Population-based Stroke Study Research Articles

Abstract TP1: Changing Trends in the Epidemiology of Subarachnoid Hemorrhage: A Population-Based Study

Background: There are conflicting data on temporal trends in subarachnoid hemorrhage (SAH) incidence and outcomes. We examined trends from 1993-2020 in a long-running population-based stroke study conducted in the Greater Cincinnati Northern Kentucky (GCNK) region. Methods: Using a well-validated approach, we ascertained all incident nontraumatic SAHs among residents of the GCNK region in the following study periods; July 1993-June 94, calendar years 1999, 2005, 2010, 2015, and 2020. Potential cases were identified by ICD codes, abstracted, and then adjudicated by physicians. Aneurysmal SAH (aSAH) was defined as those with culprit aneurysms; cases with no available vessel imaging were considered aSAH if the hemorrhage volume was “massive” or if the patient died rapidly after onset. Incidence rates were compared over time using linear regression after normalizing to 2010 census demographics. The primary outcome assessed was unadjusted 30-day Case Fatality Rate (CFR), which was available through 2015. Results: We identified 518 SAH cases, of which 372 were aSAH (71.8%). Overall SAH incidence rate was stable over time, ranging from 8-10 cases per 100,000 person-years (Figure Panel A); however, the rate of aSAH showed a statistically significant decline, going from 7.2 cases/100,000 person-years in 1993 to 5.2 cases/100,000 person-years in 2020 (trend P =0.02). There was a nonsignificant increase in nonaneurysmal SAH ( P =0.09 for trend). Overall 30-day CFR declined significantly through 2015 ( P =0.006, Figure Panel B), driven predominantly by a decline in aSAH CFR (from 39.3% to 23.7%, trend P =0.04). Conclusion: We observed a significant decline in the incidence of aSAH from 1993-2020; however, overall SAH incidence was stable in the setting of numerically more nonaneurysmal SAHs. Further study is needed to understand the causes of this trend. 30-Day CFR has significantly improved both for overall SAH and for aSAH.

Mexican Americans agree to participate in longitudinal clinical research more than non-Hispanic whites

BackgroundThe National Institutes of Health has advocated for improved minority participation in clinical research, including clinical trials and observational epidemiologic studies since 1993. An understanding of Mexican Americans (MAs) participation in clinical research is important for tailoring recruitment strategies and enrollment techniques for MAs. However, contemporary data on MA participation in observational clinical stroke studies are rare. We examined differences between Mexican Americans (MAs) and non-Hispanic whites (NHWs) participation in a population-based stroke study.MethodsWe included 3,594 first ever stroke patients (57.7% MAs, 48.7% women, median [IQR] age 68 [58–79]) from the Brain Attack Surveillance in Corpus Christi Project, 2009–2020 in Texas, USA, who were approached and invited to participate in a structured baseline interview. We defined participation as completing a baseline interview by patient or proxy. We used log-binomial models adjusting for prespecified potential confounders to estimate prevalence ratios (PR) of participation comparing MAs with NHWs. We tested interactions of ethnicity with age or sex to examine potential effect modification in the ethnic differences in participation. We also included an interaction between year and ethnicity to examine ethnic-specific temporal trends in participation.ResultsBaseline participation was 77.0% in MAs and 64.2% in NHWs (Prevalence Ratio [PR] 1.20; 95% CI, 1.14–1.25). The ethnic difference remained after multivariable adjustment (1.17; 1.12–1.23), with no evidence of significant effect modification by age or sex (Pinteraction by age = 0.68, Pinteraction by sex = 0.83). Participation increased over time for both ethnic groups (Ptrend < 0.0001), but the differences in participation between MAs and NHWs remained significantly different throughout the 11-year time period.ConclusionMAs were persistently more likely to participate in a population-based stroke study in a predominantly MA community despite limited outreach efforts towards MAs during study enrollment. This finding holds hope for future research studies to be inclusive of the MA population.

