Poster #53 - Early Life Stress Moderates the Impact of Later Cumulative Stress on Substance Use

• In Event: 1-115 - Poster Session 03
  In Poster Session: PS 03 Section - Developmental Psychopathology

Integrative Statement

The impact of early life stress (ELS) has been studied extensively among children adopted internationally from institutional care, due to the developmental precision that this paradigm presents: a limited duration of caregiver deprivation, followed by an enriched environment (Tottenham, 2012). Despite ample evidence associating ELS with later substance abuse (Enoch, 2011), no studies to date have investigated substance use among previously-institutionalized (PI) youth. It is possible that PI youth engage in either increased substance use, (e.g., due to impaired cognitive control; Mueller et al., 2011), or decreased substance use (e.g., due to reduced risk-taking/sensation-seeking; Loman et al., 2014).

Accounting, also, for the impact of later cumulative stress (CS) on substance use is imperative. Two theories predict opposing patterns: the “stress-sensitization” hypothesis proposes that ELS-exposed youth will demonstrate greater sensitivity to CS, whereas the “steeling” hypothesis suggests that ELS inoculates youth to effects of CS (Rutter, 2012). The present study tested whether ELS moderated the impact of CS on substance use.

The sample consisted of 65 youth (Mage = 16.3; 33 PI) in an ongoing follow-up to a longitudinal study examining PI and comparison youth (Tottenham et al., 2010). At Time 1, data were collected from participants (ages 3-17; Mage = 9.5) and parents. Families returned three times. During Times 1-3, parents completed the Life Events Questionnaire (LEQ), which measures the impact of recent negative life events (Sarason et al., 1978). A total sum score for Times 1-3 was calculated to measure CS. At Time 4, youth reported on use of various substances. Responses were coded to reflect “no use” (0), “infrequent use” (1), or “frequent use” (2), and a total substance use score was summed. Lastly, duration of ELS was calculated (controls = 0; PI subjects = age of adoption).

Results indicate that, controlling for age, neither PI status (B = -.82, p = .11) nor CS (B = -.42, p = .48) predicted substance use, but the interaction was significant (B = 1.5, p = .02; see Figure 1). Only substance use in PI youth increased with CS. Similarly, neither duration of ELS (B = -.18, p = .44) nor CS (B = .04, p = .90) predicted substance use. However, there was a significant interaction (B = .98, p < .001; see Figure 2). Youth with shorter durations of ELS decreased in substance use as CS increased, whereas youth with longer durations of ELS increased in use as CS rose.

The present study is the first to examine substance use in PI and comparison youth. Findings favored the “stress-sensitization” hypothesis, whereby greater ELS sensitized youth to the effects of CS on substance use. However, low rates of substance use among PI youth with low CS underscore post-adoption resilience, suggesting that potential effects of early deprivation, such as reductions in risk-taking or sensation-seeking, may protect against substance involvement. The finding that comparison youth decrease in substance use as CS increases is anomalous. Further research should test potential 3-way interactions with genetic and other environmental factors to elucidate these results.

Authors

• Austin Joy Blake, Arizona State University
  Presenting Author

• Emilia Ninova, University of California, Los Angeles
  Non-Presenting Author

• Yael Waizman, University of California, Los Angeles
  Non-Presenting Author

• Joao Guassi Moreira, University of California, Los Angeles
  Non-Presenting Author

• Nim Tottenham, Columbia University
  Non-Presenting Author

• Jennifer Silvers, UCLA
  Non-Presenting Author