Educational Attainment and Dementia: Mediation by Mid-Life Vascular Risk Factors.

INTRODUCTION: Lower education is associated with higher burden of vascular risk factors in mid-life and higher risk of dementia in late life. We aim to understand the causal mechanism through which vascular risk factors potentially mediate the relationship between education and dementia. METHODS: In a cohort of 13,368 Black and White older adults in the Atherosclerosis Risk in Communities Study, we assessed the relationship between education (grade school, high school without graduation, high school graduate or equivalent, college, graduate/professional school) and dementia among all participants and among those with incident stroke. Cox models were adjusted for age, race-center (a variable stratified by race and field center), sex, apolipoprotein E (APOE) ε4 genotype, and family history of cardiovascular disease. Causal mediation models assessed mediation by mid-life systolic blood pressure, fasting blood glucose, body mass index, and smoking. RESULTS: More education was associated with 8 to 44% lower risk of dementia compared to grade school-level education in a dose-response pattern, while the relationship between education and post-stroke dementia was not statistically significant. Up to 25% of the association between education and dementia was mediated through mid-life vascular risk factors, with a smaller percentage mediated for lower levels of education. INTERPRETATION: A substantial proportion of the relationship between education and dementia was mediated through mid-life vascular risk factors. However, risk factor modification is unlikely to fully address the large educational disparities in dementia risk. Prevention efforts must also address disparities in socioeconomic resources leading to divergent early-life education and other structural determinants of mid-life vascular risk factors. ANN NEUROL 2023;94:13-26.

Positive aspects of caregiving in incident and long-term caregivers: Role of social engagement and distress.

OBJECTIVES: Positive caregiver adaptation over time may be associated with reports of positive aspects of caregiving (PAC). We examined differences in PAC by caregiving duration and social engagement, controlling for measures of distress. METHODS: Participants included 283 African American or White caregivers from the Caregiving Transitions Study with a wide range of caregiving durations. PAC are defined as positive appraisals that caregivers report about their role, such as feeling appreciated or confident. We fit multivariable linear models with the total PAC score as the outcome to assess its association with years of caregiving and social engagement (social network, monthly social contact). Models were adjusted for age, sex, race, marital status, relationship to care recipient, care recipient's dementia status, perceived stress and caregiving strain. RESULTS: Caregivers with higher social engagement reported significantly higher PAC. A non-significant trend was found in most analytic models for caregivers with longer duration of care to report higher PAC. African American caregivers reported higher PAC compared to White caregivers. Dementia caregivers reported lower PAC than non-dementia caregivers in models adjusting for demographics and social network size, but the association was attenuated with the addition of caregiving strain. DISCUSSION: Higher social engagement and longer duration of care tend to be associated with higher PAC after adjusting for demographics and measures of distress. Future studies should aim to leverage longitudinal data to understand whether caregivers shift appraisal to positive aspects of their role and explore implementation of caregiving interventions targeting PAC in order to improve the caregiving experience.

Sex differences in vascular risk factors, in-hospital management, and outcomes of patients with acute ischemic stroke in China.

BACKGROUND: Previous assessments of sex differences for patients with acute ischemic stroke were limited in a specific region or population, narrow scope, or small sample size. METHODS: Patients with acute ischemic stroke hospitalized in the China Stroke Center Alliance hospitals were analyzed. Absolute standardized differences (ASDs) were used to assess sex differences in vascular risk factors, guideline-recommended in-hospital management measures and outcomes, including stroke severity (National Institutes of Health Stroke Scale≥16), death/discharge against medical advice, major adverse cardiovascular events, pneumonia, and disability (modified Rankin Scale≥3). RESULTS: Of 838,229 patients analyzed, 524351 (62.6%) were men and 313,878 (37.4%) were women. Compared with men, women were older (68.6 vs. 64.7 years), had higher prevalence of hypertension (67.7% vs. 62.4%), diabetes (24.7% vs. 19.5%), and atrial fibrillation (7.1% vs. 4.3%), but lower prevalence of smoking (4.5% vs. 56.6%) and drinking (2.6% vs 35.8%) (ASDs >10%). No sex differences were seen in guideline-directed management measures, indicated by risk-adjusted individual measures and the all-or-null summary measure (34.5% vs 34.9%, ASD = 1.0%). Compared to men, women tended to have strokes that were more severe at presentation (6.5% vs. 4.5%, ASD = 8.8%) and more disabilities at discharge (34.9% vs 30.5%, ASD =9.4%). However, all sex-related differences in outcomes were attenuated to null after risk adjustments (ASDs<2%). CONCLUSIONS: Compared to male patients, female patients had more vascular risk factors and received similar in-hospital care. They had strokes that were more severe at presentation and more disabilities at discharge, both of which may be explained by worse vascular risk profiles.

