Education and Age in Return to Work After Ischemic Stroke: A Danish Nationwide Registry-based Cohort Study.

OBJECTIVES: To investigate return to work and workforce detachment in ischemic stroke, including the association with age and level of education. METHODS: Patients in the workforce aged 18 to 60 with first-time ischemic stroke between 1997 and 2017 were identified in Danish registers and followed for 5 years. The cumulative incidence of return to work and subsequent workforce detachment was computed overall and stratified according to age group and education level. Cox regression analysis was used for multivariate analysis. RESULTS: A total of 28,325 patients were included (median age 52.3 (interquartile range (IQR) 46.1 to 56.6) and 64.3% male). After 1 year, 62.0% were in the workforce, highest in age group 18 to 30 (80.0%) and lowest in patients aged 51 to 60 (58.5%). One-year cumulative incidence of return to work overall was 73.4% (20,475), highest in the young age group (87.0%, 76.7%, 74.5%, and 71.3% for age group 18 to 30, 31 to 40, 41 to 50, and 51 to 60, respectively) and high education (80.3%, 72.1%, and 71.3% for long higher, basic or vocational education, respectively). One-year cumulative incidence of subsequent workforce detachment was 25.6% (5248), lowest in young age (22.4%, 23.1%, 24.1%, and 27.2% for age groups 18 to 30, 31 to 40, 41 to 50, and 51 to 60, respectively) and high level of education (13.0%, 28.4%, and 27.2% for long higher, basic, and vocational education, respectively). During the full follow-up, 10,855 (53.0%) left the workforce again. CONCLUSIONS: A high proportion of patients returned to work within 1 year, but more than half left the workforce again. Young age and long education were associated with a higher incidence of return to work and lower subsequent workforce detachment.

Workforce Attachment after Ischemic Stroke - The Importance of Time to Thrombolytic Therapy.

OBJECTIVES: The ability to remain in employment addresses an important consequence of stroke beyond the usual clinical parameters. However, data on the association between time to intravenous thrombolysis and workforce attachment in patients with acute ischemic stroke are sparse. MATERIALS AND METHODS: In this nationwide cohort study, stroke patients of working age (18-60 years) treated with thrombolysis (2011-2016) who were part of the workforce prior to admission and alive at discharge were identified using the Danish Stroke Registry. The association between time to thrombolysis and workforce attachment one year later was examined with multivariable logistic regression. RESULTS: The study population comprised 1,329 patients (median age 51 years [25th-75th percentile 45-56], 67.3% men). The median National Institutes of Health Stroke Scale score at presentation was 4 (25th-75th percentile 2-8), and the median time from symptom-onset to initiation of thrombolysis was 140min (25th-75th percentile 104-196min). The proportion of patients who were part of the workforce at one-year follow-up was 64.6%, 64.3%, 64.9%, and 60.0% in patients receiving thrombolysis within 90min, between 91-180min, between 181-270min, and after 270min, respectively. In adjusted analysis, time to thrombolysis between 91-180min, 181-270min, and >270min was not significantly associated with workforce attachment compared with thrombolysis received ≤90min of symptom-onset (ORs 0.89 [95%CI 0.60-1.31], 0.93 [0.66-1.31], and 0.80 [0.43-1.52], respectively). CONCLUSIONS: In patients of working age admitted with stroke and treated with thrombolysis, two out of three were part of the workforce one year after discharge. There was no graded relationship between time to thrombolysis and the likelihood of workforce attachment.

Thyroid dysfunction and electrocardiographic changes in subjects without arrhythmias: a cross-sectional study of primary healthcare subjects from Copenhagen.

