Prognosis and antithrombotic practice patterns in patients with recurrent and transient atrial fibrillation following acute coronary syndrome: A nationwide study.

BACKGROUND: First-time detected atrial fibrillation (AF) is associated with aggravated prognosis in patients admitted with acute coronary syndrome (ACS). Yet, among patients surviving beyond one year after ACS, it remains unclear how the recurrence of AF within the initial year after ACS affects the risk of stroke. METHODS: With Danish nationwide data from 2000 to 2021, we identified all patients with first-time ACS who were alive one year after discharge (index date). Patients were categorized into: i) no AF; ii) first-time detected AF during ACS admission without a recurrent hospital contact with AF (transient AF); and iii) first-time detected AF during ACS admission with a subsequent recurrent hospital contact with AF (recurrent AF). From index date, two-year rates of ischemic stroke were compared using multivariable adjusted Cox regression analysis. Treatment with antithrombotic therapy was assessed as filled prescriptions between 12 and 15 months following ACS discharge. RESULTS: We included 139,137 patients surviving one year post ACS discharge: 132,944 (95.6%) without AF, 3920 (2.8%) with transient AF, and 2273 (1.6%) with recurrent AF. Compared to those without AF, the adjusted two-year hazard ratios of ischemic stroke were 1.45 (95% CI, 1.22-1.71) for patients with transient AF and 1.47 (95% CI: 1.17-1.85) for patients with recurrent AF. Prescription rates of oral anticoagulation increased over calendar time, reaching 68.3% and 78.7% for transient and recurrent AF, respectively, from 2019 to 2021. CONCLUSION: In patients surviving one year after ACS with first-time detected AF, recurrent and transient AF were associated with a similarly increased long-term rate of ischemic stroke.

Perioperative Atrial Fibrillation and One-year Clinical Outcomes in Patients Following Major Emergency Abdominal Surgery.

The prevalence and impact of perioperative atrial fibrillation (AF) during an admission for major emergency abdominal surgery are sparsely examined. Therefore, this study aimed to compare the 30-day and 1-year outcomes (AF-related hospitalization, stroke, and all-cause mortality) in patients with and without perioperative AF to their major emergency abdominal surgery. All patients without a history of AF who underwent major emergency abdominal surgery from 2000 to 2019 and discharged alive were identified using Danish nationwide registries. Patients with and without perioperative AF (defined as new-onset AF during the index hospitalization) were matched 1:4 on age, gender, year of surgery, and type of surgery. The cumulative incidences and hazard ratios of outcomes were assessed using a multivariable Cox regression analysis comparing patients with and without perioperative AF. A total of 2% of patients were diagnosed with perioperative AF. The matched cohort comprised 792 and 3,168 patients with and without perioperative AF, respectively (median age 78 years [twenty-fifth to seventy-fifth percentile 70 to 83 years]; 43% men). Cumulative incidences of AF-related hospitalizations, stroke, and mortality 1 year after discharge were 30% versus 3.4%, 3.4% versus 2.7%, and 35% versus 22% in patients with and without perioperative AF, respectively. The 30-day outcomes were similarly elevated among patients with perioperative AF. Perioperative AF during an admission for major emergency abdominal surgery was associated with higher 30-day and 1-year rates of AF-related hospitalization and mortality and similar rates of stroke. These findings suggest that perioperative AF is a prognostic marker of increased morbidity and mortality in relation to major emergency abdominal surgery and warrants further investigation.

Long-Term Incidence of Ischemic Stroke After Transient Ischemic Attack: A Nationwide Study From 2014 to 2020.

