The role of sirtuins and uncoupling proteins on vascular aging: The Northern Manhattan Study experience

Aging affects all organs. Arteries, in particular, are among the most affected. Vascular aging (VA) is defined as age-associated changes in function and structure of vessels. Classical VA phenotypes are carotid intima-media thickness (IMT), carotid plaque (CP), and arterial stiffness (STIFF). Individuals have different predisposition to these VA phenotypes and their associated risk of cardiovascular events. Some develop an early vascular aging (EVA), and others are protected and identified as having supernormal vascular aging (SUPERNOVA). The mechanisms leading to these phenotypes are not well understood. In the Northern Manhattan Study (NOMAS), we found genetic variants in the 7 Sirtuins (SIRT) and 5 Uncoupling Proteins (UCP) to be differently associated with risk to developing VA phenotypes. In this article, we review the results of genetic-epidemiology studies to better understand which of the single nucleotide polymorphisms (SNPs) in SIRT and UCP are responsible for both EVA and SUPERNOVA.

Relationships of Hematocrit With Chronic Covert and Acute Symptomatic Lacunar Ischemic Lesions

BACKGROUND AND OBJECTIVES

Red blood cell (RBC) concentrations are known to associate with ischemic stroke. It is unclear whether RBC concentrations associate specifically with small vessel disease lacunar infarcts. We investigated the hypothesis that RBC concentrations associate with both chronic covert and acute symptomatic brain MRI lacunar infarcts.

METHODS

A cross-sectional observational analysis was performed across 2 cohorts with available hematocrit (as the assessment of RBC concentration exposure) and MRI outcome data. The primary setting was a population-based cohort of stroke-free, older adult (>50 years) participants from the Northern Manhattan Study (NOMAS) enrolled between 2003 and 2009. A second replication sample consisted of patients admitted with acute stroke and enrolled into the Columbia Stroke Registry (CSR) between 2005 and 2020. Associations of hematocrit with (1) chronic, covert lacunar infarcts and (2) symptomatic (i.e., acute) lacunar strokes were separately assessed from the NOMAS and CSR cohorts, respectively, using general additive models after adjusting for relevant covariates.

RESULTS

Of 1,218 NOMAS participants analyzed, 6% had chronic, covert lacunar infarcts. The association between hematocrit and these covert lacunar infarcts was U-shaped (χ2 = 9.21 for nonlinear associations; p = 0.03), with people with hematocrit extremes being more likely to have covert lacunar infarcts. Of the 1,489 CSR patients analyzed, 23% had acute lacunar strokes. In this sample, only the relationships of increased hematocrit concentrations and lacunar strokes were replicated (adjusted coefficient β = 0.020; SE = 0.009; p = 0.03).

DISCUSSION

We identified relationships of hematocrit with MRI lacunar infarcts in both stroke-free and ischemic stroke cohorts, respectively. The relationship between increased hematocrit concentrations with lacunar infarcts was replicated in both cohorts. Further studies are required to clarify the mechanisms behind the relationships of hematocrit with ischemic cerebral small vessel disease.

Racial and Ethnic Differences in the Risk of Ischemic Stroke After Nontraumatic Intracerebral Hemorrhage

BACKGROUND

Intracerebral hemorrhage (ICH) is associated with an increased risk of ischemic stroke. Whether there are racial and ethnic disparities in the risk of ischemic stroke after ICH is poorly understood. We therefore aimed to test the hypothesis that non-Hispanic Black and Hispanic ICH patients have a higher risk of ischemic stroke compared with non-Hispanic White ICH patients.

METHODS

We performed a retrospective cohort study using the Healthcare Cost and Utilization Project (HCUP) on all hospitalizations at all nonfederal hospitals in Florida from 2005 to 2018 and New York from 2006 to 2016. Race and ethnicity were coded as a single variable in HCUP. We included patients with an ICH, and without a prior or concomitant diagnosis of ischemic stroke, ascertained using validated International Classification of Diseases-Clinical Modification-9 and 10 diagnosis codes. Using Cox proportional hazard models, we studied the relationship between race and risk of ischemic stroke starting from the time of discharge from ICH hospitalization, after adjustment of demographics and vascular comorbidities.

RESULTS

We included 91 342 patients with ICH-62% non-Hispanic White, 18% non-Hispanic Black, and 12% Hispanic patients. Non-Hispanic Black and Hispanic patients were younger and had a higher prevalence of cardiovascular comorbidities; however, atrial fibrillation was more prevalent among non-Hispanic White patients. During a median follow-up period of 4.4 years (interquartile range, 1.5-8.1), an incident ischemic stroke occurred in 3377 (6%) non-Hispanic White, 1323 (8%) non-Hispanic Black, and 844 (8%) Hispanic patients. In adjusted Cox models, the risk of an ischemic stroke was significantly higher among non-Hispanic Black patients (hazard ratio, 1.6 [95% CI, 1.5-1.8]) and Hispanic patients (hazard ratio, 1.4 [95% CI, 1.3-1.5]), compared with non-Hispanic White patients. Similar results were obtained in sensitivity analyses when using death as a competing risk and after excluding patients with atrial fibrillation and valvular heart disease.

CONCLUSIONS

In a large heterogeneous cohort of patients with ICH, we found that non-Hispanic Black and Hispanic patients had a significantly higher risk of ischemic stroke compared with non-Hispanic White patients.

