This study examined the role that easy infant temperament and cumulative environmental risk play in predicting cognitive, language, and behavioral outcomes in 3-year-old children at high social risk.
Subjects were 412 mother-infant dyads, recruited at birth, participating in a longitudinal study examining the effects of prenatal methamphetamine on child development. This analysis includes a subsample (n = 290) of the study with a completed 3-year visit. Temperament was assessed by the Infant Behavior Questionnaire at 12 months. Factor analysis from well-validated measures generated “easy” and “difficult” temperament profiles and a profile for high-risk environment. Caretaker receptive vocabulary served as a proxy for intelligence quotient. Outcomes at 3 years included motor and mental development, behavior problems, and language. Linear regression and hierarchical linear modeling examined the effects of temperament, high-risk environment, and caregiver receptive language on outcomes adjusting for maternal drug use and demographic and socioeconomic covariates.
Internalizing and externalizing behaviors were lower in children with easy temperament and higher with increased environmental risk. Easy temperament attenuated behavioral problems only in the setting of lower environmental risk. Caregiver receptive language was associated with lower internalizing scores. High-risk environment and temperament factors were not related to cognitive or motor outcomes. Prenatal methamphetamine exposure was not associated with 3-year-old outcomes, nor did it alter the protective effects of an easier temperament on child behavior.
Children growing up in adverse social environments had increased behavioral problems and compromised language development. Conversely, an easy temperament acts as a protective factor for social-emotional development and could be related to resilience.
From the *John A. Burns School of Medicine, University of Hawaii, Honolulu, HI; †Pediatrics Division, Brown Center for the Study of Children at Risk, Warren Alpert Medical School at Brown University and Women and Infants Hospital, Providence, RI; ‡Los Angeles Biomedical Institute at Harbor-UCLA Medical Center, Torrance, CA; §David Geffen School of Medicine at UCLA, Los Angeles, CA; ∥University of Tulsa, Tulsa, OK; ¶Blank Children's Hospital, Iowa Health, Des Moines, IA; #Center on Young Adult Health and Developtment, University of Maryland School of Public Health, College Park, MD; **National Institute on Drug Abuse, Chemistry, and Drug Metabolism Section, Baltimore, MD; ††Long Beach Memorial Medical Center, Long Beach, CA.
Received August 2010; accepted November 2010.
This work was supported by NIH grants 2R01DA014948 and 1K23DA020801 from National Institutes on Drug Abuse and in part by the grants 5P20RR011091 and 3M01RR00425 from National Center for Research Resources.
Dr. Chris Derauf wrote the first draft of the manuscript, and there was no honorarium, grant, or other form of payment given to anyone to produce this manuscript.
Address for reprints: Chris Derauf, MD, Department of Pediatrics, John A. Burns School of Medicine, University of Hawaii, 1319 Punahou Street, Honolulu, HI 96826; e-mail: email@example.com.