Time trends and patient selection in the use of continuous electrocardiography for detecting atrial fibrillation after stroke: a nationwide cohort study.

BACKGROUND AND PURPOSE: Clinical use of continuous electrocardiography (cECG) for detecting atrial fibrillation (AF) after stroke is unclear. In a Danish nationwide cohort, we described post-stroke time trends in outpatient cECG usage and AF incidence and characterized factors associated with cECG use. METHODS: Patients without AF discharged after their first ischaemic stroke between 2010 and 2016 were identified from Danish nationwide registries. cECG included Holter or event recording within 120 days from discharge. Cumulative incidence analysis and multivariable adjusted logistic regression were used to assess time trends and factors associated with cECG usage and AF. RESULTS: The study population comprised 39 641 patients. Cumulative use of cECG increased threefold from 3.3% [95% confidence intervals (CI), 2.8-3.8] in 2010 to 10.5% (95% CI, 9.7-11.3) in 2016. Correspondingly, cumulative incidence of post-stroke AF increased from 1.9% (95% CI, 1.5-2.3) to 2.8% (95% CI, 2.4-3.2). Of all cECG-evaluated patients, 6.3% received an AF diagnosis versus 2.2% of the unevaluated. Receiving cECG was associated with increased odds of AF (odds ratio, 3.4; 95% CI, 2.8-4.0). Lower age, milder strokes and less comorbidity were associated with increased odds of receiving cECG. In contrast, risk factors for AF were increasing age and more comorbidity. CONCLUSIONS: Post-stroke outpatient cECG use and AF incidence have increased over time, but screening rates were low. cECG use was associated with tripled odds of detecting AF. There was a disparity between factors associated with cECG use and risk factors of AF. This raise questions as to the appropriateness of the current clinical approach to post-stoke AF detection.

Comparative thromboembolic risk in atrial fibrillation with and without a secondary precipitant-Danish nationwide cohort study.

OBJECTIVES: We compared long-term outcomes in patients with atrial fibrillation (AF) with and without a secondary precipitant. DESIGN AND SETTING: Retrospective cohort study based on Danish nationwide registries. PARTICIPANTS: Patients with AF with and without secondary precipitants (1996-2015) were matched 1:1 according to age, sex, calendar year, CHA2DS2-VASc score and oral anticoagulation therapy (OAC), resulting in a cohort of 39 723 patients with AF with a secondary precipitant and the same number of patients with AF without a secondary precipitant. Secondary precipitants included alcohol intoxication, thyrotoxicosis, myocardial infarction, surgery and infection in conjunction with AF. PRIMARY AND SECONDARY OUTCOMES: The primary outcome in this study was thromboembolic events. Secondary outcomes included AF rehospitalisation and death. Long-term risks of outcomes were examined by multivariable Cox regression analysis. RESULTS: The most common precipitants were infection (55.0%), surgery (13.2%) and myocardial infarction (12.0%). The 5-year absolute risk of thromboembolic events (taking death into account as a competing risk) in patients with AF grouped according to secondary precipitants were 8.3% (alcohol intoxication), 8.5% (thyrotoxicosis), 12.1% (myocardial infarction), 11.6% (surgery), 12.2% (infection), 10.1% (>1 precipitant) and 12.3% (no secondary precipitant). In the multivariable analyses, AF with a secondary precipitant was associated with the same or an even higher thromboembolic risk than AF without a secondary precipitant. One exception was patients with AF and thyrotoxicosis: those not initiated on OAC therapy carried a lower thromboembolic risk the first year of follow-up than matched patients with AF without a secondary precipitant and no OAC therapy. CONCLUSIONS: In general, AF with a secondary precipitant was associated with the same thromboembolic risk as AF without a secondary precipitant. Consequently, this study highlights the need for more research regarding the long-term management of patients with AF associated with a secondary precipitant.

Initiation of anticoagulation in atrial fibrillation: which factors are associated with choice of anticoagulant?

BACKGROUND: The use of non-vitamin K antagonist oral anticoagulants (NOACs) for stroke prophylaxis in atrial fibrillation (AF) is increasing rapidly. We compared characteristics of AF patients initiated on NOACs versus vitamin K antagonists (VKAs). METHODS: Using Danish nationwide registry data, we identified AF patients initiating either a VKA or a NOAC from 22 August 2011 until 30 September 2016. We compared patient characteristics including age, gender, comorbidities, concomitant pharmacotherapy and CHA2 DS2 -VASc and HAS-BLED scores in patients initiated on a VKA, dabigatran, rivaroxaban or apixaban. Differences were examined using multivariable logistic regression models. RESULTS: The study population comprised 51 981 AF patients of whom 19 989 (38.5%) were initiated on a VKA, 13 242 (25.5%) on dabigatran, 8475 (16.3%) on rivaroxaban and 10 275 (19.8%) on apixaban. Those patients initiated on apixaban had higher mean ± SD CHA2 DS2 -VASc scores than those initiated on a VKA (3.1 ± 1.6 vs. 2.9 ± 1.6). Those initiated on dabigatran had lower mean CHA2 DS2 -VASc scores (2.7 ± 1.6) than all other groups. Patients with a history of a prior stroke were significantly more likely to be initiated on a NOAC compared with a VKA [odds ratio (OR) 1.35, 95% confidence interval (CI) 1.28-1.43]. By contrast, patients with a history of myocardial infarction were less likely to be initiated on a NOAC compared with a VKA (OR 0.72, 95% CI 0.67-0.77). CONCLUSIONS: Atrial fibrillation patients who were initiated on apixaban had higher stroke risk scores than patients initiated on VKAs. Interestingly, opposite results were found for dabigatran.