OBJECTIVE: The objective of the present study was to investigate associations of both overt and subclinical thyroid dysfunction with common ECG parameters in a large primary healthcare population. DESIGN: Cross-sectional study. SETTING AND PARTICIPANTS: The study population comprised of primary healthcare patients in Copenhagen, Denmark, who had a thyroid function test and an ECG recorded within 7 days of each other between 2001 and 2011. DATA SOURCES: The Danish National Patient Registry was used to collect information regarding baseline characteristics and important comorbidities. OUTCOME MEASURE AND STUDY GROUPS: Common ECG parameters were determined using Marquette 12SL software and were compared between the study groups. The study population was divided into five groups based on their thyroid status. Euthyroid subjects served as the reference group in all analyses. RESULTS: A total of 132 707 patients (age 52±17 years; 50% female) were included. Hyperthyroidism was significantly associated with higher heart rate and prolonged QTc interval with significant interaction with age (p<0.009) and sex (p<0.001). These associations were less pronounced for patients with higher age. Subclinical hyperthyroidism was associated with higher heart rate among females, and a similar trend was observed among males. Hypothyroidism was associated with slower heart rate and shorter QTc but only in women. Moreover, longer P-wave duration, longer PR interval and low voltage were observed in patients with both subclinical and overt hypothyroidism. However, the presence of low voltage was less pronounced with higher age (p=0.001). CONCLUSION: Both overt and subclinical thyroid disorders were associated with significant changes in important ECG parameters. Age and gender have significant impact on the association of thyroid dysfunction particularly on heart rate and QTc interval.

Incidence of new onset cancer in patients with a myocardial infarction - a nationwide cohort study.

BACKGROUND: Few studies have suggested that patients with myocardial infarction (MI) may be at increased risk of cancer, but further large register-based studies are needed to evaluate this subject. The aim of this study was to assess the incident rates of cancer and death by history of MI, and whether an MI is independently associated with cancer in a large cohort study. METHOD: All Danish residents aged 30-99 in 1996 without prior cancer or MI were included and were followed until 2012. Patients were grouped according to incident MI during follow-up. Incidence rates (IR) of cancer and death in individuals with and without MI and incidence rate ratios (IRR, using multivariable Poisson regression analyses) of cancer associated with an MI were calculated. RESULTS: Of 2,871,168 individuals, 122,275 developed an MI during follow-up, 11,375 subsequently developed cancer (9.3%, IR 19.1/1000 person-years) and 65,225 died (53.3%, IR 106.0/1000 person-years). In the reference population, 372,397 developed cancer (13.0%, IR 9.3/1000 person-years) and 753,767 died (26.3%, IR 18.2/1000 person-years). Compared to the reference population, higher IRs of cancer and death were observed in all age groups (30-54, 55-69 and 70-99 years) and time since an MI (0-1, 1-5 and 5-17 years) in the MI population. MI was associated with an increased risk of overall cancer (IRR 1.14, 95% CI 1.10-1.19) after adjusting for age, sex and calendar year, also when additionally adjusting for chronic obstructive pulmonary disease, hypertension, dyslipidemia, diabetes and socioeconomic status (IRR 1.08, 95% CI 1.03-1.13), but not after further adjustment for the first 6 months post-MI (IRR 1.00, 95% CI 0.96-1.05). CONCLUSION: Patients after an MI have increased incidence of cancer, which may be explained by mutual risk, occult cancers and increased surveillance. Focus on risk factor management to reduce cancer and MI is warranted.

Risk of incident atrial fibrillation in patients presenting with retinal artery or vein occlusion: a nationwide cohort study.

