Time trends in incidence rates of atrial fibrillation-related strokes in Norway 2001–2014: a nationwide analysis using data from the cardiovascular disease in Norway (CVDNOR) project

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
I Ariansen ◽  
J Igland ◽  
M Anjum ◽  
L.J Kjerpeseth ◽  
R Selmer ◽  
...  

Abstract Background Stroke incidence rates declined in Norway during 2001 to 2014. Atrial fibrillation (AF) incidence rates were stable in the same period. Purpose We aimed to study time trends in incidence (first time) of acute stroke hospitalizations and stroke deaths associated with AF in Norway in the period 2001–2014. Methods Nationwide hospital discharge diagnoses in the Cardiovascular Disease in Norway (CVDNOR) database and in the National Patient Registry were linked to the National Cause of Death Registry. All hospitalizations with acute stroke (including ischemic stroke, intracerebral bleeding and unspecified stroke) and out-of-hospital deaths with stroke as underlying cause in individuals 25 years and older were obtained during 1994–2014. Incident stroke was defined as the first hospitalization or out-of-hospital death due to stroke with no hospitalization for acute stroke or stroke sequela the past 7 years. Stroke was defined as AF-related if AF was registered during a hospitalization the past 7 years, or as underlying or contributing cause of death up to 28 days after the stroke hospitalization. Age-standardized incidence rates with 95% confidence intervals (CIs) were calculated using direct standardization to the age-distribution in the Norwegian population per 2001. Age-adjusted average yearly incidence rate ratios (IRR) with 95% CIs were estimated by negative binomial regression analyses. Results From 2001 to 2014 we identified 157 580 incident stroke cases of which 38 317 were AF-related. The proportion of incident strokes that were related to AF increased from 20.6% in 2001 to 26.3% in 2014. Age-standardized incidence rates of AF-related strokes per 100,000 person years were stable at 88 (85, 92) in 2001 and 79 (76, 83) in 2014, corresponding to a 0% average yearly change, IRR 1.00 (0.99, 1.00). The age-standardized incidence rates of non-AF-related strokes per 100,000 person years decreased from 334 (328, 341) in 2001 to 214 (209, 219) in 2014, corresponding to a 3% average yearly decrease, IRR 0.97 (0.97, 0.97). Conclusion The favourable trend in total stroke incidence rates from 2001 to 2014 does not include AF-related strokes. This may suggest that AF has become accountable for a higher proportion of incident strokes or that AF detection improved over this period. Figure 1. Age-standardized incidence rates of stroke hospitalizations or out-of-hospital deaths per 100,000 person years (py) by year, illustrated as all strokes (blue horizontal line) and AF-related strokes (red horizontal line/height of red area). The height of the blue area illustrates the rate for non-AF related strokes. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): Vestre Viken Hospital Trust (public hospital research fund)

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
T Ikeda ◽  
S Ogawa ◽  
T Kitazono ◽  
J Nakagawara ◽  
K Minematsu ◽  
...  

