Choice of Oral Anticoagulant: Outcomes in Atrial Fibrillation Patients Post-Stroke Despite Direct Oral Anticoagulant Use.

Background: For patients with atrial fibrillation who have an ischemic stroke or transient ischemic attack (TIA) despite taking direct oral anticoagulants (DOACs), the optimal strategy for ongoing anticoagulation is unknown. Methods: Using provincial administrative databases in Alberta, Canada, we compared anticoagulant use before/after the breakthrough stroke/TIA and assessed recurrence of stroke/TIA or bleeding, with consideration of medication adherence. Adherence was defined as the proportion of days covered (PDC) being ≥ 80%. Results: Among 985 patients, the median age was 80 years (interquartile range 13), with a mean CHADS2 score of 1.7± 1 prior to the index event. Patients were followed for a median of 643 days (interquartile range 836). Following the index stroke/TIA event, 623 patients (63%) filled a prescription for the same DOAC regimen, 83 (8%) filled a prescription for a different dose, 155 (16%) switched DOAC agents, 51 (5%) switched to warfarin, and 73 (7%) filled no oral anticoagulant prescription. Patients who kept the same regimen more commonly had TIA index events (59%); patients who changed dose or drug more often had stroke index events (55%-78%). During follow-up, 135 (14%) had stroke/TIA recurrence, and 46 (5%) had bleeding; rates of each did not differ between prescribing patterns. Post-index event, the proportion of patients with a proportion of days covered ≥ 80% improved from 55% to 80%. Conclusions: Although most maintained the same DOAC regimen after stroke/TIA, rates of recurrent stroke/TIA and bleeding were similar across prescribing patterns. Stroke/TIA severity may have influenced prescribing practices. DOAC prescription adherence improved poststroke/TIA and signals an opportunity for optimization in patients with atrial fibrillation.

Contexte: Chez les patients atteints de fibrillation auriculaire qui subissent un accident vasculaire cérébral (AVC) ischémique ou un accident ischémique transitoire (AIT) malgré la prise d'anticoagulants oraux directe (AOD), la stratégie optimale pour la poursuite de l'anticoagulation est inconnue. Méthodologie: À partir des bases de données administratives provinciales en Alberta, au Canada, nous avons comparé l'utilisation d'anticoagulants avant/après l'AVC/AIT survenu pendant l'anticoagulothérapie et avons évalué la récurrence d'un AVC/AIT ou d'un saignement, en tenant compte de l'adhésion au traitement médicamenteux. L'adhésion a été définie comme une proportion de jours couverts (PJC) de 80 % ou plus. Résultats: Chez 985 patients, l'âge médian était de 80 ans (écart interquartile de 13) et le score CHADS2 moyen, de 1,7 ± 1 avant l'événement de référence. Les patients ont été suivis pendant une médiane de 643 jours (écart interquartile de 836). Après l'AVC/AIT de référence, 623 patients (63 %) ont fait exécuter une ordonnance du même schéma d'AOD, 83 (8 %) ont fait exécuter une ordonnance d'une dose différente, 155 (16 %) sont passés à d'autres AOD, 51 (5 %) sont passés à la warfarine et 73 (7 %) n'ont fait exécuter aucune ordonnance d'anticoagulant oral. Chez les patients qui ont continué à recevoir le même schéma, la plupart (59 %) avaient eu un AIT comme événement de référence; chez les patients qui ont changé de dose ou de médicament, la plupart (55 à 78 %) avaient eu un AVC comme événement de référence. Durant le suivi, 135 (14 %) ont connu un AVC/AIT récurrent et 46 (5 %) ont présenté un saignement; les taux de chaque manifestation ont été similaires pour les différents schémas de prescription. Après l'événement de référence, le pourcentage de patients ayant une PJC ≥ 80 % a augmenté, passant de 55 à 80 %. Conclusions: Malgré le maintien du même schéma d'AOD chez la plupart des patients après l'AVC/AIT, les taux d'AVC/AIT récurrent et de saignement ont été similaires avec tous les schémas de prescription. La gravité d'un AVC/AIT pourrait avoir influencé les pratiques de prescription. L'adhésion aux AOD prescrits s'est améliorée après un AVC/AIT et témoigne d'une possibilité d'optimisation chez les patients atteints de fibrillation auriculaire.

Pharmacists as Care Providers for Stroke Patients: A Systematic Review.

