA) women. We identified 1031 total incident ischemic strokes during a median 15-year follow-up in the combined cohorts. In multivariable analyses, TMAO was significantly associated with incident ischemic stroke risk (hazard ratios comparing a doubling of TMAO: 1.11 [1.03-1.18], P=0.004). The association was linear over the range of TMAO concentrations and appeared restricted to those without diagnosed coronary heart disease. An association with hemorrhagic stroke was not found. Conclusions Plasma TMAO levels are associated with incident ischemic stroke in a diverse population. Registration URL: https://www.clinicaltrials.gov. Unique identifier: NCT00005133.

Complexities of cerebral small vessel disease, blood pressure, and dementia relationship: new insights from genetics

Importance

There is increasing recognition that vascular disease, which can be treated, is a key contributor to dementia risk. However, the contribution of specific markers of vascular disease is unclear and, as a consequence, optimal prevention strategies remain unclear.

Objective

To disentangle the causal relation of several key vascular traits to dementia risk: (i) white matter hyperintensity (WMH) burden, a highly prevalent imaging marker of covert cerebral small vessel disease (cSVD); (ii) clinical stroke; and (iii) blood pressure (BP), the leading risk factor for cSVD and stroke, for which efficient therapies exist. To account for potential epidemiological biases inherent to late-onset conditions like dementia.

Design Setting and Participants

This study first explored the association of genetically determined WMH, BP levels and stroke risk with AD using summary-level data from large genome-wide association studies (GWASs) in a two-sample Mendelian randomization (MR) framework. Second, leveraging individual-level data from large longitudinal population-based cohorts and biobanks with prospective dementia surveillance, the association of weighted genetic risk scores (wGRSs) for WMH, BP, and stroke with incident all-cause-dementia was explored using Cox-proportional hazard and multi-state models. The data analysis was performed from July 26, 2020, through July 24, 2022.

Exposures

Genetically determined levels of WMH volume and BP (systolic, diastolic and pulse blood pressures) and genetic liability to stroke.

Main outcomes and measures

The summary-level MR analyses focused on the outcomes from GWAS of clinically diagnosed AD (n-cases=21,982) and GWAS additionally including self-reported parental history of dementia as a proxy for AD diagnosis (ADmeta, n-cases=53,042). For the longitudinal analyses, individual-level data of 157,698 participants with 10,699 incident all-cause-dementia were studied, exploring AD, vascular or mixed dementia in secondary analyses.

Results

In the two-sample MR analyses, WMH showed strong evidence for a causal association with increased risk of ADmeta (OR, 1.16; 95%CI:1.05-1.28; P=.003) and AD (OR, 1.28; 95%CI:1.07-1.53; P=.008), after accounting for genetically determined pulse pressure for the latter. Genetically predicted BP traits showed evidence for a protective association with both clinically defined AD and ADmeta, with evidence for confounding by shared genetic instruments. In longitudinal analyses the wGRSs for WMH, but not BP or stroke, showed suggestive association with incident all-cause-dementia (HR, 1.02; 95%CI:1.00-1.04; P=.06). BP and stroke wGRSs were strongly associated with mortality but there was no evidence for selective survival bias during follow-up. In secondary analyses, polygenic scores with more liberal instrument definition showed association of both WMH and stroke with all-cause-dementia, AD, and vascular or mixed dementia; associations of stroke, but not WMH, with dementia outcomes were markedly attenuated after adjusting for interim stroke.

Conclusion

These findings provide converging evidence that WMH is a leading vascular contributor to dementia risk, which may better capture the brain damage caused by BP (and other etiologies) than BP itself and should be targeted in priority for dementia prevention in the population.

Plasma Proteomic Associations With Incident Ischemic Stroke in Older Adults: The Cardiovascular Health Study

BACKGROUND

Plasma proteomics may elucidate novel insights into the pathophysiology of ischemic stroke (IS), identify biomarkers of IS risk, and guide development of nascent prevention strategies. We evaluated the relationship between the plasma proteome and IS risk in the population-based Cardiovascular Health Study (CHS).

METHODS

Eligible CHS participants were free of prevalent stroke and underwent quantification of 1298 plasma proteins using the aptamer-based SOMAScan assay platform from the 1992-1993 study visit. Multivariable Cox proportional hazards regression was used to evaluate associations between a 1-standard deviation increase in the log-2 transformed estimated plasma protein concentrations and incident IS, adjusting for demographics, IS risk factors, and estimated glomerular filtration rate. For proteins independently associated with incident IS, a secondary stratified analysis evaluated associations in subgroups defined by sex and race. Exploratory analyses evaluated plasma proteomic associations with cardioembolic and non-cardioembolic IS as well as proteins associated with IS risk in participants with left atrial dysfunction but without atrial fibrillation.

RESULTS

Of 2983 eligible participants, the mean age was 74.3 (± 4.8) years, 61.2% were women, and 15.4% were Black. Over a median follow-up of 12.6 years, 450 participants experienced an incident IS. N-terminal pro-brain natriuretic peptide (NTproBNP, adjusted HR 1.37, 95% CI 1.23-1.53, P=2.08x10^-08) and macrophage metalloelastase (MMP12, adjusted HR 1.30, 95% CI 1.16-1.45, P=4.55x10^-06) were independently associated with IS risk. These two associations were similar in men and women and in Black and non-Black participants. In exploratory analyses, NTproBNP was independently associated with incident cardioembolic IS, E-selectin with incident non-cardioembolic IS, and secreted frizzled-related protein 1 with IS risk in participants with left atrial dysfunction.

CONCLUSIONS

In a cohort of older adults, NTproBNP and MMP12 were independently associated with IS risk. We identified plasma proteomic determinants of incident cardioembolic and non-cardioembolic IS and found a novel protein associated with IS risk in those with left atrial dysfunction.

Identification of Palliative Care Needs and Mental Health Outcomes Among Family Members of Patients With Severe Acute Brain Injury

Importance

Family members of patients with severe acute brain injury (SABI) are at risk for poor psychological outcomes.

Objective

To explore the utility of the early use of a palliative care needs checklist in identifying care needs of patients with SABI and family members who are at risk of poor psychological outcomes.

Design, Setting, and Participants

This prospective cohort study included patients with SABI in an intensive care unit (ICU) for 2 days or more and a Glasgow Coma Scale score of 12 or lower and their family members. This single-center study was conducted at an academic hospital in Seattle, Washington, from January 2018 to June 2021. Data were analyzed from July 2021 to July 2022.

Exposure

At enrollment, a 4-item palliative care needs checklist was completed separately by clinicians and family members.

Main Outcomes and Measures

A single family member for each enrolled patient completed questionnaires assessing symptoms of depression and anxiety, perception of goal-concordant care, and satisfaction in the ICU. Six months later, family members assessed their psychological symptoms, decisional regret, patient functional outcome, and patient quality of life (QOL).

Results

A total of 209 patient-family member pairs (family member mean [SD] age, 51 [16] years; 133 women [64%]; 18 Asian [9%], 21 Black [10%], 20 [10%] Hispanic, and 153 White [73%] participants) were included. Patients had experienced stroke (126 [60%]), traumatic brain injury (62 [30%]), and hypoxic-ischemic encephalopathy (21 [10%]). At least 1 need was identified for 185 patients or their families (88%) by family members and 110 (53%) by clinicians (κ = -0.007; 52% agreement). Symptoms of at least moderate anxiety or depression were present in 50% of family members at enrollment (87 with anxiety and 94 with depression) and 20% at follow-up (33 with anxiety and 29 with depression). After adjustment for patient age, diagnosis, and disease severity and family race and ethnicity, clinician identification of any need was associated with greater goal discordance (203 participants; relative risk = 1.7 [95% CI, 1.2 to 2.5]) and family decisional regret (144 participants; difference in means, 17 [95% CI, 5 to 29] points). Family member identification of any need was associated with greater symptoms of depression at follow-up (150 participants; difference in means of Patient Health Questionnaire-2, 0.8 [95% CI, 0.2 to 1.3] points) and worse perceived patient QOL (78 participants; difference in means, -17.1 [95% CI, -33.6 to -0.5] points).

Conclusions and Relevance

In this prospective cohort study of patients with SABI and their families, palliative care needs were common, although agreement on needs was poor between clinicians and family members. A palliative care needs checklist completed by clinicians and family members may improve communication and promote timely, targeted management of needs.

