January 30, 2019
Antibiotic use among patients hospitalized for asthma exacerbations may lead to longer hospital stays and increased cost, with no reduction in the risk for treatment failure, according to a study published online January 28 in JAMA Internal Medicine.
"These findings are novel, reflect the experience of unselected patients cared for in routine settings, and lend strong support to current guidelines that recommend against the use of antibiotics in the absence of concomitant infection," write Mihaela S. Stefan, MD, PhD, from the University of Massachusetts Medical School, Springfield, and colleagues.
As part of a retrospective cohort study, the researchers evaluated data from 19,811 patients (median age, 46 years) hospitalized for an asthma exacerbation and treated with corticosteroids from January 1, 2015, through December 31, 2016. Patient data were obtained from 543 small to medium acute care hospitals across the United States. Patients for whom antibiotic therapy may have been indicated were excluded.
Stefan and colleagues found that 8788 patients (44%) were treated with antibiotics during the first 2 days of hospitalization. Compared with those not treated with antibiotics, patients given antibiotics were slightly older (median age, 48 years), more likely to have Medicare insurance, more likely to be smokers, and more likely to have been diagnosed with acute respiratory failure or a comorbid condition (eg, congestive heart failure, chronic pulmonary disease, diabetes).
The researchers matched 6833 patients who received early antibiotic therapy with similar patients who did not received early antibiotic intervention. They found that the rate of treatment failure was comparable between the two groups (5.5% vs 5.7%; P = .58). Treatment failure was defined as "initiation of invasive or noninvasive mechanical ventilation, transfer to the intensive care unit after hospital day 2, in-hospital mortality, or readmission or asthma exacerbation within 30 days of discharge."
In addition, among the matched cohort, the median length of hospital stay in the antibiotic therapy group was 4 days (interquartile range [IQR], 3 to 5 days) compared with 3 days (IQR, 2 to 4 days; P < .001) among those who did not receive antibiotics.
Antibiotic intervention was also associated with a higher cost of hospitalization (median cost with antibiotic intervention, $4776; IQR, $3219 – $7373; median cost without antibiotic intervention, $3641; IQR, $3246 – $5942).
The authors acknowledge the potential for confounding by indication "in which antibiotics would be preferentially given to patients with higher acuity of illness," but note that the use of instrumental variable analysis and multiple sensitivity analyses helped control for this risk. Given the observational nature of the study, the authors note that these results demonstrate an association between length of hospital stay and antibiotic use but cannot prove causality.
"Our results support current clinical guidelines that recommend against the use of antibiotics in the treatment of patients with asthma exacerbation" and "highlight the need for future research to improve antimicrobial stewardship in the setting of asthma," Stefan and colleagues conclude.
The authors' relevant financial relationships are listed in the original article.