BACKGROUND: Pharmacists have become an integral member of the multidisciplinary team providing clinical patient care in various healthcare settings. Although evidence supporting their role in the care of patients with other disease states is well-established, minimal literature has been published evaluating pharmacist interventions in stroke patients. The purpose of this systematic review is to summarize the evidence evaluating the impact of pharmacist interventions on stroke patient outcomes. METHODS: Study abstracts and full-text articles evaluating the impact of a pharmacist intervention on outcomes in patients with an acute stroke/transient ischemic attack (TIA) or a history of an acute stroke/TIA were identified and a qualitative analysis performed. RESULTS: A total of 20 abstracts and full-text studies were included. The included studies provided evidence supporting pharmacist interventions in multiple settings, including emergency departments, inpatient, outpatient, and community pharmacy settings. In a significant proportion of the studies, pharmacist care was collaborative with other healthcare professionals. Some of the pharmacist interventions included participation in a stroke response team, assessment for thrombolytic use, medication reconciliation, participation in patient rounds, identification and resolution of drug therapy problems, risk-factor reduction, and patient education. Pharmacist involvement was associated with increased use of evidence-based therapies, medication adherence, risk-factor target achievement, and maintenance of health-related quality of life. CONCLUSIONS: Available evidence suggests that a variety of pharmacist interventions can have a positive impact on stroke patient outcomes. Pharmacists should be considered an integral member of the stroke patient care team.

Critical international normalized ratio results after hours: To call or not to call?

OBJECTIVE: To determine whether the timing of notification of critical international normalized ratio (INR) results (during or after clinic hours) altered the clinician's ability to affect same-day patient care. DESIGN: Retrospective chart review. SETTING: The Anticoagulation Management Service at the University of Alberta Hospital in Edmonton. PARTICIPANTS: A total of 276 patients with critical INR results (> 5.0) separated by at least 30 days were identified to have 200 critical INR results reported during clinic hours and 200 reported after hours. MAIN OUTCOME MEASURES: Differences in the proportion of patients with critical INR results having same-day care altered (by changing warfarin dose, administering vitamin K, or referring for assessment) between those with results reported during clinic hours compared with those with results reported after clinic hours. Differences by highly critical INR results (> 9.0 vs ≤ 9.0) and whether patients experienced thromboembolism or bleeding within 30 days were also assessed. RESULTS: Same-day patient care was affected for 174 out of 200 (87.0%) critical INR results reported during clinic hours compared with 101 out of 200 (50.5%) reported after clinic hours (P < .001). The most common reason for not being able to intervene was that warfarin had already been taken. Warfarin dose alteration was the most frequent change (97.1% during clinic hours and 96.0% after hours). When patients with INRs greater than 9.0 were assessed separately, the ability to affect care increased for INRs reported both during and after clinic hours (92.9% and 63.6%, respectively), largely attributable to oral vitamin K use. Overall, thromboembolic and major bleeding event rates were low and were similar in both groups. CONCLUSION: Same-day care was less likely to be affected by critical INR results communicated after hours, most commonly because the patient had already taken their daily warfarin dose. However, after-hours care was still affected for 1 out of 2 patients, which is meaningful and supports current practice.

Use of low-molecular-weight heparin to bridge therapy in obese patients and in patients with renal dysfunction.

OBJECTIVE: To recommend strategies to bridge therapy with low-molecular-weight heparin (LMWH) in obese patients and in patients with renal dysfunction. METHODS: A MEDLINE search was performed of the literature from January 1966-November 2005. Published material dealing with bridging of anticoagulation therapy or short-term use of LMWH therapy in patients with renal dysfunction or obesity was reviewed. The manufacturers of enoxaparin, dalteparin, and tinzaparin were contacted for the references used to determine dosing recommendations. RESULTS: Although LMWH has been commonly used to bridge therapy, our search revealed no trials that specifically examined LMWH bridge therapy in obese patients or in patients with renal dysfunction. However, nine trials using LMWH in obese patients and 14 trials using LMWH in patients with renal dysfunction were identified. When compared with normal-weight individuals, obese patients receiving enoxaparin and dalteparin based on total body weight did not demonstrate higher hemorrhage rates or antifactor Xa levels. Subtherapeutic antifactor Xa levels were more common with once-daily dosing of enoxaparin than with dosing every 12 hours. Enoxaparin accumulates in patients with a creatinine clearance of 30 ml/minute or less; in this population, enoxaparin dosage adjustments have been attempted. Tinzaparin does not accumulate in patients with a creatinine clearance of 20 ml/minute or greater after at least 10 days of dosing. CONCLUSION: Obese patients, weighing 90-150 kg, receiving LMWH for bridge therapy should receive dosages based on total body weight. Unfractionated heparin is recommended in patients weighing more than 150 kg; however, if LMWH is used, antifactor Xa levels should be monitored. Bridging with enoxaparin should be limited to patients with a creatinine clearance greater than 30 ml/minute. The use of enoxaparin 1 mg/kg once/day for patients with a creatinine clearance of 30 ml/minute or less is not recommended for anticoagulation bridge therapy. Tinzaparin may be considered for cross-coverage of high-risk patients with recent or recurrent venous thromboembolism who have a creatinine clearance of at least 20 ml/minute.