Effectiveness and safety of drugs used for stroke prevention in a cohort of non-valvular atrial fibrillation patients from a primary care electronic database

Thrombosis and thrombocytopenia after vaccination against and infection with SARS-CoV-2 in Catalonia, Spain

Population-based studies can provide important evidence on the safety of COVID-19 vaccines. Here we compare rates of thrombosis and thrombocytopenia following vaccination against SARS-CoV-2 with the background (expected) rates in the general population. In addition, we compare the rates of the same adverse events among persons infected with SARS-CoV-2 with background rates. Primary care and linked hospital data from Catalonia, Spain informed the study, with participants vaccinated with BNT162b2 or ChAdOx1 (27/12/2020-23/06/2021), COVID-19 cases (01/09/2020-23/06/2021) or present in the database as of 01/01/2017. We included 2,021,366 BNT162b2 (1,327,031 with 2 doses), 592,408 ChAdOx1, 174,556 COVID-19 cases, and 4,573,494 background participants. Standardised incidence ratios for venous thromboembolism were 1.18 (95% CI 1.06-1.32) and 0.92 (0.81-1.05) after first- and second dose BNT162b2, and 0.92 (0.71-1.18) after first dose ChAdOx1. The standardised incidence ratio for venous thromboembolism in COVID-19 was 10.19 (9.43-11.02). Standardised incidence ratios for arterial thromboembolism were 1.02 (0.95-1.09) and 1.04 (0.97-1.12) after first- and second dose BNT162b2, 1.06 (0.91-1.23) after first-dose ChAdOx1 and 4.13 (3.83-4.45) for COVID-19. Standardised incidence ratios for thrombocytopenia were 1.49 (1.43-1.54) and 1.40 (1.35-1.45) after first- and second dose BNT162b2, 1.28 (1.19-1.38) after first-dose ChAdOx1 and 4.59 (4.41- 4.77) for COVID-19. While rates of thrombosis with thrombocytopenia were generally similar to background rates, the standardised incidence ratio for pulmonary embolism with thrombocytopenia after first-dose BNT162b2 was 1.70 (1.11-2.61). These findings suggest that the safety profiles of BNT162b2 and ChAdOx1 are similar, with rates of adverse events seen after vaccination typically similar to background rates. Meanwhile, rates of adverse events are much increased for COVID-19 cases further underlining the importance of vaccination.

Real-world cost-effectiveness analysis of NOACs versus VKA for stroke prevention in Spain

Aims

A Markov model was adapted to assess the real-world cost-effectiveness of rivaroxaban, dabigatran and apixaban. Each of these non-vitamin K antagonist oral anticoagulants was compared with vitamin K antagonist for stroke prevention in patients with non-valvular atrial fibrillation in Spain.

Methods

All inputs were derived from real-world studies: baseline patient characteristics, clinical event rates, as well as persistence rates for the vitamin K antagonist treatment option. A meta-analysis of real-world studies provided treatment effect and persistence data for rivaroxaban, dabigatran and apixaban, each compared with vitamin K antagonist therapy. The model considered 3-month cycles over a lifetime horizon. The model outcomes included different costs, quality-adjusted life years and life-years gained. Sensitivity analyses were performed to test the robustness of the model.

Results

When compared with vitamin K antagonist, rivaroxaban incurred incremental costs of €77 and resulted in incremental quality-adjusted life years of 0.08. The incremental cost per quality-adjusted life year was €952. For the same comparison, the incremental cost per quality-adjusted life year for dabigatran was €4,612. Finally, compared with vitamin K antagonist, the incremental cost per quality-adjusted life year for apixaban was €32,015. The sensitivity analyses confirmed the robustness of the base case results. The probabilities to be cost-effective versus vitamin K antagonist were 94%, 86% and 35%, respectively, for rivaroxaban, dabigatran and apixaban, considering a willingness-to-pay threshold of €22,000 per quality-adjusted life year gained, based on a cost-effectiveness study of the Spanish National Health System.

Conclusion

These results suggest that rivaroxaban and dabigatran are cost-effective versus vitamin K antagonist for stroke prevention in non-valvular atrial fibrillation, from the Spanish National Health System perspective.

Cost and burden of poor anticoagulation control with vitamin K antagonists in patients with nonvalvular atrial fibrillation in Spain

INTRODUCTION AND OBJECTIVES

The aim of this analysis was to evaluate the burden and cost of complications due to poor anticoagulation control in patients with nonvalvular atrial fibrillation (NVAF) treated with vitamin K antagonists (VKA) in Spain.

