Inappropriate benzodiazepine use in older adults and the risk of fracture

Authors

  • Cornelis S. Van Der Hooft,

    1. Pharmaco-epidemiology Unit, Department of Epidemiology and Biostatistics, Erasmus University Medical Centre, Rotterdam,
    2. Inspectorate for Health Care, The Hague,
    3. Department of Clinical Geriatrics, Medical Centre Leeuwarden, Leeuwarden and
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  • Mariëtte W. C. J. Schoofs,

    1. Department of Internal Medicine, Erasmus University Medical Centre, Rotterdam, the Netherlands
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  • Gijsbertus Ziere,

    1. Pharmaco-epidemiology Unit, Department of Epidemiology and Biostatistics, Erasmus University Medical Centre, Rotterdam,
    2. Department of Internal Medicine, Erasmus University Medical Centre, Rotterdam, the Netherlands
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  • Albert Hofman,

    1. Pharmaco-epidemiology Unit, Department of Epidemiology and Biostatistics, Erasmus University Medical Centre, Rotterdam,
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  • Huibert A. P. Pols,

    1. Department of Internal Medicine, Erasmus University Medical Centre, Rotterdam, the Netherlands
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  • Miriam C. J. M. Sturkenboom,

    1. Pharmaco-epidemiology Unit, Department of Epidemiology and Biostatistics, Erasmus University Medical Centre, Rotterdam,
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  • Bruno H. Ch. Stricker

    Corresponding author
    1. Pharmaco-epidemiology Unit, Department of Epidemiology and Biostatistics, Erasmus University Medical Centre, Rotterdam,
    2. Inspectorate for Health Care, The Hague,
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  • All authors contributed substantially to its design and performance, and all participated in writing the manuscript.

Dr Bruno H. Ch. Stricker, Department of Epidemiology and Biostatistics, Erasmus Medical Centre, PO Box 1738, 3000 DR Rotterdam, the Netherlands.
Tel: + 31 10 408 8294
Fax: + 31 10 408 9382
E-mail: b.stricker@erasmusmc.nl

Abstract

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

• Benzodiazepine use increases the risk of fracture in the elderly.

• It is controversial which conditions of use are most risky, e.g. use of short- or long-acting benzodiazepines, dose and duration of use.

• The well-known Beers criteria include statements about inappropriate benzodiazepine use in elderly and the risk of fracture, but their clinical value has never been tested in an outcome study.

WHAT THIS STUDY ADDS

• Inappropriate benzodiazepine use according to the Beers criteria is not associated with an increased risk of fracture.

• Daily dose and duration of use is associated with higher risk of fracture, not the type of benzodiazepine prescribed as the Beers criteria state.

AIMS

The Beers criteria for prescribing in elderly are well known and used for many drug utilization studies. We investigated the clinical value of the Beers criteria for benzodiazepine use, notably the association between inappropriate use and risk of fracture.

METHODS

We performed a nested case–control study within the Rotterdam Study, a population-based cohort study in 7983 elderly. The proportion of ‘inappropriate’ benzodiazepine use according to the Beers criteria was compared between fracture patients and controls. ‘Inappropriate’ use for elderly implies use of some long-acting benzodiazepines and some intermediate/short-acting ones exceeding a suggested maximum daily dose. Also, alternative criteria were applied to compare the risk of fracture. Cases were defined as persons with incident fracture between 1991 and 2002 who were current benzodiazepine users on the fracture date. Controls were matched on fracture date and were also current benzodiazepine users.

RESULTS

The risk of fracture in ‘inappropriate’ benzodiazepine users according to the Beers criteria was not significantly different from ‘appropriate’ users [odds ratio (OR) 1.07, 95% confidence interval (CI) 0.72, 1.60]. However, a significantly higher risk of fracture was found in ‘high dose’ users and a longer duration of use (14–90 days), irrespective of the type of benzodiazepine (OR 3.45, 95% CI 1.38, 8.59).

CONCLUSIONS

These findings suggest that inappropriate benzodiazepine use according to the Beers criteria is not associated with increased risk of fracture. Daily dose and longer duration of use (>14 days) is associated with higher risk of fracture, irrespective of the type of benzodiazepine prescribed.

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