Changing trends in antiepileptic drug prescribing in girls of child-bearing potential
- 1Centre for Paediatric Pharmacy Research, School of Pharmacy, University of London, London, UK
- 2Institute of Child Health, University College London, London, UK
- 3Task-force in Europe for Drug Development for the Young (TEDDY)
- 4Twinwoods Health Resource Centre, Bedfordshire and Luton Partnership NHS Trust, Clapham, Bedfordshire, UK
- 5Centre for Paediatric Epidemiology and Biostatistics, Institute of Child Health, University College London, London, UK
- Ian Wong, Centre for Paediatric Pharmacy Research, School of Pharmacy, University of London, Level 1, BMA House, Tavistock Square, London WC1H 9JP, UK;
- Accepted 15 February 2009
- Published Online First 22 March 2009
Objective: To characterize trends in prescribing carbamazepine (CBZ), sodium valproate (VPA) and lamotrigine (LTG) in adolescent females in the UK and to examine possible reasons for changing trends.
Design: Population-based observational study.
Setting: UK General Practice Research Database between 1 January 1993 and 31 December 2006.
Patients: 12–18-year-old subjects who were issued ⩾1 CBZ, VPA or LTG prescription.
Main outcome measures: Prescribing prevalences stratified by age, gender and antiepileptic drug.
Results: 5417 patients (47.6% females) were prescribed 147 111 prescriptions for CBZ (34.5%), VPA (38.6%) or LTG (26.9%). The prevalence of LTG prescribing in females increased from 0.08 (95% CI 0.04 to 0.12) to 0.80 (95% CI 0.70 to 0.89) per 1000 female population. Conversely, the prevalence in females of CBZ and VPA prescribing significantly decreased from 1.00 (95% CI 0.85 to 1.15) to 0.51 (95% CI 0.44 to 0.58) and from 0.94 (95% CI 0.80 to 1.09) to 0.63 (95% CI 0.55 to 0.72), respectively. This 10-fold rise in LTG prescribing in females is much higher than the fivefold rise in males from 0.09 (95% CI 0.05 to 0.14) to 0.47 (95% CI 0.40 to 0.54) per 1000 male population.
Conclusion: The practice of prescribing antiepileptic drugs in adolescents has changed gradually over the last decade. More females aged 12–18 years are prescribed LTG than CBZ or VPA and the increase is much greater than for males. The increase in LTG prescribing mirrors a corresponding decrease in both VPA and CBZ. Concerns about potential problems to offspring appear to be affecting prescription trends in adolescent females of child-bearing potential.
Funding: This study is part of the Network of Excellence TEDDY (Task-force in Europe for Drug Development for the Young) supported by the EC-Sixth Framework Program (Contract no. 0005216 LSHB-CT-2005-005126). IW’s post was funded by a Department of Health Public Health Career Scientist Award to investigate the safety of psychotropic medications in children. The views expressed are those of the authors and not of the Department of Health.
Competing interests: IW has received funding from various pharmaceutical companies including GlaxoSmithKline, Janssen-Cilag and Pfizer (manufacturers of lamotrigine, topiramate and gabapentin) but none was related to the present study. FB has been sponsored to attend conferences and has received research and equipment grants from various pharmaceutical companies. He is the former editor-in-chief of a journal sponsored by GlaxoSmithKline. RA, MM and AW have no competing interests.
Ethics approval: Ethics approval was granted by the GPRD Scientific and Ethical Advisory Group.