Abstract WP43: Characteristics And Management Of Hospitalized Retinal Artery Occlusion Patients In The Era Of Updated Guidelines: A Population-based Study

Background: Retinal artery occlusion (RAO) is a stroke equivalent that causes significant morbidity. There has been growing emphasis on urgent in-hospital evaluation of these patients, both to facilitate potential thrombolytic therapy and expedite workup; however, little is known regarding its effect on systems of care. We thus examined presenting characteristics and management of hospitalized RAO patients using the Greater Cincinnati Northern Kentucky Stroke Study (GCNKSS). Methods: The GCNKSS is a population-based study of stroke in a 5-county region with a population of 1.3 million representative of the USA in terms of Black race, income, and education. All cases of RAO among Black individuals from July 2019-December 2020 and among White individuals from 2020 were chart abstracted using ICD codes. All cases underwent physician adjudication. Demographic and clinical data were recorded. Results: We identified 57 hospitalizations with acute RAO among 55 patients. Characteristics of their hospitalization and demographics are shown (Table). Notably, 19% (11/57) of patients presented in a thrombolytic window of ≤3.5 and average time from symptom onset to evaluation was 17 hours. Most patients initially interacted with a subspecialist (53%) and presented to the ED in delayed fashion. One patient received thrombolytic therapy, four (7%) patients underwent carotid revascularization, and no patients had newly identified atrial fibrillation, cardiac thrombus, or endocarditis. Discussion: Our population-based study found only a minority of patients presented within a thrombolytic window, suggesting that systems of care need to promote more rapid evaluation of these patients. Very few patients received select intervention, but the high impact of carotid revascularization may warrant urgent evaluation of even low risk patients. Further study of long-term outcomes in this patient population is called for.

Abstract 82: Sex Differences In Recurrent Stroke: Twenty-Year Trends From A Population-Based Study

The growing number of stroke survivors in the US, especially among women, makes understanding sex-specific trends in recurrent strokes crucial. Yet, such data are rare. We estimated 20-year sex-specific trends in recurrence in a population-based stroke study. Methods: We included first-ever ischemic strokes (IS) ascertained between January 1, 2000 and December 31, 2019 from the Brain Attack Surveillance in Corpus Christi (BASIC) Project in South Texas. Time to recurrence was calculated from first-ever IS to recurrence, death, or December 31, 2019, whichever came first. We estimated the cumulative incidence function (CIF) of recurrence by a multivariable Fine-Gray subdistribution hazard model, which accounted for the competing risk of death. An interaction term between calendar year and sex was used to generate 1-year and 5-year sex-specific trends in risks of recurrence between 2000-2019 from the fitted CIF. Results: Among the 5,752 IS (median age 69, 49.9% women), 786 (13.7%) had recurrences over a median of 7.6 years of follow-up and 2,653 (46.1%) died over a median of 3.7 years of follow-up. Women had significantly higher adjusted 1-year and 5-year risks of recurrence than men in 2000 (Figure). One-year and 5-year risk of recurrence declined in both sexes over time but women experienced larger declines such that the risks were similar between both sexes around 2009 but higher among men after that. The largest sex difference in recurrence was in the 5-year risk in 2000 with women having 5.0% (1.5%-8.4%) higher risk. Conclusions: The welcoming trends in recurrent strokes suggest successful secondary stroke prevention, especially in women, where greater declines were noted.

Abstract TMP106: Decline In The Severity Of Hospitalized Ischemic Stroke 2005-2015: The Greater Cincinnati/Northern Kentucky Stroke Study

Background: Monitoring changes in ischemic stroke severity at the population level is important as changes in risk factors and clinical treatments could influence stroke severity. We describe trends in the distribution of NIHSS across 3 time periods in a population-based epidemiologic stroke study. Methods: In 2005, 2010, and 2015 all adult acute ischemic strokes occurring within the Greater Cincinnati area presenting to 15 hospitals were ascertained using discharge codes (ICD-9 433-436; IDC-10 I63-I68, G45-46). Following physician verification, confirmed ischemic stroke cases underwent chart abstraction including estimation of a retrospective (rNIHSS) score at presentation. Descriptive statistics (rNIHSS median, IQR) were generated by survey year, demographics, and medical history. Using a binary definition of stroke severity (median rNIHSS score &amp;gt 4 versus &amp;lt 4), multivariable logistic regression was used to estimate changes in stroke severity over time, adjusting for potential confounders. Random effects were used to account for multiple admissions occurring in the same subject. Results: The number of ischemic stroke admissions in the 2005, 2010, and 2015 surveys was 1778, 1903, and 1933, respectively (Table). The median (IQR) rNIHSS scores were 3 (2-7), 3 (1-6), and 2 (1-6) across the 3 surveys, respectively; the proportion of admissions with rNIHSS &amp;gt 4 was 48%, 39% and 37%, respectively. After adjusting for demographics, medical history and pre-stroke function, compared to 2005, the odds ratio for more severe stroke was 0.69 (95% CI= 0.60-0.79, p=0.001) in 2010 and 0.63 (95% CI= 0.55-0.73, p=0.001) in 2015. Conclusions: In this population- based study there was a statistically significant change in the severity of ischemic stroke hospitalizations with increases in the proportion of milder strokes over time. Potential reasons for this change need to be explored but could include changes in risk factors, clinical treatments or diagnostic approach.

