Quantitative disparities in outpatient antibiotic exposure in a Hungarian county

Although antibiotic utilization data expressed in defined daily doses (DDDs)/1000 inhabitants/day are often available for a given period and area, the actual antibiotic exposure of the population is rarely explored. We aimed to identify the real antibiotic exposure of the inhabitants of one Hungarian county. The patient-level dispensing data for 2005 for Csongrad County were retrieved from the database of the Hungarian National Health Fund Administration. The number of antibiotic users was quantified, and differences in antibiotic use (quantity and frequency) were explored. Disparities were revealed by Lorenz curves. A new form of Lorenz curve was also introduced. The DDD values for 2005 were used. In 2005, a total of 486 115 antibiotic prescriptions were redeemed, and 3 329 385 DDDs were dispensed to 213 748 different patients; 50.3% of the inhabitants of Csongrad County (total population 424 615) took antibiotics. The average consumption of 1-, 2-, 3-, 4- and 5-time users was 7.5, 14.6, 21.0, 26.9 and 32.2 DDDs per user, respectively. Lorenz curves (including the new form of Lorenz curve) demonstrated the existence of disparities in antibiotic use. One percent of the users with the heaviest consumption were responsible for 6.9% of the total use and redeemed antibiotic prescriptions nine times or more during 2005. Disparities in antibiotic use were detected: half of the inhabitants were exposed to antibiotics, and among antibiotic users, the quantity of antibiotics that they redeemed displayed great variance, mainly due to differences in the prescribing frequency. Special attention should be paid to those with frequent antibiotic use (five times or more annually).