BACKGROUND: The inter-relationships of atrial fibrillation (AF) to retinal vascular occlusions (whether retinal artery occlusion (RAO) or retinal venous occlusion (RVO)) remain unclear. It is unknown if a presentation of retinal artery or venous occlusions may indicate a new onset cardiac arrhythmia. To shed light on this association, we investigated the risk of new onset AF in patients with known RAO and RVO. METHODS: Patients with retinal occlusions from 1997 to 2011 were identified through Danish nationwide registries and matched 1:5 according to sex and age. Cumulative incidence and unadjusted rates of AF according to retinal vascular occlusions (i.e. RAO or RVO) were determined. Hazard ratios (HR) of AF according to retinal vascular occlusion were adjusted for hypertension, diabetes, vascular disease and prior stroke/systemic thromboembolism/transient ischemic attack. RESULTS: One thousand three hundred sixty-eight cases with retinal vascular occlusions were identified (median age 71.4 (inter quartile range (IQR); 61.2-79.8), 47.3% male). RAO constituted 706 cases (51.6%) and RVO 529 (38.7%). The rate of incident AF amongst all cases with retinal vascular occlusion was 1.74 per 100 person-years (95% confidence interval (CI), 1.47-2.06) compared to 1.22 (95% CI, 1.12-1.33) in the matched control group. The rate of AF in RAO was 2.01 (95% CI, 1.6-2.52) and 1.52 (1.15-2.01) in RVO. HRs of incident AF adjusted for cardiovascular comorbidities were 1.26 (95% CI; 1.04-1.53, p = 0.019) for any retinal vascular occlusion, 1.45 (95% CI; 1.10-1.89, p = 0.015) for RAO, and 1.02 (95% CI; 0.74-1.39, p = 0.920) for RVO. CONCLUSIONS: A new diagnosis of retinal vascular occlusion in patients without prior AF was associated with increased risk of incident AF, particularly amongst patients with RAO. Awareness of AF in patients with retinal vascular occlusions is advised.

Risk and benefit of dual antiplatelet treatment among non-revascularized myocardial infarction patients in different age groups.

BACKGROUND: Dual anti-platelet treatment with clopidogrel and aspirin is indicated for most patients after myocardial infarction. We examined the risk/benefit relationship of dual anti-platelet treatment according to age in a nationwide cohort of 30,532 myocardial infarction patients without revascularization. METHODS: Patients admitted with first-time myocardial infarction in 2002-2010, not undergoing revascularization, were identified from nationwide Danish registers. Dual anti-platelet treatment use was assessed by claimed prescriptions. Stratified into age groups, risk of bleeding, all-cause mortality and a combined endpoint of cardiovascular death, recurrent myocardial infarction and ischaemic stroke was analysed by Cox proportional-hazard models and tested in a propensity-score matched population. RESULTS: A total of 21,302 users and 9230 non-users of dual anti-platelet treatment were included (mean age 67.02 (±13.8) years and 64.7% males). Use of dual anti-platelet treatment decreased with age: 80% (<60 years), 76% (60-69 years), 66% (70-79 years) and 52% (>79 years). We found a reduced risk of cardiovascular death, recurrent myocardial infarction and ischaemic stroke in users <60 years (Hazard ratio (HR) =0.69; 95% confidence interval (CI) 0.59-0.80), 60-69 years (HR=0.64; 95% CI 0.56-0.73), 70-79 years (HR=0.80; 95% CI 0.72-0.89) and >79 years (HR=0.92; 95% CI 0.84-1.01, NS). Risk of bleeding increased with dual anti-platelet treatment use in patients aged <60 years (HR=1.63; 95% CI 1.17-2.26), 60-69 years (HR=1.22; 95% CI 0.97-1.59, NS), 70-79 years (HR=1.42; 95% CI 1.17-1.72) and >79 years (HR=1.46; 95% CI 1.22-1.74). Similar tendencies in all four age groups were found in the propensity-matched population. CONCLUSION: Dual anti-platelet treatment use was less likely among elderly patients although similar effects regarding both risk and benefit were found in all age groups. Increased focus on initiating dual anti-platelet treatment in elderly, non-invasively treated myocardial infarction patients is warranted.

Atrial fibrillation and risk of stroke: a nationwide cohort study.