Abstract 161: Racial And Ethnic Differences In The Risk Of Ischemic Stroke After Intracerebral Hemorrhage

Background: Intracerebral hemorrhage (ICH) is associated with an increased risk of ischemic stroke. Whether there are racial and ethnic disparities in the risk of ischemic stroke after ICH is poorly understood.

Hypothesis: Non-Hispanic Black and Hispanic ICH patients have a higher risk of ischemic stroke compared to White ICH patients.

Methods: We retrospectively analyzed data from the Healthcare Cost and Utilization Project on all hospitalizations at all nonfederal hospitals in Florida from 2005 to 2018 and New York from 2006 to 2016. We included patients with an ICH, and without a prior or concomitant diagnosis of ischemic stroke. ICH and ischemic stroke were ascertained using validated ICD-9-CM and ICD-10-CM codes. Using Cox proportional hazard models, we studied the relationship between race and risk of ischemic stroke, after adjustment of demographics and comorbidities.

Results: We included 55,582 patients with ICH- 66% Non-Hispanic White, 19% Non-Hispanic Black, and 13% Hispanic. Black and Hispanic patients were younger and had a higher prevalence of cardiovascular comorbidities; however, atrial fibrillation was more prevalent among White patients. During a median follow up period of 3.6 years (IQR 0.7-7.2), an incident ischemic stroke occurred in 3,361 (9%) Non-Hispanic White, 1,308 (12%) Non-Hispanic Black, and 858 (12%) Hispanic patients (p<.001). In adjusted Cox models, the risk of an ischemic stroke was significantly higher among Non-Hispanic Black patients (HR 1.6; 95% CI,1.4-1.7) and Hispanic patients (HR 1.4; 95% CI,1.2-1.5]), compared to non-Hispanic White patients.

Conclusions: Among patients with ICH, Non-Hispanic Black and Hispanic patients had a significantly higher risk of ischemic stroke compared to Non-Hispanic White patients.

Abstract WP188: Relationships Of Hematocrit With Asymptomatic And Symptomatic Lacunar Ischemic Lesions

Introduction: Hematocrit at both low and high extremes can result in both hypoxia and thrombosis respectively. While both scenarios may predispose to ischemia, it is unclear whether hematocrit associates with small vessel cerebrovascular lacunar infarcts.

Hypothesis: Hematocrit levels will associate with both asymptomatic and symptomatic cerebrovascular lacunar infarcts in stroke-free participants and ischemic stroke patients, respectively.

Methods: A cross sectional observational analysis of a prospective, population-based cohort study of stroke-free, older adult (>50) participants from the Northern Manhattan study (NOMAS) receiving baseline hematocrit testing and MRI between 2003-2008 were analyzed. A second, single center prospective cohort of admitted adult ischemic stroke patients receiving baseline hematocrit testing and MRI between 2005-2018 was evaluated. Associations of hematocrit with covert, asymptomatic chronic lacunar infarcts from stroke-free participants in NOMAS were assessed using general additive models after adjusting for relevant covariates. Separate analyses were performed to assess associations of hematocrit with symptomatic acute lacunar infarct stroke etiology using similar adjusted models for patients admitted and enrolled into the ischemic stroke registry.

Results: Of 1218 NOMAS participants analyzed, 6% had covert chronic lacunar infarcts. The association between hematocrit and covert chronic lacunar infarcts was U-shaped (X2: 9.21; p-value: 0.03). In the 1489 patients from the ischemic stroke registry, 23% were identified to have symptomatic acute lacunar infarcts. Linear relationships were identified with higher hematocrit and symptomatic acute lacunar infarct etiology (adjusted coefficient beta: 0.020; standard error: 0.009; p=0.03).

Conclusions: We identified relationships of hematocrit with both asymptomatic and symptomatic lacunar infarcts in both stroke-free and ischemic stroke cohorts, respectively. There may be a relevant role of red blood cell volumes with ischemic cerebral small vessel disease pathophysiology. However, further studies are required to clarify the mechanisms behind these relationships.

Internal Carotid Artery Angle Variations are Poorly Explained by Vascular Risk Factors: The Northern Manhattan Study

OBJECTIVES

The internal carotid artery (ICA) angle of origin may contribute to atherogenesis by altered hemodynamics. We aim to determine the contribution of vascular risk factors and arterial wall changes to ICA angle variations.

METHODS

We analyzed 1,065 stroke-free participants from the population-based Northern Manhattan Study who underwent B-mode ultrasound (mean age 68.7±8.9 years; 59% women). ICA angle was estimated at the intersection between the common carotid artery and the ICA center line projections. Narrower external angles translating into greater carotid bifurcation bending were considered unfavorable. Linear regression models were fitted to assess the relationship between ICA angle and demographics, vascular risk factors, and arterial wall changes including carotid intima-media thickness (cIMT) and plaque presence.

RESULTS

ICA angles were narrower on the left compared to the right side (153±15.4 degrees versus 161.4±12.7 degrees, p<0.01). Mean cIMT was 0.9±0.1 mm and 54.3% had at least one plaque. ICA angle was not associated with cIMT or plaque presence. Unfavorable left and right ICA angles were associated with advanced age (per 10-year increase β=-1.6; p=0.01, and -1.3; p=0.03, respectively) and being Black participant (β=-4.6; p<0.01 and -2.9; p=0.04, respectively), while unfavorable left ICA angle was associated with being female (β=-2.8; p=0.03) and increased diastolic blood pressure (per 10 mmHg increase β=-2.1; p<0.01). Overall, studied factors explained less than 10% of the variance in ICA angle (left R2=0.07; right R2=0.05).

