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There is limited data on long-term outcomes after hospitalization for ACS. We aimed to estimate the rate of recurrent cardiovascular events in the long-term, in a population-based, unselected cohort of ACS patients. We included 1379 patients with ACS hospitalized at Östersund hospital 2010–2014 and followed them from the day after discharge to 31 December 2017. The primary endpoint was the unadjusted rate of the composite of CV death, AMI and ischemic stroke. Risk factors for the primary endpoint were assessed in a multivariable Cox proportional hazards regression model. During a median follow-up of 4.7 years, the unadjusted rate of the primary endpoint was 10.3% at 1 year and 28.6% at the end of follow-up. Predictors of increased risk for subsequent events were congestive heart failure, diabetes mellitus, angina pectoris, prior revascularization with PCI or CABG and treatment with diuretics at discharge. Lipid-lowering therapy at discharge and revascularization with PCI or CABG were associated with a lower risk of recurrent events. The risk of recurrent cardiovascular was high at 1 year and continued to be so during the following almost 3 years of median follow-up. Established predictors of cardiovascular risk were confirmed.

Data are scarce on long-term outcomes after ischemic stroke (IS) or transient ischemic attack (TIA). In this prospective cohort study, we examined the cumulative incidence of major adverse cardiovascular events (MACE) after IS and TIA using a competing risk model and factors associated with new events using a Cox-proportional hazard regression model. All patients discharged alive from Östersund Hospital with IS or TIA between 2010 and 2013 (n = 1535) were followed until 31 December 2017. The primary endpoint was a composite of IS, type 1 acute myocardial infarction (AMI), and cardiovascular (CV) death. Secondary endpoints were the individual components of the primary endpoint, in all patients and separated in IS and TIA subgroups. The cumulative incidence of MACE (median follow-up: 4.4 years) was 12.8% (95% CI: 11.2–14.6) within 1 year after discharge and 35.6% (95% CI: 31.8–39.4) by the end of follow-up. The risk of MACE and CV death was significantly increased in IS compared to TIA (p-values < 0.05), but not the risk of IS or type 1 AMI. Age, kidney failure, prior IS, prior AMI, congestive heart failure, atrial fibrillation, and impaired functional status, were associated with an increased risk of MACE. The risk of recurring events after IS and TIA is high. IS patients have a higher risk of MACE and CV death than TIA patients.

Background: Bleeding complications following acute coronary syndrome (ACS) have attracted considerable attention in recent years. The gradual implementation of new evidence-based treatments in patients with ACS, with a focus on anti-ischemic therapy, has reduced the risk of ischemic events (new myocardial infarction or ischemic stroke) but at the expense of increased bleeding risk. Bleeding is associated with both increased morbidity and mortality and, with major bleeding, the risk of death is comparable to that seen in myocardial infarction. Avoidance of bleeding is one possible way to further improve post-ACS outcomes. During the 1990s reperfusion approaches shifted from thrombolysis, with its increased risk of bleeding and intracranial hemorrhage (ICH), to percutaneous coronary intervention (PCI), with an expected lower risk. Treatment recommendations are derived from randomized controlled trials in which high-risk patients are excluded, and observational studies are needed to assess outcomes. Antithrombotic treatment is associated with increased risk of serious bleeding and even more so with the new potent P2Y12 inhibitors. However, their association with ICH is not well studied, and knowledge is limited regarding temporal trends in ICH after ACS. Furthermore, few studies have long-term follow-up for serious bleedings and associated risk factors.

Aims: The aims of this thesis were to assess the incidence, temporal trends and factors associated with ICH after acute myocardial infarction (AMI); investigate the impact on ICH risk of changing the treatment regimen from clopidogrel to ticagrelor; estimate the risk of serious bleeding (bleeding requiring hospitalization) after ACS and characterize the type of bleeding; identify factors associated with increased bleeding risk; and assess if serious bleeding is associated with increased mortality. 

