Background
Little is known about the clinical and financial consequences of inappropriate antibiotics. We aimed to estimate the comparative risk of adverse drug events and attributable health care expenditures associated with inappropriate versus appropriate antibiotic prescriptions for common respiratory infections.
Methods
We established a cohort of adults 18–64 years with an outpatient diagnosis of a bacterial (pharyngitis, sinusitis) or viral respiratory infection (influenza, viral URI, non-suppurative otitis media (OM), bronchitis) from April 1, 2016 to September 30, 2018 using Merative™ MarketScan® Commercial Database. The exposure was an inappropriate versus appropriate oral antibiotic (i.e., non-guideline-recommended versus guideline-recommended antibiotic for bacterial infections; any versus no antibiotic for viral infections). Propensity score-weighted Cox proportional hazards models were used to estimate the association between inappropriate antibiotics and adverse drug events. Two-part models were used to calculate 30-day all-cause attributable health care expenditures by infection type.
Results
Among 3,294,598 eligible adults, 43%–56% received inappropriate antibiotics for bacterial and 7%–66% for viral infections. Inappropriate antibiotics were associated with increased risk of several adverse drug events, including Clostridioides difficile infection and nausea/vomiting/abdominal pain (HR, 2.90; 95% CI, 1.31–6.41 and HR, 1.10; 95% CI, 1.03–1.18, respectively, for pharyngitis). Thirty-day attributable health care expenditures were higher among adults who received inappropriate antibiotics for bacterial infections ($18–$67) and variable (-$53–$49) for viral infections.
Conclusions
Inappropriate antibiotic prescriptions for respiratory infections were associated with increased risks of patient harm and higher health care expenditures, justifying a further call-to-action to implement outpatient antibiotic stewardship programs.