Racial differences in persistence to secondary prevention medication regimens after ischemic stroke.

BACKGROUND: Prior stroke is one of the biggest risk factors for future stroke events. Effective secondary prevention medication regimens can dramatically reduce recurrent stroke risk. Guidelines recommend the use of antithrombotic, antihypertensive and lipid-lowering medications after stroke. Medication adherence is known to be better in the presence of a caregiver but long-term adherence after stroke is unknown and disparities may persist. METHODS: We examined the effects of race and sex on baseline prescription and maintenance of secondary prevention regimens in the presence of a caregiver using the Caring for Adults Recovering from the Effects of Stroke (CARES) study, an ancillary study of the national REasons for Geographic and Racial Differences in Stroke (REGARDS). RESULTS: Incident ischemic stroke survivors (N = 172; 36% Black) with family caregivers had medications recorded at hospital discharge and on average 9.8 months later during a home visit. At discharge, antithrombotic prescription (95.9%), lipid-lowering medications (78.8%) and antihypertensives (89.9%) were common and there were no race or sex differences in discharge prescription rates. One year later, medication persistence had fallen to 86.6% for antithrombotics (p = 0.002) and 69.8% for lipid lowering (p = 0.008) but increased to 93.0% for antihypertensives (p = 0.30). Blacks were more likely to have discontinued antithrombotics than Whites (18.3% v 7.7%, p = 0.04). No significant differences in persistence were seen with age, sex, income, depression, or cognitive impairment. CONCLUSIONS: Medication persistence was high in this sample, likely due to the presence of a caregiver. In our cohort, despite similar prescription rates at the time of hospital discharge, Black stroke survivors were more than twice as likely to stop antithrombotics than Whites. The effect of changes in patterns of medication usage on health outcomes in Black stroke survivors warrants continued investigation.

Estimated Global Proportions of Individuals With Persistent Fatigue, Cognitive, and Respiratory Symptom Clusters Following Symptomatic COVID-19 in 2020 and 2021.