CONCLUSION

Only a small portion of ICA angle variation were explained by demographics, vascular risk factors and arterial wall changes. Whether ICA angle is determined by other environmental or genetic factors, and is an independent risk factor for atherogenesis, requires further investigation.

Adherence to Guideline-Recommended Cancer Screening in Stroke Survivors: A Nationwide Analysis

OBJECTIVES

Cancer can present as stroke. Several cancer types have established screening guidelines. We investigated adherence to guideline-recommended cancer screening in stroke survivors versus the general population.

MATERIALS AND METHODS

We performed a cross-sectional analysis using 2012-2018 data from the CDC's Behavioral Risk Factor Surveillance System (BRFSS) survey. BRFSS is a nationally-representative telephone survey of non-institutionalized Americans that collects data about health conditions and behaviors, including cancer screening. We defined guideline-recommended colorectal, lung, and breast cancer screening based on the U.S. Preventive Services Task Force recommendations. We used survey-specific methods to estimate up-to-date screening rates for those with and without prior stroke. We used logistic regression to estimate the odds of up-to-date screening in stroke survivors compared to those without history of stroke after adjustment for potential confounders.

RESULTS

Among 1,018,440 respondents eligible for colorectal cancer screening, 66% were up-to-date. Among 6,880 respondents eligible for lung cancer screening, 16% were up-to-date. Among 548,434 women eligible for breast cancer screening, 78% were up-to-date. After adjustment for demographics and confounders, stroke survivors were more likely to have up-to-date colorectal cancer screening (OR, 1.10; 95% CI, 1.05-1.16), equally likely to undergo lung cancer screening (OR, 0.99; 95% CI, 0.62-1.59), and less likely to undergo breast cancer screening (OR, 0.87; 95% CI, 0.80-0.94).

CONCLUSIONS

In a nationwide analysis, stroke survivors had similar suboptimal adherence to guideline-recommended cancer screening as the general population.

Feasibility of a wearable biosensor device to characterize exercise and sleep in neurology residents

BACKGROUND

Research suggests optimizing sleep, exercise and work-life balance may improve resident physician burnout. Wearable biosensors may allow residents to detect and correct poor sleep and exercise habits before burnout develops. Our objectives were to evaluate the feasibility of a wearable biosensor to characterize exercise/sleep in neurology residents and examine its relationship to self-reported, validated survey measures. We also assessed the device's impact on well-being and barriers to use.

METHODS

This prospective cohort study evaluated the WHOOP Strap 2.0 in neurology residents. Participants completed regular online surveys, including self-reported hours of sleep/exercise, and validated sleep/exercise scales at 3-month intervals. Autonomic, exercise, and sleep measures were obtained from WHOOP. Changes were evaluated over time via linear regression. Survey and WHOOP metrics were compared using Pearson correlations.

RESULTS

Sixteen (72.7%) of 22 eligible participants enrolled. Eleven (68.8%) met the minimum usage requirement (6+ months) and were classified as 'consecutive wearers.' Significant increases were found in sleep duration and exercise intensity. Moderate-to-low correlations were found between survey responses and WHOOP measures. Most (73%) participants reported a positive impact on well-being. Barriers to use included 'Forgetting to wear' (20%) and 'not motivational' (23.3%).

CONCLUSION

Wearable biosensors may be a feasible tool to evaluate sleep/exercise in residents.

Do Carotid Plaque Ulcers Heal? Potential Detection of Carotid Artery Plaque Healing by Carotid Ultrasound Imaging

OBJECTIVES

Carotid plaque ulcers confer an increased risk for stroke/ transient ischemic attacks in both symptomatic and asymptomatic carotid artery stenosis. Little is known about the healing rates of ulcers or the development of new ulcers. Carotid Duplex studies are noninvasive and easily repeatable tests to monitor progression of carotid stenosis and plaque morphology. Our aim was to determine the prevalence and healing rates of ultrasound-detected carotid plaque ulcers.

METHODS

We retrospectively reviewed 5837 carotid Duplex studies performed in an outpatient ultrasound laboratory affiliated with the neurological department of an academic center. A total of 3215 patients underwent a first carotid ultrasound Duplex study, and 2622 follow-up studies were done. Carotid ulcer was defined as a 2 mm deep surface indentation in a carotid plaque with a well-defined back wall, as determined by multimodal ultrasound imaging techniques.

RESULTS

The prevalence of carotid plaque ulcers among the 3215 patients with a first ultrasound study was 3% (82/3215). The mean follow-up was 42 ± 30 months, and the median number of follow-up studies was 6. Among patients with ulcers, follow-up studies were available in 65/82 patients. During the follow-up period, 28/65 (43%) ulcers healed. Among all 2622 follow-up studies, 45 patients developed a new ulcer.

CONCLUSIONS

Duplex-detected carotid plaque ulcer prevalence is low. The carotid ulcers healed in approximately half of patients during follow-up. Factors associated with ulcer healing and development remain poorly understood.

Abstract P641: Risk and Predictors of New Cancer Diagnoses After Acute Ischemic Stroke

Introduction: Acute ischemic stroke (AIS) may be the first sign of occult cancer. We aimed to better define the incidence of cancer in the year after AIS and to identify clinical factors associated with new cancer diagnoses.