Epigenetic and integrative cross-omics analyses of cerebral white matter hyperintensities on MRI

Cerebral white matter hyperintensities on MRI are markers of cerebral small vessel disease, a major risk factor for dementia and stroke. Despite the successful identification of multiple genetic variants associated with this highly heritable condition, its genetic architecture remains incompletely understood. More specifically, the role of DNA methylation has received little attention. We investigated the association between white matter hyperintensity burden and DNA methylation in blood at ∼450 000 cytosine-phosphate-guanine (CpG) sites in 9732 middle-aged to older adults from 14 community-based studies. Single CpG and region-based association analyses were carried out. Functional annotation and integrative cross-omics analyses were performed to identify novel genes underlying the relationship between DNA methylation and white matter hyperintensities. We identified 12 single CpG and 46 region-based DNA methylation associations with white matter hyperintensity burden. Our top discovery single CpG, cg24202936 (P = 7.6 × 10-8), was associated with F2 expression in blood (P = 6.4 × 10-5) and co-localized with FOLH1 expression in brain (posterior probability = 0.75). Our top differentially methylated regions were in PRMT1 and in CCDC144NL-AS1, which were also represented in single CpG associations (cg17417856 and cg06809326, respectively). Through Mendelian randomization analyses cg06809326 was putatively associated with white matter hyperintensity burden (P = 0.03) and expression of CCDC144NL-AS1 possibly mediated this association. Differentially methylated region analysis, joint epigenetic association analysis and multi-omics co-localization analysis consistently identified a role of DNA methylation near SH3PXD2A, a locus previously identified in genome-wide association studies of white matter hyperintensities. Gene set enrichment analyses revealed functions of the identified DNA methylation loci in the blood-brain barrier and in the immune response. Integrative cross-omics analysis identified 19 key regulatory genes in two networks related to extracellular matrix organization, and lipid and lipoprotein metabolism. A drug-repositioning analysis indicated antihyperlipidaemic agents, more specifically peroxisome proliferator-activated receptor-alpha, as possible target drugs for white matter hyperintensities. Our epigenome-wide association study and integrative cross-omics analyses implicate novel genes influencing white matter hyperintensity burden, which converged on pathways related to the immune response and to a compromised blood-brain barrier possibly due to disrupted cell-cell and cell-extracellular matrix interactions. The results also suggest that antihyperlipidaemic therapy may contribute to lowering risk for white matter hyperintensities possibly through protection against blood-brain barrier disruption.

Abstract 140: The Incidence Of Stroke In Indigenous Populations Of Countries With A Very High Human Development Index: A Systematic Review

Introduction: Despite known socioeconomic and health disparities affecting Indigenous populations in developed countries, stroke incidence data are sparse. With Indigenous Advisory Board oversight, we undertook a systematic review to compare Indigenous with non-Indigenous stroke incidence rates in countries with a very high Human Development Index (HDI).

Methods: We identified population-based stroke incidence studies published from 1990-2022 in Indigenous adult populations of developed countries using PubMed, EMBASE and Global Health databases, without language restriction. We excluded non-peer-reviewed sources, studies with <10 Indigenous people, or studies not covering a 35-64 year minimum age range. Two reviewers independently screened titles, abstracts, and full texts, and extracted data. We assessed quality using "ideal" criteria for population-based stroke incidence studies, the Newcastle-Ottawa Scale for risk of bias, and CONSIDER criteria for Indigenous research.

Results: Among 13,041 publications, 24 studies (19 full text, 5 abstracts) from 7 countries met inclusion criteria. Compared with respective non-Indigenous populations (Fig 1), age-standardised incidence rates were greater in Aboriginal and Torres Strait Islander Australians (ratios ranging from 1.7-3.2), American Indians (1.2), Sámi of Sweden/Norway (1.08-2.14), and Singaporean Malay (1.7-1.9), with higher rate ratios at younger ages. Studies had substantial heterogeneity in design and risk of bias. Few investigators reported Indigenous stakeholder involvement.

Conclusions: In countries with a very high HDI, available data suggest marked disparities in stroke incidence in Indigenous populations, although there are gaps in data availability and quality. Indigenous stakeholder involvement in studies is infrequently reported. A greater understanding of stroke incidence in these populations is imperative for informing effective societal responses.

Sleep Health as a Determinant of Disparities in Stroke Risk and Health Outcome

Sleep is essential to human survival and overall vascular health. Sleep health encompasses the objective and subjective qualities associated with one's daily pattern of sleep and wakefulness and has become a growing clinical and public health concern. Impaired sleep duration and quality can increase stroke risk and mediate the relationship between the physical aspects of an individual's environment and disparities in stroke incidence. Here, we review observational studies evaluating the association between sleep health and cerebrovascular disease. We assess the influence on sleep of the physical environment, including the ambient environment with noise levels and the built environment. We also describe the influences on sleep health and stroke risk of social determinants of health, including the chronic stressor of racial discrimination. Finally, we discuss how changes in historical neighborhood characteristics or societal policies can influence the social factors affecting sleep health and stroke risk among socioeconomically disadvantaged groups or ethnic and racial minorities. Given the regional and racial or ethnic differences in stroke risk across the United States, an understanding of novel vascular risk factors, such as the multifaceted role of sleep health, will be critical to develop effective public policies to improve population health.

Abstract WMP101: Plasma Proteomic Determinants Of White Matter Hyperintensities And Covert Brain Infarction In The Cardiovascular Health Study

Background: Identification of novel biomarkers of cerebral small vessel disease is critical to elucidate pathophysiology and guide therapeutic development for prevention. We evaluated plasma proteomic associations of clinically asymptomatic, covert brain infarction (cBI) and white matter hyperintensity (WMH) burden on cranial magnetic resonance imaging (MRI) in the population-based Cardiovascular Health Study (CHS).

Methods: Eligible CHS participants underwent one or two cranial MRI scans (~5 years apart) and aptamer-based SOMAScan platform measurement of up to 7288 plasma proteins concurrent with the initial MRI. cBI was defined by MRI signal characteristics and size ≥ 3 mm, and WMH burden was graded (WMG) 0 (least) to 9 (most severe). The relationship between 1-standard deviation increase in each log 2 -normalized plasma protein fluorescence was modeled separately with incident cBI and WMG worsening (≥1 grade increase) using multivariable relative risk regression, adjusting for demographics, estimated glomerular filtration rate (eGFR), and stroke risk factors. In secondary analyses, multivariable linear regression evaluated the cross-sectional relationship between each plasma protein with number of cBI and WMG on initial MRI. Bonferroni correction, based on the number of principal components that explained 99% of the protein fluorescence variance in CHS participants, accounted for multiple comparisons (p<2.1x10 -5 (0.05/2377)).

Results: For eligible participants (n=2615), mean age was 74.4 ± 4.9 years, 61.7% were women, and 16.4% were Black. After adjustment for demographics, eGFR, and stroke risk factors, multiple circulating proteins were associated with cBI and WMG (Table).

Conclusion: Multiple plasma proteins - implicated in systemic inflammation, fatty acid metabolism, neuronal adhesion/migration, and cellular cytoskeletal integrity/remodeling - were independently associated with cBI and WMG in a cohort of older adults.

Association of Obesity With Cognitive Decline in Black and White Americans

BACKGROUND AND OBJECTIVES

There are disparities in the prevalence of obesity by race, and the relationship between obesity and cognitive decline is unclear. The objective of this study was to determine whether obesity is independently associated with cognitive decline and whether the association between obesity and cognitive decline differs in Black and White adults. We hypothesized that obesity is associated with greater cognitive decline compared with normal weight and that the effect of obesity on cognitive decline is more pronounced in Black adults compared with their White counterparts.

METHODS

We pooled data from 28,867 participants free of stroke and dementia (mean, SD: age 61 [10.7] years at the first cognitive assessment, 55% female, 24% Black, and 29% obese) from 6 cohorts. The primary outcome was the annual change in global cognition. We performed linear mixed-effects models with and without time-varying cumulative mean systolic blood pressure (SBP) and fasting plasma glucose (FPG). Global cognition was set to a t-score metric (mean 50, SD 10) at a participant's first cognitive assessment; a 1-point difference represents a 0.1 SD difference in global cognition across the 6 cohorts. The median follow-up was 6.5 years (25th percentile, 75th percentile: 5.03, 20.15).