Abstract 68: Socioeconomic Factors Associated With Ems-documented Stroke Chief Complaints In The Greater Cincinnati Northern Kentucky Stroke Study (GCNKSS)

Background: Accurate identification of stroke by EMS is necessary for triage and pre-notification within stroke systems of care. Our objective was to describe disparities in the documentation of stroke as the patient’s chief complaint (CC) by EMS in a large population-based stroke study. Methods: We included physician-adjudicated strokes and TIAs occurring among adults ≥18 years old in 2015 in the GCNKSS study population, based in a 5-county area of Southern Ohio/Northern Kentucky. Strokes in which EMS was not used and events occurring in the hospital, during EMS transport, at an unknown location, or outside the study region were excluded. The documented CC by EMS (stroke/CVA, MI, seizure, fall, weakness/numbness, headache, or other) were compared between race/sex subgroups. Sequential multivariable logistic regression was performed to identify associations between race, sex, and social determinants of health with an EMS-documented stroke CC. Social determinants included living arrangement and census tract social deprivation index (SDI). Results: A total of 1451 stroke/TIA events were included. White women had the highest proportion of EMS-documented stroke CCs (56%), more than Black women (48%), White men (45%), and Black men (42%), (p=0.02). Black race was inversely associated with an EMS-documented stroke CC in initial models but was collinear with SDI and no longer significant when SDI was included. In the full model, age, previous stroke, and living with others were associated with an EMS-documented stroke CC, while SDI and CAD were inversely associated with EMS-documented stroke CCs. (Table) Conclusion: Patients living in census tracts characterized by social deprivation were less likely to have EMS-documented stroke CCs, suggesting differences in either patient or EMS recognition of stroke. Further work is needed to explore potential confounders including EMS protocols and to improve identification of stroke by patients and EMS providers.

Incidence and Outcomes of Acute Cerebrovascular Events: Methodology of the Population-Based Normandy Stroke Study

Background: The number of strokes has been steadily increasing due to the aging of the population, and its management has changed dramatically in recent years. Nevertheless, there are few unbiased epidemiological studies to investigate the incidence of strokes and their long-term prognosis. Methods: The Normandy Stroke Study (NSS) is a prospective population-based study of all strokes and transient ischemic attacks in a large urban, suburban, and rural area in the Northwest of France. It was designed to meet the current gold standard in stroke epidemiological study by using multiple overlapping sources for case identification. It also aimed to assess the impact of socioeconomic disparities and long-term prognosis of stroke through an additional follow-up up to 3 years after the event to better understand the functional and cognitive prognostic of stroke as well as the quality of life in patients after stroke. Conclusion: NSS will provide important data on the epidemiology and long-term consequences of stroke at the population level and will help care providers adapt resource allocation.

Differences in Multiple Risk Factors Between Black and White Individuals With Young-Onset Ischemic Stroke.

Stroke in young adults constitutes 15%-18% of all ischemic stroke cases. Black individuals have an excess risk of ischemic stroke especially in young adults. Although it is known that Black patients have a higher prevalence of hypertension and diabetes, few studies have addressed the association of concurrent multiple vascular risk factors with the excess risk of early-onset stroke among Black individuals. A population-based case-control study of early-onset ischemic stroke, ages 15-49 years, was conducted in the Baltimore-Washington DC region between 1992 and 2007. Presence of the risk factors of obesity, hypertension, diabetes, and current smoking were obtained from both cases and controls by an in-person interview. Risk factor groups were defined as (1) 1 risk factor, (2) 2 risk factors, (3) 3 risk factors, and (4) 4 risk factors. Logistic regression analysis adjusting for age and sex was used to evaluate the association between each risk factor group and ischemic stroke compared with the reference group with no risk factors. The study included 1,034 cases and 1,091 controls. Of the cases, 47% were Black, 54% were men, and the mean (±SD) age was 41.0 (±6.9) years. The odds of having a stroke increased exponentially as the number of risk factors increased, 2.1, 2.6, 7.6, 16.5, all p < 0.001, for groups 1-4, respectively. When stratified by race, Black individuals were approximately 6 times more likely to have all 4 risk factors. The risk of stroke in young adults increased exponentially with the number of risk factors. Young Black patients with ischemic stroke were approximately 6 times more likely to have the co-occurrence of obesity, hypertension, diabetes, and smoking compared with their White counterparts. Targeting public health interventions to identify and improve care to Black young adults with multiple stroke risk factors may have substantial impact on lowering risk of stroke.

