(C-063) Single-Dose Doxycycline for Lyme Disease Prophylaxis in Children in a Large United States Healthcare Database, 2016-2020

Background: Lyme disease can be effectively prevented by a single dose of doxycycline (SDD) as post-exposure prophylaxis (PEP) following a high-risk tick bite. Children aged 5–9 years are typically one of the highest risk groups. Historically, clinicians avoided prescribing doxycycline for children aged < 8 years but recent guidelines have confirmed the safety of short ( < 21 days) courses in children of all ages.

Objectives: To understand the epidemiology of Lyme disease PEP in children by describing the frequency and patterns of single dose of doxycycline dispensing among a cohort of pediatric patients.

Methods: We performed a retrospective cohort study using claims data from five U.S. data partners in the Sentinel Distributed Database. Patients aged 0–19 years with Medicaid or commercial insurance coverage were included. Children who received ≥1 SDD (≤200 mg) dispensing during Jan 2016 – Dec 2020 were identified. We estimated the rate of SDD per 10,000 eligible member-years and described associated patient sociodemographic and geographic characteristics and SDD dispensing seasonal patterns. We employed Poisson regression to compare rates and estimate unadjusted rate ratios (RR), and 95% confidence intervals (CI).

Results: Among the cohort of 72,347,267 eligible pediatric patients, 19,976 received ≥1 SDD dispensing of these, most (97.1%) received only one dispensing. The rate of SDD dispensing was 1.1 per 10,000 eligible member-years overall but varied by geography; rates were 3.68, 0.51, and 0.22 among patients living in high (10 Lyme disease cases per 100,000 population), neighboring, and low incidence states, respectively. Most (80.4%) SDD dispensings were during the six summer and fall months when blacklegged ticks are most active. The mean age of patients who received ≥1 SDD dispensing was 12.9 years; most (86.0%) were for patients aged 8–19 years. SDD rates were higher in male than female patients (1.18 and 1.07, respectively) and in older than younger patients (1.65 and 0.38 in ages 8–19 and 0–7, respectively). SDD rates were higher among children living in rural zip codes compared to those living in suburban or urban zip codes (3.47, 1.40, and 0.90, respectively). Rates were higher among those with commercial insurance than with Medicaid coverage (2.05 and 0.89, respectively, unadjusted RR 2.31 (95% CI: 2.24, 2.37)).

Conclusions: SDD was dispensed most often among children living in rural areas in states with high Lyme disease incidence, suggesting that most dispensings were for Lyme disease PEP. Lower rates of SDD dispensing among younger children and children with Medicaid coverage highlight important gaps in Lyme disease prevention and suggest a need for targeted interventions and clinician education.