RESULTS

Obese participants had lower baseline global cognition than normal-weight participants (difference in intercepts, -0.36 [95% CI, -0.46 to -0.17]; p < 0.001). This difference in baseline global cognition was attenuated but was borderline significant after accounting for SBP and FPG (adjusted differences in intercepts, -0.19 [95% CI, -0.39 to 0.002]; p = 0.05). There was no difference in the rate of decline in global cognition between obese and normal-weight participants (difference in slope, 0.009 points/year [95% CI, -0.009 to 0.03]; p = 0.32). After accounting for SBP and FPG, obese participants had a slower decline in global cognition (adjusted difference in slope, 0.03 points/year slower [95% CI, 0.01 to 0.05]; p < 0.001). There was no evidence that race modified the association between body mass index and global cognitive decline (p = 0.34).

DISCUSSION

These results suggest that obesity is associated with lower initial cognitive scores and may potentially attenuate declines in cognition after accounting for BP and FPG.

Educational and Clinical Associations With Longitudinal Cognitive Function and Brain Imaging in American Indians: The Strong Heart Study

BACKGROUND AND OBJECTIVES

Little is known about incidence of vascular and Alzheimer dementias in American Indians.

METHODS

We conducted a large, heterogeneous, population-based, longitudinal cohort study of brain aging in community-dwelling American Indians aged 64-95 years from 11 tribes across 3 states, with neurologic examinations, 1.5T MRI, and extensive cognitive testing. Visit 1 in 2010-2013 (n = 817) and visit 2 in 2017-2019 (n = 403) included all willing, surviving participants. Standardized cognitive tests at both visits included Modified Mini-Mental Status Examination (MMSE), Wechsler Adult Intelligence Scale digit symbol coding (WAIS), Controlled Oral Word Association (COWA), and California Verbal Learning Test short form (CVLT). Test materials added at follow-up included Wide Range Achievement (reading) Test (WRAT) and National Alzheimer Coordinating Center Uniform Data Set cognitive battery (v3 form C2), including Montreal Cognitive Assessment (MoCA). MRI neuroradiologists coded infarcts, hemorrhages, white matter hyperintensities, sulcal atrophy, and ventricle enlargement.

RESULTS

The mean time between examinations was 6.7 years (SD 1.1, range 3.8-9.1 years). Years of formal education had modest correlation with WRAT reading score (r = 0.45). Prevalence and incidence (respectively) of infarcts were 32% and 12.8/1,000 person-years (PYs) hemorrhages 6% and 4.4/1000 PY worsening sulci 74% and 19.0/1000 PY worsening ventricle 79% and 30.1/1000 PY worsening leukoaraiosis 44% and 26.1/1000 PY. Linear losses per year in cognitive scores were 0.6% MMSE, 1.2% WAIS, 0.6% COWA, and 2.2% CVLT. The mean MoCA scores were 18.9 (SD 4.3).

DISCUSSION

These are the first data on longitudinal cognitive and imaging changes in American Indians and first reports of Alzheimer disease-related features. The mean scores in MoCA were similar or lower than standard cutoffs used to diagnose dementia in other racial/ethnic groups, suggesting that standardized cognitive tests may not perform well in this population. Test validation, adaptation, and score adjustment are warranted. Years of education were a poor proxy for premorbid function, suggesting novel methods for cognitive score contextualization is also needed in this population. Evaluation of selective survival suggests attrition from death, and frailty should be accounted for in causal analyses. Overall, these data represent a unique opportunity to examine neurology topics of critical importance to an understudied population.

APOE genotype, hippocampus, and cognitive markers of Alzheimer's disease in American Indians: Data from the Strong Heart Study

BACKGROUND

The apolipoprotein E (APOE) ε4 allele confers higher risk of neurodegeneration and Alzheimer's disease (AD), but differs by race/ethnicity. We examined this association in American Indians.

METHODS

The Strong Heart Study is a population-based cohort of American Indians who were 64 to 95 years of age in 2010 to 2013. APOE ε4 status, brain imaging, and neuropsychological testing was collected in N = 811 individuals. Summary statistics, graphics, and generalized linear regressions-adjusted for sociodemographics, clinical features, and intracranial volume with bootstrap variance estimator-compared APOE ε4 carriers with non-carriers.

RESULTS

APOE ε4 carriers comprised 22% of the population (0.7% homozygotes). Participants were mean 73 years, 67% female, and 54% had some college education. The majority were obese (>50%), hypertensive (>80%), and diabetic (>50%). Neither imaging findings nor multidomain cognitive testing showed any substantive differences between APOE ε4 carriers and non-carriers.

CONCLUSION

We found no evidence of neurodegenerative risk from APOE ε4 in American Indians. Additional studies are needed to examine potential protective features.

Stroke genetics informs drug discovery and risk prediction across ancestries

Previous genome-wide association studies (GWASs) of stroke - the second leading cause of death worldwide - were conducted predominantly in populations of European ancestry1,2. Here, in cross-ancestry GWAS meta-analyses of 110,182 patients who have had a stroke (five ancestries, 33% non-European) and 1,503,898 control individuals, we identify association signals for stroke and its subtypes at 89 (61 new) independent loci: 60 in primary inverse-variance-weighted analyses and 29 in secondary meta-regression and multitrait analyses. On the basis of internal cross-ancestry validation and an independent follow-up in 89,084 additional cases of stroke (30% non-European) and 1,013,843 control individuals, 87% of the primary stroke risk loci and 60% of the secondary stroke risk loci were replicated (P < 0.05). Effect sizes were highly correlated across ancestries. Cross-ancestry fine-mapping, in silico mutagenesis analysis3, and transcriptome-wide and proteome-wide association analyses revealed putative causal genes (such as SH3PXD2A and FURIN) and variants (such as at GRK5 and NOS3). Using a three-pronged approach4, we provide genetic evidence for putative drug effects, highlighting F11, KLKB1, PROC, GP1BA, LAMC2 and VCAM1 as possible targets, with drugs already under investigation for stroke for F11 and PROC. A polygenic score integrating cross-ancestry and ancestry-specific stroke GWASs with vascular-risk factor GWASs (integrative polygenic scores) strongly predicted ischaemic stroke in populations of European, East Asian and African ancestry5. Stroke genetic risk scores were predictive of ischaemic stroke independent of clinical risk factors in 52,600 clinical-trial participants with cardiometabolic disease. Our results provide insights to inform biology, reveal potential drug targets and derive genetic risk prediction tools across ancestries.

Left Atrial Function and Arrhythmias in Relation to Small Vessel Disease on Brain MRI: The Multi-Ethnic Study of Atherosclerosis

Background

Atrial fibrillation (AF) is associated with increased stroke risk and accelerated cognitive decline, but the association of early manifestations of left atrial (LA) impairment with subclinical changes in brain structure is unclear. We investigated whether abnormal LA structure and function, greater supraventricular ectopy, and intermittent AF are associated with small vessel disease on magnetic resonance imaging of the brain.

Methods and Results

In the Multi‐Ethnic Study of Atherosclerosis, 967 participants completed 14‐day ambulatory electrocardiographic monitoring, speckle tracking echocardiography and, a median 17 months later, magnetic resonance imaging of the brain. We assessed associations of LA volume index and reservoir strain, supraventricular ectopy, and prevalent AF with brain magnetic resonance imaging measures of small vessel disease and atrophy. The mean age of participants was 72 years; 53% were women. In multivariable models, LA enlargement was associated with lower white matter fractional anisotropy and greater prevalence of microbleeds; reduced LA strain, indicating worse LA function, was associated with more microbleeds. More premature atrial contractions were associated with lower total gray matter volume. Compared with no AF, intermittent AF (prevalent AF with <100% AF during electrocardiographic monitoring) was associated with lower white matter fractional anisotropy (−0.25 SDs [95% CI, −0.44 to −0.07]) and greater prevalence of microbleeds (prevalence ratio: 1.42 [95% CI, 1.12–1.79]).

Conclusions

In individuals without a history of stroke or transient ischemic attack, alterations of LA structure and function, including enlargement, reduced strain, frequent premature atrial contractions, and intermittent AF, were associated with increased markers of small vessel disease. Detailed assessment of LA structure and function and extended ECG monitoring may enable early identification of individuals at greater risk of small vessel disease.

Epilepsy, Vascular Risk Factors, and Cognitive Decline in Older Adults: The Cardiovascular Health Study

Objective:

Recent studies have shown that global cognitive ability tends to decline faster over time in older adults (≥65 years) with epilepsy compared with older adults without epilepsy. Scarce data exist about the role of vascular risk factors (VRFs) on cognitive course in epilepsy. We assessed whether the associations of individual VRFs with cognitive trajectory differed depending on the presence of prevalent epilepsy.