Importance: Some individuals experience persistent symptoms after initial symptomatic SARS-CoV-2 infection (often referred to as Long COVID). Objective: To estimate the proportion of males and females with COVID-19, younger or older than 20 years of age, who had Long COVID symptoms in 2020 and 2021 and their Long COVID symptom duration. Design, Setting, and Participants: Bayesian meta-regression and pooling of 54 studies and 2 medical record databases with data for 1.2 million individuals (from 22 countries) who had symptomatic SARS-CoV-2 infection. Of the 54 studies, 44 were published and 10 were collaborating cohorts (conducted in Austria, the Faroe Islands, Germany, Iran, Italy, the Netherlands, Russia, Sweden, Switzerland, and the US). The participant data were derived from the 44 published studies (10 501 hospitalized individuals and 42 891 nonhospitalized individuals), the 10 collaborating cohort studies (10 526 and 1906), and the 2 US electronic medical record databases (250 928 and 846 046). Data collection spanned March 2020 to January 2022. Exposures: Symptomatic SARS-CoV-2 infection. Main Outcomes and Measures: Proportion of individuals with at least 1 of the 3 self-reported Long COVID symptom clusters (persistent fatigue with bodily pain or mood swings; cognitive problems; or ongoing respiratory problems) 3 months after SARS-CoV-2 infection in 2020 and 2021, estimated separately for hospitalized and nonhospitalized individuals aged 20 years or older by sex and for both sexes of nonhospitalized individuals younger than 20 years of age. Results: A total of 1.2 million individuals who had symptomatic SARS-CoV-2 infection were included (mean age, 4-66 years; males, 26%-88%). In the modeled estimates, 6.2% (95% uncertainty interval [UI], 2.4%-13.3%) of individuals who had symptomatic SARS-CoV-2 infection experienced at least 1 of the 3 Long COVID symptom clusters in 2020 and 2021, including 3.2% (95% UI, 0.6%-10.0%) for persistent fatigue with bodily pain or mood swings, 3.7% (95% UI, 0.9%-9.6%) for ongoing respiratory problems, and 2.2% (95% UI, 0.3%-7.6%) for cognitive problems after adjusting for health status before COVID-19, comprising an estimated 51.0% (95% UI, 16.9%-92.4%), 60.4% (95% UI, 18.9%-89.1%), and 35.4% (95% UI, 9.4%-75.1%), respectively, of Long COVID cases. The Long COVID symptom clusters were more common in women aged 20 years or older (10.6% [95% UI, 4.3%-22.2%]) 3 months after symptomatic SARS-CoV-2 infection than in men aged 20 years or older (5.4% [95% UI, 2.2%-11.7%]). Both sexes younger than 20 years of age were estimated to be affected in 2.8% (95% UI, 0.9%-7.0%) of symptomatic SARS-CoV-2 infections. The estimated mean Long COVID symptom cluster duration was 9.0 months (95% UI, 7.0-12.0 months) among hospitalized individuals and 4.0 months (95% UI, 3.6-4.6 months) among nonhospitalized individuals. Among individuals with Long COVID symptoms 3 months after symptomatic SARS-CoV-2 infection, an estimated 15.1% (95% UI, 10.3%-21.1%) continued to experience symptoms at 12 months. Conclusions and Relevance: This study presents modeled estimates of the proportion of individuals with at least 1 of 3 self-reported Long COVID symptom clusters (persistent fatigue with bodily pain or mood swings; cognitive problems; or ongoing respiratory problems) 3 months after symptomatic SARS-CoV-2 infection.

Assessment of hearing and vision impairment in cohort studies collecting cognitive data in older adults.

INTRODUCTION: There are no standard practices for considering sensory impairment in studies measuring cognitive function among older adults. Exclusion of participants with impairments may inaccurately estimate the prevalence of cognitive impairment and dementia. METHODS: We surveyed prospective cohort studies measuring cognitive function in older adults, determined the proportion that excluded participants based on sensory impairment and the proportion that assessed each type of sensory impairment, and described the methods of sensory assessment. RESULTS: Investigators/staff from 85 (of 192 cohorts) responded; 6 (7%) excluded participants with severe impairment; 80 (94%) measured hearing and/or vision impairment, while 5 (6%) measured neither. Thirty-two (38%) cohorts assessed hearing objectively and 45 (53%) assessed vision objectively. DISCUSSION: Findings indicate variation in methods used to assess sensory impairment, with potential implications for resource allocation. To ensure equitable inclusion of study participants, consensus is needed on best practices standardized protocols for assessment and accommodations of sensory impairment.

Change in Life's Simple 7 Measure of Cardiovascular Health After Incident Stroke: The REGARDS Study.

BACKGROUND AND PURPOSE: Life's Simple 7 (LS7) is a metric for cardiovascular health based on the 7 domains of smoking, diet, physical activity, body mass index, blood pressure, total cholesterol, and fasting glucose. Because they may be targeted for secondary prevention purposes, we hypothesized that stroke survivors would experience improvement in LS7 score over time compared with people who did not experience a stroke. We addressed this hypothesis in the REGARDS study (Reasons for Geographic and Racial Differences in Stroke) cohort of Black and White adults enrolled between 2003 and 2007. METHODS: Participants who had LS7 data at baseline, were stroke-free at baseline, had a 10-year follow-up visit, and either did not have a stroke or had an ischemic stroke >1 year before follow-up were included (N=7569). Among these participants, 149 (2.0%) had an adjudicated ischemic stroke between the LS7 assessments. LS7 scores were classified as 0 to 2 points for each domain for a maximum score of 14, with higher scores representing better health. Multivariable linear regression was used to test the association of ischemic stroke with change in LS7 score. Covariates included baseline LS7 score, age, race, sex, education, and geographic region. RESULTS: The 149 stroke survivors had an average of 4.9 years (SD=2.5) of follow-up from the stroke event to the second LS7 assessment. After adjusting for covariates, participants who experienced an ischemic stroke showed 0.28 points more decline in total LS7 score (P=0.03) than those who did not experience a stroke. CONCLUSIONS: Stroke survivors did not experience improvements in cardiovascular health due to secondary prevention after ischemic stroke. On the contrary, they experienced significantly greater decline, indicating the need for greater efforts in secondary prevention after a stroke.