Methods: This was a retrospective cohort study using data from the Cornell Acute Stroke Academic Registry (CAESAR) on patients hospitalized at our center with AIS from 2011-2015. Patients with history of cancer were excluded. Through automated electronic data capture and manual abstraction of inpatient and outpatient medical records, we collected data on patients’ demographics, comorbidities, presentation, radiographic characteristics, stroke subtype, and clinical outcomes. Patients were followed for 1 year after the index AIS for a new diagnosis of pathologically-confirmed cancer. Cox hazards regression adjusting for the competing risk of death was used to evaluate associations between clinical factors and incident cancer. Factors significantly associated in multivariable analysis were entered into a risk stratification score, and this score’s discriminatory ability was evaluated by Harrell’s C-statistic.

Results: After excluding 253 patients with history of cancer, this analysis included 963 patients with AIS. During a mean follow-up of 222 days, 16 patients (1.7%; 95% CI, 1.0-2.7%) were diagnosed with cancer. The most common cancers were lung (n=7) and leukemia (n=4) and the median time to cancer diagnosis was 13 days (IQR, 7-194 days). Among patients with cryptogenic stroke, the 1-year cancer incidence rate was 1.7% (95% CI, 0.6-3.7%). Clinical factors associated with incident cancer in multivariable analysis were venous thromboembolism during the AIS hospitalization (HR, 12.5; 95% CI, 3.3-47.0), unexplained weight loss within 6 months (HR 11.7; 95% CI, 3.3-42.0), and three-territory acute infarcts (HR, 4.1, 95% CI, 1.3-13.4). These factors were used to create a clinical score that had a C-statistic of 0.7 (95% CI, 0.5-0.8).

Conclusions: In a large urban cohort of AIS, the estimated 1-year incidence of first-ever cancer was 1.7%. Unexplained weight loss, concomitant venous thromboembolism, and three-territory acute infarction pattern may serve as clues to occult cancer with AIS.

Abstract P671: Association Between Liver Fibrosis and Postoperative Stroke

Introduction: Chronic liver disease is associated with aberrant hemostasis, resulting in an increased risk of clotting and bleeding. We hypothesized that liver fibrosis, a manifestation of progressive chronic liver disease, is associated with stroke among people who have been subjected to the hemostatic stress of surgery.

Methods: We conducted a retrospective, multicenter cohort study using data from 680 hospitals participating in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP), a prospective registry of 30-day outcomes. Quality measures, such as stroke, have been validated and have 95% inter-observer agreement. We included adults who underwent major surgery, except neurosurgery, from 2005-2016. The exposure was the Aspartate aminotransferase to Platelet Ratio Index (APRI) liver fibrosis score, calculated from preoperative aspartate aminotransferase and platelet count. The primary outcome was incident stroke, reported by NSQIP as a composite of ischemic and hemorrhagic stroke. We used multivariable Cox proportional hazards models to assess the relationship between APRI and incident stroke, adjusting for demographics, comorbidities, and surgical characteristics (surgical type and American Society of Anesthesiologists preoperative fitness classification). In a sensitivity analysis, we also adjusted for preoperative platelet count and coagulation indices.

Results: Among 2,729,995 patients, the mean age was 57 (SD, 17) years and 58% were women. A total of 6,886 patients had stroke within 30 days (0.25%). In unadjusted analyses, a 1-point increase in APRI was associated with a 3% increased risk of stroke (HR, 1.03; 95% CI, 1.02-1.03). The association remained significant in models adjusted for comorbidities and surgical characteristics (HR, 1.02; 95% CI, 1.01-1.03). Sensitivity analyses also adjusted for platelet count and coagulation indices were consistent (HR, 1.03; 95% CI, 1.01-1.04).

Conclusions: A liver fibrosis score calculated from routine preoperative laboratory data was independently, albeit modestly, associated with an increased risk of stroke within 30 days after surgery. Whether preoperative assessment of liver disease markers has clinical utility requires investigation.

Measures of Adiposity and Alzheimer's Disease-Related MRI Markers: The Northern Manhattan Study

BACKGROUND

Adiposity may increase risk for dementia and Alzheimer's disease (AD), but mechanisms are unclear.

OBJECTIVE

To examine associations between measures of adiposity with AD-signature region cortical thickness and hippocampal volume.

METHODS

We used data from the Northern Manhattan Study, a clinically stroke-free cohort of mostly Hispanic participants. Exposures of interest included body mass index (BMI), waist-hip-ratio (WHR), waist circumference (WC), and adiponectin concentration, measured at study entry. AD-signature region cortical thickness and hippocampal volume were obtained using Freesurfer. We estimated associations using multivariable linear regression, adjusting for sociodemographics and health behaviors. We re-examined estimates after adjustment for APOEɛ4 allele status or carotid intima-media thickness (cIMT), among those cognitively unimpaired, and after weighting for the inverse probability of selection into the MRI sub-study. We also repeated analyses for cortical thickness in non-AD signature regions.

RESULTS

The sample (N = 947, 63% women, 66% Hispanic/Latino, 26% obese) had a mean (SD) age = 63 (8) years. Greater BMI and WC (both z-scored) were associated with thinner AD-signature region cortex (also z-scored) (BMI: β [95% CI] = -0.09 [-0.18, -0.01], WC: β [95% CI] = -0.11 [-0.20, -0.02]). We did not find evidence that adiposity was related to hippocampal volume. Results were consistent after adjustment for APOEɛ4 allele status or cIMT, after weighting for selection, among those cognitively unimpaired, and for non-AD signature region cortical thickness.

