Hemorrhage Risk Prescribed Arixtra

Study Overview
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Brief Summary
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Arixtra (fondaparinux sodium) was the first selective Factor Xa inhibitor to be marketed. As with all anticoagulants, an important adverse event associated with Arixtra use is haemorrhage. Previous studies using clinical trial and observational data show no difference in the risk of haemorrhage in patients treated with Arixtra compared to (low molecular weight heparins) LMWHs. This study will assess the risk of haemorrhage in major orthopaedic surgery patients (hip fracture surgery and/or hip/knee replacement surgery) treated with either Arixtra or LMWH for thromboprophylaxis and will provide additional observational data from a European country to strengthen the comprehensive review of haemorrhage and the post-marketing safety of Arixtra. All patients age 18 years and older with a primary discharge diagnosis for hip fracture surgery and/or a hospitalization for hip and/or knee replacement surgery from the PHARMO RLS database in the Netherlands are eligible for participation. For study inclusion patients must receive either Arixtra or LMWH as initial in-hospital thromboprophylactic agent and have at least three months in the PHARMO RLS database before cohort entry date. Patients with a history of hospitalization for haemorrhage, renal failure or liver failure in the past 3 months will be excluded. Descriptive statistics, including gender, age, length of treatment, co-morbidities, concomitant medications, and other covariates will be calculated. Data for this study were obtained from different registers in the PHARMO medical record linkage system (PHARMO RLS) in the Netherlands. The PHARMO medical record linkage system is a population-based patient-centric data tracking system that includes high quality and complete information of patient demographics, drug dispensing, and hospital morbidity records of approximately 2.3 million community-dwelling inhabitants of 48 geo-demographic areas in the Netherlands. The PHARMO registers are linked on a patient level and contain unprecedented accurate and complete information required for the study. The out patient database contains drug dispensing data in the U-Expo database are encoded according to standards based upon the Z-Index drug database (www.z-index.nl). Therefore, it is possible to identify and classify drug use in time, both on the basis of national and international classification schemes as well as on the basis of individual active ingredients and administration forms. Of each dispensed drug, the Anatomical Therapeutic Chemical (ATC) code, the dispensing date, the prescriber, the prescribed dosage regimen, the dispensed quantity, the cost and the estimated legend duration of use are available. The hospital pharmacy database comprises hospital pharmacy data collected in a growing number of non-academic hospitals in the Netherlands. Currently, data are collected on patient level for more than one million patients from a representative sample of non-academic hospital pharmacies scattered over the Netherlands. The hospital pharmacy database includes data on in-patient medication orders such as type of drug, dose, and time of administration and duration of use. The Dutch Medical Register (LMR) is the data source comprising all hospital admissions in the Netherlands (www.prismant.nl). These records include detailed information concerning the primary and secondary discharge diagnoses, diagnostic, surgical and treatment procedures, type and frequency of consultations with medical specialists and dates of hospital admission and discharge. All diagnoses are coded according to the International Classification of Diseases, 9th edition (ICD-9-CM). Currently, data until December 2008 are available.

Detailed Description
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Patients were not recruited for nor enrolled in this study. This study is a retrospective observational study. Data from medical records or insurance claims databases are anonymised and used to develop a patient cohort. All diagnoses and treatment are recorded in the course of routine medical practice.

Official Title
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Risk of Hemorrhage in Patients Prescribed Arixtra Compared to LMWH

Conditions
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Thrombosis, Venous

Intervention / Treatment
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* Drug: Fondaparinux sodium
* Drug: Low molecular weight heparin (LMWH)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18 years and older; Treatment with either Arixtra or LMWH as initial in-hospital thromboprophylactic agent; At least three months history in the PHARMO RLS database before cohort entry date Exclusion Criteria: Hospitalization for haemorrhage, renal failure or liver failure in the 3 months before cohort entry date

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Prophylaxis following major orthopedic surgery<br>Patients age 18 years and older in the PHARMO RLS database treated with either fondaparinux sodium or LMWH for thromboprophylaxis following hip fracture and/or hip/knee replacement surgery. | Drug: Fondaparinux sodium<br>* Fondaparinux sodium for thromboprophylaxis (ATC: B01AX05)<br>Drug: Low molecular weight heparin (LMWH)<br>* LMWH including: dalteparin, nadroparin, enoxaparin or tinzaparin (ATC:B01AB (excluding B01AB01))<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Participants With the Indicated Types of Haemorrhages During Hospitalization or Follow-up for Major Orthopaedic Surgery of Lower Limbs (MOSLL) | Haemorrhages during MOSLL hospitalization or follow-up as identified by ICD-9-CM codes were measured. The PHARMO medical record linkage system (RLS), in the Netherlands, is a population-based patient-centric data tracking system that includes high quality/ complete information of patient demographics, drug dispensing, and hospital morbidity records of approximately 2.3 million inhabitants in the Netherlands. | Follow-up continued until the date of first event, death, end of initial therapy, hospital discharge, end of follow-up in PHARMO RLS, or 60 days after discharge, whichever came first | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Participants With the Indicated Haemorrhages During Hospitalization for Major Orthopaedic Surgery of Lower Limbs (MOSLL) | Haemorrhages during MOSLL hospitalization or follow-up as identified by ICD-9-CM codes were measured. The PHARMO medical record linkage system (RLS), in the Netherlands, is a population-based patient-centric data tracking system that includes high quality/ complete information of patient demographics, drug dispensing, and hospital morbidity records of approximately 2.3 million inhabitants in the Netherlands. | Follow-up continued until the date of first event, death, end of initial therapy, hospital discharge, end of follow-up in PHARMO RLS, or 60 days after discharge, whichever came first. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Haemorrhage, Thromboprophylaxis