Methods:

The Cardiovascular Health Study is a population-based longitudinal cohort study of 5,888 US adults aged ≥65 years. Cognitive function was assessed annually with Modified Mini-

Mental State Exam (3MS; global cognitive ability) and Digit Symbol Substitution Test (DSST; information processing speed). We used linear mixed models to estimate the individual and joint associations of epilepsy and VRFs with cognitive decline by modeling epilepsy × VRF interactions one by one, each adjusted for all other VRFs considered, including demographics, health behaviors, clinical characteristics, and comorbid diagnoses. From these models, we estimated excess mean cognitive decline due to interaction of epilepsy with each VRF.

Results:

We observed excess mean decline in global cognitive ability (3MS) due to interactions of epilepsy with hypertension (6.6 points greater mean 8-year decline than expected if no interaction; 95% CI: 1.3, 12.0) and with abstaining from alcohol (5.8 points greater than expected; 95% CI: 0.3, 11.3). We also observed excess mean decline in information processing speed (DSST) due to interactions of epilepsy with prior stroke (18.1 points greater mean 9-year decline than expected; 95% CI: 7.6, 28.5), with abstaining from alcohol (6.1 points greater than expected; 95% CI: 2.5, 9.8), and with higher triglyceride levels (2.4 points greater than expected per standard deviation; 95% CI: 0.4, 4.3).

Conclusion:

Associations of some VRFs with cognitive decline in older adults are stronger in the presence of epilepsy, suggesting a need for greater attention to vascular protection for preserving brain health in older adults with epilepsy.

Prognosis Predictions by Families, Physicians, and Nurses of Patients with Severe Acute Brain Injury: Agreement and Accuracy

BACKGROUND

Effective shared decision-making relies on some degree of alignment between families and the medical team regarding a patient's likelihood of recovery. Patients with severe acute brain injury (SABI) are often unable to participate in decisions, and therefore family members make decisions on their behalf. The goal of this study was to evaluate agreement between prognostic predictions by families, physicians, and nurses of patients with SABI regarding their likelihood of regaining independence and to measure each group's prediction accuracy.

METHODS

This observational cohort study, conducted from 01/2018 to 07/2020, was based in the neuroscience and medical/cardiac intensive care units of a single center. Patient eligibility included a diagnosis of SABI-specifically stroke, traumatic brain injury, or hypoxic ischemic encephalopathy-and a Glasgow Coma Scale ≤ 12 after hospital day 2. At enrollment, families, physicians, and nurses were asked separately to predict a patient's likelihood of recovering to independence within 6 months on a 0-100 scale, regardless of whether a formal family meeting had occurred. True outcome was based on modified Rankin Scale assessment through a family report or medical chart review. Prognostic agreement was measured by (1) intraclass correlation coefficient; (2) mean group prediction comparisons using paired Student's t-tests; and (3) prevalence of concordance, defined as an absolute difference of less than 20 percentage points between predictions. Accuracy for each group was measured by calculating the area under a receiver operating characteristic curve (C statistic) and compared by using DeLong's test.

RESULTS

Data were collected from 222 patients and families, 45 physicians, and 103 nurses. Complete data on agreement and accuracy were available for 187 and 177 patients, respectively. The intraclass correlation coefficient, in which 1 indicates perfect correlation and 0 indicates no correlation, was 0.49 for physician-family pairs, 0.40 for family-nurse pairs, and 0.66 for physician-nurse pairs. The difference in mean predictions between families and physicians was 23.5 percentage points (p < 0.001), 25.4 between families and nurses (p < 0.001), and 1.9 between physicians and nurses (p = 0.38). Prevalence of concordance was 39.6% for family-physician pairs, 30.0% for family-nurse pairs, and 56.2% for physician-nurse pairs. The C statistic for prediction accuracy was 0.65 for families, 0.82 for physicians, and 0.76 for nurses. The p values for differences in C statistics were < 0.05 for family-physician and family-nurse groups and 0.18 for physician-nurse groups.

CONCLUSIONS

For patients with SABI, agreement in predictions between families, physicians, and nurses regarding likelihood of recovery is poor. Accuracy appears higher for physicians and nurses compared with families, with no significant difference between physicians and nurses.

Supranormal Left Ventricular Ejection Fraction, Stroke Volume, and Cardiovascular Risk: Findings From Population-Based Cohort Studies

BACKGROUND

Supranormal ejection fraction by echocardiography in clinically referred patient populations has been associated with an increased risk of cardiovascular disease (CVD). The prognostic implication of supranormal left ventricular ejection fraction (LVEF)-assessed by cardiac magnetic resonance (CMR)-in healthy, community-dwelling individuals is unknown.

OBJECTIVES

The purpose of this study is to investigate the prognostic implication of supranormal LVEF as assessed by CMR and its inter-relationship with stroke volume among community-dwelling adults without CVD.

METHODS

Participants from the MESA (Multi-Ethnic Study of Atherosclerosis) and DHS (Dallas Heart Study) cohorts free of CVD who underwent CMR with LVEF above the normal CMR cutoff (≥57%) were included. The association between cohort-specific LVEF categories and risk of clinically adjudicated major adverse cardiovascular events (MACE) was assessed using adjusted Cox models. Subgroup analysis was also performed to evaluate the association of LVEF and risk of MACE among individuals stratified by left ventricular stroke volume index.

RESULTS

The study included 4,703 participants from MESA and 2,287 from DHS with 727 and 151 MACE events, respectively. In adjusted Cox models, the risk of MACE was highest among individuals in LVEF Q4 (vs Q1) in both cohorts after accounting for potential confounders (MESA: HR = 1.27 [95% CI: 1.01-1.60], P = 0.04; DHS: HR = 1.72 [95% CI: 1.05-2.79], P = 0.03). A significant interaction was found between the continuous measures of LVEF and left ventricular stroke volume index (P interaction = 0.02) such that higher LVEF was significantly associated with an increased risk of MACE among individuals with low but not high stroke volume.

CONCLUSIONS

Among community-dwelling adults without CVD, LVEF in the supranormal range is associated with a higher risk of adverse cardiovascular outcomes, particularly in those with lower stroke volume.

Proteomics and Population Biology in the Cardiovascular Health Study (CHS): design of a study with mentored access and active data sharing

BACKGROUND

In the last decade, genomic studies have identified and replicated thousands of genetic associations with measures of health and disease and contributed to the understanding of the etiology of a variety of health conditions. Proteins are key biomarkers in clinical medicine and often drug-therapy targets. Like genomics, proteomics can advance our understanding of biology.

METHODS AND RESULTS

In the setting of the Cardiovascular Health Study (CHS), a cohort study of older adults, an aptamer-based method that has high sensitivity for low-abundance proteins was used to assay 4979 proteins in frozen, stored plasma from 3188 participants (61% women, mean age 74 years). CHS provides active support, including central analysis, for seven phenotype-specific working groups (WGs). Each CHS WG is led by one or two senior investigators and includes 10 to 20 early or mid-career scientists. In this setting of mentored access, the proteomic data and analytic methods are widely shared with the WGs and investigators so that they may evaluate associations between baseline levels of circulating proteins and the incidence of a variety of health outcomes in prospective cohort analyses. We describe the design of CHS, the CHS Proteomics Study, characteristics of participants, quality control measures, and structural characteristics of the data provided to CHS WGs. We additionally highlight plans for validation and replication of novel proteomic associations.

CONCLUSION

The CHS Proteomics Study offers an opportunity for collaborative data sharing to improve our understanding of the etiology of a variety of health conditions in older adults.

Fishing for health: Neighborhood variation in fish intake, fish quality and association with stroke risk among older adults in the Cardiovascular Health Study

BACKGROUND AND AIMS

Fish consumption has been associated with better health outcomes. Dietary patterns may vary substantially by neighborhood of residence. However, it is unclear if the benefits of a healthy diet are equivalent in different communities. This study examines associations of fish consumption with stroke incidence and stroke risk factors, and whether these differ by neighborhood socioeconomic status (NSES).

METHODS AND RESULTS

We studied 4007 participants in the Cardiovascular Health Study who were 65 years or older and recruited between 1989 and 1990 from 4 US communities. Outcomes included fish consumption type (bakes/broiled vs. fried) and frequency, stroke incidence, and stroke risk factors. Multilevel regressions models were used to estimate fish consumption associations with clinical outcomes. Lower NSES was associated with higher consumption of fried fish (aOR = 1.47, 95% CI: 1.10-1.98) and lower consumption of non-fried fish (0.64, 0.47-0.86). Frequent fried fish (11.9 vs. 9.2 person-years for at least once weekly vs. less than once a month, respectively) and less frequent non-fried fish (17.7 vs. 9.6 person-years for less than once a month vs. at least once weekly, respectively) were independently associated with an increased risk of stroke (p-values < 0.05). However, among those with similar levels of healthy fish consumption, residents with low NSES had less benefit on stroke risk reduction, compared with high NSES.