Method: In studies I–III, patients with AMI were identified using the Register of Information and Knowledge About Swedish Heart Intensive Care Admission (RIKS-HIA), and the data were combined with information from the Swedish National Patient Register, 1998–2013 to identify ICH. In study II, we included a matched reference group from Statistics Sweden. Study IV included all patients who were identified with an ACS during the inclusion period of the Nurse-Based Age-Independent Intervention to Limit Evolution of Disease After Acute Coronary Syndrome risk factor trial (2010–2014), and patients were followed until December 2017. Serious bleedings were identified in the local diagnosis registry, and scrutinizing of the medical records validated all diagnoses. Baseline characteristics in all studies were evaluated using the student t-test, Mann–Whitney U test, or the chi-square test as appropriate. In studies I and II, the observational time was divided into periods and in study I the chi-square test for trend was used to evaluate the trend over time. Temporal trends in study II were assessed by Kaplan–Meier analysis and evaluated using log-rank test. To reduce selection bias related to the choice of antiplatelet treatment in study III, the date of the first prescription of ticagrelor was identified in the RIKS-HIA registry and used as a cutoff point, and the study period was divided into two periods of similar length to create two cohorts. The risk in the first with respect to the second cohort was assessed by Kaplan–Meier analysis, and cohorts were compared with the log-rank test. Kaplan–Meier analysis was also used in study IV to assess serious bleeds. Predictors were assessed by Cox regression analyses.  

Results: The 30-day risk of hemorrhagic stroke decreased from 0.2% in 1998 to 0.1% in 2008. The decrease can be explained by the shift in reperfusion method from thrombolysis to PCI in patients with a ST-elevation myocardial infarction. Age, hypertension and previous hemorrhagic stroke were associated with increased risk. The cumulative incidence of ICH within one year of AMI was 0.35%, which did not change during the 13-year follow-up (1998–2010) despite a considerable increase in the use of dual antiplatelet therapy. The incidence of ICH in the AMI cohort was twice that of a matched reference group. Age, decreased kidney function and previous ischemic and hemorrhagic stroke were associated with increased ICH risk. None of the medications included in the analysis were associated with a significant change in ICH risk. For antiplatelets, ticagrelor is a more potent P2Y12 inhibitor compared to clopidogrel and has previously been associated with increased bleeding risk; however, in this work ticagrelor was not associated with increased risk of ICH compared to clopidogrel. In study IV, during a median follow-up of 4.6 years, 8.6% of patients had a serious bleed after their ACS. This rate was 13.4% in patients aged ≥75 years.  The most common location was gastrointestinal, followed by ICH. Risk factors associated with serious bleeding were age ≥75 years, hypertension, and previous heart failure. Bleeding per se was not associated with increased mortality.

Conclusion:  The shift in reperfusion method from thrombolysis to PCI likely explained the decrease in ICH in the acute phase after an AMI. The incidence of ICH post-discharge was stable over the study period despite increased use of antithrombotic therapy, and the use of more potent P2Y12 inhibitor did not increase the ICH risk. Serious bleeding was relatively frequent in the long term after ACS, and bleeding recurrence was common. Important risk factors for bleeding were age, hypertension, previous ischemic or hemorrhagic stroke, decreased renal function and previous heart failure. Individualized assessment of risk factors and comorbidity and individualized intensity and duration of antithrombotic treatment may further improve outcome in ACS patients. Continuous re-evaluation of bleeding risk is needed.

Progress in decreasing ischemic complications in acute coronary syndrome (ACS) has come at the expense of increased bleeding risk. We estimated the long-term, post-discharge incidence of serious bleeding, characterized bleeding type, and identified predictors of bleeding and its impact on mortality in an unselected cohort of patients with ACS. In this population-based study, we included 1379 patients identified with an ACS, 2010–2014. Serious bleeding was defined as intracranial hemorrhage (ICH), bleeding requiring hospital admission, or bleeding requiring transfusion or surgery. During a median 4.6-year follow-up, 85 patients had ≥ 1 serious bleed (cumulative incidence, 8.6%; 95% confidence interval (CI) 8.3–8.9). A subgroup of 557 patients, aged ≥ 75 years had a higher incidence (13.4%) than younger patients (6.0%). The most common bleeding site was gastrointestinal (51%), followed by ICH (27%). Sixteen percent had a recurrence. Risk factors for serious bleeding were age ≥ 75 years, lower baseline hemoglobin (Hb) value, previous hypertension or heart failure. Serious bleeding was associated with increased mortality. Bleeding after ACS was fairly frequent and the most common bleeding site was gastrointestinal. Older age, lower baseline Hb value, hypertension and heart failure predicted bleeding. Bleeding did independently predict mortality.

