Geographic and Temporal Variations in Community Antibiotic Use, Florida, 2010-2012

Background: Antimicrobial resistance is a worldwide problem posing a serious threat to human health, with an estimated two million illnesses and 23,000 deaths in the US alone. Antibiotic use is the most important contributing factor to the development of antibiotic resistance; half of all antibiotics prescribed are unwarranted or improperly prescribed.  

Methods: To understand trends in antibiotic prescribing, we conducted a temporospatial analysis of 24 months of community antibiotic prescription data in Florida obtained from IMS Health Xponent database, which represent 100% projection of all outpatient prescription activity. We conducted a spatial regression of healthcare and demographic factors on county-level antibiotic prescriptions using ArcGIS and SaTScan. 

Results: Between 2010 and 2012, an average 15 million antibiotic prescriptions were prescribed in Florida annually, equating to 0.81 prescriptions per person.  We observed the highest prescription rates for B-lactam antibiotics; however, prescribing patterns varied across Florida counties by healthcare provider composition and demographics.  Children aged 1-4 years old received the greatest proportion of antibiotics and general practitioners were the highest prescribers. B-lactams, macrolides, cephalosporins, and fluoroquinolones demonstrated seasonality, while tetracycline and trimethoprim-sulfamethoxazole did not.  Among those demonstrating seasonality, prescriptions peaked in winter months, coinciding with seasonal peaks in the incidence of viral respiratory infections. 

Conclusions: These data demonstrate variations in healthcare provider prescribing practices and highlight communities as well as provider groups in which direct public health messaging should be aimed.  Understanding current trends in community antibiotic use may lead to targeted public health messaging aimed at high-prescribing provider groups or high-consuming patient populations.