CONCLUSION

Fish consumption type and frequency both impact stroke risk. Benefits of healthy fish consumption differ by neighborhood socioeconomic status.

Longitudinal Changes in Hearing and Visual Impairments and Risk of Dementia in Older Adults in the United States

IMPORTANCE

Hearing and vision problems are individually associated with increased dementia risk, but the impact of having concurrent hearing and vision deficits, ie, dual sensory impairment (DSI), on risk of dementia, including its major subtypes Alzheimer disease (AD) and vascular dementia (VaD), is not well known.

OBJECTIVE

To evaluate whether DSI is associated with incident dementia in older adults.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study from the Cardiovascular Health Study (CHS) was conducted between 1992 and 1999, with as many as 8 years of follow-up. The multicenter, population-based sample was recruited from Medicare eligibility files in 4 US communities with academic medical centers. Of 5888 participants aged 65 years and older in CHS, 3602 underwent cranial magnetic resonance imaging and completed the modified Mini-Mental State Examination in 1992 to 1994 as part of the CHS Cognition Study. A total of 227 participants were excluded due to prevalent dementia, leaving a total of 3375 participants without dementia at study baseline. The study hypothesis was that DSI would be associated with increased risk of dementia compared with no sensory impairment. The association between the duration of DSI with risk of dementia was also evaluated. Data analysis was conducted from November 2019 to February 2020.

EXPOSURES

Hearing and vision impairments were collected via self-report at baseline and as many as 5 follow-up visits.

MAIN OUTCOMES AND MEASURES

All-cause dementia, AD, and VaD, classified by a multidisciplinary committee using standardized criteria.

RESULTS

A total of 2927 participants with information on hearing and vision at all available study visits were included in the analysis (mean [SD] age, 74.6 [4.8] years; 1704 [58.2%] women; 455 [15.5%] African American or Black; 2472 [85.5%] White). Compared with no sensory impairment, DSI was associated with increased risk of all-cause dementia (hazard ratio [HR], 2.60; 95% CI, 1.66-2.06; P < .001), AD (HR, 3.67; 95% CI, 2.04-6.60; P < .001) but not VaD (HR, 2.03; 95% CI, 1.00-4.09; P = .05).

CONCLUSIONS AND RELEVANCE

In this cohort study, DSI was associated with increased risk of dementia, particularly AD. Evaluation of hearing and vision in older adults may help to identify those at high risk of developing dementia.

Association of Brain Volumes and White Matter Injury With Race, Ethnicity, and Cardiovascular Risk Factors: The Multi-Ethnic Study of Atherosclerosis

Background Cardiovascular risk factors are associated with cognitive decline and dementia. Magnetic resonance imaging provides sensitive measurement of brain morphology and vascular brain injury. However, associations of risk factors with brain magnetic resonance imaging findings have largely been studied in White participants. We investigated associations of race, ethnicity, and cardiovascular risk factors with brain morphology and white matter (WM) injury in a diverse population. Methods and Results In the Multi-Ethnic Study of Atherosclerosis, measures were made in 2018 to 2019 of total brain volume, gray matter and WM volume, and WM injury, including WM hyperintensity volume and WM fractional anisotropy. We assessed cross-sectional associations of race and ethnicity and of cardiovascular risk factors with magnetic resonance imaging measures. Magnetic resonance imaging data were complete in 1036 participants; 25% Black, 15% Chinese-American, 19% Hispanic, and 41% White. Mean (SD) age was 72 (8) years and 53% were women. Although WM injury was greater in Black than in White participants in a minimally adjusted model, additional adjustment for cardiovascular risk factors and socioeconomic status each attenuated this association, rendering it nonsignificant. Overall, greater average WM hyperintensity volume was associated with older age and current smoking (69% greater vs never smoking); lower fractional anisotropy was additionally associated with higher diastolic blood pressure, use of antihypertensive medication, and diabetes. Conclusions We found no statistically significant difference in measures of WM injury by race and ethnicity after adjustment for cardiovascular risk factors and socioeconomic status. In all racial and ethnic groups, older age, current smoking, hypertension, and diabetes were strongly associated with WM injury.

Association of Serum Neurofilament Light Chain Concentration and MRI Findings in Older Adults: The Cardiovascular Health Study

BACKGROUND AND OBJECTIVES

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

METHODS

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

RESULTS

In fully adjusted models, log2(NfL) concentration was associated with WMG (β = 0.27; p = 2.3 × 10-4) and worsening WMG (relative risk [RR] 1.24; p = 0.0022), but less strongly with prevalent brain infarcts (RR 1.18; p = 0.013) and not with incident brain infarcts (RR 1.18; p = 0.18). Associations were also present with WMH volume (β = 2,242.9, p = 0.0036). For the other 3 biomarkers, the associations for log2 (GFAP) concentration with WMG and worsening WMG were significant.

DISCUSSION

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

Abstract WP113: Cerebrospinal Creatine Kinase BB Isoenzyme: A Biomarker For Predicting Never Awakening In Patients Treated With Therapeutic Hypothermia After Cardiac Arrest

Introduction: Creatine kinase BB isoenzyme (CK-BB) levels in CSF after cardiac arrest (CA) have been shown to predict never awakening though have not been evaluated in patients treated with therapeutic hypothermia (TH). Clinically, CSF CK-BB is tested in those who have not already awakened and are suspected of having a poor prognosis. We aimed to evaluate CSF CK-BB as a prognostic biomarker in the era of TH.

Methods: We performed a retrospective cohort study at a single institution of CA patients admitted between 2010 and 2020 and with CSF CK-BB assayed between 36 and 84 hours after CA. We examined the proportion of patients who awakened at hospital discharge and latest follow up in the electronic health record for various CSF CK-BB thresholds. We examined concordance and additive value somatosensory evoked potentials (SSEP). Awakening was defined as following commands or having comprehensible speech.

Results: Among 214 eligible patients, mean age was 55 ± 15 years, 72% were male, 33% were non-white, 17% had initial ventricular fibrillation or tachycardia, 90% were out-of-hospital CA, and 83% had TH. A total of 19 (9%) awoke at a mean of 22 ± 28 days. Two patients in a vegetative state at discharge later awoke at 73 (CSF CK-BB 163 U/L) and 101 days (228 U/L). A CSF CK-BB cut-off of ≥ 230 U/L predicted never awakening with a specificity of 100% (binomial 95% CI 82-100%) and a sensitivity of 69% (95% CI 62-76%). When combined with bilaterally absent SSEP, the specificity remained 100% while the sensitivity increased to 80% (95% CI 73-85%). Results were similar after excluding 165 (77%) who had withdrawal of life-sustaining treatment. Discordant findings among 149 patients who had both studies were seen in 13 (9%) with intact SSEP bilaterally but CSF CK-BB ≥ 230 U/L and in 20 (13%) with absent SSEP bilaterally but CSF CK-BB < 230, none of whom awoke.

Conclusion: CSF CK-BB levels accurately predict never awakening among CA survivors treated with TH. As part of multimodal prognostic testing with SSEP, the CSF CK-BB cutoff of 230 can optimize sensitivity while maintaining a specificity of 100%. These results are susceptible to a self-fulfilling prophecy, and specificity has a large confidence interval because only a small number of eligible patients awakened.

Abstract TP190: Association Of Age, Sex, Race, Weight, And Height With Biomarkers Of Atrial Cardiopathy In Patients With Embolic Stroke Of Undetermined Source

Introduction: Elevated N-terminal pro-brain natriuretic peptide (NT-proBNP) and prolonged P-wave terminal force in V1 (PTFV1) on 12-lead ECG are associated with increased risk of atrial fibrillation and stroke. Age is positively associated with NT-proBNP, men have lower levels than women, and Blacks have lower levels than Whites. Although both weight and height are positively related to risk of atrial fibrillation, both are negatively associated with NT-proBNP. We explored associations among these variables in patients with embolic stroke of undetermined source (ESUS).

Methods: In an ongoing randomized trial of secondary stroke prevention, AtRial Cardiopathy and Antithrombotic Drugs In Prevention After Cryptogenic Stroke (ARCADIA), as of 2021 August, 2616 ESUS patients were consented for the trial and screened for atrial cardiopathy with serum NT-proBNP and PTFV1. Baseline information on age, sex, race, weight, and height were used in sequential linear regression analyses to understand associations with ln(NT-proBNP) and ln(PTFV1).