Abstract Background XAPASS is a real-world, prospective, single-arm, observational study conducted as a post-marketing surveillance mandated by the health authority in Japan. Nowadays, direct oral anticoagulant therapy using factor Xa or thrombin inhibitor has been the standard of care for patients with non-valvular atrial fibrillation (NVAF) to prevent ischemic stroke. However, the clinical impact of reduced dosage (approved dose of 15 or 10 mg once daily in Japan is relatively reduced compared to global dosage) factor Xa inhibitor rivaroxaban in high-risk patients remains unclear. Purpose The present sub-analysis of XAPASS was carried out to assess long-term safety and effectiveness of reduced-dose rivaroxaban in high-risk NVAF patients for bleeding and thromboembolism. Methods All patients with NVAF who were newly started on rivaroxaban were eligible for surveillance. The principal safety outcome was a composite of major and non-major bleeding events, and the primary effectiveness outcome was a composite of ischaemic stroke, haemorrhagic stroke, non-central nervous system systemic embolism (non-CNS SE), and myocardial infarction (MI). In this present sub-analysis, high-risk patients were defined as those who had two of the following three risk factors: elderly (≥75 years old), low body weight (≤50 kg), and renal impairment (CrCl <50 mL/min). Results In total, 11,308 patients were enrolled between April 2012 and June 2014 from 1,419 hospitals, and overall data were analysed from 10,664 patients from whom data were collected. Among them, 3,694 patients matched the criteria for the high-risk patients defined in this sub-analysis, and 6,970 patients did not match the criteria (non-high-risk patients). The mean treatment duration was 791±673 days in the high-risk patients and 944±709 days in the non-high-risk patients. Mean patient age was 80.9±5.5 years and 69.0±9.0 years at baseline, respectively. Mean CHADS2 score was 2.8 and 1.8, and CHA2DS2-VASc score was 4.4 and 2.9, respectively. The rates of CHADS2 component comorbidities were lower in the non-high-risk patients except for diabetes mellitus. The incidence rates of any bleeding, major bleeding, and the primary effectiveness outcomes were 4.8, 1.6, and 2.1%/patient-year in the high-risk patients. The incidence rates of these clinical events in the non-high-risk patients were 3.3, 0.9, and 1.0%/patient-year, respectively. Conclusions Incidence rates of long-term bleeding and thromboembolism were higher in the high-risk patients than in the non-high-risk patients. However, the rates of these outcomes using the Japan-specific reduced dose were not so high. Furthermore, the balance between safety and effectiveness outcomes was within an acceptable range. The present study provides useful information for physicians to stratify high-risk patients using the reduced dose in daily clinical practice. Funding Acknowledgement Type of funding source: Private company. Main funding source(s): Bayer Yakuhin Ltd.


2014 ◽  
Vol 112 (08) ◽  
pp. 276-286 ◽  
Author(s):  
Carlos Martinez ◽  
Anja Katholing ◽  
Saul Freedman

SummaryIt was the aim of this study to determine prognosis of incidentally detected ambulatory atrial fibrillation (IA-AF) and its response to antithrombotic therapy. We performed a cohort study of 5,555 patients with IA-AF (mean age 70.9 ± 10.1, 38.4% female) and 24,705 age- and gender-matched controls without AF followed three years using UK Clinical Practice Research Datalink. We measured incidence rates of stroke, all-cause mortality, myocardial infarction, major bleeding, and effect of antithrombotic therapy. Patients with IA-AF had mean CHA2DS2VASc score 2.5 ± 1.5, 73% with score ≥2. The stroke incidence rate (IR) was 19.4 (95% confidence interval 17.1 – 21.9)/1,000 person-years vs 8.4 (7.7 – 9.1) in controls (p<0.001), mortality 40.1 (36.8 – 43.6)/1,000 person-years vs 20.9 (19.8 – 22.0) in controls (p<0.001), and myocardial infarction 9.0 (7.5 – 10.8)/1,000 person-years vs 6.5 (5.9 – 7.2) in controls (p<0.001). IRs of all endpoints increased with age. Oral anticoagulant ± antiplatelet therapy received by 51.0% in year following IA-AF was associated with adjusted hazard ratio (HR) of 0.35 (0.17 – 0.71) for stroke, and 0.56 (0.36 – 0.85) for death compared to no therapy, while antiplatelet treatment was associated with a non-significant reduction of HR: 0.81 (0.51 – 1.29) for stroke, and 0.80 (0.55 – 1.15) for death, though both carried a similar small non-significant adjusted excess IR of major bleeding. In conclusion, asymptomatic AF detected incidentally is associated with a significant adverse effect on stroke and death, with reduction in both associated with oral anticoagulant but not antiplatelet treatment. This provides justification to assess cost-effectiveness of community screening to detect unknown AF.


Heart ◽  
2020 ◽  
pp. heartjnl-2020-316624 ◽  
Author(s):  
Lars Jøran Kjerpeseth ◽  
Jannicke Igland ◽  
Randi Selmer ◽  
Hanne Ellekjær ◽  
Arnljot Tveit ◽  
...  

