An analysis of data from US ambulatory care facilities found that roughly 13% of visits for acute gastroenteritis (AGE) resulted in a prescription for an antibiotic, with antibiotics more frequently prescribed in doctors' offices and urgent care clinics, researchers with the Centers for Disease Control and Prevention (CDC) reported today in Infection Control & Hospital Epidemiology.
Fluoroquinolones most often prescribed
Using data from the National Ambulatory Medical Care Survey and the National Hospital Ambulatory Medical Care Survey (NAMCS/NHAMCS) for 2006 through 2015, along with 2014 data from the IBM MarketScan Commercial Claims and Encounters database, CDC researchers calculated the percentage of visits for viral and bacterial AGE infections that received an antibiotic.
Roughly 75 million diarrheal illnesses a year result in visits to US ambulatory care facilities, but national antibiotic prescribing rates for AGE have not been well described.
Analysis of 10,210 NAMCS/NHAMCS visits for AGE found that 13.3% (99% confidence interval [CI], 11.2% to 15.4%) resulted in an antibiotic prescription, most frequently for fluoroquinolones (28.7%; 99% CI, 21.1% to 36.3%), followed by nitroimidazoles (20.2%; 99% CI, 14.0% to 26.4%) and penicillins (18.9%; 99% CI, 11.6% to 26.2%). Antibiotic prescribing was most frequent in patients aged 18 to 49 years (16.6%; 99% CI, 12.6% to 20.6%) and more frequent in office settings (15.7%; 99% CI, 11.8% to 19.7%) than emergency departments (10.8%; 99% CI, 9.5% to 12.1%).
Among 1,868,465 MarketScan AGE visits, antibiotics were prescribed for 13.8% (95% CI, 13.7% to 13.8%), most frequently in urgent care centers (18.6%; 95% CI, 18.3% to 18.9%), followed by office settings (14.8%; 95% CI, 14.7% to 14.9%) and emergency departments (11.2%; 95% CI, 11.2% to 11.3%).
Antibiotics were most commonly prescribed for Yersinia (46.7%; 95% CI, 21.4% to 71.9%), Campylobacter (44.8%; 95% CI, 41.5% to 48.1%), Shigella (39.7%; 95% CI, 35.9% to 43.6%), typhoid or paratyphoid fever (32.7%; 95% CI, 27.2% to 38.3%), and nontyphoidal Salmonella (31.7%; 95% CI, 29.5% to 33.9%).
Analysis of the MarketScan data also showed that antibiotics were inappropriately prescribed for 12.3% (95% CI, 11.7% to 13.0%) of visits for viral AGE and 21% of AGE cases caused by Shiga toxin–producing Escherichia coli. The researchers also identified antibiotic prescribing patterns that were inconsistent with 2017 guidelines from the Infectious Diseases Society of America.
Lower emergency department use a surprise
The study authors say the lower rate of antibiotic prescribing in emergency departments is a surprise, since AGE patients who go to emergency departments tend have more acute illness than those who seek care at doctors' offices or urgent care. They say the findings "underscore the need for antibiotic stewardship assessments and interventions in for AGE in ambulatory settings."
"Although antibiotic stewardship efforts have been successful in hospital settings and for viral respiratory infections, more work is needed for AGE in outpatient settings," they wrote. "Providers in medical offices and urgent-care centers may especially benefit from further evaluation of antibiotic prescribing practices and antibiotic stewardship related to AGE."
The authors also say that public health messaging for patients should emphasize that most diarrheal illnesses do not require antibiotics.