Results: In age-adjusted models of ln(NT-proBNP), significant negative associations were found for weight (beta -0.004, p=0.02) and height (beta -0.013, p<001). When sex was added to these models, significance was lost for weight and height. In a final model including all of these variables (N=2400), significant associations were found for age (beta 0.044, p<0.001), sex (men with lower levels than women, beta -0.448, p<0.001) and race (Blacks with lower levels than Whites, beta -0.141, p=0.027 and Asians with lower levels than Whites, beta -0.512, p=0.009). In similar sequential models for ln(PTFV1), only race was significant; in a final model, Blacks had higher values than Whites, beta 0.275, p<0.001. No evidence was found in these models to suggest violation of linearity.

Conclusions: In a population of patients with ESUS, associations of weight and height with NT-proBNP are confounded not by age but by sex. Key associations with NT-proBNP include age, sex, and race. In ARCADIA, understanding these associations may be important in individualizing predictions about which ESUS patients with atrial cardiopathy are most likely to benefit from apixaban over aspirin for secondary stroke prevention.

Abstract TP211: Identifying Factors Associated With Higher Risk Of Stroke In Patients With Infective Endocarditis Using The National Inpatient Sample

Background: Cerebrovascular complications (ischemic stroke (IS), intracerebral hemorrhage (ICH) or subarachnoid hemorrhage (SAH)) of infective endocarditis (IE) are common and substantially increase morbidity and mortality. We aimed to identify risk factors for stroke in a nationally representative population of hospitalized IE patients from the US.

Methods: Patient hospitalizations for IE and stroke were identified using validated International Classification of Diseases 10 diagnosis codes from the Q4 2015-2018 National Inpatient Sample. We evaluated the association between demographics, known risk factors (opioid use, cardiac valve replacement, and mitral valve disease), and Elixhauser comorbidity index-defined factors with the diagnosis of stroke using logistic regression.

Results: Of the 53,557 patients with a diagnosis of IE, 5,754 (10.7%) had a concurrent diagnosis of stroke (75% IS, 6.9% ICH, 4.5% SAH, 14% multiple stroke types). The mean age at IE diagnosis was 59 years; 42.3% were female; 71.8% Caucasian, 14.2% Black, 7.8% Hispanic, 2.7% Asian, and 0.8% Native American; 9.2% of patients died during hospitalization (7.5% without stroke, 23% with stroke, p<0.001). Factors independently associated with stroke are shown in the Table; the C-statistic was 0.63. Opioid use and cardiac valve replacement were not associated with stroke.

Conclusion: In this large, nationally representative sample of hospitalized IE patients, comorbidities independently associated with higher odds of stroke included mitral valve disease, metastatic cancer, coagulopathy, weight loss, and electrolyte disorders. Detailed clinical data, not available from this administrative data set, may allow better prediction of stroke, but our findings may suggest areas for additional research.

Abstract 141: Atrial Cardiopathy And Left Ventricular Dysfunction In Patients With ESUS: Findings From The Arcadia Trial

Background: Recent data suggest biomarkers of atrial cardiopathy (ACP) can potentially identify a subset of patients with cryptogenic stroke who may benefit from anticoagulation. However, the specificity of these markers for atrial disease and their independence from measures of more global cardiac dysfunction remain unclear. We hypothesized that biomarkers of ACP collectively reflect left atrial pathology and are not strongly affected by coexisting left ventricular dysfunction.

Methods: ARCADIA is an ongoing multicenter trial comparing standard dose apixaban to aspirin therapy in patients with Embolic Stroke of Undetermined Source (ESUS) with ACP, defined as either N-terminal pro-brain natriuretic peptide [NT-proBNP] > 250 pg/mL; P wave terminal force velocity on ECG lead V1 [PTFV1] > 5000 μV*ms; or echocardiographic left atrial diameter index [LADI] ≥ 3 cm/m 2 . Pearson correlation coefficients and descriptive statistics were used to examine the relationship between left ventricular ejection fraction (LVEF) and ACP biomarkers.

Results: Among 2,616 ESUS patients screened, 1,046 met ≥ 1 ACP criterion (665 BNP, 531 PTFV1, 14 LADI). Patients with ACP were older (68 ± 11 vs 64 ± 10 years) and 54.5% were women. The great majority (84%) of subjects with ACP had normal LVEF (≥55%). Among them there was no correlation between LVEF and NT-proBNP (r= -0.01, P= 0.5) or PTFV1 (r=0.002, P=0.9). In patients with abnormal LVEF, there was a strong inverse correlation of LVEF with NT-proBNP (r=-0.4, P<0.001), but no correlation with PTFV1 (r=0.11, P=0.16). The LADI criterion was only met in a few patients, precluding further analyses. Among patients with NT-proBNP >250 pg/mL and measured LVEF (n=435), only 19% had abnormal LVEF. Compared to patients with abnormal NT-proBNP alone, those with both abnormal NT-proBNP and abnormal LVEF were younger (66.4 ± 11.0 vs. 71.6 ± 11.0, P<0.001), more often African American (29.6% vs. 11.5%, P<0.001), and more often male (56% vs. 40%, P=0.01).

Conclusion: Left ventricular dysfunction (EF ≤ 55%) is uncommon in patients with ACP as defined in ARCADIA. These findings suggest that, among patients with ESUS, atrial cardiopathy may represent a separate entity from LV dysfunction.

Abstract 122: Untargeted Proteomics And Carotid Artery Atherosclerosis: The Cardiovascular Health Study

Background: Increased carotid intima-media thickness (cIMT) and moderate-severe carotid artery atherosclerosis (CAA≥50%) are associated with increased risk of stroke. We evaluated proteomic determinants of increased cIMT and CAA≥50% in the population-based Cardiovascular Health Study (CHS).

Methods: Eligible participants underwent carotid artery ultrasound and aptamer-based SOMAScan platform measurement of 1298 serum proteins from the concurrent study visit. cIMT was defined as the average of the standardized values of the maximal common carotid artery IMT and maximal internal carotid artery IMT. CAA≥50% was defined as carotid plaque resulting in ≥50% luminal stenosis. The relationship between each log-normalized protein concentration with cIMT and CAA≥50% was modeled separately using multivariable linear regression and logistic regression, respectively, adjusting for demographics, estimated glomerular filtration rate (eGFR), and CAA risk factors. Bonferroni correction, based on the number of principal components that explained 95% of the protein concentration variance in CHS participants, was employed to account for multiple hypothesis testing, yielding a p -value for significance of <7.6x10 -5 (0.05/661).

Results: For eligible participants (n=2783), mean age was 74.4 ± 4.9 years, 39.5% were men, and 15.8% were Black. After adjustment for demographics, eGFR, and CAA risk factors, 13 proteins were independently associated with increased cIMT (Table). The magnitude and direction of the associations were similar in subgroups defined by sex and race. Three proteins were associated with CAA≥50%, after adjusting for eGFR and demographics (Table); however, associations were no longer significant after adjusting for CAA risk factors.

Conclusion: Multiple novel serum proteins - implicated in extracellular matrix remodeling, systemic inflammation, and coagulation - were independently associated with increased cIMT in a cohort of older adults.

Abstract TP189: Atrial Fibrillation, Age, And Ischemic Stroke Severity In A Nationally Representative Dataset

Introduction: Atrial fibrillation (AF), a well-defined ischemic stroke (IS) risk factor whose prevalence increases with age, is associated with higher stroke severity. We aimed to evaluate stroke severity and hospital mortality in a nationally representative sample of AF-related IS patients.

Methods: We utilized data from the National (Nationwide) Inpatient Sample databases from 2015 - 2018 using ICD-10 diagnostic codes to identify individuals with IS and comorbid AF. The NIHSS was used to characterize stroke severity in a subset of cases after 10/1/2016. Nonparametric statistics and logistic regression analyses were conducted to evaluate associations between AF and hospital death.

Results: Of the 382,758 IS cases, 99,566 (26%) had comorbid AF. AF increased linearly with age, reaching at 47% of all hospitalized IS patients 85+ years of age or older (Figure). Higher age, male sex, white race, obesity, and higher median income were associated with comorbid AF, whereas diabetes, hypertension, tobacco use, and hyperlipidemia were associated with reduced odds of comorbid AF. While 5.8% of all IS patients died during hospitalization, mortality was increased nearly two-fold in those with AF (9.0% vs. 4.6%, p<.001). Among in-hospital deaths from IS, comorbid AF increased with age, present in 59% of those 85+ years of age or older (Figure). NIHSS, reported in 21% of patients, was higher in AF patients (mean NIHSS 6 vs. 9, p<.001). High NIHSS was the strongest independent predictor of hospital death.