ObjectiveTo study time trends in incidence of atrial fibrillation (AF) in the entire Norwegian population from 2004 to 2014, by age and sex, and to estimate the prevalence of AF at the end of the study period.MethodsA national cohort of patients with AF (≥18 years) was identified from inpatient admissions with AF and deaths with AF as underlying cause (1994–2014), and AF outpatient visits (2008–2014) in the Cardiovascular Disease in Norway (CVDNOR) project. AF admissions or out-of-hospital death from AF, with no AF admission the previous 10 years defined incident AF. Age-standardised incidence rates (IR) and incidence rate ratios (IRR) were calculated. All AF cases identified through inpatient admissions and outpatient visits and alive as of 31 December 2014 defined AF prevalence.ResultsWe identified 175 979 incident AF cases (30% primary diagnosis, 69% secondary diagnosis, 0.6% out-of-hospital deaths). AF IRs (95% confidence intervals) per 100 000 person years were stable from 2004 (433 (426–440)) to 2014 (440 (433–447)). IRs were stable or declining across strata of sex and age with the exception of an average yearly increase of 2.4% in 18–44 year-olds: IRR 1.024 (1.014–1.034). In 2014, the prevalence of AF in the adult population was 3.4%.ConclusionsWe found overall stable IRs of AF for the adult Norwegian population from 2004 to 2014. The prevalence of AF was 3.4% at the end of 2014, which is higher than reported in previous studies. Signs of an increasing incidence of early-onset AF (<45 years) are worrying and need further investigation.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
E Sharashova ◽  
T Wilsgaard ◽  
J Ball ◽  
E Gerdts ◽  
A Rosengren ◽  
...  

Abstract Background Due to population aging, increasing prevalence of obesity and enhanced detection, the prevalence of atrial fibrillation (AF) worldwide is increasing steadily. Considerable sex differences in the epidemiology of AF such as lower prevalence and later onset in women compared to men have been reported. However, little is known about sex-specific temporal trends in AF incidence within the general population. Purpose To explore sex-specific age-adjusted secular trends in the incidence of AF in a general population from Norway between 1986 and 2014. Methods A total of 16,865 men and 15,413 women aged 20 years or older and without AF were enrolled in a longitudinal population study between 1986 and 2008 and followed up for incident AF to the end of 2014. Follow-up was from the date of attendance to the date of AF, emigration or death, whichever came first. All AF cases were validated by an independent endpoint committee using hospital and death records. AF incidence rates were calculated for each calendar year by dividing the number of AF cases per year by the corresponding person-time at risk. To allow for non-linear time trends, calendar year was fitted using fractional polynomials. Poisson regression was used to estimate calendar year-specific AF incidence rates adjusted for age. All analyses were stratified by sex. Results A total of 911 AF events in women and 1,139 AF events in men occurred over 324,090 person-years and 294,531 person-years of follow-up, respectively. During the study period AF incidence rates in men were at least double that in women (Figure). Age-adjusted AF incidence rates in women increased from 1986, peaked at 0.87 per 1000 person-years in 1998 and then decreased slightly towards 2014. In men AF incidence rates increased up to 2.18 per 1000 person-years in 2005 and then steeply decreased. Conclusion(s) AF incidence rates decreased in both women and men towards the end of the study period. The decrease was more profound in men compared to that in women. One possible explanation is more pronounced reduction in incidence and better treatment of myocardial infarction in men compared to women given that the aetiology of AF in men is mainly ischemic heart disease-related. However, further epidemiological analyses should be undertaken to identify explanatory factors. Funding Acknowledgement Type of funding source: Public hospital(s). Main funding source(s): University Hospital of North Norway, Northern Norway Regional Health Authority


Stroke ◽  
2005 ◽  
Vol 36 (11) ◽  
pp. 2362-2366 ◽  
Author(s):  
Yoko Miyasaka ◽  
Marion E. Barnes ◽  
Bernard J. Gersh ◽  
Stephen S. Cha ◽  
James B. Seward ◽  
...  

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
A.P Benz ◽  
S Aeschbacher ◽  
P Krisai ◽  
S Blum ◽  
P Meyre ◽  
...  

