Antibiotic consumption trends among acute care hospitals in Catalonia (2008-2016): impact of different adjustments on the results

Abstract

Objectives: Hospital antibiotic consumption is measured using defined-daily-doses (DDD) divided by bed days. However,other denominators as discharges could provide a more accurate interpretation of consumption. The main objective was to analyze trends of antibiotic consumption among hospitals in Catalonia during the period 2008-2016, using both DDD/100 bed days and DDD/100 discharges.

Methods: Retrospective, descriptive, and longitudinal study performed among acute care hospitals affiliated to VINCat Program. Antibiotic consumption was expressed using the Anatomical Therapeutic Chemical/DDD classification and trends with a mixed linear model. Trends after using both DDD/100 bed days and DDD/100 discharges were determined and compared.

Results: Overall antibiotic consumption from 2008 to 2016 increased by 10.24% (P < 0.001) DDD/100 bed days, but remained stable (-0.87%, P = 0.051) in DDD/100 discharges. Although DDD and discharges remained unchanged, a significant reduction in bed days (-9.63%) and length of stay (-8.19%) was observed. A worrisome increase in the consumption of carbapenems and anti-MRSA drugs was noticed.

Conclusion: Whereas a significant upward trend in antibiotic consumption in DDD/100 bed days was noticed, DDD/100 discharges remained stable. The description of both indicators seems therefore essential for a correct interpretation of data.

Keywords: Antimicrobial stewardship; antibiotic consumption; carbapenems; defined daily dose; discharges; patient-days.