Enhanced follow-up is needed to improve the results of secondary preventive care in patients with established cardiovascular disease. We examined the effect of long-term, nurse-based, secondary preventive follow-up by telephone on the recurrence of cardiovascular events. Open, randomised, controlled trial with two parallel groups. Between 1 January 2010 and 31 December 2014, consecutive patients (n = 1890) admitted to hospital due to stroke, transient ischaemic attack (TIA), or acute coronary syndrome (ACS) were included. Participants were randomised (1:1) to nurse-based telephone follow-up (intervention, n = 944) or usual care (control, n = 946) and followed until 31 December 2017. The primary endpoint was a composite of stroke, myocardial infarction, cardiac revascularisation, and cardiovascular death. The individual components of the primary endpoint, TIA, and all-cause mortality were analysed as secondary endpoints. The assessment of outcome events was blinded to study group assignment. After a mean follow-up of 4.5 years, 22.7% (n = 214) of patients in the intervention group and 27.1% (n = 256) in the control group reached the primary composite endpoint (HR 0.81, 95% CI 0.68–0.97; ARR 4.4%, 95% CI 0.5–8.3). Secondary endpoints did not differ significantly between groups. Nurse-based secondary preventive follow-up by telephone reduced the recurrence of cardiovascular events during long-term follow-up.

Background and Purpose: Guidelines recommend dual antiplatelet treatment with ticagrelor instead of clopidogrel after acute myocardial infarction. Ticagrelor increases major and minor noncoronary artery bypass graft bleeding compared with clopidogrel, but whether the risk of intracranial hemorrhage (ICH) increases is unknown. We aimed to examine any association between ticagrelor and ICH and to identify predictors of ICH among unselected patients after acute myocardial infarction.

Methods: Patients with acute myocardial infarction were identified using the Register of Information and Knowledge About Swedish Heart Intensive Care Admissions, and the data were combined with the Swedish National Patient Registry to identify ICH occurrence. To avoid obvious selection bias related to the choice of dual antiplatelet treatment, we divided the study cohorts into 2 time periods of similar length using the first prescription of ticagrelor as a cutoff point (December 20, 2011). The risk of ICH during the first period (100% clopidogrel treatment) versus the second period (52.1% ticagrelor and 47.8% clopidogrel treatment) was assessed using Kaplan-Meier analysis. Cox proportional-hazards regression analyses, with assessment of interactions between all significant variables, were used to identify predictors of ICH.

Results: The analysis included 47 674 patients with acute myocardial infarction. The cumulative incidence of ICH during the first period was 0.59% (91 cases [95% CI, 0.49-0.69]) versus 0.52% (97 cases [95% CI, 0.43-0.61]) during the second period (P=0.83). In multivariable Cox analysis, study period (second versus first period) was not predictive of ICH. Interaction analyses showed that age and prior cardiovascular morbidities were of importance in predicting the risk of ICH.

Conclusions: The increased use of ticagrelor was not associated with ICH, whereas age and prior cardiovascular morbidities were related to the risk of ICH and interacted significantly.

BACKGROUND: To address the lack of knowledge regarding the long-term risk of intracranial hemorrhage (ICH) after acute myocardial infarction (AMI), the aims of this study were to: (1) investigate the incidence, time trends, and predictors of ICH in a large population within 1 year of discharge after AMI; (2) investigate the comparative 1-year risk of ICH in AMI patients and a reference group; and (3) study the impact of previous ischemic stroke on ICH risk in patients treated with various antithrombotic therapies.

