Prevalence, incidence and persistence of etanercept and adalimumab in Norway 2005–2009

Authors

  • Milada Mahic,

    Corresponding author
    1. Department of Pharmacoepidemiology, Division of Epidemiology, Norwegian Institute of Public Health, Oslo, Norway
    • Department of Pharmacoepidemiology, Division of Epidemiology, Norwegian Institute of Public Health, Marcus Thranes Gate 6, Post Box 4404, Nydalen, 0403 Oslo, Norway.
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  • Svetlana Skurtveit,

    1. Department of Pharmacoepidemiology, Division of Epidemiology, Norwegian Institute of Public Health, Oslo, Norway
    2. Norwegian Centre for Addiction Research, University of Oslo, Oslo, Norway
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  • Randi Selmer,

    1. Department of Pharmacoepidemiology, Division of Epidemiology, Norwegian Institute of Public Health, Oslo, Norway
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  • Marit Rønning,

    1. Department of Pharmacoepidemiology, Division of Epidemiology, Norwegian Institute of Public Health, Oslo, Norway
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  • Kari Furu

    1. Department of Pharmacoepidemiology, Division of Epidemiology, Norwegian Institute of Public Health, Oslo, Norway
    2. Department of Pharmacy, University of Tromsø, Tromsø, Norway
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ABSTRACT

Purpose

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. Copyright © 2010 John Wiley & Sons, Ltd.

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