AIM: Although the relation between stroke risk factors and stroke in patients with atrial fibrillation (AF) has been extensively examined, only few studies have explored the association of AF and the risk of ischaemic stroke/systemic thromboembolism/transient ischaemic attack (stroke/TE/TIA) in the presence of concomitant stroke risk factors. METHODS AND RESULTS: From nationwide registries, all persons who turned 50, 60, 70, or 80 from 1997 to 2011 were identified. Persons receiving warfarin were excluded. The absolute risk of stroke/TE/TIA was reported for a 5-year period, as was the absolute risk ratios for AF vs. no AF according to prior stroke and the number of additional risk factors. The study cohort comprised of 3 076 355 persons without AF and 48 189 with AF. For men aged 50 years, with no risk factors, the 5-year risk of stroke was 1.1% (95% confidence interval 1.1-1.1); with AF alone 2.5% (1.8-3.2); with one risk factor and no prior stroke or AF 2.5% (2.3-2.7); and with one factor, no prior stroke and AF 2.9% (1.4-4.3). In men aged 50 years with prior stroke as the only risk factor, 5-year risk was 10.2% (9.1-11.3). In men aged 70 years, the corresponding risks were 4.8% (4.7-4.9), 6.8% (5.7-7.9), 6.6% (6.3-6.8), 8.7 (7.4-9.9), and 19.1% (18.1-20.1), respectively. In women aged 50 years, the risk was of 0.7% (0.7-0.7), 2.1% (0.9-3.2), 1.6% (1.4-1.8), 4.1% (0.6-7.6), and 7.2% (6.3-8.2), respectively, and in women aged 70 years 3.4% (3.3-3.5), 8.2% (7.0-9.5), 4.6% (4.4-4.8), 9.1% (7.5-10.6), and 15.4% (14.5-16.4), respectively. CONCLUSIONS: Stroke/TE/TIA risk was particularly increased when prior stroke/TE/TIA was present. Atrial fibrillation is associated with an increase in risk of stroke/TE/TIA in the absence of other risk factors but only a moderate increase in risk when other risk factors are present.

Comparison of antiplatelet regimens in secondary stroke prevention: a nationwide cohort study.

BACKGROUND: In patients with ischemic stroke of non-cardioembolic origin, acetylsalicylic acid, clopidogrel, or a combination of acetylsalicylic acid and dipyridamole are recommended for the prevention of a recurrent stroke. The purpose of this study was to examine the risk of bleeding or recurrent stroke associated with these three treatments. METHODS: Patients who were discharged with first-time ischemic stroke from 2007-2010, with no history of atrial fibrillation were identified from Danish nationwide registries. Hazard ratios (HRs) and 1-year risks of recurrent ischemic stroke and bleeding were calculated for each antiplatelet regimen. RESULTS: Among patients discharged after first-time ischemic stroke, 3043 patients were treated with acetylsalicylic acid, 12,295 with a combination of acetylsalicylic acid and dipyridamole, and 3885 with clopidogrel. Adjusted HRs for clopidogrel versus the combination of acetylsalicylic acid and dipyridamole were 1.02 (95% confidence interval [CI]: 0.89-1.17) for ischemic stroke and 1.06 (95% CI: 0.83-1.35) for bleeding. Adjusted HRs for acetylsalicylic acid versus the combination of acetylsalicylic acid and dipyridamole were 1.48 (95% CI: 1.31-1.67) for stroke and 1.47 (95% CI: 1.18-1.82) for bleeding. Clopidogrel versus acetylsalicylic acid yielded HRs of 0.69 (95% CI: 0.59-0.81) and 0.72 (95% CI: 0.55-0.96) for stroke and bleeding, respectively. The 1-year predicted risks associated with acetylsalicylic acid, the combination of acetylsalicylic acid and dipyridamole, and clopidogrel were 11.1 (95% CI: 10.2-12.2), 7.7 (95% CI: 7.3-8.3), and 8.0 (95% CI: 6.9-8.7) for ischemic stroke, respectively; while, the risks for bleeding were 3.4 (95% CI: 2.8-3.9), 2.4 (95% CI: 2.1-2.7), and 2.4 (95% CI: 1.9-2.9), respectively. CONCLUSION: Clopidogrel and the combination of acetylsalicylic acid and dipyridamole were associated with similar risks for recurrent ischemic stroke and bleeding; whereas acetylsalicylic acid was associated with higher risks for both ischemic stroke and bleeding. The latter finding may partially be explained by selection bias.

Time elapsed after ischemic stroke and risk of adverse cardiovascular events and mortality following elective noncardiac surgery.