METHODS

An analytical model was used to estimate annual differences in ischemic stroke, major bleeding, deaths, costs, and potential years of life lost between patients with poor anticoagulation control (time in therapeutic range <65%) and adequate control (time in therapeutic range ≥ 65%) with a 1-year time horizon. Information on the target population (patients ≥ 65 years), event rates, and costs were obtained from national sources. Direct costs in euros (2018) were included from the perspective of the national health system (NHS) and direct and indirect costs from the societal perspective. A sensitivity analysis was performed with post-hoc data from the SPORTIF III/V trials.

RESULTS

We analyzed a hypothetical cohort of 594 855 patients, 48.3% with poor anticoagulation control, with an increase of 2321 ischemic strokes, 2236 major bleeding events and 14 463 deaths, and an annual incremental cost between €29 578 306 from the NHS perspective and €75 737 451 from the societal perspective. The annual impact of mortality was 170 502 potential years of life lost. The results of the sensitivity analysis showed that the annual cost would reach €97 787 873 from the societal perspective.

CONCLUSIONS

Poor anticoagulation control with AVK has a strong impact on loss of health and on increased spending for the NHS.

Quality of reporting of drug exposure in pharmacoepidemiological studies

Purpose

Exposure definitions vary across pharmacoepidemiological studies. Therefore, transparent reporting of exposure definitions is important for interpretation of published study results. We aimed to assess the quality of reporting of exposure to identify where improvement may be needed.

Method

We systematically reviewed observational pharmacoepidemiological studies that used routinely collected health data, published in 2017 in six pharmacoepidemiological journals. Reporting of exposure was scored using 11 items of the ISPE‐ISPOR guideline on reporting of pharmacoepidemiological studies.

Results

Of the 91 studies included, all studies reported the type of exposure (100%), while most reported the exposure risk window (85%) and the exposure assessment window (98%). Operationalization of the exposure window was described infrequently: 16% (14/90) of the studies explicitly reported the presence or absence of an induction period if applicable, 11% (5/47), and 35% (17/49) reported how stockpiling and gaps between exposure episodes were handled, respectively, and 35% (17/49) explicitly mentioned the exposure extension. Switching/add‐on was reported in 62% (50/81). How switching between drugs was dealt with and specific drug codes were reported in 52 (57%) and 24 (26%) studies, respectively.

Conclusion

Publications of pharmacoepidemiological studies frequently reported the type of exposure, the exposure risk window, and the exposure assessment window. However, more details on exposure assessment are needed, especially when it concerns the operationalization of the exposure risk window (eg, the presence or absence of an induction period or exposure extension, handling of stockpiling and gaps, and specific codes), to allow for correct interpretation, reproducibility, and assessment of validity.

[Effectiveness, safety and costs of stroke prevention in non-valvular auricular fibrillation. Study of cohorts matched by Propensity score]

OBJECTIVE

To analyze the use, effectiveness, safety and costs of stroke prevention in non-valvular atrial fibrillation (AF) in patients initiating treatment with dabigatran or vitamin K antagonists (VKA).

SETTING

Primary Care (PC) at the Catalan Health Institute (ICS) in Catalonia, during 2011-2013.

PARTICIPANTS

Patients attended in ICS PC centres with a registered diagnosis of AF who initiate dabigatran or VKA.

INTERVENTIONS

Not applicable MAIN MEASUREMENTS: Number of prescriptions and reimbursements of dabigatran and VKA, incidence of stroke and haemorrhages, incidence of mortatlity, number of sickness leave, and costs associated to all the previous variables.

RESULTS

14,930 patients were included; 94.6% initiated VKA and 5.4%, dabigatran. Dabigatran patients were younger and with less comorbidity. There were no statistically significant differences between VKA and dabigatran in the risk of stroke, haemorrhages or death. The costs associated to AF management were higher for PC visits in the VKA group, and higher for laboratory and pharmacy in the dabigatran group, although overall costs were not statistically different.

CONCLUSIONS

Most patients initiated VKA. We found no differences between VKA and dabigatran in the risk of stroke, haemorrhages or mortality.

Incidence of direct oral anticoagulant use in patients with nonvalvular atrial fibrillation and characteristics of users in 6 European countries (2008-2015): A cross-national drug utilization study

Aims

To estimate the incidence of direct oral anticoagulant drug (DOAC) use in patients with nonvalvular atrial fibrillation and to describe user and treatment characteristics in 8 European healthcare databases representing 6 European countries.

Methods

Longitudinal drug utilization study from January 2008 to December 2015. A common protocol approach was applied. Annual period incidences and direct standardisation by age and sex were performed. Dose adjustment related to change in age and by renal function as well as concomitant use of potentially interacting drugs were assessed.

