Buprenorphine Dosing Frequency is not Associated with Maternal Stability and Neonatal Outcomes

Abstract

Pregnancy alters pharmacokinetics for buprenorphine with variation in dosing suggested from the common once a day (QD) scheme outside pregnancy. Our objective was to determine the relationship between dosing frequency and maternal stability, as measured by rates of relapse and prenatal compliance, and neonatal abstinence syndrome (NAS) rates. This study was from a longitudinal cohort of women receiving care through the PATHways program between 2015 and 2021. We compared outcomes for enrollees prescribed twice a day (BID) or greater dosing of buprenorphine at delivery versus QD. Maternal compliance with treatment goals included inappropriate maternal UDS results, reported illicit use at prenatal appointments, and no-call, no-show visits. This score was the percentage meeting goals from all prescribed visits. Women not taking buprenorphine at delivery were excluded as well as those with less than 6 weeks duration of antepartum therapy. Fisher’s exact test was used for our statistical analysis. 284 patients were included, with 226 (79.5%) underwent QD dosing versus 58 dosed BID or TID. Demographics were similar between groups. Mean total dose per day was significantly higher in the BID/TID group (14.61 ± 5.3 vs 11.86 ± 5.01, P=0.003), see Table 1. When comparing dosing frequency subgroups, maternal compliance scores were not significantly different (0.54± 0.31 vs 0.55± 0.31, P=0.83). No difference was evident in the total antepartum visits attended per group. When neonatal outcomes were assessed, no differences between birthweight, gestational age at delivery, rates of NAS, NAS treatment duration, or neonatal length of stay, see Table 2. Dosing frequency of buprenorphine was related to total daily dose but was not associated with maternal stability or neonatal outcomes. The presence of equipoise for this clinical finding provides justification for a randomized trial to evaluate differences based on dosing frequency.View Large Image Figure ViewerDownload Hi-res image Download (PPT)