Trajectories of Externalizing Behavior Problems from Age 3 to 13 in Children with Prenatal Substance Exposure: The Maternal Lifestyle Study

Objective: Although prenatal substance exposure (PSE), such as tobacco, marijuana, and cocaine, is linked with greater externalizing behavior, little is known about how PSE may contribute to different childhood developmental trajectories of externalizing behavioral problems. The purpose of the present study is to: 1) identify developmental trajectories of externalizing problems in children with PSE; and 2) examine whether trajectories differ by PSE and other environmental and biological correlates.

Methods: 1,257 mother-infant/child dyads (597 girls, 660 boys), primarily African-American and of low socioeconomic status, were prospectively enrolled in a longitudinal, multisite study of prenatal cocaine or opiate exposure at birth from 1993 to 1995. Infant meconium or maternal self-report indicated 79% of women used at least 1 substance during pregnancy (43% used cocaine, 8% opioid, 60% alcohol, 53% tobacco, 24% marijuana), with 58% having used 2 substances and 38% having used 3 or more substances during pregnancy. Externalizing behavior problems were assessed with the Child Behavior Checklist at ages 3, 5, 7, 9, 11, and 13 (91% retention). Child gender, maternal psychological distress, assessed at 4 months of child age via the Brief Symptom Inventory, and quality the caregiving environment, assessed at 10 months via The Home Observation for Measurement of the Environment (HOME)- Preschool, were used as covariates.

Results: Latent class growth model indicated that a model with four classes is the best fitting model (BIC= -20822, entropy= .84). The four externalizing behavior trajectory groups were: 1) no-risk group (21%) constantly reporting below the mean (< 50) T-score; 2) average group (38%) with T-scores around the mean; 3) moderate group (32%) with T-scores hovering in borderline range (60); and 4) elevated-chronic group (8%) with T-scores > 65 above the clinical cut-point.

Multinomial regression analyses indicated that, compared to the no-risk group, prenatal nicotine exposure was associated with increased odds of being in the average group (OR= 1.77, 95% CI= 1.10 - 2.84), in the moderate group (OR= 2.89, 95% CI = 1.76 - 4.77), and in the elevated-chronic group (OR= 3.49, 95% CI= 1.62 - 7.52). Prenatal opioid exposure was also associated with increased odds of being in the average group (OR= 2.88, 95% CI= 1.07 - 7.71) and in the elevated-chronic group (OR= 4.07, 95% CI= 1.20 - 13.9), compared to the no-risk group. Higher biological mothers’ psychological distress was associated with increased odds of being in the average (OR= 1.48, 95% CI= 1.17-1.87), moderate (OR= 2.39, 95% CI= 1.86 - 3.08), and elevated-chronic (OR= 3.78, 95% CI= 2.49 - 5.74) groups. No gender or HOME scores were related to different trajectories.

Conclusions: Our study indicated that behavioral problems can be identified as early as age 3 years in children with PSE living in high risk-environments. Forty-percent of the children were identified following problematic trajectories, which were associated with prenatal exposure to nicotine and opioids and with maternal psychological distress. Our findings underscore the need for comprehensive early intervention and prevention programs focused on 2-3 year-olds with early symptoms of externalizing problems.