BACKGROUND: The short-term incidence of ischemic stroke after a transient ischemic attack (TIA) is high. However, data on the long-term incidence are not well known but are needed to guide preventive strategies. METHODS: Patients with first-time TIA (index date) in the Danish Stroke Registry (January 2014-December 2020) were included and matched 1:4 with individuals from the background population and 1:1 with patients with a first-time ischemic stroke on the basis of age, sex, and calendar year. The incidences of ischemic stroke and mortality from index date were estimated by Aalen-Johansen and Kaplan-Meier estimators, respectively, and compared between groups using multivariable Cox regression. RESULTS: We included 21 500 patients with TIA, 86 000 patients from the background population, and 21 500 patients with ischemic stroke (median age, 70.8 years [25th-75th percentile, 60.8-78.7]; 53.1% males). Patients with TIA had more comorbidities than the background population, yet less than the control stroke population. The 5-year incidence of ischemic stroke after TIA (6.1% [95% CI, 5.7-6.5]) was higher than the background population (1.5% [95% CI, 1.4-1.6], P<0.01; hazard ratio, 5.14 [95% CI, 4.65-5.69]) but lower than the control stroke population (8.9% [95% CI, 8.4-9.4], P<0.01; hazard ratio, 0.58 [95% CI, 0.53-0.64]). The 5-year mortality for patients with TIA (18.6% [95% CI, 17.9-19.3]) was higher than the background population (14.8% [95% CI, 14.5-15.1], P<0.01; hazard ratio, 1.26 [95% CI, 1.20-1.32]) but lower than the control stroke population (30.1% [95% CI, 29.3-30.9], P<0.01; hazard ratio, 0.41 [95% CI, 0.39-0.44]). CONCLUSIONS: Patients with first-time TIA had an ischemic stroke incidence of 6.1% during the 5-year follow-up period. After adjustment for relevant comorbidities, this incidence was approximately 5-fold higher than what was found for controls in the background population and 40% lower than for patients with recurrent ischemic stroke.

Temporal changes in incidence, treatment strategies and 1-year re-admission rates in patients with atrial fibrillation/flutter under 65 years of age: A Danish nationwide study.

AIM: To examine temporal changes in incidence rates of atrial fibrillation/flutter (AF), treatment strategies, and AF readmission rates in patients <65 years. METHODS: Using Danish nationwide registries, we identified patients <65 years with a first-time AF diagnosis from 2000 to 2018. The cohort was categorized according to calendar periods; 2000-2002, 2003-2006, 2007-2010, 2011-2014, and 2015-2018. In this retrospective cohort study the incidence rate (IR) of AF per 100,000 person years (PY), catheter ablation, electrical cardioversion, use of pharmacotherapy, and AF readmission, were investigated in the first year following AF diagnosis. RESULTS: We identified 60,917 patients; 8150 (13.4%) in 2000-2002, 11,898 (19.5%) in 2003-2006, 13,560 (22.3%) in 2007-2010, 14,167 (23.3%) in 2011-2014, and 13,142 (21.6%) in 2015-2018. Apart from 2015 to 2018, a stepwise increase in the crude IR of AF was observed across calendar periods; 2000-2002: 78.7 (95% CI 77.0;80.4), 2003-2006: 86.3 (84.7;87.8), 2007-2010: 97.9 (96.3;99.6), 2011-2014: 102.3 (100.7;104.0), 2015-2018: 93.6 (92.0;95.2). Over the studied time-periods, we found a stepwise increase in the cumulative incidence of catheter ablation (1.2% to 7.6%) electrical cardioversion (2.0% to 8.7%) and treatment with oral anticoagulant therapy (OAC) (28.5% to 47.8%) within the first year of diagnosis. No temporal differences in incidence of 1-year AF readmission were identified (AF-readmissions: 2000-2002: 32.7%, 2003-2006: 31.1%, 2007-2010: 32.2%, 2011-2014: 32.1% and 2015-2018: 31.7%). CONCLUSION: The incidence rate of AF in patients <65 years increased from 2000 to 2018, as did the use of catheter ablation, electrical cardioversion and OAC in the first year following AF diagnosis. 1-year AF readmission incidence remained stable around 32% over the study period.

Incidence of thyroid dysfunction following initiation of amiodarone treatment in patients with and without heart failure: a nationwide cohort study.

AIMS: Thyroid dysfunction is considered the most frequent complication to amiodarone treatment, but data on its occurrence outside clinical trials are sparse. The present study aimed to examine the incidence of thyroid dysfunction following initiation of amiodarone treatment in a nationwide cohort of patients with and without heart failure (HF). METHODS AND RESULTS: In Danish registries, we identified all patients with first-time amiodarone treatment during the period 2000-18, without prior thyroid disease or medication. The primary outcome was a composite of thyroid diagnoses and initiation of thyroid drugs. Outcomes were assessed at 1-year follow-up, and for patients free of events in the first year, in a landmark analysis for the subsequent 5 years. We included 43 724 patients with first-time amiodarone treatment, of whom 16 939 (38%) had HF. At 1-year follow-up, the cumulative incidence and adjusted hazard ratio (HR) of the primary outcome were 5.3% and 1.37 (95% confidence interval 1.25-1.50) in patients with a history of HF and 4.2% in those without HF (reference). In the 1-year landmark analysis, the subsequent 5-year cumulative incidences and adjusted HRs of the primary outcome were 5.3% (reference) in patients with 1-year accumulated dose <27.38 g [corresponding to average daily dose (ADD <75 mg)], 14.0% and HR 2.74 (2.46-3.05) for 27.38-45.63 g (ADD 75-125 mg), 20.0% and HR 4.16 (3.77-4.59) for 45.64-63.88 g (ADD 126-175 mg), and 24.5% and HR 5.30 (4.82-5.90) for >63.88 g (ADD >175 mg). CONCLUSION: Among patients who initiated amiodarone treatment, around 5% had thyroid dysfunction at 1-year follow-up, with a slightly higher incidence in those with HF. A dose-response relationship was observed between the 1-year accumulated amiodarone dose and the subsequent 5-year cumulative incidence of thyroid dysfunction.