Abstract TMP102: Timing Of Withdrawal Of Antithrombotics And Impact On Stroke

Background: Antithrombotic medications (AT) are often withheld before procedures to reduce risk of bleeding. In 2005, members of our team reported that 5.2% of ischemic strokes were associated with the withdrawal of AT in the preceding 60 days. Subsequently, new medications, including DOACs, have become widely used. Given changing prescription and practice patterns we sought to compare rates of stroke in the setting of antithrombotic withdrawal in 2010 and 2015. Methods: The GCNKSS is a population-based stroke study from the Greater Cincinnati region. In 2005, 2010, and 2015, we captured all strokes in the Greater Cincinnati/Northern Kentucky 5 county area by screening ICD9 codes 430-436 and ICD10 (2015) codes I60-I68, and G45-46. Study nurses abstracted all cases and physicians adjudicated each event. Data regarding the withdrawal of AT and timing were captured. 2005 data was included as a reference. Fisher’s exact test was used to examine differences by years. Results: In 2010 and 2015, 4768 cases of ischemic stroke were identified. Across the study periods, those that were on AT at time of stroke versus those who stopped AT &lt;60 days prior to incident stroke were of similar median age, 73 and 74 years respectively, and of similar sex (55 vs 52%) and race (21 vs 18%) distribution. Atrial fibrillation (30 vs 52%) and median baseline NIHSS (3 vs 4) were higher in those who stopped AT &lt; 60 days prior to stroke than those on AT. Of the 4768, 228 (4.8%) occurred within 60 days of withdrawal of an antithrombotic medication. The proportion of strokes in the setting of warfarin being held is the only AT that had a significant change, decreasing in 2015 (Table). Conclusions: The withdrawal of AT is associated with 228 (4.8%) of ischemic strokes within 60 days in our study population. These rates remain consistent across our study periods. This highlights that despite new agents, stroke in the setting of AT withdrawal remains consistent and the decision to stop AT must be carefully considered.

Abstract WP192: Ischemic Stroke Mechanisms By Sex And Race Over Time In The Greater Cincinnati Northern Kentucky Stroke Study

Background: Identifying the mechanism of acute ischemic stroke (AIS) is critical to determining secondary stroke prevention strategies. As past data conflict on sex and race differences in stroke mechanism, we aimed to describe stroke mechanisms by sex and race over time in a population-based study of AIS cases with a focus on strokes with unknown mechanism. Methods: We included physician adjudicated, hospital ascertained incident AIS among adults over five study periods (1993/4, 1999, 2005, 2010, 2015) from the Greater Cincinnati Northern Kentucky Stroke Study. Stroke mechanisms were adjudicated by trained study physicians and included: small vessel disease, cardioembolic, large artery disease, other, and unknown. The percentage of AIS cases in each of the 5 categories was reported by sex and race in each of our five 1-year study periods, and trends over time by subgroup were tested using the Cochran-Armitage trend test. Results: We included 8349 AIS over 5 study periods: 4693 (56%) were women, 1607 (19%) were Black, mean age was 70.5 (14.3). Over the 22-year time period, the proportion of strokes whose mechanism was ‘unknown’ decreased in women (46.1%, 1993/4 to 38.5%, 2015 , p&lt;0.0001), men (46.2%, 1993/4 to 33.9%, 2015, p&lt;0.0001), Black (51.8%, 1993/4 to 40.7%, 2015, p=0.004), and White (45.0%, 1993/4 to 40.7%, 2015, p&lt;0.0001) patients. The proportion of small vessel strokes increased over time in men, strokes of ‘other’ mechanisms increased in all subgroups, and cardioembolic strokes increased in women and White individuals only (Figure). Conclusions: In a large population-based stroke study, the proportion of AIS with an unknown mechanism has decreased over time in all demographic groups, while trends in those categorized as cardioembolic or small vessel disease varied by sex and/or race. As changes in imaging utilization may be a contributor to our findings, future work investigating possible sex and race differences in diagnostic evaluations of AIS is warranted.

Associations of Chronic Kidney Disease With Dementia Before and After TIA and Stroke: Population-Based Cohort Study.