IMPORTANCE: The timing of surgery in patients with recent ischemic stroke is an important and inadequately addressed issue. OBJECTIVE: To assess the safety and importance of time elapsed between stroke and surgery in the risk of perioperative cardiovascular events and mortality. DESIGN, SETTING, AND PARTICIPANTS: Danish nationwide cohort study (2005-2011) including all patients aged 20 years or older undergoing elective noncardiac surgeries (n=481,183 surgeries). EXPOSURES: Time elapsed between stroke and surgery in categories and as a continuous measure. MAIN OUTCOMES AND MEASURES: Risk of major adverse cardiovascular events (MACE; including ischemic stroke, acute myocardial infarction, and cardiovascular mortality) and all-cause mortality up to 30 days after surgery. Odds ratios (ORs) were calculated by multivariable logistic regression models. RESULTS: Crude incidence rates of MACE among patients with (n = 7137) and without (n = 474,046) prior stroke were 54.4 (95% CI, 49.1-59.9) vs 4.1 (95% CI, 3.9-4.2) per 1000 patients. Compared with patients without stroke, ORs for MACE were 14.23 (95% CI, 11.61-17.45) for stroke less than 3 months prior to surgery, 4.85 (95% CI, 3.32-7.08) for stroke 3 to less than 6 months prior, 3.04 (95% CI, 2.13-4.34) for stroke 6 to less than 12 months prior, and 2.47 (95% CI, 2.07-2.95) for stroke 12 months or more prior. MACE risks were at least as high for low-risk (OR, 9.96; 95% CI, 5.49-18.07 for stroke <3 months) and intermediate-risk (OR, 17.12; 95% CI, 13.68-21.42 for stroke <3 months) surgery compared with high-risk surgery (OR, 2.97; 95% CI, 0.98-9.01 for stroke <3 months) (P = .003 for interaction). Similar patterns were found for 30-day mortality: ORs were 3.07 (95% CI, 2.30-4.09) for stroke less than 3 months prior, 1.97 (95% CI, 1.22-3.19) for stroke 3 to less than 6 months prior, 1.45 (95% CI, 0.95-2.20) for stroke 6 to less than 12 months prior, and 1.46 (95% CI, 1.21-1.77) for stroke 12 months or more prior to surgery compared with patients without stroke. Cubic regression splines performed on the stroke subgroup supported that risk leveled off after 9 months. CONCLUSIONS AND RELEVANCE: A history of stroke was associated with adverse outcomes following surgery, in particular if time between stroke and surgery was less than 9 months. After 9 months, the associated risk appeared stable yet still increased compared with patients with no stroke. The time dependency of risk may warrant attention in future guidelines.

Cardiovascular and non-cardiovascular hospital admissions associated with atrial fibrillation: a Danish nationwide, retrospective cohort study.

OBJECTIVE: To examine the excess risk of hospitalisation in patients with incident atrial fibrillation (AF). DESIGN: A nationwide, retrospective cohort study. SETTING: Denmark. PARTICIPANTS: Data on all admissions in Denmark from 1997 to 2009 were collected from nationwide registries. After exclusion of subjects previously admitted for AF, data on 4 602 264 subjects and 10 779 945 hospital admissions contributed to the study. PRIMARY AND SECONDARY OUTCOME MEASURES: Age-stratified and sex-stratified admission rates were calculated for cardiovascular and non-cardiovascular admissions. Temporal patterns of readmission, relative risk and duration of frequent types of admission were calculated. RESULTS: Of 10 779 945 hospital admissions, 729 088(6.8%) were associated with AF. Admissions for cardiovascular reasons after 1, 3 and 6 months occurred for 6.0, 14.3 and 28.4% of AF patients versus 0.2, 0.6 and 1.8 of non-AF patients. Admissions for non-cardiovascular reasons after 1, 3 and 6 months comprised 6.8, 16.1 and 33.3% of AF patients and 1.2, 3.2 and 9.7% of non-AF patients. When stratified for age, AF was associated with similar cardiovascular admission rates across all age groups, while non-cardiovascular admission rates were higher in older patients. Within each age group and for both cardiovascular and non-cardiovascular admissions, AF was associated with higher rates of admission. When adjusted for age, sex and time period, patients with AF had a relative risk of 8.6 (95% CI 8.5 to 8.6) for admissions for cardiovascular reasons and 4.0 (95% CI 4.0 to 4.0) for admission for non-cardiovascular reasons. CONCLUSIONS: This study confirms that the burden of AF is considerable and driven by both cardiovascular and non-cardiovascular admissions. These findings underscore the importance of using clinical and pharmacological means to reduce the hospital burden of AF in Western healthcare systems.

