Infant Sleep and Behavioral Problems During the Second Year: The Moderating Role of Socioeconomic Risk

• In Event: Developmental Psychopathology Perspectives on Externalizing Behavior Problems Among Young Children

Abstract

Short and disrupted sleep has been identified as a risk factor for child behavioral problems, in that sleep is a biological regulatory system that could influence individuals’ cognitive and emotional regulation (Dahl, 1996). However, previous research investigating the effect of sleep on child adjustment mainly focused on school-age children (e.g., El-Sheikh et al., 2010), with less attention paid to sleep’s effects in infancy and toddlerhood. Importantly, predictive linkages between sleep and adjustment in young children has been inconsistent (e.g., Anders et al., 2012). We propose that these inconsistencies may be the result of ignoring the role of environmental factors in moderating sleep’s effects. Indeed, diathesis-stress models of development emphasize interactive effects of environmental stressors and individual vulnerabilities on adjustment (Monroe & Simons, 1991). Because family socioeconomic risk represents a distal environmental stressor that has deleterious effects on infant outcomes (Bradley & Corwyn, 2002), the present study tested how family socioeconomic risk and infant sleep jointly predict infant externalizing and internalizing behavior during the second year. It was hypothesized that short and disrupted sleep will have a greater deleterious effect on infant behavioral problems under high socioeconomic risk conditions.

Data of 120 families (48.3% male) were drawn from an NICHD-funded study focusing on parenting, sleep and infant development. At one month, parents reported their family income, maternal and paternal age, and education. The reversed standardized scores of these variables were composited into a family socioeconomic risk score, with higher scores indicating higher levels of risk. At 12, 18 and 24 months, mothers reported their infants’ externalizing and internalizing problems via the Infant-Toddler Social and Emotional Assessment (ITSEA; Carter & Briggs-Gowan, 2006). At each occasion, infant sleep quantity (i.e., sleep duration) and quality (i.e., sleep fragmentation) were assessed via AW-64 actiwatches (Philips/Respironics, Inc.) and averaged across seven consecutive days.

Multilevel modeling was conducted to examine how family socioeconomic risk and infant sleep predicted infant behavioral problems after controlling for infant age and sex. The effects of sleep quantity and quality were tested separately. For the model with sleep duration as the predictor (Table 1), shorter sleep duration and greater family socioeconomic risk predicted more externalizing behaviors in infants. Moreover, they interactively predicted infant externalizing behavior, such that the detrimental impact of inadequate sleep on infant externalizing was stronger when family socioeconomic risk was high (Figure 1). Sleep fragmentation was not related to infant externalizing behaviors, and no significant interactions or main effects were found in predicting infant internalizing behaviors.

Consistent with a diathesis-stress model (Monroe & Simons, 1991), the results for infant externalizing behavior suggested that inadequate sleep, as an individual diathesis, may have a more adverse effect on infant externalizing behaviors in high than in low socioeconomic risk families. The findings highlight the importance of considering environmental stressors when understanding the impact of sleep on children’s outcomes, and that sleep interventions on externalizing behaviors might especially target infants in high socioeconomic risk environments.

Authors

• Liu Bai, Pennsylvania State University, University Park
  Presenting Author

• Hui Wang, Beijing Normal University
  Non-Presenting Author

• Brian Crosby, Pennsylvania State University
  Non-Presenting Author

• Douglas M Teti, The Pennsylvania State University
  Non-Presenting Author