Background and ObjectivesIndividuals with chronic kidney disease (CKD) appear to be at increased risk of cognitive impairment, with both vascular and neurodegenerative mechanisms postulated. To explore the vascular hypothesis, we studied the association between CKD and dementia before and after TIA and stroke.MethodsIn a prospective, population-based cohort study of TIA and stroke (Oxford Vascular Study; 2002–2012), pre-event and new postevent dementia were ascertained through direct patient assessment and follow-up for 5 years, supplemented by review of hospital/primary care records. Associations between pre-event dementia and CKD (defined as an estimated glomerular filtration rate [eGFR] <60 mL/min/1.73 m2) were examined using logistic regression and between postevent dementia and CKD using Cox and competing risk regression models, adjusted for age, sex, education, stroke severity, prior stroke, white matter disease, diabetes mellitus, and dysphasia.ResultsAmong 2,305 patients with TIA/stroke (median [interquartile range] age, 77 [67–84] years, 1,133 [49%] male, 688 [30%] TIA), 1,174 (50.9%) had CKD. CKD was associated with both pre-event (odds ratio [OR] 2.04 [95% confidence interval (CI) 1.52–2.72]; p < 0.001) and postevent dementia (hazard ratio [HR] 2.01 [95% CI 1.65–2.44]; p < 0.001), but these associations attenuated after adjustment for covariates (OR 0.92 [0.65–1.31]; p = 0.65 and HR 1.09 [0.85–1.39]; p = 0.50). The results were similar when a competing risk model was used (subdistribution HR [SHR] 1.74 [1.43–2.12]; p < 0.001, attenuating to 1.01 [0.78–1.33]; p = 0.92 with adjustment). CKD was more strongly associated with late (>1 year) postevent dementia (SHR 2.32 [1.70–3.17]; p < 0.001), particularly after TIA and minor stroke (SHR 3.08 [2.05–4.64]; p < 0.001), but not significantly so after adjustment (SHR 1.53 [0.90–2.60]; p = 0.12).DiscussionIn patients with TIA and stroke, CKD was not independently associated with either pre- or postevent dementia, suggesting that renal-specific mechanisms are unlikely to play an important role in aetiology.

Black-White Differences in Ischemic Stroke Risk Factor Burden in Young Adults.

Although the US Black population has a higher incidence of stroke compared with the US White population, few studies have addressed Black-White differences in the contribution of vascular risk factors to the population burden of ischemic stroke in young adults. A population-based case-control study of early-onset ischemic stroke, ages 15 to 49 years, was conducted in the Baltimore-Washington DC region between 1992 and 2007. Risk factor data was obtained by in-person interview in both cases and controls. The prevalence, odds ratio, and population-attributable risk percent (PAR%) of smoking, diabetes, and hypertension was determined among Black patients and White patients, stratified by sex. The study included 1044 cases and 1099 controls. Of the cases, 47% were Black patients, 54% were men, and the mean (±SD) age was 41.0 (±6.8) years. For smoking, the population-attributable risk percent were White men 19.7%, White women 32.5%, Black men 10.1%, and Black women 23.8%. For diabetes, the population-attributable risk percent were White men 10.5%, White women 7.4%, Black men 17.2%, and Black women 13.4%. For hypertension, the population-attributable risk percent were White men 17.2%, White women 19.3%, Black men 45.8%, and Black women 26.4%. Modifiable vascular risk factors account for a large proportion of ischemic stroke in young adults. Cigarette smoking was the strongest contributor to stroke among White patients while hypertension was the strongest contributor to stroke among Black patients. These results support early primary prevention efforts focused on smoking cessation and hypertension detection and treatment.

A prospective population-based study of stroke in the Central Region of Iran: The Qom Incidence of Stroke Study.

Based on the few population-based studies that have been conducted in the Middle East, we determined the incidence of stroke in Qom, one of the central provinces of Iran. The Qom province includes an estimated at-risk population of about 1 million. During a 12-month period (November 2018-November 2019), all first-ever strokes occurring in the target population were registered. Hospitalized cases were ascertained by discharge codes. Out-of-hospital cases were ascertained by a prospective screening of emergency medical services, emergency departments, ambulances records, primary care clinics, rural and urban public health centers, primary care physician offices, and neurologists' offices. Crude and age-adjusted incidence rates (per 100,000 person-years) were calculated. During the study period, 1462 first-ever strokes occurred with a mean age of 68.1 (17-103) years; of these 45.2% were females (661 cases). The crude annual incidence rate per 100,000 at-risk populations was 145.4 (95% confidence interval, 138.1-153.0) for all types of stroke (156.5 for males and 134.3 for females), 26.4 (95% confidence interval, 23.5-29.8) for hemorrhagic stroke, and 114 (95% confidence interval, 105-121) for ischemic stroke. The incidence rate adjusted to the world population was 201.4 (95% confidence interval, 193-210) per 100,000 at-risk populations (adj incidence, 218.5 for males vs 187.4 for females). The total fatality rate during the first 28 days was 19.6%. This study states that in this region there is a high incidence of stroke, which occurs at a younger age than the global average. There was a high prevalence of underlying stroke risk factors.