Conclusion: The burden of AF in a nationally representative sample of hospitalized IS patients is substantial, present in nearly 50% of the 85+ age group. AF-related IS is more severe and more likely to be fatal. As our population ages, the prevalence of AF will only increase. Understanding the severity and fatality of AF-related IS will have profound implications for health systems and may better facilitate anticipatory guidance and AF treatment.

Serum Nonesterified Fatty Acids and Incident Stroke: The CHS

Background

Significant associations between total nonesterified fatty acid (NEFA) concentrations and incident stroke have been reported in some prospective cohort studies. We evaluated the associations between incident stroke and serum concentrations of nonesterified saturated, monounsaturated, polyunsaturated, and trans fatty acids.

Methods and Results

CHS (Cardiovascular Health Study) participants (N=2028) who were free of stroke at baseline (1996–1997) and had an archived fasting serum sample were included in this study. A total of 35 NEFAs were quantified using gas chromatography. Cox proportional hazards regression models were used to evaluate associations of 5 subclasses (nonesterified saturated, monounsaturated, omega (n)‐6 polyunsaturated, n‐3 polyunsaturated, and trans fatty acids) of NEFAs and individual NEFAs with incident stroke. Sensitivity analysis was conducted by excluding cases with hemorrhagic stroke (n=45). A total of 338 cases of incident stroke occurred during the median 10.5‐year follow‐up period. Total n‐3 (hazard ratio [HR], 0.77 [95% CI, 0.61–0.97]) and n‐6 (HR, 1.32 [95% CI, 1.01–1.73]) subclasses of NEFA were negatively and positively associated with incident stroke, respectively. Among individual NEFAs, dihomo‐γ‐linolenic acid (20:3n‐6) was associated with higher risk (HR, 1.29 [95% CI, 1.02–1.63]), whereas cis‐7‐hexadecenoic acid (16:1n‐9c) and arachidonic acid (20:4n‐6) were associated with a lower risk (HR, 0.67 [95% CI, 0.47–0.97]; HR, 0.81 [95% CI. 0.65–1.00], respectively) of incident stroke per standard deviation increment. After the exclusion of cases with hemorrhagic stroke, these associations did not remain significant.

Conclusions

A total of 2 NEFA subclasses and 3 individual NEFAs were associated with incident stroke. Of these, the NEFA n‐3 subclass and dihomo‐γ‐linolenic acid are diet derived and may be potential biomarkers for total stroke risk.

HDL (High-Density Lipoprotein) Subspecies, Prevalent Covert Brain Infarcts, and Incident Overt Ischemic Stroke: Cardiovascular Health Study

BACKGROUND AND PURPOSE

Whether HDL (high-density lipoprotein) is associated with risk of vascular brain injury is unclear. HDL is comprised of many apo (apolipoprotein) species, creating distinct subtypes of HDL.

METHODS

We utilized sandwich ELISA to determine HDL subspecies from plasma collected in 1998/1999 from 2001 CHS (Cardiovascular Health Study) participants (mean age, 80 years).

RESULTS

In cross-sectional analyses, participants with higher apoA1 in plasma and lower apoE in HDL were less likely to have prevalent covert magnetic resonance imaging-defined infarcts: odds ratio for apoA1 Q4 versus Q1, 0.68 (95% CI, 0.50-0.93), and odds ratio for apoE Q4 versus Q1, 1.36 (95% CI, 1.01-1.84). Similarly, apoA1 in the subspecies of HDL that lacked apoC3, apoJ, or apoE was inversely related to covert infarcts, and apoE in the subspecies of HDL that lacked apoC3 or apoJ was directly related to covert infarcts in prospective analyses. In contrast, the concentrations of apoA1 and apoE in the complementary subspecies of HDL that contained these apos were unrelated to covert infarcts. Patterns of associations between incident overt ischemic stroke and apoA1, apoE, and apoA1 and apoE in subspecies of HDL were similar to those observed for covert infarcts but less pronounced.

CONCLUSIONS

This study highlights HDL subspecies defined by apo content as relevant biomarkers of covert and overt vascular brain injury.

Associations between neighborhood greenspace and brain imaging measures in non-demented older adults: the Cardiovascular Health Study

PURPOSE

Greater neighborhood greenspace has been associated with brain health, including better cognition and lower odds of Alzheimer's disease in older adults. We investigated associations between neighborhood greenspace and brain-based magnetic resonance imaging (MRI) measures and potential effect modification by sex or apolipoprotein E genotype (APOE), a risk factor for Alzheimer's disease.

METHODS

We obtained a sample of non-demented participants 65 years or older (n = 1125) from the longitudinal, population-based Cardiovascular Health Study (CHS). Greenspace data were derived from the National Land Cover Dataset. Adjusted multivariable linear regression estimated associations between neighborhood greenspace five years prior to the MRI and left and right hippocampal volume and 10-point grades of ventricular size and burden of white matter hyperintensity. Interaction terms tested effect modification by APOE genotype and sex. CHS data (1989-1999) were obtained/analyzed in 2020.

RESULTS

Participants were on average 79 years old [standard deviation (SD) = 4], 58% were female, and 11% were non-white race. Mean neighborhood greenspace was 38% (SD = 28%). Greater proportion of greenspace in the neighborhood five years before MRI was borderline associated with lower ventricle grade (estimate: - 0.30; 95% confidence interval: - 0.61, 0.00). We observed no associations between greenspace and the other MRI outcome measures and no evidence of effect modification by APOE genotype and sex.

CONCLUSION

This study suggests a possible association between greater greenspace and less ventricular enlargement, a measure reflecting global brain atrophy. If confirmed in other longitudinal cohort studies, interventions and policies to improve community greenspaces may help to maintain brain health in older age.

Cardiac mechanics and incident ischemic stroke: the Cardiovascular Health Study

Recent evidence indicates that our understanding of the relationship between cardiac function and ischemic stroke remains incomplete. The Cardiovascular Health Study enrolled community-dwelling adults ≥ 65 years old. We included participants with speckle-tracking data from digitized baseline study echocardiograms. Exposures were left atrial reservoir strain (primary), left ventricular longitudinal strain, left ventricular early diastolic strain rate, septal e’ velocity, and lateral e’ velocity. The primary outcome was incident ischemic stroke. Cox proportional hazards models were adjusted for demographics, image quality, and risk factors including left ventricular ejection fraction and incident atrial fibrillation. Among 4,000 participants in our analysis, lower (worse) left atrial reservoir strain was associated with incident ischemic stroke (HR per SD absolute decrease, 1.14; 95% CI 1.04–25). All secondary exposure variables were significantly associated with the outcome. Left atrial reservoir strain was associated with cardioembolic stroke (HR per SD absolute decrease, 1.42; 95% CI 1.21–1.67) and cardioembolic stroke related to incident atrial fibrillation (HR per SD absolute decrease, 1.60; 1.32–1.95). Myocardial dysfunction that can ultimately lead to stroke may be identifiable at an early stage. This highlights opportunities to identify cerebrovascular risk earlier and improve stroke prevention via therapies for early myocardial dysfunction.

Comparing Vascular Brain Injury and Stroke by Cranial Magnetic Resonance Imaging, Physician-Adjudication, and Self-Report: Data from the Strong Heart Study

BACKGROUND

Epidemiologic studies often use self-report as proxy for clinical history. However, whether self-report correctly identifies prevalence in minority populations with health disparities and poor health-care access is unknown. Furthermore, overlap of clinical vascular events with covert vascular brain injury (VBI), detected by imaging, is largely unexamined.

METHODS

The Strong Heart Study recruited American Indians from 3 regions, with surveillance and adjudication of stroke events from 1989 to 2013. In 2010-2013, all 817 survivors, aged 65-95 years, underwent brain imaging, neurological history interview, and cognitive testing. VBI was defined as imaged infarct or hemorrhage.

RESULTS

Adjudicated stroke was prevalent in 4% of participants and separately collected, self-reported stroke in 8%. Imaging-defined VBI was detected in 51% and not associated with any stroke event in 47%. Compared with adjudication, self-report had 76% sensitivity and 95% specificity. Participants with adjudicated or self-reported stroke had the poorest performance on cognitive testing; those with imaging-only (covert) VBI had intermediate performance.

