Effects of anticoagulation provider continuity on time in therapeutic range for warfarin patients

Qualidade da Anticoagulação Oral em Pacientes com Fibrilação Atrial em um Hospital Terciário no Brasil

Fundamento

A fibrilação atrial (FA) afeta de 0,5% a 2,0% da população geral e geralmente está associada a doenças estruturais cardíacas, comprometimento hemodinâmico e complicações tromboembólicas. A anticoagulação oral previne eventos tromboembólicos e é monitorada pela razão normalizada internacional (RNI).

Objetivos

Avaliar a estabilidade do RNI em pacientes com FA não valvar tratados com anticoagulante varfarina, avaliar complicações tromboembólicas ou hemorrágicas e identificar o grupo com risco mais alto de eventos tromboembólicos ou hemorrágicos.

Métodos

Dados de prontuários médicos de 203 pacientes atendidos em um hospital terciário no Brasil foram analisados e o tempo de intervalo terapêutico (TTR) foi calculado usando-se o método Rosendaal. Em seguida possíveis fatores que influenciam o TTR foram analisados e a relação entre TTR e eventos tromboembólicos ou hemorrágicos foi calculada. O nível de significância foi 5%.

Resultados

O TTR médio foi 52,2%. Pacientes com instabilidade de RNI na fase de adaptação tinham um TTR médio mais baixo (46,8%) do que aqueles sem instabilidade (53,9%). Entre os pacientes estudados, 6,9% sofreram eventos hemorrágicos e 8,4% tiveram um acidente vascular cerebral. O grupo com risco mais alto de acidente vascular cerebral e sangramento era composto de pacientes com instabilidade de RNI na fase de adaptação.

Conclusões

A qualidade da anticoagulação nesse hospital terciário no Brasil é semelhante à de centros de países em desenvolvimento. Pacientes com instabilidade de RNI maior na fase de adaptação evoluíram para um TTR médio mais baixo durante o acompanhamento, tinham uma chance de acidente vascular cerebral 4,94 vezes maior e uma chance de sangramento 3,35 vezes maior. Portanto, para esse grupo de pacientes, individualizar a escolha de tratamento anticoagulante seria recomendado, considerando-se a relação custo-benefício.

Improving warfarin therapy through implementation of a hospital-based pharmacist managed clinic in Jamaica

Background

Pharmacist managed warfarin clinics can improve the anticoagulation status of non-valvular patients. The first of such services was implemented at the Cornwall Regional Hospital in Jamaica in 2013.

Objectives

To assess the anticoagulation control of patients on warfarin therapy over six months in the pharmacist managed warfarin clinic at Cornwall Regional Hospital.

Methods

Retrospective docket review for the period January 2014 to December 2016 was done to include data of patients attending routine clinic appointments for at least six months. Age, gender, date of visit, indication for warfarin therapy, warfarin dose and International Normalized Ratio readings were extracted. Percentage time spent in therapeutic range (TTR) was calculated by month for six months using the Rosendaal linear interpolation method. Patient anticoagulation status was categorized as poor (TTR<40%), moderate (TTR=40-64%) or good (TTR≥65%) and anticoagulation status at three months and six months was compared.

Results

For the period of assessment, 52 patients were identified; the median age was 58 years and 36 patients were males. Deep vein thrombosis was the main indication for therapy (22 of 52) and median warfarin weekly dose ranged was 15.0-130 mg. At time of recruitment most of the patients were outside the target INR range (43 of 52). Within one month, the median TTR attained was 31% [IQR 62-10]. This significantly improved by second month to 60% [IQR 82-23] (p=0.001). By month three, the proportion of patients in good, moderate and poor anticoagulant status was 19/51, 15/51 and 17/51 respectively, which at six months changed to 23/51, 12/51. 16/51 respectively; thus, although coagulation status improved from month one to three, there was no significant improvement from month three to month six (p=0.31).

Conclusions

The pharmacist managed warfarin clinic monitoring services were successful in attaining TTRs >40% and sustaining these values over six months. The services should therefore be encouraged.

Evaluating the role of clinical pharmacists in pre-procedural anticoagulation management

OBJECTIVES

While physicians are typically responsible for managing perioperative warfarin, clinic pharmacists may improve pre-procedural decision-making. We assessed the impact of pharmacist-driven care for chronic warfarin-treated patients undergoing outpatient right heart catheterization (RHC).

METHODS

200 warfarin patients who underwent RHC between January 2012 and September 2015 were analyzed. Pharmacist-care (n = 79) was compared to the usual care model (n = 121). The primary outcome was a composite of (1) documentation of anticoagulation plan, (2) holding warfarin at least 5 days prior to procedure, (3) guideline-congruent low molecular weight heparin (LMWH) bridging, and (4) correct LMWH dosing if bridging deemed necessary. Chi-squared test performed to assess the role of pharmacist. A multivariable logistic regression analysis was performed to the composite endpoint, adjusted for the month of procedure.

RESULTS

Compared to the usual care model, pharmacist-driven care (OR 4.69, 95% CI 1.73-12.71, p = 0.002) and date of the procedure (OR 1.06/month, 95% CI 1.01-1.10, p = 0.011) were independently associated with the primary composite outcome. Of the individual outcome components, pharmacist-driven care was only associated with documentation (96.2% vs. 67.8%, OR 9.19, 95% CI 2.19-38.62, p = 0.002). Remaining components including hold warfarin for at least 5 days, appropriate bridging and correct LMWH dosing were not significantly associated with pharmacist-care.

CONCLUSIONS

Pharmacist-care is associated with better guideline-based anticoagulation management, but this was primarily driven by improved documentation. The impact of pharmacist managed peri-procedural anticoagulation on clinical outcomes remains unknown.

Potential Causes and Implications of Low Target Therapeutic Ratio in Warfarin-Treated Patients for Thrombosis Prophylaxis: A Single-Center Experience

Time in therapeutic range (TTR) of international normalized ratio is crucial for the safety and efficacy of anticoagulation with warfarin and it is influenced by many factors. There are limited data about the quality of warfarin therapy and its effects on clinical outcomes in Turkey. The aim of this study is to demonstrate the quality of anticoagulant therapy with warfarin and evaluate the parameters that affect the quality of warfarin therapy. A total of 170 patients with atrial fibrillation (AF; mean age: 62.2 ± 13.3; 69.2% female) treated with warfarin were included in this study. The mean follow-up period was 20 ± 8.4 months. The mean TTR levels of all patients were found to be 54.2% ± 21.4%. The TTR levels were similar in patients with valvular AF (VAF) and nonvalvular AF (NVAF). Logistic regression analysis revealed that elderly, heart failure (HF), and renal dysfunction were independent predictors of lower TTR. There were no significant differences between the VAF and NVAF subgroups regarding the incidence of mortality, stroke, and myocardial infarction. Cox regression analysis revealed that HF, coronary artery disease, and renal dysfunction were independent predictors of clinical outcomes in addition to lower TTR. Our results provide data regarding the quality of anticoagulation with warfarin from a single tertiary center in Istanbul, Turkey. The questions remain in seeking quality improvement in anticoagulation.