Antibiotics Linked To Increased Hospital Stay for Exacerbated Asthmatics

Mihaela S. Stefan, MD, PhD

More evidence indicates that antibiotic therapy may actually be counterintuitive to the care of hospitalized asthmatics suffering from exacerbations.

In a new study from investigators at the Institute for Healthcare Delivery and Population Science, University of Massachusetts Medical School, antibiotic treatment was found to have an association with greater lengths of hospital stay—and therefore costs—in patients hospitalized for an asthma exacerbation previously treated with systemic corticosteroids.

The retrospective cohort analysis, led by Mihaela S. Stefan, MD, PhD, sought to complement recent reviews and guidelines advising against routine antibiotic prescription to patients hospitalized with asthma exacerbation. The review is a pressing one—a recent large national sample reported that nearly half (49.1%) of all such hospitalized patients with asthma received antibiotics without documentation indicating them for antibiotic therapy, Stefan and colleagues noted.

Whether it’s actually beneficial for the patient has been questioned, though.

“In the absence of more definitive information from randomized clinical trials, we sought to evaluate the association between use of antibiotics when prescribed in addition to corticosteroids and outcomes among a large, representative sample of patients hospitalized for asthma exacerbation,” investigators wrote.

The team collected data from 543 US acute care hospitals that also participate in the Premier Inpatient Database. Qualified patients for assessment were 18 years or older who had been admitted to the hospital for a principal diagnosis of asthma or acute respiratory failure combined with secondary asthma diagnosis, at any time between 2015 and 2016.

Investigators identified 19,811 patients, with a median age of 46 (34-59) years. A majority (72.6%) were female, 44.3% were white, and 25.8% of patients used Medicare as their primary form of insurance. Among all patients, the most common comorbidities were hypertension (45%), obesity (28.8%), diabetes (22.5%), and depression (12.9%).

Similar to the previous study, nearly half (44.4%) of all patients received antibiotics within their first 2 days in the hospital—primarily prescribed macrolides (51.9%), quinolones (34.8%), and third-generation cephalosporins (19.6%). Just 3% of all patients received antibiotics beyond their second day of stay.

Among patients prescribed antibiotics, the population consisted of a greater rate of white patients (48.9%) and smokers (6.6%). Antibiotic-treated patients were also more likely to have a greater rate of comorbidities, including heart failure (6.2% vs 5.8%).

Treated patients were found to have a significantly longer hospital stay (median interquartile range [IQR] 4 [3-5] vs 3 [2-4] days), despite a similar rate of treatment failure to patients not given antibiotics (5.4% vs 5.8%). In assessing with propensity score matching, antibiotics were associated with a 29% greater length of hospital stay (ratio 1.29; 95% CI: 1.27-1.31), and a median hospitalization cost difference of more than $1100 ($4776 vs $3641), without difference in risk of treatment failure.

Investigators concluded these findings were novel, and indicative of current guideline’s necessity to reinforce their advisory against antibiotic prescription in the absence of concomitant infection. The findings also give perspective to the experience of unselected patients care for in a routine hospital setting, and emphasize the need for further research to direct the stewardship of antibiotic use in the asthma field.

“Inappropriate use of antibiotics is a public health problem given the risk of bacterial resistance and of antibiotic-related adverse events,” investigators wrote. “The discontinuation of ineffective, overused, or harmful interventions, or de-implementation, has emerged as a new area of inquiry in the field of dissemination and implementation science.”

Stefan and colleagues also advise that clinicians validate known biomarkers in patients with asthma, such as procalcitonin levels, for guiding targeted antibiotic therapy—as evidenced by 2 recent China-based studies that showed the practice resulted in no difference in hospital length of stay, asthma exacerbations, or readmissions.

“Further research is needed to develop and test de-implementation strategies to reduce inappropriate antibiotic prescribing for patients hospitalized for asthma,” they concluded.

The study, "Association of Antibiotic Treatment With Outcomes in Patients Hospitalized for an Asthma Exacerbation Treated With Systemic Corticosteroids," was published online in JAMA.