A Prospective Cohort Study of Influences on Externalizing Behaviors Across Childhood: Results From a Nurse Home Visiting Randomized Controlled Trial

Abstract

Objective: This study investigated genetic and environmental influences on behavior in a cohort of 600 children followed prenatally to 18 years.

Method: A randomized controlled trial of prenatal/infancy nurse home visits (NHV) was conducted in 600 predominantly African American mothers and their firstborn children from Memphis, TN. Mothers were assessed in pregnancy for mental health (MH), self-efficacy, and mastery. Mothers reported longitudinally on smoking and alcohol/drug use. The functional polymorphisms SLC6A4 5-HTTLPR, FKBP5 rs1360780 and DRD2/ANKK1 rs1800497 were genotyped together with 186 ancestry informative markers. Composite externalizing disorders (ED) continuous total scores from the mother-report Achenbach Child Behavior Checklist were included as dependent variables in regression analyses for time points 2, 6, 12, and 18 years.

Results: Behaviors at younger ages strongly predicted later behaviors (p < .0001). Children whose mothers had high self-efficacy and had received NHV were better behaved at age 2 years. Poorer maternal MH adversely influenced ED up to 12 years, but at age 18 years, maternal mastery exerted a strong, positive effect (p = .0001). Maternal smoking was associated with worse ED at 6 and 18 years. Main and interactive effects of genetic polymorphisms varied across childhood: FKBP5 rs1360780 up to age 6, 5-HTTLPR from 6 to 12, and DRD2/ANKK1 rs1800497 from 2 to 18 years.

Conclusion: Our study suggests that maternal MH and resilience measured in pregnancy have long-lasting effects on child behavior. Maternal smoking across childhood and genetic factors also play a role. NHV had a positive effect on early behavior. Our findings have implications for prevention of pathological behaviors in adulthood. Clinical trial registration information-Age-17 Follow-Up of Home Visiting Intervention; https://ichgcp.net/clinical-trials-registry/NCT00708695" title="See in ClinicalTrials.gov">NCT00708695.

Keywords: 5-HTTLPR; Achenbach Child Behavior Checklist; DRD2/ANKK1; FKBP5; nurse home visiting.

Published by Elsevier Inc.

Figures

FIGURE 1

Independent effects on firstborn children’s composite externalizing disorders (ED) scores at three time points. Note: p value scores: 0: p > .1; 1: p = .1–.05; 2: p < .05–.01; 3: p < .01–.005; 4: p < .005–.0001; 5: p < .0001. FB = firstborn child; FB ANKK1 = child DRD2/ANKK1 rs1800497 genotype; FB FKBP5 = child FKBP5 rs1360780 genotype; M = mother; M cigs/day = maternal smoking at child age 6 yrs; M PM = maternal Pearlin mastery score; M SE = maternal self-efficacy score; NHV = nurse home visiting group vs. controls; previous ED = ED score at previous time point. Interaction terms: NHV × M SE; child FKBP5 rs1360780 genotype × M PM; child DRD2/ANKK1 rs1800497 × M PM. Full details of the regression analyses are provided in Table 1.