Children exposed to opioids via maternal use during pregnancy were at increased risk of perinatal and postnatal physical and neurodevelopmental disabilities, according to data from more than 8,000 children.

Pregnant woman holding pills and a glass of water. Antonio_Diaz/Thinkstock

Previous studies have shown the increased risk of a range of health problems associated with maternal opioid use, including neonatal abstinence syndrome (NAS), but data on the long-term consequences of in utero opioid exposure are limited, wrote Romuladus E. Azuine, DrPH, MPH, of the U.S. Department of Health and Human Services, Rockville, Md., and colleagues.

In a study published in JAMA Network Open, the researchers reviewed data from 8,509 mother/newborn pairs in the Boston Birth Cohort, a database that included a large urban, low-income, multiethnic population of women who had singleton births at the Boston Medical Center starting in 1998.

A total of 454 infants (5%) experienced prenatal opioid exposure. Mothers were interviewed 48-72 hours after delivery about sociodemographic factors, drug use, smoking, and alcohol use.

The risk of small for gestational age and preterm birth were significantly higher in babies exposed to opioids (OR 1.87 and OR 1.49, respectively), compared with unexposed newborns.

Children’s developmental outcomes were collected starting in 2003 based on electronic medical records. A total of 3,153 mother-newborn pairs were enrolled in a postnatal follow-up study. For preschoolers, prenatal opioid exposure was associated with increased risk of lack of expected physiological development and conduct disorder/emotional disturbance (OR 1.80 and OR 2.13, respectively), compared with unexposed children. School-aged children with prenatal opioid exposure had an increased risk of ADHD (OR 2.55).

The incidence of NAS in the study population was at least 24 per 1,000 hospital births starting in 2004, and peaked at 61 per 1,000 hospital births in 2008, but remained higher than 32 per 1,000 through 2016.

The study findings were limited by several factors including potential misclassification of opioid exposure, confounding from other pregnancy exposures, loss of many participants to follow-up, and a lack of generalizability, but the results support the need for additional research, and show that the prevalence of NAS was approximately 10 times the national average in a subset of low-income, urban, minority women, the researchers said.

“However, the effect of opioids is still difficult to disentangle from effects of other childhood exposures. Policy and programmatic efforts to prevent NAS and mitigate its health consequences require more comprehensive longitudinal and intergenerational research,” they concluded.

The study findings contribute to and support the evidence of poor neurodevelopmental and emotional/behavioral outcomes for children with prenatal exposure to opioids or a history of NAS, Susan Brogly, PhD, MSc, noted in an accompanying editorial. Other studies have shown increased risks for visual impairments including strabismus, reduced visual acuity, and delayed visual maturation.

Dr. Brogly, of Queen’s University, Kingston Health Science Center, Ontario, nonetheless noted that a child’s home environment may modify the impact of prenatal opioid exposure or NAS, as evidence has shown that children with in utero heroin exposure have improved outcomes in healthy home environments.

Although the mechanism for how opioid exposure affects development remains uncertain, she suggested that future research should address “interventions to improve health outcomes in this rapidly growing population of children, regardless of the causal mechanism of impairment.”

Dr. Brogly noted that most of the opioid-using mothers in the study by Azuine et al. were unmarried, non-Hispanic white, and multiparous, and had histories of other substance abuse. She emphasized the need for supportive communities for women at risk of opioid use, who also are more likely to have unstable housing situations and histories of sexual and physical abuse.

“The risks of poor pregnancy and child outcomes in cases of maternal opioid exposure are not because of prenatal opioid exposure alone; ongoing difficult social and environmental circumstances have an important role,” and future interventions should address these circumstances to improve long-term health of high-risk women and their children, she emphasized.

The Boston Birth Cohort study is supported in part by grants from the National Institutes of Health and the U.S. Department of Health and Human Services. None of the authors had financial conflicts to disclose.

Dr. Brogly disclosed grants from the Eunice Kennedy Shriver National Institute of Child Health and Human Development outside the submitted work.

SOURCE: Azuine RE et al. JAMA Network Open. 2019 Jun 28. doi: 10.1001/jamanetworkopen.2019.6405; Brogly S. JAMA Network Open. 2019 Jun 28. doi:10.1001/jamanetworkopen.2019.6428.