Barriers to medication adherence in a rural-urban dual economy: a multi-stakeholder qualitative study.

BACKGROUND: One of the most cost-effective treatments for secondary prevention of stroke and other non-communicable diseases is a long-term medication regimen. However, the complexities of medication adherence extend far beyond individual behavior change, particularly in low- and middle-income countries. The purpose of this study was to examine stakeholder perspectives on barriers to medication adherence for stroke patients in Beijing, China, identifying opportunities to improve care and policy in resource-constrained settings. METHODS: We conducted a qualitative, phenomenological analysis of data obtained from 36 individuals. Participants were patients; caregivers; healthcare providers; and representatives from industry and government, purposively selected to synthesize multiple perspectives on medication management and adherence for stroke secondary prevention in Beijing, China. Data was analyzed by thematic analysis across iterative coding cycles. RESULTS: Four major themes characterized barriers on medication adherence, across stakeholders and geographies: limitations driven by individual patient knowledge / attitudes; lack of patient-provider interaction time; lack of coordination across the stratified health system; and lack of affordability driven by high overall costs and limited insurance policies. CONCLUSIONS: These barriers to medication management and adherence suggest opportunities for policy reform and local practice changes, particularly for multi-tiered health systems. Findings from this study in Beijing, China could be explored for applicability in other low- and middle-income countries with urban centers serving large geographic regions.

Recovery experiences of younger stroke survivors who are parents: A qualitative content analysis.

AIMS AND OBJECTIVES: To explore the experience of parenting for younger stroke survivors (aged 18 to 64 years at the time of the stroke). BACKGROUND: Stroke among younger adults increased 43% between 2000 and 2010. The social, emotional and physical functioning of younger adults affects multiple aspects of their lives including parenting. There is limited research on the experience of parenting after stroke. DESIGN: This is a qualitative descriptive study. METHODS: We conducted individual semi-structured interviews with 10 younger adults who were actively parenting children under the age of 18 years at the time of stroke. Conventional content analysis was used to analyse the data. We report the methods and results using the COREQ checklist. RESULTS: Impairments from stroke disrupted participants' identity, relationships and roles as a parent. The degree to which parenting abilities and behaviours were affected by stroke was contingent upon the type and severity of impairments as well as the children's age. Participants also observed emotional and behavioural changes in their children in response to their stroke. Support from family, friends, healthcare providers and children's school/day care was crucial to participants throughout their stroke recovery. Two major themes emerged: (a) finding a new normal; and (b) support for parenting post-stroke. CONCLUSIONS: Findings enable a deeper understanding of the distinct parenting challenges younger stroke survivors face and can inform future research on this population. RELEVANCE FOR CLINICAL PRACTICE: Study findings highlight the need for continual and tailored follow-up by nurses and other allied healthcare professionals to decrease the difficulty stroke survivors experience when trying to resume their role as parents.

Depressive Symptoms After Ischemic Stroke: Population-Based Comparisons of Patients and Caregivers With Matched Controls.