Abstract Background Hospitalization for heart failure and death are among the most common adverse clinical outcomes in patients with atrial fibrillation (AF). The underlying mechanisms are poorly understood. Purpose We hypothesised that inflammation, quantified by plasma levels of C-reactive protein (CRP) and interleukin 6 (IL-6), is independently associated with hospitalization for heart failure and death in a large, contemporary cohort of AF patients. Methods Patients with established AF and 65 years of age or older were enrolled in two large, prospective, multicentre cohort studies in Switzerland. Plasma levels of high-sensitivity (hs) CRP and IL-6 were measured from frozen EDTA plasma samples obtained at baseline. Using these two biomarkers, we calculated an inflammation score ranging from 0 to 4 (1 point for each biomarker between the 50th and 75th percentile, 2 points for each biomarker above the 75th percentile). We constructed multivariable Cox proportional hazards models to quantify the associations of hs-CRP, IL-6 and the inflammation score with time to first hospitalization for heart failure and time to all-cause mortality, respectively. Results A total of 3,784 patients with AF (median age 72 years, 28% women, 24% with a prior history of heart failure and 84% anticoagulation use at baseline) were followed for a median (interquartile range [IQR]) of 4.0 (2.9–5.1) years. The median (IQR) plasma levels of hs-CRP and IL-6 at baseline were 1.64 (0.81–3.69) mg/L and 3.42 (2.14–5.60) pg/mL, respectively. The incidence rates of hospitalization for heart failure and death were 3.04 and 2.80 per 100 person-years, respectively. After multivariable adjustment, both biomarkers were significantly associated with the risk of hospitalization for heart failure (per increase in 1 standard deviation [SD], adjusted hazard ratio [aHR] 1.22, 95% confidence interval [CI] 1.11–1.34 for log-transformed hs-CRP, and aHR 1.48, 95% CI 1.35–1.62 for log-transformed IL-6) and death (per increase in 1 SD, aHR 1.40, 95% CI 1.27–1.54 for log-transformed hs-CRP, and aHR 1.67, 95% CI 1.53–1.81 for log-transformed IL-6). Incidence rates of hospitalization for heart failure increased from 1.34 to 7.31 per 100 person-years across categories of the inflammation score (Figure 1). A strong relationship persisted after multivariable adjustment. Similar findings were observed for all-cause mortality. Conclusions Inflammation is a strong predictor of hospitalization for heart failure and death in patients with AF. Targeting inflammation may be a promising treatment strategy to improve outcomes in these patients at high risk for adverse outcomes. Figure 1 Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): Swiss National Science Foundation


2020 ◽  
Vol 54 (5) ◽  
pp. 427-432
Author(s):  
Isaac Samuels ◽  
Michael T.M. Wang ◽  
Kar Po Chong ◽  
Alan Davis ◽  
Annemarei Ranta ◽  
...  

<b><i>Background:</i></b> In New Zealand, Māori and Pacific people have higher age-adjusted stroke incidence rates, younger age at first stroke, and higher mortality at 12 months than other ethnic groups. We aimed to determine if access to acute stroke reperfusion therapy with intravenous thrombolysis (IVT) or endovascular thrombectomy (EVT) is equitable among ethnic groups. <b><i>Methods:</i></b> Data were obtained from the Northern Region component of the New Zealand Stroke Registry over the 21 months between January 1, 2018 and September 30, 2019. Data recorded included demographic details, self-identified ethnicity, treatment times, and clinical outcomes. National hospital discharge coding of patients admitted with ischemic stroke and stroke unspecified was used to determine the proportion of patients treated by ethnic group. <b><i>Results:</i></b> There were 537 patients normally resident in the Northern Region who received reperfusion therapy: 281 received IVT alone, 123 received EVT after bridging IVT, and 133 received EVT alone. Of the 537 patients treated with IVT or EVT, there were 81 (15.1%) Māori, 78 (14.5%) Pacific, 57 (10.6%) Asian, and 341 (63.5%) NZ European/other ethnicity patients. There were no ethnic differences in treatment process times. When compared with NZ European/others, Māori and Pacific people were younger, and Māori had worse neurological impairment at admission. A higher proportion of Māori were treated with EVT with a trend to higher proportion treated with IVT. Day 90 modified Rankin Scale (mRS) for EVT-treated patients was similar apart from Asian patients who had worse outcome when compared with NZ European/others (mRS 3 vs. 2; <i>p</i> = 0.03). <b><i>Conclusions:</i></b> This study has shown equitable access to acute stroke reperfusion therapies and largely similar outcomes in different ethnic groups in northern New Zealand.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
S Suzuki ◽  
T Yamashita ◽  
M Akao ◽  
K Okumura

