Institutionally deprived young children often display distinctive patterns of attachment, classified as insecure/other (INS/OTH), with their adoptive parents. The associations between INS/OTH and developmental trajectories of mental health and neurodevelopmental symptoms were examined. Age 4 attachment status was determined for 97 Romanian adoptees exposed to up to 24 months of deprivation in Romanian orphanages and 49 nondeprived UK adoptees. Autism, inattention/overactivity and disinhibited-social-engagement symptoms, emotional problems, and IQ were measured at 4, 6, 11, and 15 years and in young adulthood. Romanian adoptees with over 6 months deprivation (Rom>6) were more often classified as INS/OTH than UK and Romanian adoptees with less than 6 months deprivation combined. INS/OTH was associated with cognitive impairment at age 4 years. The interaction between deprivation, attachment status, and age for autism spectrum disorder assessment was significant, with greater symptom persistence in Rom>6 INS/OTH(+) than other groups. This effect was reduced when IQ at age 4 was controlled for. Age 4 INS/OTH in Rom>6 was associated with worse autism spectrum disorder outcomes up to two decades later. Its association with cognitive impairment at age 4 is consistent with INS/OTH being an early marker of this negative developmental trajectory, rather than its cause.

A considerable body of evidence suggests that early caregiving may affect the short-term functioning and longer term development of the hypothalamic–pituitary–adrenocortical axis. Despite this, most research to date has been cross-sectional in nature or restricted to relatively short-term longitudinal follow-ups. More important, there is a paucity of research on the role of caregiving in low- and middle-income countries, where the protective effects of high-quality care in buffering the child's developing stress regulation systems may be crucial. In this paper, we report findings from a longitudinal study (N = 232) conducted in an impoverished periurban settlement in Cape Town, South Africa. We measured caregiving sensitivity and security of attachment in infancy and followed children up at age 13 years, when we conducted assessments of hypothalamus–pituitary–adrenocortical axis reactivity, as indexed by salivary cortisol during the Trier Social Stress Test. The findings indicated that insecure attachment was predictive of reduced cortisol responses to social stress, particularly in boys, and that attachment status moderated the impact of contextual adversity on stress responses: secure children in highly adverse circumstances did not show the blunted cortisol response shown by their insecure counterparts. Some evidence was found that sensitivity of care in infancy was also associated with cortisol reactivity, but in this case, insensitivity was associated with heightened cortisol reactivity, and only for girls. The discussion focuses on the potentially important role of caregiving in the long-term calibration of the stress system and the need to better understand the social and biological mechanisms shaping the stress response across development in low- and middle-income countries.