Background and Purpose- Persistent depression after ischemic stroke is common in stroke survivors and may be even higher in family caregivers, but few studies have examined depressive symptom levels and their predictors in patient and caregiver groups simultaneously. Methods- Stroke survivors and their family caregivers (205 dyads) were enrolled from the national REGARDS study (Reasons for Geographic and Racial Differences in Stroke) into the CARES study (Caring for Adults Recovering from the Effects of Stroke) ≈9 months after a first-time ischemic stroke. Demographically matched stroke-free dyads (N=205) were also enrolled. Participants were interviewed by telephone, and depressive symptoms were assessed with the 20-item Center for Epidemiological Studies-Depression scale. Results- Significant elevations in depressive symptoms (Ps<0.03) were observed for stroke survivors (M=8.38) and for their family caregivers (M=6.42) relative to their matched controls (Ms=5.18 and 4.62, respectively). Stroke survivors reported more symptoms of depression than their caregivers (P=0.008). No race or sex differences were found, but differential prediction of depressive symptom levels was found across patients and caregivers. Younger age and having an older caregiver were associated with more depressive symptoms in stroke survivors while being a spouse caregiver and reporting fewer positive aspects of caregiving were associated with more depressive symptoms in caregivers. The percentage of caregivers at risk for clinically significant depression was lower in this population-based sample (12%) than in previous studies of caregivers from convenience or clinical samples. Conclusions- High depressive symptom levels are common 9 months after first-time ischemic strokes for stroke survivors and family caregivers, but rates of depressive symptoms at risk for clinical depression were lower for caregivers than previously reported. Predictors of depression differ for patients and caregivers, and standards of care should incorporate family caregiving factors.

Use of Emergency Medical Services and Timely Treatment Among Ischemic Stroke.

Background and Purpose- Emergency medical services (EMSs) are critical for early treatment of patients with ischemic stroke, yet data on EMS utilization and its association with timely treatment in China are still limited. Methods- We examined data from the Chinese Stroke Center Alliance for patients with ischemic stroke from June 2015 to June 2018. Absolute standardized difference was used for covariates' balance assessments. We used multivariable logistic models with the generalized estimating equations to account for intrahospital clustering in identifying demographic and clinical factors associated with EMS use as well as in evaluating the association of EMS use with timely treatment. Results- Of the 560 447 patients with ischemic stroke analyzed, only 69 841 (12.5%) were transported by EMS. Multivariable-adjusted results indicated that those with younger age, lower levels of education, less insurance coverage, lower income, lower stroke severity, hypertension, diabetes mellitus, and peripheral vascular disease were less likely to use EMS. However, a history of cardiovascular diseases was associated with increased EMS usage. Compared with self-transport, EMS transport was associated with significantly shorter onset-to-door time, door-to-needle time (if prenotification was sent), earlier arrival (adjusted odds ratio [95% CIs] were 2.07 [1.95-2.20] for onset-to-door time ≤2 hours, 2.32 [2.18-2.47] for onset-to-door time ≤3.5 hours), and more rapid treatment (2.96 [2.88-3.05] for IV-tPA [intravenous recombinant tissue-type plasminogen activator] in eligible patients, 1.70 [1.62-1.77] for treatment with IV-tPA by 3 hours if onset-to-door time ≤2 hours, and 1.76 [1.70-1.83] for treatment with IV-tPA by 4.5 hours if onset-to-door time ≤3.5 hours). Conclusions- Although EMS transportation is associated with substantial reductions in prehospital delay and improved likelihood of early arrival and timely treatment, rate of utilization is currently low among Chinese patients with ischemic stroke. Developing an efficient EMS system and promoting culture-adapted education efforts are necessary for improving EMS activation.

Atrial Fibrillation Known Before or Detected After Stroke Share Similar Risk of Ischemic Stroke Recurrence and Death.

