Patients with febrile respiratory illness who presented during an influenza pandemic were less likely to receive antibiotics than those presenting with similar symptoms during a regular ﬂu season, researchers found.
In a retrospective study, antibiotic prescribing was significantly lower during the H1N1 influenza pandemic than during nonpandemic seasons (OR 0.72, 95% CI 0.68 to 0.77), Courtney Hebert, MD, of Ohio State University in Columbus, and colleagues reported in the August 7 issue of the Annals of Internal Medicine.
Thus, providing an epidemiologic context may help reduce overprescribing of antibiotics for these patients, the researchers wrote, although they cautioned that the study design prevented definitive conclusions about causality.
Antibiotics are not useful for treating viral respiratory infections, and their overuse can lead to antibiotic resistance in the community. Yet they're often prescribed because the possibility of bacterial infection is seldom ruled out.
Indeed, there are few bedside cues for distinguishing between viral and bacterial respiratory illnesses. But having contextual clinical cues could help reduce antibiotic use, Hebert and colleagues wrote.
So they conducted a retrospective cohort study among a network of Midwestern primary care providers, looking at all patients who had a febrile respiratory illness during flu seasons between 2006 and 2011. They looked specifically at whether the epidemiologic context created by the H1N1 pandemic -- from April to June 2009 and again from September 2009 to March 2010 -- had any effect on the use of antibiotics for those illnesses.
A total of 28,301 patients were seen by 69 physicians in 26 practices over a median follow up of 5.5 years.
Overall, an antibiotic was prescribed in 45.2% of cases, with a range among clinicians of 17.9% to 83.7%, which was "surprising that it comes from a group based in the same region," the researchers noted.
They found that antibiotics were prescribed less frequently during the H1N1 pandemic than during the regular flu seasons (39.2% versus 47.5%, P>0.001), and that context proved a strong independent predictor of antibiotic prescribing, with a significantly lower likelihood of clinicians recommending antibiotics during the pandemic (OR 0.72, 95% CI 0.68 to 0.77).
Greater clinician awareness, along with greater patient awareness, of the possibility of viral illness likely played a role in diminished antibiotic prescribing, the researchers wrote.
They also observed a simultaneous jump in prescriptions for antivirals, with 12.6% of febrile respiratory illness patients prescribed one during the pandemic compared with 5.5% during seasonal flu (OR 6.43, 95% CI 5.02 to 8.25). These scripts could have been a substitute for antibiotics, the researchers said.
Hebert and colleagues noted, however, that a physician's personal context was also associated with antibiotic prescribing. During both seasonal and pandemic flu, the likelihood of writing an antibiotic script fell as the number of respiratory illness cases a physician saw increased:
- OR 0.84 (95% CI 0.77 to 0.91) for 4 to 6 patients in the previous week
- OR 0.71 (95% CI 0.64 to 0.78) for 7 to 11 patients
- OR 0.57 (95% CI 0.51 to 0.63) for 12 or more patients
Antiviral prescribing went in the opposite direction based on number of patients with respiratory illness seen in the previous week -- increasing for those who had seen more than 12 patients, which suggests that "regardless of what physicians know from outside sources, recent personal experience still influences them," the researchers wrote.
This study was limited by being nonrandomized and restrospective research done in a single area. Also, "a potential impediment to concluding that prescribing was affected by context was the possibility that [febrile respiratory illness] cases differed in their clinical features from one period to the other," the authors explained.
The journal editors also pointed out that the study included relatively few elderly patients and was done only during flu season.
Nonetheless, "tools that increase physician awareness of context may help to drive much-needed improvements in prescribing," the authors concluded.
The study was supported by grants from NorthShore University HealthSystem Research.
The researchers reported no conflicts of interest.
- Reviewed by Dori F. Zaleznik, MD Associate Clinical Professor of Medicine, Harvard Medical School, Boston and Dorothy Caputo, MA, BSN, RN, Nurse Planner
Annals of Internal MedicineSource Reference: Hebert C, et al "The influence of context on antimicrobial prescribing for febrile respiratory illness" Ann Intern Med 2012; 157(3):160-169.