title: A comparison of therapy continuation rates of different hormone replacement agents: a 9-month retrospective, longitudinal analysis of pharmacy claims among new users.
abstract: OBJECTIVE
  To estimate the rate of therapy continuation among women using six different hormone replacement therapies (HRTs).
  
  
  METHODS
  A retrospective, longitudinal analysis of pharmacy claims data was conducted for 7,120 women who were new users of six HRT regimens. Continuation rates of therapies were examined at the end of the 9-month period. In addition, the odds ratio of continuation for each product was determined using a logistic model, which controlled for the potential influence of a patient's age and a provider's age, gender, specialty, and geographical location.
  
  
  RESULTS
  Treatment continuation rates at the end of the 9-month period were significantly higher among patients prescribed oral 1 mg norethindrone acetate/5 microgram ethinyl estradiol (EE) (femhrt, Pfizer Inc, New York, NY, USA) compared with other HRT regimens. Patients prescribed 1 mg norethindrone acetate/5 microgram EE were 52% more likely to continue therapy compared with patients prescribed 0.625 mg conjugated equine estrogens/2.5 mg or 5 mg medroxyprogesterone acetate (Prempro, Wyeth, Madison, NJ, USA). Significantly higher rates of therapy continuation were seen in women aged 55 years or older, those who did not switch HRT during the analysis, those who received care in the central and northeast regions of the United States, and those who were seen by obstetricians/gynecologists (v primary care physicians) or female (v male) providers.
  
  
  CONCLUSIONS
  The higher rates of treatment continuation seen with newer continuous combined HRTs, such as 1 mg norethindrone acetate/5 microgram EE, may lead to improved long-term compliance and, therefore, better protection against osteoporosis in postmenopausal women.
authors.affiliation: Department of Obstetrics and Gynecology, George Washington University School of Medicine, Washington, DC, USA.
authors.forename: James A
authors.initials: JA
authors.lastname: Simon
authors.forename: Susan
authors.initials: S
authors.lastname: Wysocki
authors.forename: Jane
authors.initials: J
authors.lastname: Brandman
authors.forename: Kirsten
authors.initials: K
authors.lastname: Axelsen
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D015331:Cohort Studies; D015914:Estrogen Replacement Therapy / Q000191:economics / Q000706:statistics & numerical data*; D019304:Ethinyl Estradiol-Norgestrel Combination / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007345:Insurance Claim Review; D007356:Insurance, Pharmaceutical Services / Q000706:statistics & numerical data*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D010349:Patient Compliance; D010818:Practice Patterns, Physicians'; D012189:Retrospective Studies; D014481:United States / Q000453:epidemiology
chemical_list: D019304:Ethinyl Estradiol-Norgestrel Combination