The Association between Substance Use Disorders and Long-Term Outcome of Stroke: Results from a Population-Based Study of Stroke among 450,229 Urban Citizens

Introduction: Little is known regarding long-term stroke outcomes in patients with substance use disorder (SUD). Based on anecdotal data, some individuals use illicit drugs, particularly opioids, in an attempt to reduce stroke mortality, disability, or recurrence. This study is aimed to assess the effect of SUD on stroke outcomes. Methods: Patients were recruited from the Mashhad Stroke Incidence Study, a population-based study of stroke in Iran. For a period of 1 year, all patients with first-ever stroke (FES) were recruited and then followed up for the next 5 years. Disability and functional dependency were defined using modified Rankin Scale (>2) and Barthel Index (<60), respectively. We compared the cumulative rates of mortality in follow-up points using the log-rank test. We used multivariable logistic, Cox regression and competing risk models to assess adjusted hazard ratio (aHR) with 95% confidence interval (CI) of stroke disability, functional dependency, mortality, and recurrence among those with a history of SUD. Results: 595 FES patients (mean age of 64.6 ± 14.8 years) were recruited in this study. Eighty-one (13.6%) were current substance users, including opium (n = 68), naswar (n = 5, 6.1%), hashish (n = 1), heroin (n = 1), and (n = 7) others. The frequency of vascular risk factors was similar between the SUD and non-SUD groups, except for a higher rate of cigarette smoking in the SUD group (p < 0.001). After adjusting for various sociodemographic variables, vascular risk factors, and the severity of stroke at admission, SUD increased the 3-month (aHR: 1.60, CI: 1.01–2.49), 1-year (aHR: 1.73, CI: 1.20–2.65), and 5-year (aHR: 1.72, CI: 1.23–2.35) poststroke mortality risk. We did not observe a significant change in the risk of stroke recurrence, disability, and functional dependency in those with a history of SUD. Conclusion: SUD increased the hazard ratio of stroke mortality with no effect on the disability rate. The public should be advised about the potential harm of substance abuse.

Incidence, risk factors, prognosis, and health-related quality of life after stroke in a low-resource community in Chile (ÑANDU): a prospective population-based study

Stroke is a leading cause of disability and death worldwide. The best estimates of local, national, and global burden of stroke are derived from prospective population-based studies. We aimed to investigate the incidence, risk factors, long-term prognosis, care, and quality of life after stroke in the Ñuble region of Chile. We did a prospective community-based study with use of multiple overlapping sources of hospitalised, ambulatory, and deceased cases. Standardised diagnostic criteria were used to identify and follow up all cases occurring in the resident population of the Ñuble region, Chile (in a low-income rural-urban population including predominantly people of Indigenous-European heritage), for 1 year. Participants were included if they had a clinical diagnosis of stroke confirmed according to the study criteria. All cases were adjudicated by vascular neurologists. Incidence rates of first-ever stroke were calculated from the population of Ñuble according to the 2017 national census. From April 1, 2015, to March 31, 2016, we ascertained 1103 stroke cases, of which 890 (80·7%) were first-ever incident cases. The mean age of patients with first-ever stroke was 70·3 years (SD 14·1) and 443 (49·8%) were women. A CT scan was obtained in 801 (90%) of 890 patients (mean time from symptom onset to scan of 13·4 h (SD 29·8). The incidence of first-ever stroke age-adjusted to the world population was 121·7 (95% CI 113·7-130·1) per 100 000. The age-adjusted incidence rates, per 100 000 inhabitants, by main pathological subtypes were as follows: ischaemic stroke (101·5 [95% CI 90·9-113·0]); intracerebral haemorrhage (17·9 [13·5-23·4]), and subarachnoid haemorrhage (4·2 [2·1-7·3]). The 30-day case-fatality rate was 24·6% (21·9-27·6). At 6 months after the stroke, 55·9% (432 of 773) of cases had died or were disabled, which increased to 61·0% (456 of 747) at 12 months. Health-related quality of life in survivors was low at 6 months, improving slightly at 12 months after the stroke. The incidence of stroke in this low-resource population was higher than our previous finding in northern Chile and within the mid-range of most population-based stroke studies. This result was due mainly to a higher incidence of ischaemic stroke, probably associated with increasing age and a high prevalence of cardiometabolic risk factors in the population studied. Our findings suggest that more should be done for the prevention and care of stroke in communities like the Ñuble population. The National Agency for Research and Development and the Technology-Health Research Fund, Clínica Alemana de Santiago, Boehringer Ingelheim, Bristol Meyers Squibb, The Herminda Martin Clinical Hospital of Chillán, Universidad Mayor, and Universidad de Concepción.