METHODS AND RESULTS: Data about patients whose first AMI occurred between 1998 and 2010 were collected from the Swedish Register of Information and Knowledge about Swedish Heart-Intensive-Care Admissions (RIKS-HIA). Patients with an ICH after discharge were identified in the National Patient Register. Risk was compared against a matched reference population. Of 187 386 patients, 590 had an ICH within 1 year. The 1-year cumulative incidence (0.35%) was approximately twice that of the reference group, and it did not change significantly over time. Advanced age, previous ischemic or hemorrhagic stroke, and reduced glomerular filtration rate were associated with increased ICH risk, whereas female sex was associated with a decreased risk. Previous ischemic stroke did not increase risk of ICH associated with single or dual antiplatelet therapy, but increased risk with anticoagulant therapy.

CONCLUSION: The 1-year incidence of ICH after AMI remained stable, at ≈0.35%, over the study period. Advanced age, decreased renal function, and previous ischemic or hemorrhagic stroke are predictive of increased ICH risk.

Background/objectives: Hemorrhagic stroke is a rare but serious complication after an acute myocardial infarction (AMI). The aims of our study were to establish the incidence, time trends and predictors of risk for hemorrhagic stroke within 30 days after an AMI in 1998-2008. Methods: We collected data from the Register of Information and Knowledge about Swedish Heart Intensive Care Admissions (RIKS-HIA). All patients with a myocardial infarction 1998-2008 were included, n = 173,233. The data was merged with the National Patient Register in order to identify patients suffering a hemorrhagic stroke. To identify predictors of risk we used Cox models. Results: Overall the incidence decreased from 0.2% (n = 94) in 1998-2000 to 0.1% (n = 41) in 2007-2008. In patients with ST-elevation myocardial infarction the corresponding incidences were 0.4% (n = 76) in 1998-2000 and 0.2% (n = 21) in 2007-2008, and after fibrin specific thrombolytic treatment 0.6% and 1.1%, respectively, with a peak of 1.4% during 2003-2004. In total 375 patients (0.22%) suffered a hemorrhagic stroke within 30 days of the AMI. The preferred method of reperfusion changed from thrombolysis to percutaneous coronary intervention (PCI). Older age (hazard ratio (HR) >65- <= 75 vs <= 65 years 1.84, 95% confidence interval (CI) 1.38-2.45), thrombolysis (HR 6.84, 95% CI 5.51-8.48), history of hemorrhagic stroke (HR 12.52, CI 8.36-18.78) and prior hypertension (HR 1.52, CI 1.23-1.86) independently predicted hemorrhagic stroke within 30 days. Conclusions: The rate of hemorrhagic stroke within 30 days of an AMI has decreased by 50% between 1998 and 2008. The main reason is the shift in reperfusion method from thrombolysis to PCI. 

BACKGROUND: Secondary prevention after acute coronary syndrome (ACS) is essential to reduce morbidity and mortality, but related studies have been fairly small or performed as clinical trials with non-representative patient selection. Long-term follow-up data are also minimal. A nurse-led follow-up for risk factor improvement may be effective, but the evidence is limited.

OBJECTIVE: The aims of this study are to perform an adequately sized, nurse-led, long-term secondary preventive follow-up with inclusion of an unselected population of ACS patients. The focus will be on lipid and blood pressure control as well as tobacco use and physical activity.

METHODS: The study will consist of a randomized, controlled, long-term, population-based trial with two parallel groups. Patients will be included during the initial hospital stay. Important outcome variables are total cholesterol, low-density lipoprotein (LDL) cholesterol, and sitting systolic and diastolic blood pressure. Outcomes will be measured after 12, 24, and 36 months of follow-up. Trained nurses will manage the intervention group with the aim of achieving set treatment goals as soon as possible. The control group will receive usual care. At least 250 patients will be included in each group to reliably detect a difference in mean LDL of 0.5 mmol/L and in mean systolic blood pressure of 5 mmHg.

RESULTS: The study is ongoing and recruitment of participants will continue until December 31, 2014.

CONCLUSIONS: This study will test the hypothesis that a nurse-led, long-term follow-up after an ACS with a focus on achieving treatment goals as soon as possible is an effective secondary preventive method. If proven effective, this method could be implemented in general practice at a low cost.

TRIAL REGISTRATION: International Standard Randomized Controlled Trial Number (ISRCTN): 96595458; http://www.controlled-trials.com/ISRCTN96595458 (Archived by WebCite at http://www.webcitation.org/6RlyhYTYK).