Use of torsades de pointes risk drugs among patients with out-of-hospital cardiac arrest and likelihood of shockable rhythm and return of spontaneous circulation: A nationwide study.

AIM: Treatment with certain drugs can augment the risk of developing malignant arrhythmias (e.g. torsades de pointes [TdP]). Hence, we examined the overall TdP risk drug use before out-of-hospital cardiac arrest (OHCA) and possible association with shockable rhythm and return of spontaneous circulation (ROSC). METHODS: Patients ≥18 years with an OHCA of cardiac origin from the Danish Cardiac Arrest Registry (2001-2014) and TdP risk drug use according to www.CredibleMeds.org were identified. Factors associated with TdP risk drug use and secondly how use may affect shockable rhythm and ROSC were determined by multivariable logistic regression. RESULTS: We identified 27,481 patients with an OHCA of cardiac origin (median age: 72 years [interquartile range 62.0, 80.0 years]). A total of 37% were in treatment with TdP risk drugs 0-30 days before OHCA compared with 33% 61-90 days before OHCA (p < 0.001). Most commonly used TdP risk drugs were citalopram (36.1%) and roxithromycin (10.7%). Patients in TdP risk drug treatment were older (75 vs 70 years) and more comorbid compared with those not in treatment. Subsequently, TdP risk drug use was associated with less likelihood of the presenting rhythm being shockable (odds ratio [OR] = 0.63, 95% confidence interval [CI]:0.58-0.69) and ROSC (OR = 0.73, 95% CI:0.66-0.80). CONCLUSION: TdP risk drug use increased in the time leading up to OHCA and was associated with reduced likelihood of presenting with a shockable rhythm and ROSC in an all-comer OHCA setting. However, patients in TdP risk drug treatment were older and more comorbid than patients not in treatment.

Incidence of ischaemic stroke and mortality in patients with acute coronary syndrome and first-time detected atrial fibrillation: a nationwide study.

AIMS: The aim of this study was to examine contemporary data on the 1-year prognosis of patients surviving acute coronary syndrome (ACS) and concomitant first-time detected atrial fibrillation (AF). METHODS AND RESULTS: Using Danish nationwide registries, we identified all patients surviving a first-time admission with ACS from 2000 to 2018 and grouped them into (i) those without AF prior to or during ACS; (ii) those with a history of AF; and (iii) those with first-time detected AF during admission with ACS. With 1 year of follow-up, rates of ischaemic stroke, death, and bleeding were compared between study groups using multivariable adjusted Cox proportional hazards analysis. We included 161 266 ACS survivors: 135 878 (84.2%) without AF, 18 961 (11.8%) with history of AF, and 6427 (4.0%) with first-time detected AF at admission with ACS. Compared to those without AF, the adjusted 1-year rates of outcomes were as follows: ischaemic stroke [hazard ratio (HR) 1.38 (95% CI 1.22-1.56) for patients with history of AF and HR 1.67 (95% CI 1.38-2.01) for patients with first-time detected AF]; mortality [HR 1.25 (95% CI 1.21-1.31) for patients with history of AF and HR 1.52 (95% CI 1.43-1.62) for patients with first-time detected AF]; and bleeding [HR 1.22 (95% CI 1.14-1.30) for patients with history of AF and HR 1.28 (95% CI 1.15-1.43) for patients with first-time detected AF]. CONCLUSION: In patients with ACS, first-time detected AF appeared to be at least as strongly associated with the 1-year rates of ischaemic stroke, mortality, and bleeding as compared with patients with a history of AF.

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.