CONCLUSION

Greater BMI and WC were related to cortical thinning within and outside the AD-signature region, suggesting a global effect not specific to AD.

Randomized Trial of Combined Aerobic, Resistance, and Cognitive Training to Improve Recovery From Stroke: Feasibility and Safety

Background Physical exercise and cognitive training have been recommended to improve cognitive outcomes poststroke, but a multifaceted strategy including aerobic, resistance, and cognitive training to facilitate poststroke recovery has not been investigated. We aimed to assess the feasibility, adherence, and safety of a combined aerobic, resistance, and cognitive training intervention (CARET+CTI) after stroke. Methods and Results We prospectively randomized patients presenting with recent stroke to a comparison of a supervised 12-week CARET+CTI program and a control group receiving sham CARET+CTI. Participants were scheduled for 3 weekly CARET and CTI sessions. All participants underwent pre- and postintervention assessments of strength, endurance, and cognition. The primary outcomes were feasibility and adherence, defined as the ratio of scheduled and observed visits, and safety. We enrolled 131 participants, of whom 37 withdrew from the study. There were 17 (20%) withdrawals in the CARET+CTI and 20 (44%) in the control group. The observed-over-expected visit ratio was significantly higher in the intervention than in the control group (0.74±0.30 versus 0.54±0.38; P=0.003). A total of 99 adverse events were reported by 59 participants, none of which were serious and related to the intervention. Greater gains in physical, cognitive, and mood outcomes were found in the CARET+CTI group than in the control group, but were not statistically significant after adjustments. Conclusions A CARET+CTI intervention, after stroke, is safe, feasible, and has satisfactory participant adherence over 12 weeks. REGISTRATION URL: https://www.clini​caltr​ials.gov. Unique identifier: NCT02272426.

Abstract WP213: Association Between Thoracic Aorta Surgery and Long Term Risk of Stroke in Adults

Introduction: Thoracic aorta surgery carries a risk of perioperative stroke, but the long-term incidence of stroke after the perioperative period in these patients remains unclear. We therefore assessed the long-term risk of stroke in patients who underwent thoracic aorta repair.

Methods: We performed a retrospective cohort study using 2008-2015 claims data from a nationally representative 5% sample of Medicare beneficiaries. Our exposure of interest was thoracic aorta surgery, defined using ICD-9-CM hospital procedure codes for endovascular graft implantation (39.73) or surgical resection and replacement (38.45). Our primary outcome was ischemic stroke, defined using previously validated ICD-9-CM diagnosis codes. Patients with stroke during the index surgical hospitalization were excluded, since our focus was on long-term stroke risk after the perioperative period . Cox proportional hazards analysis was used to examine the association between thoracic aorta surgery and stroke risk after adjustment for demographics and vascular risk factors. Given a clear violation of the proportional hazards assumption, we calculated period-specific risk estimates.

Results: Among 1,751,719 beneficiaries (mean age 73 ±8 years), 1,402 underwent thoracic aorta repair. During 4.6 ±2.2 years of follow-up, 62,702 patients were diagnosed with ischemic stroke. The incidence of stroke was 1.24% (95% CI, 0.93-1.66%) per year after thoracic aorta repair compared to 0.77% (95% CI, 0.76-0.78%) per year in patients without thoracic aorta surgery. In adjusted models, there was an increased risk of stroke in the first 120 days after discharge from thoracic aorta surgery (HR, 2.1; 95% CI, 1.2-3.7), but no heightened risk was seen beyond 120 days after discharge from surgery (HR, 0.7; 95% CI, 0.5-1.0).

Conclusions: In a large sample of Medicare beneficiaries, thoracic aorta surgery was associated with an increased risk of ischemic stroke in the first 120 days after hospital discharge, but there was no excess risk beyond that time point.

Abstract WP419: Effect of Race-Ethnicity and Ct Angiography on Acute Kidney Injury During Blood Pressure Treatment for Intracerebral Hemorrhage

Background: Lowering blood pressure intensively in acute intracerebral hemorrhage (ICH) is associated with acute kidney injury (AKI). Blacks have a higher incidence of ICH as well as kidney disease. In addition, CT angiography (CTA), which may also be associated with AKI, is often done in acute ICH. Our objective was to investigate the relationship between aggressive BP management, CTA, race ethnicity and the risk of developing AKI in patients presenting with ICH.

Methods: Patients with spontaneous ICH hospitalized in 2017 and 2018 were included. Patients with underlying arteriovenous malformations, brain metastases, and aneurysms, were excluded. We calculated the difference between the highest and lowest systolic blood pressure (SBP) during the first 24 hours of admission. Creatinine levels at admission were compared to the highest creatinine during the first 7 days after admission. AKI was defined as absolute increase in creatinine of >0.3 or 50% increase from baseline creatinine. Linear regression models were used to assess the association between SBP difference, history of CTA and AKI.