Long-Term Survival after Stroke in 1.4 Million Japanese Population: Shiga Stroke and Heart Attack Registry.

Background and Purpose Although numerous measures for stroke exist, stroke remains one of the leading causes of death in Japan. In this study, we aimed to determine the long-term survival rate after first-ever stroke using data from a large-scale population-based stroke registry study in Japan. MethodsPart of the Shiga Stroke and Heart Attack Registry, the Shiga Stroke Registry is an ongoing population-based registry study of stroke, which covers approximately 1.4 million residents of Shiga Prefecture in Japan. A total 1,880 patients with non-fatal first-ever stroke (among 29-day survivors after stroke onset) registered in 2011 were followed up until December 2016. Five-year cumulative survival rates were estimated using the Kaplan-Meier method, according to subtype of the index stroke. Cox proportional hazards models were used to assess predictors of subsequent all-cause death. ResultsDuring an average 4.3-year follow-up period, 677 patients died. The 5-year cumulative survival rate after non-fatal first-ever stroke was 65.9%. Heterogeneity was present in 5-year cumulative survival according to stroke subtype: lacunar infarction, 75.1%; large-artery infarction, 61.5%; cardioembolic infarction, 44.9%; intracerebral hemorrhage, 69.1%; and subarachnoid hemorrhage, 77.9%. Age, male sex, Japan Coma Scale score on admission, and modified Rankin Scale score before stroke onset were associated with increased mortality during the chronic phase of ischemic and hemorrhagic stroke. ConclusionsIn this study conducted in a real-world setting of Japan, the 5-year survival rate after non-fatal first-ever stroke remained low, particularly among patients with cardioembolic infarction and large-artery infarction in the present population-based stroke registry.

Readmissions and Mortality During the First Year After Stroke-Data From a Population-Based Incidence Study.

Background: After a first-ever-in-a-lifetime stroke (FELS), hospital readmissions are common and associated with increased mortality and morbidity of stroke survivors, thus, raising the overall health burden of stroke. Population-based stroke studies on hospital readmissions are scarce despite it being an important healthcare service quality indicator. We evaluated unplanned readmissions or death during the first year after a FELS and their potential factors, based on a Portuguese community register.Methods: Data were retrieved from a population-based prospective register undertaken in Northern Portugal (ACIN2) in 2009–2011. Retrospective information about unplanned hospital readmissions and case fatality within 1 year after FELS index hospitalization (FELS-IH) was evaluated. Readmission/death-free survival 1 year after discharge was estimated using the Kaplan–Meyer method. Independent risk factors for readmission/death were identified using Cox proportional hazard models.Results: Unplanned readmission/death within 1 year occurred in 120 (31.6%) of the 389 hospitalized FELS survivors. In 31.2% and 33.5% of the cases, it occurred after ischemic stroke or intracerebral hemorrhage, respectively. Infections and cerebrovascular and cardiovascular diseases were the main causes of readmission. Of the readmissions, 65.3% and 52.5% were potentially avoidable or stroke related, respectively. The main cause of potentially avoidable readmissions was the continuation/recurrence of the event responsible for the initial admission or a closely related condition (71.2%). Male sex, age, previous and post-stroke functional status, and FELS-IH length of stay were independent factors of readmission/death within 1 year.Conclusions: Almost one-third of FELS survivors were readmitted/dead 1 year after their FELS-IH. This outcome persisted after the first months after stroke hospitalization in all stroke subtypes. More than half of readmissions were considered potentially avoidable or stroke related.

