Antibiotic use in Ontario facilities that provide chronic care

Objective: To determine the incidence and variability of antibiotic use in facilities which provide chronic care and to determine how often clinical c riteria for infection are met when antibiotics are prescribed in these faci lities. Design: A prospective, la-month, observational cohort study. Setting: Twenty-two facilities which provide chronic care in southwestern O ntario. Participants: Patients who were treated with systemic antibiotics over the study period. Measurements: Characteristics of antibiotic prescriptions (name, dose, dura tion, and indication) and clinical features of randomly selected patients w ho were treated with antibiotics. Results: A total of 9,373 courses of antibiotics were prescribed for 2,408 patients (66% of the patients in study facilities). The incidence of antibi otic prescriptions in the facilities ranged from 2.9 to 13.9 antibiotic cou rses per 1,000 patient-days. Thirty-six percent of antibiotics were prescri bed for respiratory tract infections, 33% for urinary infections, and 13% f or skin and soft tissue infections. Standardized surveillance definitions o f infection were met in 49% of the 1,602 randomly selected patients who wer e prescribed antibiotics. Diagnostic criteria for respiratory, urinary, and skin infection were met in 58%, 28%, and 65% of prescriptions, respectivel y. One third of antibiotic prescriptions for a urinary indication were for asymptomatic bacteriuria. Adverse reactions were noted in 6% of prescriptio ns for respiratory and urinary infections and 4% of prescriptions for skin infection. Conclusions: Antibiotic use is frequent and highly variable amongst patient s who receive chronic care. Reducing antibiotic prescriptions for asymptoma tic bacteriuria represents an important way to optimize antibiotic use in t his population.