Results: A total of 289 patients were included (mean±SD age 63±13), 40% were women, 41% Hispanics and 47% blacks. The majority of the patients underwent CTA (71%). The prevalence of AKI was high (30%). Blacks showed a significantly higher SBP compared to whites and Hispanics (p=.02), but no difference was found in AKI incidence (33% in Blacks vs. 27% in Caucasians and Hispanics (p=0.7). Higher BUN, creatinine and SBP on admission were associated with AKI (p=.001, p<.0001, and p=.0001, respectively). Those who developed AKI had a greater mean drop of SBP in 24 hours compared to those who did not (103mmHg vs. 84mmHg, p=.0007) and a higher prevalence of diabetes (p=.0013). In fully adjusted models, AKI was associated with SBP drop (p=.0003), but not with race/ethnicity (p=.6) or CTA (p=.06).

Conclusion: We confirm, in a real-life ICH population, the association between intense blood pressure lowering and development of AKI. Race/ ethnicity and CTA were not independently associated with AKI. Our findings do not suggest that obtaining a CTA in acute ICH poses significant additional risks on developing AKI.

Diastolic Blood Pressure Is Associated With Regional White Matter Lesion Load: The Northern Manhattan Study

Background and Purpose- Few studies have examined the separate contributions of systolic blood pressure and diastolic blood pressures (DBP) on subclinical cerebrovascular disease, especially using the 2017 American College of Cardiology/American Heart Association Blood Pressure Guidelines. Furthermore, associations with region-specific white matter hyperintensity volume (WMHV) are underexplored. Methods- Using data from the NOMAS (Northern Manhattan Study), a prospective cohort study of stroke risk and cognitive aging, we examined associations between systolic blood pressure and DBP, defined by the 2017 American College of Cardiology/American Heart Association guidelines, with regional WMHV. We used a linear mixed model approach to account for the correlated nature of regional brain measures. Results- The analytic sample (N=1205; mean age 64±8 years) consisted of 61% women and 66% Hispanics/Latinos. DBP levels were significantly related to WMHV differentially across regions (P for interaction<0.05). Relative to those with DBP 90+ mm Hg, participants with DBP <80 mm Hg had 13% lower WMHV in the frontal lobe (95% CI, -21% to -3%), 11% lower WMHV in the parietal lobe (95% CI, -19% to -1%), 22% lower WMHV in the anterior periventricular region (95% CI, -30% to -14%), and 16% lower WMHV in the posterior periventricular region (95% CI, -24% to -6%). Participants with DBP 80 to 89 mm Hg also exhibited about 12% (95% CI, -20% to -3%) lower WMHV in the anterior periventricular region and 9% (95% CI, -18% to -0.4%) lower WMHV in the posterior periventricular region, relative to participants with DBP 90≥ mm Hg. Post hoc pairwise t tests showed that estimates for periventricular WMHV were significantly different from estimates for temporal WMHV (Holms stepdown-adjusted P<0.05). Systolic blood pressure was not strongly related to regional WMHV. Conclusions- Lower DBP levels, defined by the 2017 American College of Cardiology/American Heart Association guidelines, were related to lower white matter lesion load, especially in the periventricular regions relative to the temporal region.

Measures of obesity are associated with MRI markers of brain aging: The Northern Manhattan Study

OBJECTIVE

To examine associations between measures of obesity in middle to early-old age with later-life MRI markers of brain aging.

METHODS

We analyzed data from the Northern Manhattan MRI Sub-Study (n = 1,289). Our exposures of interest were body mass index (BMI), waist circumference (WC), waist-to-hip ratio, and plasma adiponectin levels. Our outcomes of interest were total cerebral volume (TCV), cortical thickness, white matter hyperintensity volume (WMHV), and subclinical brain infarcts (SBI). Using multivariable linear and logistic regression models adjusted for sociodemographics, health behaviors, and vascular risk factors, we estimated β coefficients (or odds ratios) and 95% confidence intervals (CIs) and tested interactions with age, sex, and race/ethnicity.

RESULTS

On average at baseline, participants were aged 64 years and had 10 years of education; 60% were women and 66% were Caribbean Hispanic. The mean (SD) time lag between baseline and MRI was 6 (3) years. Greater BMI and WC were significantly associated with thinner cortices (BMI β [95% CI] -0.089 [-0.153, -0.025], WC β [95% CI] -0.103 [-0.169, -0.037]) in fully adjusted models. Similarly, compared to those with BMI <25, obese participants (BMI ≥30) exhibited smaller cortical thickness (β [95% CI] -0.207 [-0.374, -0.041]). These associations were particularly evident for those aged <65 years. Similar but weaker associations were observed for TCV. Most associations with WMHV and SBI did not reach statistical significance.

CONCLUSIONS

Adiposity in early-old age is related to reduced global gray matter later in life in this diverse sample. Future studies are warranted to elucidate causal relationships and explore region-specific associations.

Topography of Vertebral Artery Origin Plaques: Characteristics and Determinants

BACKGROUND

Atherosclerotic plaques located at the vertebral artery ostium (VAo) are a mechanism for posterior circulation stroke, but little is known about VAo plaque topography and formation. In this study, we describe the topography of atherosclerotic plaques involving the origin of the vertebral artery (VA).

METHODS

Cross-sectional analyses of extracranial duplex studies were performed, and VAo plaques were classified based on their topography in 3 groups: (1) exclusively at the VA ostium; (2) predominantly subclavian, with extension into the vertebral ostium; and (3) predominantly ostial, with extension into the subclavian artery). Chi-square and analysis of variance tests were performed to investigate the association between VAo plaque topography and continuous and categorical variables, respectively.

