title: Prevalence, incidence and persistence of etanercept and adalimumab in Norway 2005-2009.
abstract: OBJECTIVE
  Examining the prevalence, incidence and persistence of use of etanercept and adalimumab in Norway during 2005-2009.
  
  
  METHODS
  We retrieved data from the nationwide Norwegian Prescription Database (NorPD) for all individuals who were dispensed etanercept or adalimumab from pharmacies during 2005-2009. The NorPD covers the total Norwegian population in ambulatory care. Key measurements were one-year prevalence, incidence rate and persistence (minimum refill).
  
  
  RESULTS
  The one-year prevalence for etanercept and adalimumab was 1.59‰ (n = 3840) for men and 1.85‰ (n = 4483) for women in 2009, an increase from 0.76‰ (n = 1752) for men and 1.21‰ (n = 2830) for women from 2005. The prevalence increased during the entire study time in all ages, with the highest prevalence for both genders among those aged 50-69. A total of 7786 individuals started therapy with etanercept or adalimumab during 2005-2009. Annual incidence of new users increased with 23.6% from 2005 to 2009. Sixty one percent of new users redeemed etanercept as the first drug, and 39% redeemed adalimumab. Sixty seven percent of all individuals who received etanercept or adalimumab in 2005 refilled their prescription at least once each of the following 4 years.
  
  
  CONCLUSIONS
  Both prevalence and incidence of use of etanercept and adalimumab increased in Norway during 2005-2009. A high proportion of the individuals redeemed prescriptions regularly over 5 years.
authors.affiliation: Department of Pharmacoepidemiology, Division of Epidemiology, Norwegian Institute of Public Health, Oslo, Norway. milada.mahic@fhi.no
authors.forename: Milada
authors.initials: M
authors.lastname: Mahic
authors.forename: Svetlana
authors.initials: S
authors.lastname: Skurtveit
authors.forename: Randi
authors.initials: R
authors.lastname: Selmer
authors.forename: Marit
authors.initials: M
authors.lastname: Rønning
authors.forename: Kari
authors.initials: K
authors.lastname: Furu
mesh_terms: D000068879:Adalimumab; D000911:Antibodies, Monoclonal / Q000008:administration & dosage* / Q000627:therapeutic use; D061067:Antibodies, Monoclonal, Humanized; D016208:Databases, Factual; D017723:Drug Utilization Review / Q000706:statistics & numerical data*; D000068800:Etanercept; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000008:administration & dosage* / Q000627:therapeutic use; D015994:Incidence; D008297:Male; D009664:Norway; D015995:Prevalence; D018124:Receptors, Tumor Necrosis Factor / Q000008:administration & dosage* / Q000627:therapeutic use; D012737:Sex Factors; D013997:Time Factors
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D007074:Immunoglobulin G; D018124:Receptors, Tumor Necrosis Factor; D000068879:Adalimumab; D000068800:Etanercept