A prospective study of antibiotic use and associated infections in young children

This study examines antibiotic usage and associated infections in infants a nd young children in Iowa. Longitudinal data were collected using a cohort recruited at birth from eight hospitals in eastern Iowa. Parents of recruit ed children were mailed questionnaires at 6 weeks, and 3, 6, 9, 12, 16, and 20 months of age. The cumulative incidence of antibiotic use and associate d infections was determined using Kaplan-Meier survival analysis. There wer e data on 1368 children. Antibiotic use was common in our cohort and increa sed with age. Beginning at age 3 months, approximately 50% of the cohort wa s exposed to an antibiotic during each reporting period. Otitis media was t he most common indication and was responsible for 67.3% of antibiotic use. Children were most frequently treated with amoxicillin, followed by the cep halosporins and sulphonamides. By 12 and 20 months of age 79.0% and 92.5% o f the children, respectively, had been treated with at least one course of antibiotics. Children received antibiotics for a median of 43 days by 20 mo nths of age. Males were more likely to experience any antibiotic exposure t han females (hazard ratio = 1.18) and showed a trend for more days of use ( P = 0.052). There was a small but significant variation in antibiotic usage in the different recruitment communities (P = 0.02).