Background: The epidemiology of acute bacterial skin and skin structure infection (ABSSSI) is not well characterized in children, although children have an elevated risk of methicillin-resistant Staphylococcus aureus (MRSA) infection, which is a leading cause of ABSSSI associated with high morbidity and mortality.
Objectives: To determine the incidence of ABSSSI in the pediatric population, and to estimate the frequency of antibiotic prescriptions in pediatric ABSSSI patients.
Methods: The Merative MarketScan Commercial and Medicaid claims databases in the US from 2012 to 2022 was analyzed. Enrollees aged 2 to < 18 years with continuous enrollment (in the analysis year and year prior) and those aged < 2 with active enrollment were included in each annual cohort. ABSSSI episodes were counted as distinct incident cases with at least 42 day-gap between two sequential diagnoses, which were used to calculate annual incidence. The percentage of incident cases who were dispensed antibiotics within 14 days after the first day of an episode were summarized for any antibiotics and antibiotics with activities against MRSA based on literature and clinical review. Poisson regression was used to investigate ABSSSI incidence by subgroup. Chi-square tests were used to compare antibiotic prescriptions by subgroup in ABSSSI patients.
Results: In commercially insured population, from 2012 to 2019, the annual incidence of ABSSSI (episodes per 1000 person-years) was lower in infants aged < 1 year (15 to 17) compared to other age groups (20 to 29) (p < .0001 for comparing every older age group to infants aged < 1 year); and from 2020 to 2022, while incidence in most age groups decreased, incidence in 12 to < 18 years (21 to 23) remained higher than infants aged < 1 year (15 to 16) (p < .0001). The Medicaid population showed higher ABSSSI incidence than the commercial population in the early 2010s (e.g. for birth to < 1 year, the incidence (episodes per 1000 person-years) for Medicaid and commercial populations were 27 (95% CI: 26-28) and 16 (95% CI: 16-17), respectively in 2012), then the differences gradually diminished over time for all ages. In the commercial population, infants aged < 1 year (41% for all antibiotics and 17% for antibiotics for MRSA) were dispensed less antibiotics than other pediatric age groups (63-69% for all antibiotics and 31-32% for antibiotics for MRSA) (p < .0001). The Medicaid population had consistently higher rates of antibiotic prescriptions than the commercial population, with more pronounced differences in the early 2010s.
Conclusions: Variations in annual ABSSSI incidence and antibiotic prescriptions were observed by pediatric age group, and by insurance in 2012-2022. This work fills in the gap of the literature on long-term trends of ABSSSI epidemiology by pediatric age group.
