Postmarketing Study of ORTHO EVRA (Norelgestromin and Ethinyl Estradiol Contraceptive Patch) in Relation to Venous Thromboembolism (Blood Clots), Stroke and Heart Attacks
Condition: Contraception; Female Contraception
MeSH terms: Thromboembolism; Venous Thromboembolism
Study type: Observational

Summary: 
      The purpose of the study is to assess the occurrence of venous thromboembolism (blood clots),
      stroke, and heart attack in current users of ORTHO EVRA compared to current users of
      norgestimate-containing oral contraceptives with 35 mcg ethinyl estradiol with special
      attention to duration of use. The study uses data from the PharMetrics Patient-Centric
      Database and MarketScan database, which are US medical claims databases.
    

Detailed description: 
      ORTHO EVRA is a newly developed transdermal (absorbed through the skin) contraceptive (birth
      control) system (a "patch") available in the U.S. since April 2002. The study uses data from
      the PHARMetrics and MarketScan databases to assess the occurrence of venous thromboembolism
      (blood clots), ischemic stroke (blockage of an artery that supplies blood to the brain), and
      acute myocardial infarction (heart attack) in current first time users of ORTHO EVRA compared
      to current first time users of norgestimate-containing oral (by mouth) contraceptives with 35
      mcg ethinyl estradiol. The PHARMetrics database is an ongoing longitudinal database with
      information on about 17 million people. It is made up of data contributed by managed care
      plans in the United States and contains information on paid claims for pharmaceuticals,
      medical diagnoses and procedures, and demographic (age, race, etc) information. There will be
      3 sets of cases reflecting women who have a first-time recorded claim for an ICD-9
      (International Classification of Diseases , ninth revision) diagnosis during the study period
      (a) venous thrombosis or pulmonary embolism (blood clot in the lung) with hospitalization
      during the study period and who had subsequent claims for anticoagulant treatment, (b)
      ischemic stroke and who were hospitalized, (c) acute myocardial infarction or acute coronary
      revascularization (restoration of blood supply to the heart) and who were hospitalized. Three
      separate sets of controls (patients) will be identified for each outcome. One analysis will
      estimate the relative risk of idiopathic (of unknown cause) ischemic stroke or myocardial
      infarction, and another analysis will estimate the relative risk of idiopathic venous
      thromboembolism (deep vein thrombosis or pulmonary embolism). A specific analysis called a
      "Conditional logistic regression" (conditional on the matching factors) will be used in this
      study. Analyses will be stratified by calendar year. The analyses will be repeated including
      non-idiopathic (ie, of known cause) cases of venous thromboembolism, stroke, and heart
      attacks. The original study runs through March 2005, with updates to through August 2006, and
      October 2007. A transdermal patch containing 6 mg norelgestromin (NGM) and 0.75 mg ethinyl
      estradiol (EE) is worn for 1 week and replaced weekly for 3 consecutive weeks; the fourth
      week is patch-free. Monophasic (all pills have the same hormones at the same concentration)
      or triphasic (3 different pills are taken during the cycle) oral contraceptive pill is taken
      for 21 consecutive days followed by no pill or a drug-free pill for 7 days.
    

Intervention name(s): Monophasic or triphasic Oral contraceptive tablet; Ortho Evra transdermal patch containing 6 mg NGMN/0.75 mg EE
Intervention type(s): Drug; Drug
Intervention description(s): fourth week is patch free; worn for 1 week and replaced for 3 consecutive weeks
Intervention MeSH terms: Contraceptive Agents; Ortho Evra; Contraceptives, Oral
Observational model: Case-Control
Time perspective: Retrospective
Sampling method: Non-Probability Sample
Study population: 
        Data collected from PharMetrics, a United States based, ongoing longitudinal database of
        data contributed by managed care plans that contains information on unpaid claims for
        pharmaceuticals, medical diagnoses and procedures and from MarketScan database, a US health
        care claims database.
      
Keywords: Contraception; Hormonal contraception; Oral contraception; Ethinyl estradiol, Progestin, Contraception; Transdermal