Time to Thrombolysis and Long-Term Outcomes in Patients With Acute Ischemic Stroke: A Nationwide Study.

Background and Purpose: It is well-established that increasing treatment delay reduces the benefits of thrombolysis in patients with acute ischemic stroke. However, most studies focus on short-term outcomes. This study examined long-term outcomes according to time to thrombolysis in patients with first-time ischemic stroke. Methods: In this nationwide cohort study, all Danish patients with first-time ischemic stroke treated with intravenous thrombolysis between 2011 and 2017 and alive at discharge were identified through the Danish Stroke Registry. The association between time from symptom onset to thrombolysis and the long-term rate of the composite of death and recurrent ischemic stroke was examined using multivariable Cox regression and restricted cubic spline analysis. Results: The study population included 6252 patients with first-time ischemic stroke treated with thrombolysis (median age, 69 years [25th­75th percentile 60­78 years], 60% men). The median follow-up was 2.5 years (25th­75th percentile 1.2­4.1 years). The median time to thrombolysis was 138 minutes (25th­75th percentile 101­185 minutes), and the median National Institutes of Health Stroke Scale score at presentation was 5 (25th­75th percentile 3­10). The absolute 3-year risk of the composite outcome was 19.0% (95% CI, 16.4%­21.8%) in the 0 to 90 minute group, 23.3% (21.8%­24.9%) in the 91 to 180 minute group, and 23.8% (21.6%­26.1%) in the 181 to 270 minute group. Compared with thrombolysis within 90 minutes, time to thrombolysis >90 minutes was associated with a higher rate of the composite outcome (91­180 minute: adjusted hazard ratio, 1.25 [95% CI, 1.06­1.48]; 181­270 minutes: adjusted hazard ratio, 1.35 [95% CI, 1.12­1.61]). In restricted cubic spline analysis, the rate of the composite outcome increased with increasing time to thrombolysis and leveled off after 138 minutes. Conclusions: In this nationwide cohort of patients with ischemic stroke, the long-term rate of the composite of death and recurrent ischemic stroke increased with increasing time from symptom onset to initiation of thrombolysis.

Switching from vitamin K antagonist to dabigatran in atrial fibrillation: differences according to dose.

AIMS: In atrial fibrillation (AF) patients 150 mg b.i.d. dabigatran is the standard dose, yet guidelines recommend 110 mg b.i.d. when bleeding risk is high. It is unknown to which extend these recommendations are followed in patients switching from vitamin K antagonist (VKA) to dabigatran. The aim of this study was to investigate if AF patients are switched from VKA to the appropriate dose of dabigatran. METHODS AND RESULTS: Using nationwide registries (22 August 2011 to 31 December 2012), we identified VKA-experienced AF patients with available creatinine values who switched to dabigatran. European guidelines criteria 2012 on dabigatran dosing were examined: age ≥80 years, HAS-BLED ≥3, estimated glomerular filtration rate (eGFR)<50 mL/min/1.73 m2, or use of interacting drugs. We identified 1626 VKA-experienced AF patients who switched to dabigatran 110 mg (820 patients) or 150 mg (806 patients). Patients who switched to 110 mg compared with 150 mg were older [median age 82 years (Q1-Q3: 77-86) vs. 68 years (Q1-Q3: 64-74)], more often females (54% vs. 35%), had a higher comorbidity burden, higher proportion with CHA2DS2-VASc score ≥2 (98% vs. 80%), and more with a HAS-BLED score ≥3 (46% vs. 28%). Patients switched to 110 mg had a higher absolute risk of mortality compared with patients switched to 150 mg. Overall, 26% were inappropriately dosed and 14% were switched to 110 mg although the higher dose was indicated. Furthermore, 39% of patients switched to 150 mg fulfilled one or more criteria for 110 mg, this mostly driven by high HAS-BLED scores (28.2% of patients on 150 mg). Female sex, age ≥80 years, eGFR < 50 mL/min/1.73 m2, drugs interacting with dabigatran, and prior bleeding were associated with switch to 110 mg. Patients inappropriately dosed had similar risk of mortality as patients appropriately dosed. CONCLUSION: Among VKA-experienced AF patients one in four were switched to a dabigatran dose contrary to guideline recommendations.

Time trends in incidence, comorbidity, and mortality of ischemic stroke in Denmark (1996-2016).

