Women living in rural areas were significantly more likely than were those in urban areas to receive inappropriate antibiotic prescriptions for urinary tract infections, based on data from an observational cohort study of more than 600,000 women.
Uncomplicated urinary tract infections (UTIs) are common among otherwise healthy women in the United States, and certain antibiotics are recommended as first-line therapy, wrote Abbye W. Clark, MD, of Washington University, St. Louis, and colleagues.
“However, the majority of antibiotic prescriptions for uncomplicated UTI are suboptimal because they are written for nonrecommended agents and durations,” they said.
Addressing rural health disparities has become a focus in the United States, and previous studies of respiratory tract infections have shown differences in antibiotic prescribing based on geographic region; “however, no large-scale studies have evaluated rural-urban differences in inappropriate outpatient prescribing for UTI,” they added.
In a study published in Infection Control & Hospital Epidemiology, the researchers identified 670,450 women aged 18-44 years who received oral antibiotics for uncomplicated UTIs between 2010 to 2015, using a commercial insurance database to determine diagnosis and antibiotic prescription information. Women were defined as urban if they lived in a metropolitan statistical area of at least 50,000 inhabitants (86.2%); all other women were defined as rural (13.8%). The median age was 30 years for both groups.
Overall, 46.7% of the women received prescriptions for inappropriate antibiotics, and 76.1% received antibiotics for inappropriate durations.
Antibiotics and durations were defined as appropriate or inappropriate based on current clinical guidelines. “We classified first-line agents (nitrofurantoin, TMP-SMX, fosfomycin) as appropriate and non–first-line agents (fluoroquinolones, beta-lactams) as inappropriate,” the researchers said.
The regimens classified as appropriate duration were “nitrofurantoin 5-day regimen, TMP-SMX (including TMP monotherapy) 3-day regimen, fosfomycin 1-day regimen, fluoroquinolones 3-day regimen, and beta-lactams 3- to 7-day regimen. All other regimens were classified as inappropriate duration,” they noted.
More rural women receive long-duration antibiotics
In a multivariate analysis, similar percentages of antibiotics for rural and urban women consisted of inappropriate agents (45.9% vs. 46.9%) including use of fluoroquinolones (41.0% vs. 41.7%) and beta-lactams (4.8% vs. 5.0%).
However, across all antibiotics, women in rural areas were more likely than were women in urban areas to receive prescriptions for inappropriately long durations (83.9% vs. 75.9%, adjusted risk ratio 1.10).
The percentage of women who received inappropriate antibiotic agents was not significantly different based on geographic region of the country.
From 2011 to 2015, the quarterly proportion of women overall who received inappropriate agents and antibiotics for inappropriate durations decreased slightly (48.5% to 43.7% and 78.3% to 73.4%, respectively), the researchers noted.
The study findings were limited by several factors including the potentially lenient definition of antibiotic duration, a study population that disproportionately oversampled from the South and undersampled from the West, use of ZIP codes to determine rural vs. urban status, lack of data on race and income, and lack of access to urine culture results, the researchers noted.
However, “our study identified rural-urban differences in antibiotic prescribing, including an actionable disparity in the duration of antibiotics that disproportionately affects women who live in rural locations,” they said.
“Given the large quantity of inappropriate prescriptions annually in the U.S., as well as the negative patient- and society-level consequences of unnecessary exposure to antibiotics, antimicrobial stewardship interventions are needed to improve outpatient UTI antibiotic prescribing, particularly in rural settings,” they concluded.