Social Vulnerability and Initiation of Pharmacotherapy for Gestational Diabetes Mellitus in a Medicaid Population

Objective: Our study examines the association between social vulnerability index (SVI) and pharmacotherapy initiation for gestational diabetes mellitus (GDM).Methods: We studied a retrospective cohort of pregnant patients with GDM, enrolled in Tennessee Medicaid, who gave birth between 2007 and 2019. Enrollment files were linked to birth and death certificates, state hospitalization regis-tries, and pharmacy claims. SVI, measured at the community level and determined by residential census tract, ranged from 0 to 100 (low to high vulnerability). Multivariable logistic regression assessed the association between SVI and the odds of initiating the most common pharmacotherapies for GDM-insulin, glyburide, or metformin-and adjusted for relevant covariates. SVI was modeled with restricted cubic splines to account for nonlinear associations, using the median Tennessee SVI as a reference. Secondary analysis assessed associations with the SVI subthemes. Results: Among 33,291 patients with GDM, 21.7% (7,209) initiated pharmacotherapy during pregnancy. Patients from areas with higher SVI were more likely to be non-Hispanic Black with higher body mass index, whereas those with lower SVI were more likely to be nulliparous. Multivariable modeling demonstrated a complex nonlinear association between SVI and GDM pharmacotherapy initiation, relative to the reference. Higher SVI was associated with elevated odds of GDM pharmacotherapy initiation (e.g., odds ratio 1.11 [95% confidence interval 1.02-1.22] for SVI 80) and low to medium SVI had variable nonsignificant associations with GDM pharmacotherapy initiation, relative to the reference (lower odds of initiation for values 25-50, higher odds of initiation for values < 25). Secondary analysis demonstrated a nonlinear association between subtheme 3 and the odds of GDM pharmacotherapy initiation. Conclusion: Social vulnerability is associated with initiation of pharmacotherapy for GDM, highlighting the possible role of social determinants of health in achieving glycemic control.& COPY; 2022 Jacobs Institute of Women's Health, George Washington University. Published by Elsevier Inc. All rights reserved.