Antibiotic use in children who have asthma: results of retrospective database analysis

Inappropriate antibiotic use is a well-recognized public health problem because of its association with the emergence of resistant bacteria. It also is a source of unnecessary health care costs and of potentially severe adverse drug reactions. Although there are no evidence-based indications for the use of antibiotics in the treatment of asthma in the absence of comorbid bacterial conditions, physicians might feel more pressure to prescribe them to children with this common chronic disease. The objectives of this study were to (a) determine if antimicrobial prescription utilization rates are higher for pediatric patients with asthma than a matched comparison group and (b) identify common variables (gender and age) that might explain higher antibiotic utilization rates in children.

Using administrative claims data, we conducted a retrospective cohort study of children with asthma (age range 5 to 18 years) who were members of a large health plan from January 1, 2000, to December 31, 2002, in the southeastern United States. A comparison group was created that was matched according to age, sex, regional codes, and insurance product line. International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes were used to identify asthmatic patients (493.xx), as well as to link antibiotic prescriptions to diagnosis codes from claims for medical office visits.

Asthmatics consistently received significantly more services, including a mean of 1.74 (SD 1.82) antibiotics per patient per year (PPPY) compared with a mean of 0.96 (SD 1.32) antibiotics PPPY for nonasthmatics (t=25.71, P <0.001). Asthmatics received antibiotics more often for all diagnoses. The more frequent receipt of antibiotics was true for conditions related to the respiratory tract (e.g., upper respiratory infection and bronchitis) as well as for conditions unrelated to the respiratory tract (e.g., urinary tract infection and acne). A diagnosis of asthma significantly increased the likelihood of a prescribed antibiotic by 26% to 86%.

This study demonstrated that pediatric asthmatic patients received significantly more antibiotic prescriptions than nonasthmatics for conditions caused by bacteria as well as for conditions more likely to be viral in origin. In this era of concern about the widespread use of antibiotics and consequent antimicrobial resistance, further research needs to be conducted concerning the appropriateness of antibiotics in the treatment of asthma. Studies on the appropriate use of antibiotics in asthma could help reduce the overall use of antibiotics in children.