CONCLUSION

In this community-based cohort, self-report for prior stroke had good performance metrics. A majority of participants with VBI did not have overt, clinically recognized events but did have neurological or cognitive symptoms. Data collection methodology for studies in a resource-limited setting must balance practical limitations in costs, accuracy, feasibility, and research goals.

Atrial fibrosis in embolic stroke of undetermined source: A multicenter study

BACKGROUND AND PURPOSE

Left atrial (LA) cardiac disease is a suspected cause of embolic stroke of undetermined source (ESUS). We tested the hypothesis that LA fibrosis, quantified using late-gadolinium-enhancement magnetic resonance imaging (LGE-MRI), predicts recurrent stroke or atrial fibrillation (AF) in patients with ESUS.

METHODS

We compared atrial fibrosis in healthy controls and patients with lacunar stroke, ESUS, and known AF with or without prior stroke. We followed patients with ESUS prospectively for the primary outcome of recurrent ischemic stroke, incident AF, or both.

RESULTS

We enrolled 203 patients from three centers: 103 patients without AF (35 healthy controls, 15 with lacunar strokes, 53 with ESUS) and 100 patients with AF (50 with and 50 without prior stroke). Patients with ESUS had significantly higher atrial fibrosis (15.0 ± 6.2%) compared to healthy controls (8.1 ± 7.9%; <0.0001) and compared to lacunar stroke patients (10.8 ± 8.4; p = 0.02), but had comparable fibrosis to patients with AF with (17.9 ± 11.4%) or without prior stroke (16.6 ± 9.2%; p = NS for both). Over a mean follow-up of 19 months, nine of 53 patients (16.9%) with ESUS experienced the combined primary outcome, which included six patients (11.3%) with recurrent ischemic stroke and five patients with incident AF (9.4%). Patients with ESUS with fibrosis ≥12% had a higher proportion of the combined outcome: 25.0% vs. 4.8%; p = 0.039.

CONCLUSIONS

Patients with ESUS demonstrate atrial fibrosis comparable to that seen in AF. Atrial fibrosis ≥12% was associated with recurrent stroke, incident AF or both. This subgroup of ESUS patients may benefit from anticoagulation for secondary prevention of ischemic stroke.

Association Between Intracerebral Hemorrhage and Subsequent Arterial Ischemic Events in Participants From 4 Population-Based Cohort Studies

Importance

Intracerebral hemorrhage and arterial ischemic disease share risk factors, to our knowledge, but the association between the 2 conditions remains unknown.

Objective

To evaluate whether intracerebral hemorrhage was associated with an increased risk of incident ischemic stroke and myocardial infarction.

Design, Setting, and Participants

An analysis was conducted of pooled longitudinal participant-level data from 4 population-based cohort studies in the United States: the Atherosclerosis Risk in Communities (ARIC) study, the Cardiovascular Health Study (CHS), the Northern Manhattan Study (NOMAS), and the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study. Patients were enrolled from 1987 to 2007, and the last available follow-up was December 31, 2018. Data were analyzed from September 1, 2019, to March 31, 2020.

Exposure

Intracerebral hemorrhage, as assessed by an adjudication committee based on predefined clinical and radiologic criteria.

Main Outcomes and Measures

The primary outcome was an arterial ischemic event, defined as a composite of ischemic stroke or myocardial infarction, centrally adjudicated within each study. Secondary outcomes were ischemic stroke and myocardial infarction. Participants with prevalent intracerebral hemorrhage, ischemic stroke, or myocardial infarction at their baseline study visit were excluded. Cox proportional hazards regression was used to examine the association between intracerebral hemorrhage and subsequent arterial ischemic events after adjustment for baseline age, sex, race/ethnicity, vascular comorbidities, and antithrombotic medications.

Results

Of 55 131 participants, 47 866 (27 639 women [57.7%]; mean [SD] age, 62.2 [10.2] years) were eligible for analysis. During a median follow-up of 12.7 years (interquartile range, 7.7-19.5 years), there were 318 intracerebral hemorrhages and 7648 arterial ischemic events. The incidence of an arterial ischemic event was 3.6 events per 100 person-years (95% CI, 2.7-5.0 events per 100 person-years) after intracerebral hemorrhage vs 1.1 events per 100 person-years (95% CI, 1.1-1.2 events per 100 person-years) among those without intracerebral hemorrhage. In adjusted models, intracerebral hemorrhage was associated with arterial ischemic events (hazard ratio [HR], 2.3; 95% CI, 1.7-3.1), ischemic stroke (HR, 3.1; 95% CI, 2.1-4.5), and myocardial infarction (HR, 1.9; 95% CI, 1.2-2.9). In sensitivity analyses, intracerebral hemorrhage was associated with arterial ischemic events when updating covariates in a time-varying manner (HR, 2.2; 95% CI, 1.6-3.0); when using incidence density matching (odds ratio, 2.3; 95% CI, 1.3-4.2); when including participants with prevalent intracerebral hemorrhage, ischemic stroke, or myocardial infarction (HR, 2.2; 95% CI, 1.6-2.9); and when using death as a competing risk (subdistribution HR, 1.6; 95% CI, 1.1-2.1).

Conclusions and Relevance

This study found that intracerebral hemorrhage was associated with an increased risk of ischemic stroke and myocardial infarction. These findings suggest that intracerebral hemorrhage may be a novel risk marker for arterial ischemic events.

BinomiRare: A robust test for association of a rare genetic variant with a binary outcome for mixed models and any case-control proportion

Whole-genome sequencing (WGS) and whole-exome sequencing studies have become increasingly available and are being used to identify rare genetic variants associated with health and disease outcomes. Investigators routinely use mixed models to account for genetic relatedness or other clustering variables (e.g., family or household) when testing genetic associations. However, no existing tests of the association of a rare variant with a binary outcome in the presence of correlated data control the type 1 error where there are (1) few individuals harboring the rare allele, (2) a small proportion of cases relative to controls, and (3) covariates to adjust for. Here, we address all three issues in developing a framework for testing rare variant association with a binary trait in individuals harboring at least one risk allele. In this framework, we estimate outcome probabilities under the null hypothesis and then use them, within the individuals with at least one risk allele, to test variant associations. We extend the BinomiRare test, which was previously proposed for independent observations, and develop the Conway-Maxwell-Poisson (CMP) test and study their properties in simulations. We show that the BinomiRare test always controls the type 1 error, while the CMP test sometimes does not. We then use the BinomiRare test to test the association of rare genetic variants in target genes with small-vessel disease (SVD) stroke, short sleep, and venous thromboembolism (VTE), in whole-genome sequence data from the Trans-Omics for Precision Medicine (TOPMed) program.

Silent Myocardial Infarction and Subsequent Ischemic Stroke in the Cardiovascular Health Study

OBJECTIVE

To test the hypothesis that silent myocardial infarction (MI) is a risk factor for ischemic stroke, we evaluated the association between silent MI and subsequent ischemic stroke in the Cardiovascular Health Study.

METHODS

The Cardiovascular Health Study prospectively enrolled community-dwelling individuals ≥65 years of age. We included participants without prevalent stroke or baseline evidence of MI. Our exposures were silent and clinically apparent, overt MI. Silent MI was defined as new evidence of Q-wave MI, without clinical symptoms of MI, on ECGs performed during annual study visits from 1989 to 1999. The primary outcome was incident ischemic stroke. Secondary outcomes were ischemic stroke subtypes: nonlacunar, lacunar, and other/unknown. Cox proportional hazards analysis was used to model the association between time-varying MI status (silent, overt, or no MI) and stroke after adjustment for baseline demographics and vascular risk factors.

RESULTS

Among 4,224 participants, 362 (8.6%) had an incident silent MI, 421 (10.0%) an incident overt MI, and 377 (8.9%) an incident ischemic stroke during a median follow-up of 9.8 years. After adjustment for demographics and comorbidities, silent MI was independently associated with subsequent ischemic stroke (hazard ratio [HR], 1.51; 95% confidence interval [CI], 1.03-2.21). Overt MI was associated with ischemic stroke both in the short term (HR, 80; 95% CI, 53-119) and long term (HR, 1.60; 95% CI, 1.04-2.44). In secondary analyses, the association between silent MI and stroke was limited to nonlacunar ischemic stroke (HR, 2.40; 95% CI, 1.36-4.22).

CONCLUSION

In a community-based sample, we found an association between silent MI and ischemic stroke.