ABSTRACT
BACKGROUND: The Time in Therapeutic Range (TTR) is the gold-standard measure used to assess the quality of oral anticoagulation with vitamin K antagonists. However, TTR is a static measure, and International Normalized Ratio (INR) control is a dynamic process. Group-based Trajectory Models (GBTM) can address this dynamic nature by classifying patients into different trajectories of INR control over time. OBJECTIVES: The objective of this study was to assess the quality of INR control in a population-based cohort of new users of vitamin K antagonist with a diagnosis of atrial fibrillation using GBTM. METHODS: We classified patients into different trajectories according to their propensity for being adequately anticoagulated over their first year of treatment using GBTM, and we evaluated the association between trajectories and relevant clinical outcomes over the following year. RESULTS: We included 8024 patients in the cohort who fulfilled the inclusion criteria; the mean number of INR determinations over the first year of treatment was 13.9. We identified 4 differential trajectories of INR control: Optimal (9.7% of patients, TTR: 83.8%), Improving (27.4% of patients, TTR: 61.2%), Worsening (28%; TTR: 69.1%), and Poor control (34.9%; TTR: 41.5%). In adjusted analysis, Poor and Worsening control patients had a higher risk of death than Optimal control patients (hazard ratio: 1.79; IC 95%, 1.36-2.36 and hazard ratio: 1.36; IC 95%, 1.02-1.81, respectively). Differences in other outcomes did not achieve statistical significance, except for a reduced risk of transient ischemic attack in the Improving Control group. CONCLUSIONS: GBTM may contribute to a better understanding and assessment of the quality of oral anticoagulation and may be used in addition to traditional, well-established measures such as TTR.
Subject(s)
Anticoagulants/therapeutic use , Atrial Fibrillation/drug therapy , International Normalized Ratio , Vitamin K/antagonists & inhibitors , Administration, Oral , Aged , Anticoagulants/administration & dosage , Dose-Response Relationship, Drug , Female , Humans , Male , Middle Aged , SpainABSTRACT
BACKGROUND: Worldwide, there is growing evidence that quality of international normalized ratio (INR) control in atrial fibrillation patients treated with Vitamin K Antagonists (VKA) is suboptimal. However, sex disparities in population-based real-world settings have been scarcely studied, as well as patterns of switching to second-line Non-VKA oral anticoagulants (NOAC). We aimed to assess the quality of INR control in atrial fibrillation patients treated with VKA in the region of Valencia, Spain, for the whole population and differencing by sex, and to identify factors associated with poor control. We also quantified switching to Non-VKA oral anticoagulants (NOAC) and we identified factors associated to switching. METHODS: This is a cross-sectional, population-based study. Information was obtained through linking different regional electronic databases. Outcome measures were Time in Therapeutic Range (TTR) and percentage of INR determinations in range (PINRR) in 2015, and percentage of switching to NOAC in 2016, for the whole population and stratified by sex. RESULTS: We included 22,629 patients, 50.4% were women. Mean TTR was 62.3% for women and 63.7% for men, and PINNR was 58.3% for women and 60.1% for men (p<0.001). Considering the TTR<65% threshold, 53% of women and 49.3% of men had poor anticoagulation control (p<0.001). Women, long-term users antiplatelet users, and patients with comorbidities, visits to Emergency Department and use of alcohol were more likely to present poor INR control. 5.4% of poorly controlled patients during 2015 switched to a NOAC throughout 2016, with no sex differences. CONCLUSION: The quality of INR control of all AF patients treated with VKA in 2015 in our Southern European region was suboptimal, and women were at a higher risk of poor INR control. This reflects sex disparities in care, and programs for improving the quality of oral anticoagulation should incorporate the gender perspective. Clinical inertia may be lying behind the observed low rates of switching in patient with poor INR control.
Subject(s)
Anticoagulants/therapeutic use , Atrial Fibrillation/drug therapy , International Normalized Ratio , Vitamin K/antagonists & inhibitors , Aged , Anticoagulants/administration & dosage , Cross-Sectional Studies , Drug Substitution/methods , Female , Humans , International Normalized Ratio/methods , Male , Middle Aged , Sex Factors , SpainABSTRACT
INTRODUCTION: Atrial fibrillation (AF) is one of the leading causes of cerebrovascular mortality and morbidity. Oral anticoagulants (OACs) have been shown to reduce the incidence of cardioembolic stroke in patients with AF, adherence to treatment being an essential element for their effectiveness. Since the release of the first non-vitamin K antagonist oral anticoagulant, several observational studies have been carried out to estimate OAC adherence in the real world using pharmacy claim databases or AF registers. This systematic review aims to describe secondary adherence to OACs, to compare adherence between OACs and to analyse potential biases in OAC secondary adherence studies using databases. METHODS AND ANALYSIS: We searched on PubMed, SCOPUS and Web of Science databases (completed in 26 September 2018) to identify longitudinal observational studies reporting days' supply adherence measures with OAC in patients with AF from refill databases or AF registers. The main study endpoint will be the percentage of patients exceeding the 80% threshold in proportion of days covered or the medication possession ratio. Two reviewers will independently screen potential studies and will extract data in a structured format. A random-effects meta-analysis will be carried out to pool study estimates. The risk of bias will be assessed using the Newcastle-Ottawa Scale for observational studies and we will also assess some study characteristics that could affect days' supply adherence estimates. ETHICS AND DISSEMINATION: This systematic review using published aggregated data does not require ethics approval according to Spanish law and international regulations. The final results will be published in a peer-review journal and different social stakeholders, non-academic audiences and patients will be incorporated into the diffusion activities. PROSPERO REGISTRATION NUMBER: CRD42018095646.