Unlicensed use of metformin in children and adolescents in the UK

Authors

  • Yingfen Hsia,

    Corresponding author
    1. Centre for Paediatric Pharmacy Research, The School of Pharmacy, University of London, London, UK
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  • Dalia Dawoud,

    1. Centre for Paediatric Pharmacy Research, The School of Pharmacy, University of London, London, UK
    2. Clinical Pharmacy Department, Faculty of Pharmacy, Cairo University, Cairo, Egypt
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  • Alastair G. Sutcliffe,

    1. UCL Institute of Child Health, University College London, London, UK
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  • Russell M. Viner,

    1. UCL Institute of Child Health, University College London, London, UK
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  • Sanjay Kinra,

    1. Department of Non-communicable Disease Epidemiology, London School of Tropical Medicine and Hygiene, London, UK
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  • Ian C. K. Wong

    1. Centre for Paediatric Pharmacy Research, The School of Pharmacy, University of London, London, UK
    2. UCL Institute of Child Health, University College London, London, UK
    3. Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
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Miss Yingfen Hsia, Centre for Paediatric Pharmacy Research, The School of Pharmacy, University of London, Level 1, BMA/Tavistock House, Tavistock Square, London WC1H 9JP, UK. Tel.: +44 20 7874 1538. Fax: +44 20 7387 5693. E-mail: yingfen.hsia@pharmacy.ac.uk

Abstract

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

• Metformin is licensed for type 2 diabetes mellitus (DM) treatment in the UK.

• Evidence has shown the moderate efficacy of metformin treatment for polycystic ovarian syndrome (PCOS) and obesity.

WHAT THIS STUDY ADDS

• Metformin prescribing increased in children and adolescents between 2000 and 2010, in particular in girls aged 16–18 years.

• PCOS and obesity were the main, but unlicensed, indications for metformin prescribing amongst female adolescents.

AIM

Metformin is the most commonly prescribed oral anti-diabetic drug in young people. It is also prescribed for polycystic ovarian syndrome (PCOS) and obesity treatment in adults in an unlicensed fashion. Little is known as to the extent metformin has been used in young people. We investigated the use of metformin in children and adolescents aged 0–18 years in the UK.

METHODS

Population-based prescribing data were obtained from the UK IMS Disease Analyzer between January 2000 and December 2010.

RESULTS

A total of 2674 metformin prescriptions were issued to 337 patients (80% female) between 2000 and 2010. The prevalence of metformin prescribing increased from 0.03 per 1000 person-years [95% confidence interval (CI) 0.02, 0.05] to 0.16 per 1000 person-years (95% CI 0.12, 0.20) (P= 0.001). There was a steady increase in metformin prescribing in girls aged 16–18 years. There were 290 metformin treated patients (81% female; n= 235) who had at least one diagnosis of diabetes, PCOS or obesity. Among these patients, PCOS was the most common indication for metformin prescribing in girls (n= 120) followed by diabetes. There were 22 patients (7.6%) who received metformin for obesity treatment only.

CONCLUSIONS

Prescribing of metformin increased between 2000 and 2010, in particular amongst girls aged 16–18 years. The main indication for metformin prescribing was PCOS. At present, metformin is not licensed for PCOS and obesity treatment in adults or children. As there is a steady increase in the prescribing of metformin in young people, further studies are required to investigate the efficacy and safety of these prescriptions.

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