Background and Purpose- We aim to compare the risk of 1-year ischemic stroke recurrence and death for atrial fibrillation diagnosed after stroke (AFDAS), atrial fibrillation known before stroke (KAF), and sinus rhythm (SR). Methods- From June 2012 to January 2013, 19 604 patients with acute ischemic stroke were admitted to 219 urban hospitals in the China National Stroke Registry II. Based on heart rhythm assessed during admission, we classified patients as AFDAS, KAF, or SR. We explored the relationship between heart rhythm groups and 1-year ischemic stroke recurrence or death by using Cox regression adjusted for multiple covariates. Considering that death is a competing risk for stroke recurrence, we used the competing risks analysis of Fine and Gray and subdistribution Cox proportional hazards to test the association between heart rhythm and 1-year outcomes. Results- Among 19 604 ischemic stroke patients, 17 727 had SR, 495 AFDAS, and 1382 KAF. At 1 year, 54 (10.9%) patients with AFDAS, 182 (13.2%) with KAF, and 1008 (5.7%) with SR had recurrent ischemic strokes ( P<0.0001). Mortality was 22.0% in patients with AFDAS, 22.1% in patients with KAF, and 7.0% in patients with SR ( P<0.0001). AFDAS-related ischemic stroke recurrence adjusted risk was higher than that of SR (adjusted subdistribution hazard ratios, 1.61; 95% CI, 1.29-2.01) but not different from that of KAF (adjusted subdistribution hazard ratio, 1.12; 95% CI, 0.87-1.45]). The adjusted risk of 1-year death for AFDAS was also higher than that of SR (hazard ratio, 1.70; 95% CI, 1.37-2.12) and not different from that of KAF (hazard ratio, 1.10; 95% CI, 0.86-1.41). Conclusions- This study showed that AFDAS had similar risk of 1-year ischemic stroke recurrence and mortality when compared with KAF and higher risk when compared with SR. The potential risk of AFDAS should be given more emphasis, and appropriate treatment is needed to achieve reduction in the incidence of stroke recurrence and mortality.

Orthostatic Blood Pressure Change, Dizziness, and Risk of Dementia in the ARIC Study.

BACKGROUND: Abnormal orthostatic blood pressure (BP) regulation may result in cerebral hypoperfusion and brain ischemia and contribute to dementia. It may also manifest as early symptoms of the neurodegenerative process associated with dementia. The relationship between the magnitude and timing of orthostatic BP responses and dementia risk is not fully understood. METHODS: We conducted a prospective cohort analysis of the associations of orthostatic BP changes and self-reported orthostatic dizziness with the risk of dementia in the Atherosclerosis Risk in Communities study (ARIC). We calculated changes in BP from the supine to the standing position at 5 measurements taken within 2 minutes after standing during the baseline visit (1987-1989). The primary outcome was adjudicated dementia ascertained through 2019. RESULTS: Among 11 644 participants (mean [SD] age, 54.5 [5.7] years; 54.1% women; 25.9% Black), 2303 dementia cases were identified during a median follow-up of 25.9 years. Large decreases in systolic BP from the supine to standing position measured at the first 2 measurements ≈30 and 50 seconds after standing, but not afterward, were associated with orthostatic dizziness and a higher risk of dementia. Comparing a decrease in systolic BP of ≤-20 or >-20 to -10 mm Hg to stable systolic BP (>-10 to 10 mm Hg) at the first measurement, the adjusted hazard ratios were 1.22 (95% CI, 1.01-1.47) and 1.10 (95% CI, 0.97-1.25), respectively. CONCLUSIONS: Abnormal orthostatic BP regulation, especially abrupt drops in BP within the first minute, might be early risk markers for the development of dementia. Transient early orthostatic hypotension warrants more attention in clinical settings.

Social relationships, amyloid burden, and dementia: The ARIC-PET study.

INTRODUCTION: This study aimed to assess whether social relationships in mid-life reduce the risk of dementia related to amyloid burden. METHODS: Participants in the Atherosclerosis Risk in Communities (ARIC) study were assessed for social support and isolation (visit 2; 1990-1992). A composite measure, "social relationships," was generated. Brain amyloid was evaluated with florbetapir positron emission tomography (PET); (visit 5; 2012-2014). Incident dementia cases were identified following visit 5 through 2019 using ongoing surveillance. Relative contributions of mid-life social relationships and elevated brain amyloid to incident dementia were evaluated with Cox regression models. RESULTS: Among 310 participants without dementia, strong mid-life social relationships were associated independently with lower dementia risk. Elevated late-life brain amyloid was associated with greater dementia risk. DISCUSSION: Although mid-life social relationships did not moderate the relationship between amyloid burden and dementia, these findings affirm the importance of strong social relationships as a potentially protective factor against dementia.

