Antidepressant Adherence Using Group-Based Trajectory Modeling Among Postpartum Women With Texas Medicaid

OBJECTIVES: Little is known regarding antidepressant adherence trajectories among postpartum women in the US. The objective of this study is to describe antidepressant use among postpartum women with Texas Medicaid and determine factors associated with adherence trajectories.

METHODS: This retrospective analysis of Texas Medicaid claims (1/1/18-6/30/22) included women 12-55 years with at least one delivery, continuously enrolled 84 days pre- and 12 months post-delivery, and who received an antidepressant within 90 days post-delivery. The dependent variable was antidepressant adherence, defined as proportion of days covered and measured in 30-day increments for 270 days post-antidepressant initiation. The independent variables were age, race/ethnicity, urbanicity, prenatal care, postpartum care, baseline depression/anxiety, baseline substance use disorder (SUD), cesarean delivery, preterm birth, and pregnancy complications. Group-based trajectory modeling (GBTM) was used to identify antidepressant adherence trajectory groups. Multinomial logistic regression was used to determine factors associated with adherence trajectory group membership.

RESULTS: Included patients (N=15,667) were 27.4±5.9 years old and 41.7% were White. Most resided in urban counties (78.0%), and had 6.4±3.5 prenatal, 3.1±2.8 postpartum care visits, and 1.4±0.9 pregnancy complications. Nearly half (49.8%) had baseline depression/anxiety, 17.2% had baseline SUD, 37.4% had cesarean delivery, and 13.9% had preterm birth. GBTM revealed 5 membership groups: consistent high (19.0%), fluctuating (22.5%), slowly decreasing (13.3%), and rapidly decreasing (21.8%) adherence, and early and consistent nonadherence (23.4%). Increasing age, non-Black race, urban residence, increasing postpartum care visits, and baseline depression/anxiety were associated with the consistent high adherence trajectory compared to most lower adherence trajectories. However, baseline SUD and preterm birth were associated with most lower adherence trajectories compared to the consistent high adherence trajectory.

CONCLUSIONS: GBTM revealed unique patterns of postpartum antidepressant adherence behaviors. Adherence promoting interventions should be tailored to patients who are younger, Black, live in rural counties, have SUD, or preterm birth.