OBJECTIVE: To examine whether the incidence, comorbidity, and mortality of first-time ischemic stroke changed in Denmark between 1996 and 2016 overall and according to age and sex using a nationwide cohort design. METHODS: In this cohort study, 224,617 individuals ≥18 years of age admitted with first-time ischemic stroke between 1996 and 2016 were identified through Danish nationwide registries. We calculated annual age-standardized incidence rates and absolute 30-day and 1-year mortality risks. Furthermore, we calculated annual incidence rate ratios using Poisson regression, odds ratios for 30-day mortality using logistic regression, and hazard ratios for 1-year mortality using Cox regression. RESULTS: The overall age-standardized incidence rates of ischemic stroke per 1,000 person-years increased from 1996 (2.70 [95% confidence interval [CI] 2.65-2.76]) to 2002 (3.25 [95% CI 3.20-3.31]) and then gradually decreased to below the initial level until 2016 (1.99 [95% CI 1.95-2.02]). Men had higher incidence rates than women in all age groups except 18 to 34 and ≥85 years. Absolute mortality risk decreased between 1996 and 2016 (30-day mortality from 17.1% to 7.6% and 1-year mortality from 30.9% to 17.3%). Women between 55 and 64 and ≥85 years of age had higher mortality than men. Similar trends were observed for all analyses after multivariable adjustment. The prevalence of atrial fibrillation, hypertension, diabetes mellitus, and use of lipid-lowering medication increased during the study period. CONCLUSIONS: The age-standardized incidence of first-time hospitalization for ischemic stroke increased from 1996 to 2002 and then gradually decreased to below the initial level until 2016. Absolute 30-day and 1-year mortality risks decreased between 1996 and 2016. These findings correspond to increased stroke prevention awareness and introduction of new treatments during the study period.

C-reactive protein after coronary artery bypass graft surgery and its relationship with postoperative atrial fibrillation.

AIMS: Postoperative atrial fibrillation (POAF), a common complication following coronary artery bypass graft (CABG) surgery, is associated with increased morbidity and mortality. Inflammation may be an important factor for the pathogenesis of POAF, and increased preoperative levels of C-reactive protein (CRP) are associated with the development of POAF. However, the relationship between postoperative CRP and POAF is less well established. METHODS AND RESULTS: Patients undergoing first-time isolated CABG surgery (1 January 2000-31 December 2016) were identified using the Eastern Danish Heart Surgery Database and nationwide administrative registries. Patients with no history of atrial fibrillation and with available CRP measurements from postoperative day (POD) 4 were included. The study population was divided into quartiles based on CRP. The association between CRP levels and the odds of developing POAF was investigated using multivariable logistic regression analysis. We included 6711 patients. The CRP intervals on POD 4 for the CRP groups (lowest to highest) were ≤90, >90 to ≤127, >127 to ≤175, and >175 mg/L, respectively. Patients in the highest CRP group were older and more often men compared with patients in the lowest CRP group [median age 67 years (P25-P75: 61-73) and 84.7% men vs. median age 64 years (P25-P75: 56-70) and 77.9% men]. In the lowest and highest CRP groups, 25% and 35% developed POAF, respectively. In adjusted analysis, the highest CRP group, compared with the lowest CRP group, was associated with greater odds of developing POAF (odds ratio 1.31; 95% confidence interval 1.12-1.54). CONCLUSION: Increased postoperative CRP levels after CABG surgery was associated with the development of POAF.

The importance of time in therapeutic range in switching from vitamin K antagonist to non-vitamin K antagonist oral anticoagulants in atrial fibrillation.

AIMS: Patients with non-valvular atrial fibrillation (NVAF) receiving vitamin K antagonists (VKAs) with time in therapeutic international normalized ratio (INR) range (TTR) <70%, despite good adherence, are by guidelines recommended to switch to non-VKA oral anticoagulants (NOACs). The aim was to assess if patients are switched from VKA to NOAC when TTR is <70% in a real-world setting. METHODS AND RESULTS: Non-valvular atrial fibrillation patients receiving VKA (1 January 2010 to 31 December 2012) were identified in nationwide registries. Time in therapeutic range was calculated by the Rosendaal method by a minimum of three INR values. Time in therapeutic range of patients continuing VKA (non-switchers) were compared with patients switched from VKA to dabigatran or rivaroxaban (switchers), the only NOACs available at that time. Factors associated with switching were analysed in a multivariable logistic regression model. 7276 patients with NVAF receiving VKA were included; of these, 6437 (88.5%) patients continued VKA [57.9% male, median age 76.7 years (Q1-Q3 68.9-83.5)] and 839 (11.5%) switched to NOAC [54.0% male, median age 76.5 years (Q1-Q3 68.4-83.6)]. No significant differences in CHA2DS2-VASc and HAS-BLED scores were seen between the groups. The mean TTR for non-switchers was 64.0 [standard deviation (SD) 27.8] and 52.9 (SD 28.1) for switchers. Among non-switchers, 51% had a TTR <70% vs. 69% among switchers. 85% of patients with TTR <70%, were not switched contrary to recommendations. Time in therapeutic range <70% was associated with the switch [odds ratio 2.28, 95% confidence interval (1.92-2.72)]. CONCLUSION: A TTR below 70% was associated with switching from VKA to NOAC, yet by guidelines, most patients were still not switched.