Abstract Background Randomized clinical trials demonstrated the efficacy and safety of apixaban in preventing stroke in patients with atrial fibrillation (AF). However, data on distribution of apixaban levels and their relationships with clinical outcomes are limited. Purpose To evaluate the distribution of blood apixaban concentration and its relationship with clinical outcomes. Method The J-ELD AF Registry is a large-scale, multicenter prospective observational study of Japanese non-valvular AF patients aged ≥75 years taking on-label dose (standard dose of 5 mg bid or reduced dose of 2.5 mg bid) of apixaban. Among the entire cohort (3,015 patients from 110 institutions), plasma apixaban levels at trough was measured by anti-Xa assay (Api-AXA) in 943 patients. The 943 patients were divided into 2 groups by the apixaban dose (standard dose [n=431] and reduced dose [n=512]) and each group was further divided into 2 groups with low and high Api-AXA levels compared with the median value. Results In patients with standard dose, the incidence rates (/100 person-years) of stroke or systemic embolism (1.48 and 1.99), bleeding requiring hospitalization (0.98 and 1.49), and total deaths (0.49 and 0.99) were comparable between low and high Api-AXA groups, respectively. In patients with reduced dose, although the incidence rates (/100 person-years) of stroke or systemic embolism (0.84 and 1.68) were comparable, bleeding requiring hospitalization (0.42 and 4.64), and total deaths (2.52 and 6.65) were significantly higher in high Api-AXA group than in low Api-AXA group. Multivariable Cox regression analysis revealed that in patients with reduced dose, high Api-AXA level was independently associated with bleeding requiring hospitalization (HR 12.12, 95% CI: 1.56–94.22, P=0.017) and insignificantly with total deaths (HR 2.15, 95% CI: 0.83–5.55, P=0.116). Conclusions High trough apixaban level in patients with standard dose was not associated with adverse events, while that in patients with reduced dose was associated with bleeding requiring hospitalization and total deaths. Measurement of apixaban levels may be informative in elderly patients indicated for reduced dose possibly with the intent of risk stratification and decision making. Funding Acknowledgement Type of funding source: Other. Main funding source(s): Bristol-Myers Squibb K.K.


2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
M Lehto ◽  
J Haukka ◽  
O Halminen ◽  
P Mustonen ◽  
J Putaala ◽  
...  

Abstract Introduction Atrial fibrillation (AF) is a chronic condition, and once diagnosed, most of the patients need life-long treatment for AF; rate and rhythm control for symptom relief and oral anticoagulation to mitigate the associated risk of stroke. Incidence of AF is strongly associated with age, and with longer life-expectancy the number of AF patients is worldwide rapidly increasing. Purpose The FinACAF study is a nationwide registry study including all AF patients searched from comprehensive national health care registers. To our knowledge, FinACAF is the first nationwide study including both primary, secondary, and tertiary health care register data. The aim of this study was to assess the incidence of new-onset AF in unselected nationwide population in Finland. Methods In the FinACAF study we gathered data (hospitalizations, outpatient specialist and primary health care visits, and drug reimbursement) from all national health care registers to identify new-onset AF patients from 01st January 2004 to 31st December 2018. To minimize the risk of misclassification, we considered a patient to have incident AF only if the new-onset AF diagnosis emerged after 1st January 2007 allowing at least three years of registration in Finnish health care registers without diagnosis of AF. Furthermore, patients with warfarin prescriptions during 2004–2006 were excluded. Raw incidence rates (1/100 000) were calculated using the total number of incident AF cases during a given year as numerator, and the total number of Finnish population free of AF on the last day of that year as denominator. The age-standardized incidence rates (1/100 000) were calculated using the total number of new-onset AF cases per year compared to the Nordic population free of AF age distribution. Results In total, 411 080 patients with the diagnosis of AF were documented during 2004–2018 in Finland, and the number of new-onset AF patients during 2007–2018 was 256 323. The incidence of AF in relation to age is shown in the Figure 1, and the increasing incidence with advancing age is outstandingly seen. Incidence of AF was more than 2000/100 000 in the population 80 years or older. The incidence of new-onset AF in the whole Finnish population increased during the study period from 330/100 000 and peaked to 456/100 000 in 2018. However, after adjustment for age, the age-adjusted AF incidence remained unchanged during 2007–2018 (Figure 2), but an obvious leap in the incidence emerged during 2011–2013 when the national primary care register was established. Conclusions In 2018 the incidence of AF per the whole population was 456/100 000. Based on very novel data and including all the known, diagnosed AF patients in Finland, this is the highest reported incidence rate of AF. Incidence of AF is strongly age-dependent, but the age-standardized incidence was not significantly changed from 2007 to 2018. FUNDunding Acknowledgement Type of funding sources: Public hospital(s). Main funding source(s): Helsinki and Uusimaa Hospital District research fundThe Finnish Foundation for Cardiovascular Research The incidence of AF in relation to age Age-adjusted annual incidence of AF