RESULTS

A total of 99 of 481 (21%) ultrasound duplex studies showed VAo plaques. The majority of the plaques (60%) were found to extend from the subclavian to the ostium. Plaques occurred more frequently at the medial wall of the VAo. No vascular risk factors were associated with plaque formation; however, women were more likely to have plaques involving predominantly or exclusively the VAo (P = .004).

CONCLUSIONS

We describe 3 different patterns of VAo involvement in patients with ostial atherosclerotic VA disease. VAo plaques occurred almost exclusively at the medial wall of the vessel. Women had more plaques involving predominantly the origin. Prospective studies are needed to investigate the clinical significance of these findings.

Abstract WP142: Baseline and Demographic Factors Associated With Improvements in Physical Activity, Cognition and Mood: Preliminary Data from the Bugher Foundation’s Stroke and Exercise Study

Background: The Bugher Stroke and Exercise Study examines the impact of a structured exercise and cognitive training program after stroke. In this preliminary analysis we investigated baseline predictors and demographics related to physical, cognitive and affective improvements.

Methods: Participants with recent stroke and limited physical activity ≥ 3 months prior to enrollment were randomized to one of two arms of a 3-month intervention. Arm 1 (N=62) received exercise (strength & cardiovascular) and cognitive training. Arm 2 (N=35) received light stretching and sham cognitive training. Outcome measures included depression (CES-D), cognition (MoCA), stroke impact scale (SIS), impairment (NIHSS), degree of disability (mRS), and physical measures of hand grip (HG), time up and go (TUG), 30-second chair stand test, 6-minute walk, waist circumference, BMI and blood pressure (BP). The trial is ongoing, therefore treatment group comparisons were not available. T-tests evaluated change in outcome measures among all participants. Regression analyses evaluated demographic variables and baseline factors (i.e., time-since-stroke, ischemic vs. hemorrhagic, & pre-stroke physical activity) associated with change in outcome measures.

Results: To date, 97 participants were enrolled ( M age 59±11 years; 34% women; 53% white, 49% Hispanic, 39% black & 7% other). Participants demonstrated significant improvement on the CES-D (p=.005), MoCA (p=.005), NIHSS (p<.001), SIS (p=.015), mRS (p<.001), HG (p=.002), TUG (p=.004), 30-second chair (p<.001), 6-minute walk (p=.001), waist circumference (p=.010), and both systolic (p=.009) and diastolic (p<.001) BP. Regression analyses revealed that older adults were less likely to improve in MoCA scores (p=.010), 6-minute walk (p=.041), and systolic BP (p=.032). Participants with more pre-stroke physical activity demonstrated greater improvement in 6-minute walk (p=.024). Black participants saw less decline in systolic BP (p=.033) while participants with hemorrhagic (vs. ischemic) stroke saw less decline in diastolic BP (p=.039).

Conclusions: Participation in an exercise and cognitive training intervention benefit stroke survivors; however, improvement may depend on baseline and demographic factors.

Abstract WP423: Adiponectin and Components of Metabolic Syndrome are Associated With Cortical Thickness: The Northern Manhattan Study

Objective: Examine the association of adiponectin and metabolic syndrome components with measures of global and lobar cortical thickness.

Background: Metabolic syndrome has been associated with structural brain changes, but the relationship of adiponectin and cortical thickness is understudied.

Methods: The Northern Manhattan Study MRI Sub-Study is a mostly Hispanic, stroke-free, prospective cohort study of older adults. Cortical thickness (mm) was obtained from T1-weighted brain MRIs using the publically-available Freesurfer software. Regional cortical thickness metrics were averaged to obtain mean lobar cortical thickness. Adiponectin (μg/mL) was measured at baseline (1993-2001). Metabolic syndrome components were measured at MRI Sub-Study baseline (2003-2008). We estimated the cross-sectional associations of adiponectin (per 1 SD) and metabolic syndrome components with global and lobar cortical thickness (per 1 SD) using multivariable linear regression models adjusted for sociodemographic factors, APOE ε4 allele presence, and health-related behaviors. All hypothesis testing was two-sided with an alpha level of 5%.

Results: Freesurfer data were available in 947 participants (mean±SD age=70±9 years, 63% women, 66% Hispanics, 16% black, and 15% white). Global cortical thickness was normally distributed (mean±SD = 2.3±0.1mm). In fully adjusted models, 1 SD (4.9μg/mL) increase in adiponectin was associated with smaller overall (β [95%CI] = -0.07 [-0.14, -0.0002]) and parietal cortical thickness (β [95%CI] = -0.08 [-0.03, -0.0002]). Greater blood glucose levels significantly associated with smaller occipital cortical thickness (β [95%CI] = -0.003 [-0.006, -0.0007]). Greater waist circumference was significantly associated with smaller frontal cortical thickness (β [95%CI] = -0.02 [-0.04, -0.0007]). Neither blood pressure (systolic and diastolic) nor cholesterol (total, HDL-C, and LDL-C) were associated with global or regional cortical thickness.

Conclusions: There was heterogeneity in the cross-sectional associations between adiponectin, metabolic syndrome components, and regional cortical thickness. Further studies are needed to explore the temporal relationship between risk factors and cortical thinning.

Abstract TP385: A Mobile-Friendly Website to Reduce Stroke Caregiver Burden: A Qualitative and Pilot Study

Background: Researchers estimate the prevalence of stroke caregiver burden to be 25-50%. Currently, there are no feasible, user-centered interventions in practice to improve stroke caregiver burden.