Outcomes Among Patients With Atrial Fibrillation and Appropriate Anticoagulation Control.

BACKGROUND: Atrial fibrillation (AF) patients on a vitamin K antagonist (VKA) with time in therapeutic range (TTR) ≥70% are not recommended to switch to a direct oral anticoagulant according to guidelines. OBJECTIVES: This study sought to assess future TTR and risk of stroke/thromboembolism and major bleeding among AF patients on VKA with TTR ≥70%. METHODS: The authors used Danish nationwide registries to identify AF patients on VKA from 1997 to 2011 with available international normalized ratio values. Patients were included 6 months after VKA initiation, divided according to TTR, and followed for 12 months after inclusion. Cox proportional hazard models estimated hazard ratios (HRs). TTR was examined both as a baseline variable and as a time-dependent covariate in the Cox models. RESULTS: Of the 4,772 included AF patients still on VKA 6 months after initiation, 1,691 (35.4%) had a TTR ≥70%, and 3,081 (65.6%) had a TTR <70%. Among patients with prior TTR ≥70% still on treatment 12 months after inclusion, only 513 (55.7%) still had a TTR ≥70%. Compared with prior TTR ≥70%, prior TTR <70% was not associated with a higher risk of stroke/thromboembolism (HR: 1.14; 95% confidence interval [CI]: 0.77 to 1.70) or major bleeding (HR: 1.12; 95% CI: 0.84 to 1.49). When the authors estimated TTR time-dependently during follow-up, TTR <70% was associated with an increased risk of stroke/thromboembolism (HR: 1.91; 95% CI: 1.30 to 2.82) and major bleeding (HR: 1.34; 95% CI: 1.02 to 1.76). CONCLUSIONS: Among AF patients on VKA, almost one-half of patients with prior TTR ≥70% had TTR <70% during the following year. Prior TTR ≥70% per se had limited long-term prognostic value.

Shifting to a non-vitamin K antagonist oral anticoagulation agent from vitamin K antagonist in atrial fibrillation.

Aims: After non-vitamin K antagonist (VKA) oral anticoagulation agents (NOAC) have been approved for thrombo-embolic prophylaxis in non-valvular atrial fibrillation (NVAF), utilization of oral anticoagulants (OAC) in NVAF has changed. Contemporary shifting from a VKA to a NOAC (dabigatran, rivaroxaban, or apixaban) has not been quantified, and could help assess whether these drugs are used according to recommendations. Methods and results: Using Danish nationwide registries, we identified all VKA-experienced NVAF patients initiating a NOAC from 22 August 2011 to 31 December 2015 (shifters) and all VKA-experienced NVAF patients who were not switched to NOACs (non-shifters). Baseline characteristics and temporal utilization trends were examined. We included 62 065 patients with NVAF; of these, 19 386 (29.6%) shifted from a VKA to a NOAC (9973 (54.2%) shifted to dabigatran, 4775 (26.0%) to rivaroxaban, and 3638 (19.8%) to apixaban). Shifting was associated with lower age [odds ratio (OR) 0.95, 95% confidence interval (95% CI) 0.94-0.96 per 5 year increments], female gender (OR 1.33, 95% CI 1.28-1.38), and certain co-morbidities: more often stroke, bleeding, heart failure, and alcohol abuse, and less often hypertension, ischaemic heart disease, and diabetes. Shifting was common and initially dominated by shifting from VKA to dabigatran, but at the end of 2015, most shifters were shifted to rivaroxaban (45%) or apixaban (45%) whereas shifting to dabigatran decreased (to 10%). Conclusion: In a contemporary setting among VKA-experienced NVAF patients; VKA is still prevalent although about 30% by December 2015 had shifted to a NOAC.