Objective: To examine the relationship between maternal opioid agonists, methadone, or buprenorphine (BPH), and concurrent psychiatric medication use on length of hospitalization (LOS) among infants with neonatal abstinence syndrome (NAS).
Methods: We reviewed the charts of infants born at Boston Medical Center between 2003 and 2009 with a diagnosis of NAS whose mothers were prescribed methadone or BPH for opiate addiction. Univariate and multivariate linear regression analyses were used to examine associations between maternal opioid substitution concurrent with psychiatric medication use and infant LOS. We also tested whether exposure to BPH was associated with a shorter hospitalization.
Results: A total of 273 mother-infant pairs were identified. The average LOS for all infants was 22.9 days (SD: 10.9). In bivariate analyses, maternal use of any psychiatric medication was associated with a longer infant LOS (P < 0.005). Compared with those prescribed methadone alone (n = 158), those also taking benzodiazepines (n = 56) had a 5.88-day longer LOS (95% confidence interval [CI]: 2.15-9.60, P = 0.002). Infants of mothers taking methadone plus an selective serotonin re-uptake inhibitor (n = 51) had a longer LOS (β = 4.47, 95% CI: 1.15-7.79) compared to methadone alone; results remained significant in an initial multivariate model, however the effect was attenuated when additional psychiatric medication use was added to the model. Compared with those exposed to methadone, those exposed to BPH (n = 22) had a significantly shorter LOS (ß = -7.35, CI: -0.18 to -14.52, P = 0.04).
Conclusions: Maternal use of prescribed methadone and benzodiazepines, compared to methadone alone, increased LOS for infants with NAS by 6 days. Maternal use of BPH was associated with a shorter LOS.