Objectives: To refine the Stroke Caregiver Support System, a mobile-friendly website, with feedback from structured interviews, and to test the feasibility of the Stroke Caregiver Support System with a small pilot study.

Methods: We employed a user-centered design framework for the development of our intervention, which includes 9 topical modules with brief introductory videos and curated resources from publically available sources. To refine the intervention, we used feedback from structured qualitative interviews with stroke caregivers for each aspect of the intervention. We then enrolled 8 stroke caregivers in a pilot study to measure baseline caregiver burden and depressive symptoms and test the feasibility of the intervention. All descriptive statistics were computed using SAS 9.4.

Results: In structured qualitative interviews (N=4), stroke caregivers were aged 53-59 years; 3 of these caregivers were daughters of stroke survivors, and 2 identified as Hispanic/Latino. The main criticisms of the website included: a) low volume on videos, b) the need for more specific information for the physical challenges of caregiving, and c) the need to improve the language to make it less “scientific.” Generally, caregivers found the modules relevant and the content useful. The pilot study included 8 caregivers (mean [SD] age = 45 [17]), including 7 females, 5 who identified as Hispanic/Latino, and 6 who had a college education or greater. These caregivers had a mean (SD) Zarit burden score of 17 (8) and mean (SD) 10-item CES-D score of 14 (5). In general, caregivers found the website content and organization helpful, but the design and layout needed improvement. Caregivers emphasized that each “caregiver journey” was different, so tailored intervention is needed.

Conclusions: Caregivers provided important feedback for the design of this mobile-friendly, educational intervention. Post-intervention measures will give insight into the feasibility and potential efficacy of the Stroke Caregiver Support System to attenuate caregiver burden.

Abstract P119: Hypertension Trends in Florida Stroke Patients. The Florida Puerto Rico Collaboration to Reduce Stroke Disparities

Aim: To describe hypertension prevalence (HTN) in a race diverse stroke registry and investigate associated presentation in patients admitted for acute ischemic stroke (AIS) and hemorrhagic stroke in Florida hospitals participating in the Florida Collaboration to Reduce Stroke Disparities (CReSD).

Background: HTN affects about 30% of U.S. adults and this prevalence doubles among stroke survivors. HTN is a major risk factor for incident stoke and recurrent stroke. Quantifying the prevalence of HTN in stroke survivors is important to guide secondary stroke prevention.

Methods: 121,333 stroke cases were analyzed from 69 FL hospitals participating in the AHA Get With the Guidelines-Stroke Program and FL CReSD Stroke Registry. Hypertension was defined as systolic blood pressure >140mmHg. Demographics and CV risk factors were collected at admission. We investigated the differences in HTN prevalence between race groups: white (65%), black (20%) and Hispanic (15%) as well as between age groups: 18-60, 61-80 and >80 years old. Temporal trends of HTN prevalence were also analyzed from 2010 to 2016.

Results: In our stroke population, mean age was 70±15 and 60,667 were women (50%). HTN prevalence was 65% (78,553/121,333). Patients with HTN were significantly older (mean age 72±14 vs. 67±16 in non-HTN patients) and presented significantly higher prevalence of other CV risk factors such as diabetes, hyperlipidemia and had more previous stroke/TIAs. Women had greater prevalence of HTN (66% vs. 64% in males) in all age groups. Greater HTN prevalence was in blacks (70%) compared to white (64%) and Hispanics (58%) in all age groups. Interestingly, a significantly higher prevalence of HTN was found in AIS compared to hemorrhagic stroke but a higher SBP was observed in hemorrhagic strokes compared to AIS. Prevalence of HTN decreased of 8% from 2010 to 2016. Largest decline was observed among women (9%) and blacks (13%).

Conclusions: In our large Stroke Registry we observed higher prevalence of HTN in women, blacks and AIS. We also observe a decreasing trend over the past 7 years, especially among women and minorities (blacks and Hispanics). These findings provide an opportunity to design and implement interventions to reduce disparities in HTN and improve stroke outcome.

Serotonin and noradrenaline reuptake inhibitors improve micturition control in mice

Poor micturition control may cause profound distress, because proper voiding is mandatory for an active social life. Micturition results from the subtle interplay of central and peripheral components. It involves the coordination of autonomic and neuromuscular activity at the brainstem level, under the executive control of the prefrontal cortex. We tested the hypothesis that administration of molecules acting as reuptake inhibitors of serotonin, noradrenaline or both may exert a strong effect on the control of urine release, in a mouse model of overactive bladder. Mice were injected with cyclophosphamide (40 mg/kg), to increase micturition acts. Mice were then given one of four molecules: the serotonin reuptake inhibitor imipramine, its metabolite desipramine that acts on noradrenaline reuptake, the serotonin and noradrenaline reuptake inhibitor duloxetine or its active metabolite 4-hydroxy-duloxetine. Cyclophosphamide increased urine release without inducing overt toxicity or inflammation, except for increase in urothelium thickness. All the antidepressants were able to decrease the cyclophosphamide effects, as apparent from longer latency to the first micturition act, decreased number of urine spots and volume of released urine. These results suggest that serotonin and noradrenaline reuptake inhibitors exert a strong and effective modulatory effect on the control of urine release and prompt to additional studies on their central effects on brain areas involved in the social and behavioral control of micturition.