Can a patient information sheet reduce antibiotic use in adult outpatients with acute bronchitis? - Patient-Oriented Evidence that Matters

Journal of Family Practice, April, 2002 by Michael DeBisschop, Beth Robitaille

Macfarlane J, Holmes W, Gard P, et al. Reducing antibiotic use for acute bronchitis in primary care: blinded, randomised controlled trial of patient information leaflet. BMJ 2002; 324:1-6.

* BACKGROUND Inappropriate use of antibiotics for acute bronchitis can contribute to the growing incidence of bacterial resistance in the community. Although the majority of acute bronchitis cases are viral, patient expectations that antibiotics are required to treat this illness result in frequent prescribing of these drugs. This study investigates the use of written patient education regarding the role of antibiotics for acute bronchitis in an attempt to decrease antibiotic use.

* POPULATION STUDIED The researchers recruited 259 patients aged 16 years and older with acute bronchitis from 3 general practices in Nottingham, England. Patients were required to have acute cough and at least 1 other respiratory tract symptom. Patients were excluded with asthma, chronic obstructive pulmonary disease, heart disease, and diabetes. The median age was 44 years; 26% of patients were smokers; and 80% had a clear chest exam.

* STUDY DESIGN AND VALIDITY The patients' individual physicians used their clinical judgment to divide the patients into 2 groups: those who definitely needed antibiotics and those who did not definitely need antibiotics. Patients in the first group did not participate in the study. Patients in the second group were randomized to receive either a blank sheet of paper or a patient information sheet explaining the natural history of acute bronchitis and discouraging the use of antibiotics (available at http://bmj.com/cgi/content/full/324/7329/91/F1). The physician, who was blinded to randomization, distributed the study sheet in a sealed envelope at the office visit; patients were asked to open the envelope after the visit.

Each patient also received an antibiotic prescription. The patients were counseled by the physician that they were "quite likely not to need" the antibiotic, but to use their judgment and consider taking the antibiotic "if you feel you are getting worse." Blinded investigators contacted the patients at 1 and 2 weeks post visit to determine antibiotic use. Two patients who received information sheets and 5 in the control group were lost to follow-up; these patients were not included in the results analysis.

This study's allocation concealment, randomization, and single-blinding procedures appear adequate. However, the researchers relied primarily on the physicians' clinical judgment to determine which patients to include in the trial. While this method admirably attempts to reflect real-world primary care practice, it may adversely affect the study's external validity, since we aren't sure how the physicians ultimately selected the patients to include in the randomized trial. Also, since the physician verbally counseled each patient in both groups that they probably would not need the antibiotic, the study probably underestimates the true effect of the information sheet.

* OUTCOMES MEASURED The primary endpoint in this study was whether the patient took the prescribed antibiotic. The secondary endpoint was the number of patients requiring a second office visit within a month for the same illness. Other patient-oriented outcomes such as patient satisfaction, number of sick days, and severity of illness were not directly measured, although the authors state that the rate of patient follow-up is a surrogate measure for these outcomes.

* RESULTS Of the 259 eligible patients, 212 entered the randomized trial. Forty-nine (47%) patients who received the information sheet took their antibiotics compared with 63 (62%) control patients (relative risk, 0.7; 95% CI, 0.59-0.97; P = .04). One additional patient did not take the antibiotic for every 7 patients given the information sheet (number needed to treat = 7). Amoxicillin was the prescribed antibiotic in 96% of both study groups. The number of patients scheduling a follow-up visit within 1 month was similar in both groups (11 patients who received the sheet versus 14 who did not).

RECOMMENDATIONS FOR CLINICAL PRACTICE

In this study, a written patient information sheet along with verbal counseling from the physician stopped 1 additional patient of 7 from filling an antibiotic prescription of questionable necessity. There was no change in other patient outcomes. This intervention can decrease the cost of therapy and, theoretically, may contribute to slowing the spread of antibiotic resistance in the community.

Michael DeBisschop, PharmD
Beth Robitaille, MD
University of Wyoming Family Practice
Residency Program
Casper
E-mail: medrx@uwyo.edu