Impact of dronedarone in atrial fibrillation and flutter on stroke reduction.

BACKGROUND: Dronedarone has been developed for treatment of atrial fibrillation (AF) or atrial flutter (AFL). It is an amiodarone analogue but noniodinized and without the same adverse effects as amiodarone. OBJECTIVE AND METHODS: This is a review of 7 studies (DAFNE, ADONIS, EURIDIS, ATHENA, ANDROMEDA, ERATO and DIONYSOS) on dronedarone focusing on efficacy, safety and prevention of stroke. There was a dose-finding study (DAFNE), 3 studies focusing on maintenance of sinus rhythm (ADONIS, EURIDIS and DIONYSOS), 1 study focusing on rate control (ERATO) and 2 studies investigating mortality and morbidity (ANDROMEDA and ATHENA). RESULTS: The target dose for dronedarone was established in the DAFNE study to be 400 mg twice daily. Both EURIDIS and ADONIS studies demonstrated that dronedarone was superior to placebo for maintaining sinus rhythm. However, DIONYSOS found that dronedarone is less efficient at maintaining sinus rhythm than amiodarone. ERATO concluded that dronedarone reduces ventricular rate in patients with chronic AF. The ANDROMEDA study in patients with severe heart failure was discontinued because of increased mortality in dronedarone group. Dronedarone reduced cardiovascular hospitalizations and mortality in patients with AF or AFL in the ATHENA trial. Secondly, according to a post hoc analysis a significant reduction in stroke was observed (annual rate 1.2% on dronedarone vs 1.8% on placebo, respectively [hazard ratio 0.66, confidence interval 0.46 to 0.96, P = 0.027]). In total, 54 cases of stroke occurred in 3439 patients (crude rate 1.6%) receiving dronedarone compared to 76 strokes in 3048 patients on placebo (crude rate 2.5%), respectively. CONCLUSION: Dronedarone can be used for maintenance of sinus rhythm and can reduce stroke in patients with AF who receive usual care, which includes antithrombotic therapy and heart rate control.

Efficacy and safety of dronedarone: a review of randomized trials.

IMPORTANCE OF THE FIELD: Dronedarone is developed for treatment of atrial fibrillation (AF) or flutter (AFL). It is a noniodinized amiodarone analogue and believed to be without the adverse effects of amiodarone. However, long-term adverse effects are not yet well investigated. AREAS COVERED IN THIS REVIEW: This is a review of seven studies on dronedarone. WHAT THE READER WILL GAIN: DAFNE established an effective dose to be 400 mg b.i.d. ADONIS and EURIDIS showed significant prevention of AF/AFL recurrence hazard ratio (HR 0.78 and 0.73) compared to placebo. In ATHENA, cardiovascular death/hospitalization was significantly reduced (HR 0.76) in patients with AF and additional risk factors. ANDROMEDA was stopped because dronedarone increased early mortality (HR 2.13) in advanced heart failure (HF). ERATO found that dronedarone significantly reduced heart rate compared to placebo in patients with AF. DIONYSOS showed that amiodarone was superior to dronedarone to maintain sinus rhythm in patients with AF/AFL. TAKE HOME MESSAGE: Dronedarone is superior to placebo but less efficient than amiodarone in maintaining sinus rhythm in patients with a history of AF. In patients with AF and risk factors dronedarone reduces cardiovascular mortality and morbidity, but in patients with severe HF dronedarone significantly increases mortality.