Neonatal Outcomes in a Medicaid Population With Opioid Dependence

Abstract Confounding may account for the apparently improved infant outcomes after prenatal exposure to buprenorphine versus methadone. We used Massachusetts Medicaid Analytic eXtract (MAX) data to identify a cohort of opioid-dependent mother-infant pairs (2006–2011), supplemented with confounder data from an external Boston, Massachusetts, cohort (2015–2016). Associations between prenatal buprenorphine exposure versus methadone exposure and infant outcomes in the MAX cohort were adjusted for measured MAX confounders and were additionally adjusted for unmeasured confounders with bias analysis using external cohort data. A total of 477 women in MAX were treated with methadone and 543 with buprenorphine. More buprenorphine users than methadone users were white and used psychotropic medications. After adjustment for MAX confounders, risk ratios among infants exposed to buprenorphine versus those exposed to methadone were 0.45 (95% confidence interval (CI): 0.34, 0.61) for preterm birth (birth at