Paediatric Anti-depressant Prescribing In Primary Care

APC SUN1, B Kirby1, PJ Helms1, C Black1, CR Simpson2, JS McLay1. 1Division of Applied Health Science, University of Aberdeen, Aberdeen, UK, 2eHealth Research Group, Centre for Population Health Sciences, University of Edinburgh, Edinburgh, UK

Introduction

Depression in children is associated with poor school performance, low self-esteem and suicide. Currently fluoxetine is the only antidepressant licensed for this indication. The extent of antidepressant prescribing and associated adverse drug reactions in childhood and early adolescence are poorly documented.

Aims

To identify anti-depressant utilisation in Scottish children and the potential for drug discontinuation, as an indicator of possible adverse drug reactions (ADRs).

Methods

Prescribing data held within the Primary Care Clinical Informatics Unit Research (PCCIUR) database, which holds information on approximately 1 million patients, was used to assess prescribing and discontinuation of anti-depressant in children aged 16 years and younger, for the period 2006-2009.

Results

During the study period 464 of 448154 registered children were initiated on an anti-depressant, an exposure incidence of 0.1%.

Fluoxetine (n=210) was the most frequently prescribed followed by Amitriptyline (n=149) and Citalopram (n=67) with remainder (n=38) encompassing a variety of other antidepressants including imipramine, sertraline, nortiptyline and doxepin. Females formed the majority of recipients, 65.8% for amytriptyline, 67.6% for fluoxitine and 68.7% for citalopram.

Compared to the other antidepressants, amitriptyline was prescribed to both young children and adolescent (median age was 15, IQR 12-16 years old) whereas fluoxetine and citalopram were more commonly used in older children (median age 16, IQR 15-16 years). Children prescribed amitriptyline discontinued the prescription significantly earlier (p= 0.002 at 1 month) compared to the other antidepressants, with 53.7% discontinue within 1 month and 69.1% by 3 months, in comparison to discontinuation rates of 34.8% within 1 month and 52.4% by 3 months for fluoxetine and 41.8% at 1 month and 56.7% by 3 months for citalopram.

Once the index prescription was discontinued, switching to another anti-depressants occurred in 5.7% of patients prescribed fluoxetine, 11.9% of patients prescribed citalopram and 2% of patients prescribed amitriptyline.

Using routinely collected healthcare data permitted the identification of children prescribed anti-depressants, the discontinuation rate, assessment of age, gender and co-prescribing patterns.

Conclusion

Routinely acquired primary care healthcare data can be used to assess medication prescribing profiles and drug discontinuations in children. The high discontinuations for antidepressants observed in the present study are similar to those reported in clinical trials and observational studies (1-3). Further analysis including linkage with other routinely acquired data sets and/or direct enquiry to prescribers would be required in order to assess the reasons for discontinuation and switching and in the identification of unreported ADRs.

References

(1) Murray ML, de Vries CS, Wong IC. A drug utilisation study of antidepressants in children and adolescents using the General Practice Research Database. Arch Dis Child 2004 Dec;89(12):1098-1102.

(2) Brent D, Emslie G, Clarke G, Wagner KD, Asarnow JR, Keller M, et al. Switching to another SSRI or to venlafaxine with or without cognitive behavioral therapy for adolescents with SSRI-resistant depression: the TORDIA randomized controlled trial. JAMA 2008 Feb 27;299(8):901-913.

(3) Demyttenaere K, Enzlin P, Dewe W, Boulanger B, De Bie J, De Troyer W, et al. Compliance with antidepressants in a primary care setting, 1: Beyond lack of efficacy and adverse events. J Clin Psychiatry 2001;62(Suppl 22):30-33.