Misuse of antibiotics, including antibiotic overuse and inappropriate antibiotic selection, is common in the treatment of outpatient acute respiratory infections (ARIs), according to the results of a study published in JAMA Network Open.
ARIs are the most common reason for antibiotic prescription, but most of these illnesses are caused by viral pathogens, for which antibiotics offer no benefit. Inappropriate use of antibiotics is a major driver of antibiotic resistance in bacteria. These resistant pathogens cause 2 million illnesses and 23,000 deaths annually in the United States. Prior studies investigating antibiotic misuse have relied on national survey data and therefore often lack clinical and laboratory testing results.
Fiona P. Havers, MD, of the US Centers for Disease Control and Prevention, and colleagues conducted a cohort study that enrolled patients aged 6 months or older with an ARI who were evaluated at outpatient clinics associated with five US Influenza Vaccine Effectiveness Network sites during the 2013-2014 and 2014-2015 influenza seasons. The investigators included data on illness onset date, results of laboratory testing for influenza in all patients, and for many patients, self-reported fever and results of group A streptococcal (GAS) testing. They also collected data on antibiotic prescriptions, medical history, and International Classification of Diseases-9th edition, codes from medical and pharmacy records.
The study included 14,987 patients with an ARI. Antibiotics were prescribed in 41% of these patients, and of those, 41% received an antibiotic for a non-indicated diagnosis. Of the 3306 patients (22%) who had confirmed influenza without pneumonia, 29% received an antibiotic prescription. Among the 1248 patients with pharyngitis, 91% had GAS testing. A total of 35% of patients with pharyngitis were prescribed antibiotics, and of those, 38% had negative GAS testing results. A total of 1200 patients with sinusitis and no other symptoms suggesting a bacterial illness received an antibiotic; 38% of these had symptoms for 3 days or fewer before the outpatient visit, indicating an acute viral infection.
The study has a number of limitations. The investigators used up to 4 International Classification of Diseases-9th edition codes to establish whether antibiotics were prescribed appropriately, but the codes may have been inaccurate. Medical history information may have been incomplete for some patients, and other reasons may have been involved in the decision to prescribe. The selected study sites may not have been representative of other outpatient settings.
The authors noted that the National Action Plan for Combating Antibiotic-Resistant Bacteria has a goal of reducing inappropriate outpatient antibiotic use by 50% by 2020. They argued that outpatient antibiotic stewardship efforts must be strengthened to eliminate antibiotic treatment for viral upper respiratory infections and acute bronchitis, which this study indicates would contribute the most to decreasing unnecessary use of these agents. Additionally, they called for increased efforts to improve adherence to antibiotic prescribing guidelines.
Disclosures: Several authors report financial relationships with MedImmune/AstraZeneca, Merck, Sanofi Pasteur, Novartis, Pfizer, and Roche.
Havers FP, Hicks LA, Chung JR, et al. Outpatient antibiotic prescribing for acute respiratory infections during influenza seasons. JAMA Network Open. 2018;1(2):e180243.