Results

A total of 186 405 new DOAC users (age ≥18 years) were identified. Standardized incidences varied from 1.93–2.60 and 0.11–8.71 users/10 000 (2011–2015) for dabigatran and rivaroxaban, respectively, and from 0.01–8.12 users/10 000 (2012–2015) for apixaban. In 2015, the DOAC incidence ranged from 9 to 28/10 000 inhabitants in SIDIAP (Spain) and DNR (Denmark) respectively. There were differences in population coverage among the databases. Only 1 database includes the total reference population (DNR) while others are considered a population representative sample (CPRD, BIFAP, SIDIAP, EGB, Mondriaan). They also varied in the type of drug data source (administrative, clinical). Dose adjustment ranged from 4.6% in BIFAP (Spain) to 15.6% in EGB (France). Concomitant use of interacting drugs varied between 16.4% (SIDIAP) and 70.5% (EGB). Cardiovascular comorbidities ranged from 25.4% in Mondriaan (The Netherlands) to 82.9% in AOK Nordwest (Germany).

Conclusion

Overall, apixaban and rivaroxaban increased its use during the study period while dabigatran decreased. There was variability in patient characteristics such as comorbidities, potentially interacting drugs and dose adjustment. (EMA/2015/27/PH).

Annual costs attributed to atrial fibrillation management: cross-sectional study of primary healthcare electronic records

Atrial fibrillation (AF) is the most common chronic arrhythmia, with increasing healthcare and economic burden and a prevalence which increases with progressive ageing. This study aims to describe overall annual costs per patient for management of non-valvular AF in a primary healthcare (PHC) setting and compare these costs between the groups of patients treated with vitamin K antagonists, antiplatelets or non-treated through a population-based study conducted with electronic health records. We analysed annual costs per person of 19,787 patients in 2012; PHC visits, hospital admissions, AF-related events requiring hospital admission, referrals to secondary specialists, sick leave, diagnostic tests and laboratory tests at PHC level, including INR determinations performed in PHC, and drug therapy. Higher costs of AF management were associated with increasing age, male sex, stroke and bleeding risks, comorbidities and occurrence of events associated to AF. The sensitivity analyses conducted showed that PHC visits and hospitalizations represented the most important part of overall costs for all patients.

Impact of Medication Adherence on Mortality and Cardiovascular Morbidity: Protocol for a Population-Based Cohort Study

BACKGROUND

Cardiovascular disease (CVD) is a group of disorders of the heart and blood vessels, such as coronary heart disease (CHD), cerebrovascular disease, and peripheral artery disease. CVD is the leading threat to global health, whether measured by mortality, morbidity, or economic cost. Long-term administration of aspirin, statins, beta-blockers, and angiotensin-converting enzyme inhibitors or angiotensin-receptor blockers improves survival in patients with stablished coronary heart disease. Nevertheless, adherence to prescribed medication is poor for long-term drug treatment.

OBJECTIVE

We aim to assess the relationship between adherences to the four pharmacological groups recommended for secondary prevention and the clinical outcomes of cardiovascular morbidity and mortality in patients with established CHD according to the level of adherence to these drugs in a population of incident cases of acute coronary syndrome (ACS).

METHODS

Population-based cohort study of patients with a first episode of ACS during 2006-2015 in the Information System for Research in Primary Care (SIDIAP) database. We will estimate adherence to these drugs. The primary endpoint is a composite of all-cause mortality, ACS, and ischaemic stroke. Bivariate analyses will be performed estimating odds ratios for categorical variables and mean differences for continuous variables. Hazard ratios for adherences will be calculated for outcome events using Cox proportional hazard regression models, and proportionality of hazards assumption will be tested.

RESULTS

We expect to estimate adherence to all four study treatments, the incidence of MACE, and to analyze if this incidence is associated with the level of drug adherence.

CONCLUSIONS

We expect to find that adherent patients have a lower risk of the primary endpoints compared with nonadherent patients.

TRIAL REGISTRATION

This study protocol was classified as EPA-OD by the AEMPS (IJG-EST-2017-01-2017-01, 07/04/2017) and registered in the EU PAS register (EUPAS19017, 09/05/2017).

Health Data for Public Health: Towards New Ways of Combining Data Sources to Support Research Efforts in Europe

Objectives: To present the European landscape regarding the re-use of health administrative data for research. Methods: We present some collaborative projects and solutions that have been developed by Nordic countries, Italy, Spain, France, Germany, and the UK, to facilitate access to their health data for research purposes. Results: Research in public health is transitioning from siloed systems to more accessible and re-usable data resources. Following the example of the Nordic countries, several European countries aim at facilitating the re-use of their health administrative databases for research purposes. However, the ecosystem is still a complex patchwork, with different rules, policies, and processes for data provision. Conclusion: The challenges are such that with the abundance of health administrative data, only a European, overarching public health research infrastructure, is able to efficiently facilitate access to this data and accelerate research based on these highly valuable resources.