Eur J Clin Pharmacol (2005) 61: 893–897 DOI 10.1007/s00228-005-0031-9 PHARMACOEPIDEMIOLOGY AND PRESCRIPTION Péter Doró . Ria Benkő . Edit Kosik . Mária Matuz . Katalin Tóth . Gyöngyvér Soós Utilization of oral antihyperglycemic drugs over a 7–year period (1998–2004) in a Hungarian population and adherence to drug therapy Received: 28 April 2005 / Accepted: 24 August 2005 / Published online: 17 November 2005 # Springer-Verlag 2005 Abstract Objective: To describe the quantitative and qualitative changes in the utilization of oral antihypergly- cemic drugs (OAHDs) between 1998 and 2004 and to analyze patients’ adherence to OAHD therapy. Methods: We conducted a retrospective analysis of the electronic data- base of the Hungarian National Health Fund Adminis- tration for the years 1998 through 2004. All 912,620 prescriptions for OAHDs dispensed for the 38,855 patients in Csongrád County (430,000 inhabitants) were retrieved and analyzed according to the ATC/DDD (World Health Organization) methodology. Nonadherence was set as medication possession ratio <80%. Results: The number of patients using OAHDs significantly increased (P<0.001); the yearly prevalence of 2.88% in 1998 increased to 4.32% in 2004. The overall consumption of OAHDs increased by 76%, from 20.85 defined daily doses per 1,000 inhabitants per day (DDD/TID) in 1998 to 36.83 DDD/TID in 2004. While in 1998 glibenclamide was the most often prescribed agent, received by 61.7% of patients, its share dropped to 16.1% in 2004, and metformin became the leading agent prescribed for 43.0% of patients. During the study period, the adherence rate varied between 47.9% and 49.2%. Women had a significantly better (P<0.001) adherence rate than men, 51.3% vs. 45.5%. The adherence rate peaked in patients between 60 and 79 years and was lowest in patients in their 30s. Conclusions: The utilization pattern of OAHDs considerably changed, but there were no sig- nificant changes in patients’ adherence. The significant in- crease in the utilization of OAHDs is not the result of increased adherence but of increased patient number. Keywords Diabetes mellitus . Oral antihyperglycemic drugs . Drug utilization . Adherence Introduction As a result of an aging population, changes in lifestyle, and higher levels of obesity, diabetes affects an increasing number of patients, and the number is expected to more than double worldwide by the year 2030 [1]. The estimated prevalence of diabetes among adults was 9.7% in Hungary in 2003, which was among the highest values in Europe [2]. An increased blood glucose level is associated with a greater risk of microvascular and macrovascular complica- tions. It has been reported that macroangiopathy can effect up to one-third of patients diagnosed with type 2 diabetes [3]. These complications not only diminish the health of the patients and may disable them but also put a high financial burden on the healthcare system. The United Kingdom Prospective Diabetes Study clearly proved the benefits of intensive glycemic control in patients with type 2 diabetes [4]. Previous studies have shown that increased adherence to oral antihyperglycemic drugs (OAHDs) results in better metabolic control and, consequently, in decreased hospi- talization rates and lowered total annual healthcare costs [5–7]. A systematic review of 20 reports showed that ad- herence to OAHD therapy varied widely, ranging from 36% to 93% [8]. The aim of this study was to describe the changes in the utilization of OAHDs in Csongrád County, Hungary, and to perform a population-based estimation of patient adherence to OAHD therapies. Subjects and methods All 912,620 prescriptions for OAHDs dispensed for the 38,855 patients in Csongrád County were retrieved from the prescription drug claims database of the Hungarian National Health Fund Administration (HNHFA) for 1998 through 2004. Csongrád County is one of 20 Hungarian P. Doró (*) . R. Benkő . E. Kosik . M. Matuz . K. Tóth . G. Soós Department of Clinical Pharmacy, University of Szeged, Szikra u.8., H-6725 Szeged, Hungary e-mail: dorop@clph.szote.u-szeged.hu Tel.: +36-62-544921 Fax: +36-62-544921