POSSIBLE CAUSES FOR OBSERVED VARIATIONS IN ANTIBIOTIC USE

5. POSSIBLE CAUSES FOR OBSERVED VARIATIONS IN ANTIBIOTIC USE

The large variations in antibiotic use in DID or numbers of prescriptions per 1,000 inhabitants and year comparing countries are difficult to explain by medical reasons alone. There is no comprehensive review on guidelines for the treatment of infectious diseases comparing different countries. But differences in antibiotic use may to some extent reflect differences in national guidelines or recommendations, for example, choice of antibiotics, dosage, and length of treatment. In addition, there are different recommendation on antibiotic use for identical indications. For example, antibiotics are recommended for uncompli- cated otitis media in children in most countries but not for children older than

6 months in the Netherlands. In addition, different dosage may explain some of the differences in DID for ␤-lactam antibiotics, since higher dosage may be needed in areas with high prevalence of resistance. But this does not explain the difference in number of prescriptions per 1000 inhabitants, comparing coun- tries, or the large regional differences within countries. In addition, studies show that the number of DIDs, numbers of antibiotic prescriptions, and choice of antibiotic class by general practitioners may differ not only between different countries but also between individual physicians within a country (Huchon et al., 1996; Melander et al., 2000; Örtqvist, 1995; Veninga et al., 2000).

A large part of the differences between countries probably represent irra- tional use of antibiotics. Several non-medical factors may influence the use of antibiotics, for example, differences in healthcare systems (Basky, 1999), antibiotic dosage regimens, patient expectations and attitudes towards taking drugs (Branthwaite and Pechere, 1996; van Duijn et al., 2003), cultural differ- ences (Deschepper et al., 2002), influence of the pharmaceutical industry or over-the counter sales. It has been suggested that the differences in antibiotic usage in Western Europe might be primarily explained by differences in health systems and that a high number of physicians in a country is associated with a high utilisation of antibiotic drugs (Huchon et al., 1996; Veninga et al., 2000). Antibiotics can also, in some countries in Europe, be obtained at pharmacies without a doctor’s prescription, but data on the quantities and qualities of such sales are scarce (Bremon et al., 2000; Contopoulos-Ioannidis et al., 2001).

The available studies on antibiotic use in the community indicate that pre- scribing increased during the 1980s. Highest use in DID was reported from France, Greece, Belgium, and Australia. Highest rate of prescribing was reported from Greece, Spain, and Belgium. In a few countries (United States, Sweden, United Kingdom, and Canada) a decrease in prescribing of antibiotics has been reported after 1995.

Narrow-spectrum penicillin is still the preferred antibiotic in Scandinavian countries and amoxicillin in most other countries. But in most countries there

Antibiotic Use in the Community 579 has been an evident decline in the use of penicillins and a marked increase in the

prescribing of broad-spectrum antibiotics such as macrolides, cephalosporins and quinolones. This general trend, descibed in a review (Carrie and Zhanel, 1999) and also from the Netherlands (Kuyvenhoven et al., 2003), should be of concern to the medical community. Respiratory tract infections are the most common reason for an antibiotic prescription, the majority of which have viral etiology.

Better data are needed to compare antibiotic use in different countries and areas within countries with outcome variables such as resistance, morbidity, and mortality. International cooperation is needed to compare healthcare sys- tems, national guidelines and indications for antibiotic prescribing in different age groups, as well as dosage and treatment duration. The quality of antimi- crobial prescribing in any country, however, cannot be determined by these international comparisons alone. Each country must determine the appropri- ateness of its antimicrobial use and work within its constraints to optimise antimicrobial use.