Prescription patterns relevant to young people with epilepsy of childbearing potential

Rationale.

Young people with epilepsy of childbearing potential (YPWECP) are vulnerable to a variety of adverse health outcomes due to teratogenic antiseizure medications (ASMs) and drug-drug interactions between ASMs and contraceptives that can lead to breakthrough seizures and/or contraceptive failure. To better understand reproductive healthcare provision for YPWECP, we conducted a retrospective analysis of relevant prescription patterns.

Methods

We analyzed procedural and medication data for YPWECP ages 13–21 years (n = 1525) from 2011 through 2021 at a single tertiary-care pediatric medical center to investigate rates of (1) prescription of folic acid, (2) prescription of an enzyme-inducing ASM<6 months before or after hormonal contraception initiation (or < 3 years after subdermal implant placement), (3) prescription of lamotrigine < 6 months before or after an estrogen-containing contraceptive that could affect lamotrigine serum concentrations, and (4) documentation of any contraceptive medication or device that overlaps initiation of a patient’s first teratogenic ASM. We performed statistical analyses with sample proportion z-tests. We then used logistic regression and generalized estimating equations to evaluate for associations between patient characteristics and prescription patterns.

Results

Among 1525 YPWECP, less than half (41 %, n = 629) were prescribed folic acid during the study period (95 % CI 38.8–43.7). Of YPWECP prescribed an enzyme-inducing ASM, 24 % (186/766) were co-prescribed a hormonal contraceptive that adversely interacts with the ASM (95 % CI 21.2–27.3 %). Of those prescribed lamotrigine during the study period, 24 % (111/472) had documentation of an estrogen-containing medication that could affect lamotrigine serum concentrations < 6 months before or after that prescription (95 % CI 19.7–27.3 %). Of those prescribed a teratogenic ASM, only 13 % (82/638) had documentation of contraception prior to (or within the same month as) starting their first teratogenic ASM (95 % CI 10.3–15.5 %). Older age was associated with increased odds of contraceptive coverage prior to initiation of the first teratogenic ASM and was also associated with increased odds of having contraceptives co-prescribed with ASMs that could interact. No significant associations were found between race/ethnicity and any outcomes.

Conclusions

YPWECP experience low rates of folic acid prescription and low rates of contraceptive coverage while prescribed teratogenic ASMs. Many YPWECP, particularly older adolescents, are at increased risk for contraceptive failure and/or breakthrough seizures due to drug-drug interactions. Results demonstrate a need for increased focus on reproductive healthcare for YPWECP. Future studies should evaluate interventions aimed at improving these outcomes.