The association of long-term exposure to criteria air pollutants, fine particulate matter components, and airborne trace metals with late-life brain amyloid burden in the Atherosclerosis Risk in Communities (ARIC) study.

BACKGROUND: Studies suggest associations between long-term ambient air pollution exposure and outcomes related to Alzheimer's disease (AD). Whether a link exists between pollutants and brain amyloid accumulation, a biomarker of AD, is unclear. We assessed whether long-term air pollutant exposures are associated with late-life brain amyloid deposition in Atherosclerosis Risk in Communities (ARIC) study participants. METHODS: We used a chemical transport model with data fusion to estimate ambient concentrations of PM2.5 and its components, NO2, NOx, O3 (24-hour and 8-hour), CO, and airborne trace metals. We linked concentrations to geocoded participant addresses and calculated 10-year mean exposures (2002 to 2011). Brain amyloid deposition was measured using florbetapir amyloid positron emission tomography (PET) scans in 346 participants without dementia in 2012-2014, and we defined amyloid positivity as a global cortical standardized uptake value ratio ≥ the sample median of 1.2. We used logistic regression models to quantify the association between amyloid positivity and each air pollutant, adjusting for putative confounders. In sensitivity analyses, we considered whether use of alternate air pollution estimation approaches impacted findings for PM2.5, NO2, NOx, and 24-hour O3. RESULTS: At PET imaging, eligible participants (N = 318) had a mean age of 78 years, 56% were female, 43% were Black, and 27% had mild cognitive impairment. We did not find evidence of associations between long-term exposure to any pollutant and brain amyloid positivity in adjusted models. Findings were materially unchanged in sensitivity analyses using alternate air pollution estimation approaches for PM2.5, NO2, NOx, and 24-hour O3. CONCLUSIONS: Air pollution may impact cognition and dementia independent of amyloid accumulation, though whether air pollution influences AD pathogenesis later in the disease course or at higher exposure levels deserves further consideration.

Temporal trends and rural-urban disparities in cerebrovascular risk factors, in-hospital management and outcomes in ischaemic strokes in China from 2005 to 2015: a nationwide serial cross-sectional survey.

BACKGROUND: Stroke is the leading cause of mortality in China, with limited evidence of in-hospital burden obtained from nationwide surveys. We aimed to monitor and track the temporal trends and rural-urban disparities in cerebrovascular risk factors, management and outcomes from 2005 to 2015. METHODS: We used a two-stage random sampling survey to create a nationally representative sample of patients admitted for ischaemic stroke in 2005, 2010 and 2015. We sampled participating hospitals with an economic-geographical region-stratified random-sampling approach first and then obtained patients with a systematic sampling approach. We weighed our survey data to estimate the national-level results and assess changes from 2005 to 2015. RESULTS: We analysed 28 277 ischaemic stroke admissions from 189 participating hospitals. From 2005 to 2015, the estimated national hospital admission rate for ischaemic stroke per 100 000 people increased (from 75.9 to 402.7, Ptrend<0.001), and the prevalence of risk factors, including hypertension, diabetes, dyslipidaemia and current smoking, increased. The composite score of diagnostic tests for stroke aetiology assessment (from 0.22 to 0.36, Ptrend<0.001) and secondary prevention treatments (from 0.46 to 0.70, Ptrend<0.001) were improved. A temporal decrease was found in discharge against medical advice (DAMA) (from 15.2% (95% CI 13.7% to 16.7%) to 8.6% (8.1% to 9.0%); adjusted Ptrend=0.046), and decreases in in-hospital mortality (0.7% in 2015 vs 1.8% in 2005; adjusted OR (aOR) 0.52; 95% CI 0.32 to 0.85) and the composite outcome of in-hospital mortality or DAMA (8.4% in 2015 vs 13.9% in 2005; aOR 0.65; 95% CI 0.47 to 0.89) were observed. Disparities between rural and urban hospitals narrowed; however, disparities persisted in in-hospital management (brain MRI: rural-urban difference from -14.4% to -11.2%; cerebrovascular assessment: from -20.3% to -16.7%; clopidogrel: from -2.1% to -10.3%; anticoagulant for atrial fibrillation: from -10.9% to -8.2%) and in-hospital outcomes (DAMA: from 2.7% to 5.0%; composite outcome of in-hospital mortality or DAMA: from 2.4% to 4.6%). CONCLUSIONS: From 2005 to 2015, improvements in hospital admission and in-hospital management for ischaemic stroke in China were found. A temporal improvement in DAMA and improvements in in-hospital mortality and the composite outcome of in-hospital mortality or DAMA were observed. Disparities between rural and urban hospitals generally narrowed but persisted.