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
M Akao ◽  
T Yamashita ◽  
S Suzuki ◽  
K Okumura

Abstract Background Randomized clinical trials demonstrated the efficacy and safety of apixaban in preventing stroke in patients with atrial fibrillation (AF). However, data on patients with low creatinine clearance (CCr), especially CCr 15–29 mL/min, are limited. Methods The J-ELD AF Registry is a large-scale, multicenter prospective observational study of Japanese non-valvular AF patients aged ≥75 years taking on-label dose (standard dose of 5 mg bid or reduced dose of 2.5 mg bid) of apixaban. The enrollment period was from September 2015 to August 2016, and the observation period for each patient was 1 year. The entire cohort (3,015 patients from 110 institutions) was divided into three CCr subgroups: CCr ≥50 mL/min (n=1,165, 38.6%), CCr 30–49 mL/min (n=1,395, 46.3%), and CCr 15–29 mL/min (n=455, 15.1%). Results Most patients (74.3%) in the CCr ≥50 group received the standard apixaban dose, and most (97.4%) in the CCr 15–29 group received the reduced apixaban dose. The average age was 79.2 years for the CCr ≥50 group, 82.5 years for the CCr 30–49 group, and 85.6 years for the CCr 15–29 group. The lower CCr value group included more female patients, had lower body weight, and less cases of paroxysmal AF, as well as more cases of heart failure, peripheral artery disease, and myocardial infarction as comorbidities. The CHA2DS2-VASc and HAS-BLED scores were 4.2±1.2 and 2.4±0.8 for the CCr ≥50 group, 4.5±1.2 and 2.4±0.8 for the CCr 30–49 group, and 4.9±1.2 and 2.4±0.7 for the CCr 15–29 group, respectively. Kaplan Meier curves for cumulative incidence of events are shown in Figure. The event incidence rates (/100 person-years) were 1.76, 1.39, and 1.67 for stroke or systemic embolism (log rank p=0.762), 1.39, 1.93, and 3.13 for bleeding requiring hospitalization (log rank p=0.159), 1.75, 2.76, and 7.87 for total deaths (log rank p&lt;0.001), and 0.46, 0.84, and 2.62 for cardiovascular deaths (log rank p&lt;0.001), in the CCr ≥50 group, CCr 30–49 group, and CCr 15–29 group, respectively. After adjusting for confounders by Cox regression analysis, CCr 15–29 was an independent risk for total death [hazard ratio (HR) 3.22, 95% confidence interval (CI) 1.68–6.17, with reference to the CCr ≥50 group] and cardiovascular death [HR 3.18, 95% CI 1.06–9.56], but not for stroke or systemic embolism [HR 0.94, 95% CI 0.40–2.24], or bleeding requiring hospitalization [HR 2.00, 95% CI 0.93–4.28]. Conclusions The incidence of events in each CCr value group was comparable for stroke or systemic embolism and bleeding requiring hospitalization, and significantly higher for total deaths and cardiovascular deaths only in the CCr 15–29 group, in Japanese non-valvular AF patients aged ≥75 years. Cumulative incidence rates of events Funding Acknowledgement Type of funding source: Private company. Main funding source(s): Bristol-Myers Squibb


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