Traditional Vascular Risk Factors Account for Different Proportions of Ischemic Stroke Within Different Gender and Race Groups

Background Few studies have compared the proportion of ischemic strokes attributable to traditional vascular risk factors (population-attributable risk percent or PAR%) between genders and races. The PAR% is a function of the population prevalence and strength of association of a risk factor. Methods A population-based case-control study of ischemic stroke in young adults ages 18-49 in the Baltimore-Washington region was used to study the prevalence, odds ratios, and PAR% of hypertension, diabetes, and smoking among blacks and whites. Logistic regression was used to calculate age-adjusted odds ratios. All analyses were stratified by gender. Results There were 1044 cases and 1099 controls. Of the cases, 47% were black, 54% were women. Roughly a quarter to a third of all strokes in women were attributable to smoking. Due to the higher prevalence of hypertension and a higher odds ratio for hypertension in black men (OR 3.9, 95% CI 2.6-5.9) compared to white men (OR 1.8, 95% CI 1.3-2.6), there was a much higher PAR% for hypertension among black men than white men. See Table 1 for prevalence and Table 2 for PAR% stratified by gender and race. Conclusion Traditional vascular risk factors have the potential to explain a high proportion of ischemic stroke in young adults. The high proportion of strokes in women attributable to smoking underscores the need for targeted smoking cessation interventions in this population. Diabetes and, especially, hypertension are important contributors to the excess population burden of ischemic stroke among blacks. These findings support the value of early screening and treatment for hypertension in young blacks.

Abstract TP182: Stroke Outcome in Mexican American Immigrants and Non-Immigrants

Background/Objective: We studied the association of being born outside of the U.S. (immigrant) or born in the U.S. (non-immigrant) with 90 day post-stroke outcomes in a population-based stroke study in Texas. Methods: Stroke cases from 2008-2016 were identified from the Brain Attack Surveillance in Corpus Christi (BASIC) project. Outcomes among survivors included ADL/IADL score (higher scores worse) for functional assessment, 3MSE (cognition, lower scores worse), and NIHSS Score (neurologic, higher scores worse). Weighted linear regression models were used to assess the effect of immigration status on the outcomes. Analysis was completed using multiple imputation and inverse probability weighting to account for differential attrition. Results: Of 935 Mexican Americans available for analysis, 83 were immigrants and 852 were non-immigrants. Immigrants had resided in the U.S. on average 47 years. Immigrants were significantly older (69 vs. 66 years), more likely male (60% vs. 49%), more likely to have atrial fibrillation and have less education than non-immigrants (all p&lt;0.05). No differences in hypertension, diabetes, cholesterol, insurance, smoking or other comorbidities existed. The Table provides the data from the fully adjusted models. Immigrants had better functional outcome (mean difference (MD) = -0.22; p=0.02), and no difference for neurologic outcome (MD= -0.15; p=0.15). There was an association of worse cognitive outcome in immigrants (MD= -5.25; p=0.009), however, the association was explained by attenuated after the adjustment for the lower educational attainment in immigrants (MD= -0.79; p=0.64). Conclusions: In this community, there was no evidence of worse stroke outcome among Mexican American immigrants, who had lived in the U.S. for decades, compared with non-immigrants. Further studies of more recent immigrant populations are warranted.

Abstract TMP79: Pre-Stroke Sleep Apnea and Post-Stroke Depression

Introduction: Sleep apnea is an independent risk factor for stroke and strongly associated with depression; however, little is known about its role in predicting depression after stroke among stroke survivors. This study examined the association between pre-stroke sleep apnea risk and depression at 90 days post-stroke in a population-based sample. Methods: Data were obtained from the Brain Attack Surveillance in Corpus Christi (BASIC) project, a population-based stroke study in south Texas. The study sample consisted of 1,383 participants who had ischemic or hemorrhagic stroke between August 2010 and December 2016. Depression after stroke was measured by the 8-item Patient Health Questionnaire (range: 0-24). Participants scoring 10 or above were classified as having depression. Pre-stroke sleep apnea risk assessed at stroke onset was classified as high or low based on Berlin Questionnaire scores (high risk: 2 or more categories with a positive score; low risk: 0-1 category with a positive score). Inverse probability weighting and multiple imputation were used to deal with attrition and missing covariate data. Weighted logistic regression models were used to examine the association between pre-stroke sleep apnea risk and post-stroke depression. Results: Mean age of participants was 68.1 years (SD=12.3), men and women were evenly distributed, 59.4% were Mexican American, and 59.2% were at high risk for sleep apnea before stroke. High-risk participants were significantly more likely to be men, Mexican American, obese and on medication for depression at the time of stroke. Pre-stroke sleep apnea risk was associated with post-stroke depression (Odds Ratio [OR]=1.78, 95% Confidence Interval [CI]=1.38-2.29), even after adjustment for sociodemographic characteristics, smoking, obesity, pre-stroke depression status and stroke severity (OR=1.60, 95% CI=1.19-2.14). Conclusions: Pre-stroke sleep apnea may be an independent risk factor for post-stroke depression. Treatment of sleep apnea before or perhaps even after stroke may reduce risk for depression after stroke.