RESEARCH ARTICLE Prevalence of inappropriate prescribing in primary care Lisbeth Bregnhøj Æ Steffen Thirstrup Æ Mogens Brandt Kristensen Æ Lars Bjerrum Æ Jesper Sonne Received: 17 January 2005 / Accepted: 19 October 2005 / Published online: 13 March 2007 ª Springer Science+Business Media B.V. 2007 Abstract Objective: To describe the prevalence of inappropriate prescribing in primary care in Copenhagen County, according to the Medication Appropriateness Index (MAI) and to identify the therapeutic areas most commonly involved. Setting: A cross-sectional study was conducted among 212 elderly (>65 years) polypharmacy patients (five or more different medications) listed to 41 general practi- tioners (GPs) in the County of Copenhagen. Method: Patients exposed to polypharmacy were iden- tified via the database recording the drug subsidy system of Danish pharmacies. For each patient, data were col- lected on subsidised medications prescribed over 3 months by the patients’ own GPs. The GPs were asked to provide baseline information regarding the patients’ medical history and detailed information regarding the subsidised and non-subsidised medications prescribed to the patients. A MAI was scored for medication pre- scribed to the patients. Topical, dermatological medi- cations and medications not used regularly were excluded. Results: 212 patients were prescribed 1621 medications by their GPs at baseline. In all, 640 (39.5%) of the medications had one or more inappropriate ratings in the 10 criteria making up the MAI. The main part of the patients (94.3%) had one or more inappropriate ratings among their medications. A total of 12.3% of the medications were rated as Ônot indicated’, 6% were rated as Ôineffective’, 6.7% were given in an incorrect dose, 0.7% were prescribed with incorrect directions, 1.3% had impractical directions, 0.7% of the drugs had clin- ically significant drug–drug interactions, 8.6% had clinically significant drug–disease/condition interac- tions, 3.1% were unnecessary duplications, 16.5% were given in an unacceptable duration and 27.1% of the medications were not the least expensive alternative. The therapeutic groups most commonly involved in inappropriate prescribing were medications for treat- ment of peptic ulcer, cardiovascular medications, anti- inflammatory medications, antidepressants, hypnotics and anti-asthmatics. Conclusion: The overall prescribing quality in primary care in Copenhagen County, Denmark is good. However, the majority of patients used one or more medications with inappropriate ratings. The inappro- priate prescribing relates to specific therapeutic groups and criteria, which should be targeted in future interventions. Keywords Denmark Æ Elderly Æ General practice Æ Medication Appropriateness Index Æ Polypharmacy Æ Prescribing quality Æ Prevalence Introduction Inappropriate prescribing is a common problem among elderly patients and causes many preventable adverse events and treatment failures. The prevalence of inap- propriate prescribing is, however, difficult to assess due to lack of standards for good and poor prescribing quality, publication bias, etc. [1]. When explicit criteria, which specifies medications or dosages to be avoided, for instance the widely used Beers criteria [2, 3], have been applied to define inappropriate prescribing, 21.3–40% of patients in various settings have been shown to receive at least one inappropriate medication [4]. The alternative, implicit medication reviews, which L. Bregnhøj (&) Æ J. Sonne Clinical Pharmacology Unit, Gentofte University Hospital, 4022, Niels Andersensvej 65, 2900, Hellerup, Denmark E-mail: libregn@tiscali.dk S. Thirstrup Æ M. B. Kristensen The Danish Medicines Agency, Axel Heides Gade 1, 2300, Copenhagen S, Denmark L. Bjerrum Research Unit of General Practice, University of Southern Denmark, JB Winsløwsvej 9, 5000, Odense C, Denmark Pharm World Sci (2007) 29:109–115 DOI 10.1007/s11096-007-9108-0 123