Eliminating racial disparities in dementia risk by equalizing education quality: A sensitivity analysis.

BACKGROUND: Higher risk of dementia among racial/ethnic minorities compared to White populations in the U.S. has been attributed to life-course exposures to adverse conditions such as lower educational attainment, but most studies have not considered additional disparities in education quality. We sought to determine the extent to which disparities in dementia would be reduced had different racial groups received the same quality of education, with no change to present disparities in educational attainment. METHODS: We conducted a literature review to assess whether and how measures of educational attainment and quality are utilized in the development of norms for standard cognitive screening measures. In a separate search of the literature, we identified estimates of relationships between race, education quality and dementia; and calculated the adjusted association between race and dementia had education quality been equalized between Black and White participants. RESULTS: Most norms for cognitive measures included educational attainment, but few addressed quality. Our search identified relevant parameter estimates: 44.3% of Black participants and 10.5% of White participants had "limited literacy" (<9th grade reading level, a potential marker of poor education quality), which was associated with a 53% greater hazard of dementia compared with "adequate literacy" (≥ 9th grade reading level) after adjusting for educational attainment. Applying these parameters to a hazard ratio of 1.37 (95%CI: 1.12,1.67) for the risk of dementia comparing Black to White participants, we obtained an adjusted hazard ratio of 1.17 (0.96,1.43), a 54% reduction. DISCUSSION: Present studies are limited in their consideration of education quality. Our work using available measures from the literature suggests that if education quality were equalized across groups by race, without changing disparities in attainment, racial disparities in dementia would be reduced by about half. Future work should seek to consistently incorporate education quality in order to better understand the sources of disparities.

Pre-stroke dementia and in-hospital outcomes in the Chinese Stroke Center Alliance.

Background: Little is known about the impact of prevalent dementia on in-hospital outcomes of patients with incident stroke in China. Using data from the Chinese Stroke Center Alliance (CSCA), we aim to quantify the prevalence of pre-stroke dementia and whether this group is at higher risk of adverse in-hospital outcomes compared to those without pre-stroke dementia. Methods: We used multivariable logistic regression models to assess the associations between pre-stroke dementia and ambulation by day 2, in-hospital mortality, in-hospital complications, and being discharged home. Covariates included age, sex, comorbidities [dyslipidemia, atrial fibrillation, peripheral vascular disease (PVD), smoking, and alcohol use], medication history (antiplatelet drugs or lipid-lowering drugs), stroke severity [measured by the National Institute of Health Stroke Scale (NIHSS)], administration of intravenous tissue plasminogen activator (IV tPA) within 4.5 hours of stroke onset, and receipt of deep vein thrombosis (DVT) prophylaxis if indicated. Results: In the final analytic sample of 559,070 ischemic stroke patients with no prior stroke history enrolled across 1,476 hospitals, those with pre-stroke dementia (n=1,511; 0.3%) were older and more likely to be female. Despite having received similar treatment, patients with pre-stroke dementia had lower odds of ambulating by day 2 [odds ratio (OR) =0.69; 95% confidence interval (CI): 0.62-0.78], higher odds of in-hospital mortality (OR =2.01; 95% CI: 1.35-2.99) or complications (OR =2.17; 95% CI: 1.93-2.44), and lower odds of being discharged home compared to those without pre-stroke dementia (OR =0.71; 95% CI: 0.62-0.83). Conclusions: Worse in-hospital outcomes among patients with pre-stroke dementia may be explained by pre-existing cognitive impairment that limited their ability to advocate for care needs. Further research is needed to determine whether a different care pathway or additional attention from clinicians is necessary for patients with pre-stroke dementia.