- Top of page
Institutional deprivation is multifaceted and includes adverse psychosocial and nutrition-related components. In this study we partitioned these risks in relation to cognitive impairment and mental ill health, and explored the mediating role of reduced head/brain size. There were 138 participants (61 males, 77 females) in the study. Participants were Romanian adoptees who had experienced at least 2 weeks of early institutional deprivation. The sample was stratified on the basis of duration of deprivation (high risk >6mo in institutions) and sub-nutrition (i.e. 1.5 SD below UK age-related norms for weight at UK entry). UK children adopted before 6 months of age and a group of non-institutionally deprived Romanian children constituted the comparison groups. Duration of deprivation was associated with smaller head circumference, lowered IQ, and increased mental heath problems, independently of effects found for sub-nutrition on head circumference and IQ. The mediating role of head circumference was limited to either sub-nourished (IQ) or non-sub-nourished (inattention/overactivity and disinhibited attachment) subgroups. Many negative effects of early deprivation, including stunted brain growth, occur without sub-nutrition: psychosocial deprivation plays a major role in neurodevelopmental effects of deprivation. Further studies of functional and structural neuroanatomy following institutional deprivation are required to delineate the role of brain development in its effects.
The negative effects of early, profound institutional deprivation on development and mental health persist into later life despite radical improvements in social environments following adoption.1,2 Compelling evidence for this comes from the English and Romanian Adoptees (ERA) study which examined the outcomes for a cohort of children who spent their early infancy living in the extremely deprived conditions of the state institutions of the Ceauşescu regime in Romania at the end of the 1980s, and who were subsequently adopted into UK families before 3 years 7 months of age. Despite a remarkable degree of recovery for even some of the most deprived children,1,3 residual intellectual impairment, inattention/overactivity, disinhibited attachment, and quasi-autistic symptoms persisted in a substantial minority, at least up to the age of 11 years.1,2 The persistence of such effects, despite the radical and positive change in the children’s circumstances, suggests that they are mediated by fundamental neurobiological changes;4 a view consistent with the long-term pattern of reduced brain size in Romanian adoptees.4,5
These children were exposed to multiple putative risks in their institutions. Nutritional risk, associated with the very poor quality and quantity of food, was reflected in the large proportion of children with sub-nutrition on entry into the UK.6 Psychosocial risks, associated with social/emotional (e.g. low levels of social contact and emotional support, etc.) and intellectual deprivation (e.g. lack of stimulation because of extended confinement to cots, etc.) were, if anything, even more marked and pervasive.7 In the light of this, the primary aim of this paper was to partition overall institutional deprivation-related risks on cognitive, mental health, and brain-related outcomes, into sub-nutrition-related components as indexed by weight at entry to the UK and psychosocial components – indexed by duration of deprivation.
Our hypotheses were based on the clinical and experimental literature suggesting that both physical and psychosocial components of early deprivation are likely to influence negative outcomes. Sub-nutrition inhibits brain growth and development during the early years8–12 and is associated with both intellectual impairments and general mental health problems.13,14 The cognitive and behavioural effects of psychosocial components of deprivation are also well documented in clinical studies of patient populations4,15,16 and animal models17–19 in which environmental impoverishment is associated with brain size reductions, structure, and function, even when nutrition is adequate.
We hypothesized that both components of deprivation would increase risk across a broad range of outcomes following early institutional care. More specifically, this would mean that whereas sub-nutrition is expected to play an important role in deprivation-related effects, there would also be effects of deprivation duration on all outcomes, even in children who were not sub-nourished. Because sub-nutrition, even that lasting only a few months, may be expected to have major effects on body size (as indexed by height and weight), there is likely to be a concomitant impairment in brain growth (indexed by head circumference). By contrast, the effects of psychosocial deprivation on brain growth are not likely to operate via overall body size. Accordingly, we predicted that effects on brain growth would take longer to operate in the absence of sub-nutrition.
The children in our main sample all experienced some degree of deprivation in the Romanian institutions. However, crucially for the purposes of the current analysis, they differed greatly from one another in terms of the duration of deprivation they had experienced, with the length of time before entry into the UK ranging from 2 weeks to 3 years 7 months. Our published findings on outcomes at age 11,1,2 suggest that there is a threshold of risk associated with duration of deprivation operating in the first year. While children with less than 6 months deprivation appeared at no greater risk of poor outcomes than non-institutionalized UK adoptees, those with between 6 months and 3 years 7 months duration were at a substantially increased risk, though this risk did not increase with increasing time in the institutions within this group. In the absence of direct measures of nutritional care in the institutions or specific biological markers, in the current paper we estimated nutritional status on the basis of weight at the time of entry into UK indexed against population norms.
While sub-nutrition was extreme in many cases and was common in the sample, it was by no means universal; a substantial number of children, even among those suffering the longest periods of deprivation, had weights that were in the normal range and well above the cut-off used in previous studies.20,21 This indicates that these children at least received adequate calorific intake, although details were not available of their full nutritional status. The sample was, therefore, well placed to examine the effects of the contribution of duration of deprivation and sub-nutrition independently of one another and, furthermore, to establish whether in concert, any effects act additively or synergistically.
The question that follows, if we found that duration of deprivation and sub-nutrition were related to both head circumference and intellectual/mental health outcomes, as we predicted, is whether the postulated differences between sub-nutrition and psychosocial deprivation in the timing of effects on overall brain growth would have implications for psychological outcomes. If brain growth was a mediator of these broader outcomes, there might be long-term sequelae in sub-nourished children who left institutional care before the age of 6 months, but no such sequelae in children with similar duration of deprivation who were not sub-nourished. If institutional deprivation, independent of sub-nutrition, has effects on brain growth only when the deprivation lasts longer than 6 months, the question is whether impaired brain growth mediates negative cognitive and psychological effects of deprivation in this group also. In that regard, it is likely that sub-nutrition could operate mainly through effects on brain growth, whereas there is a broader range of possible mediators in the case of psychosocial deprivation. On this basis it might be predicted that brain growth is a stronger mediator in the case of sub-nutrition than where there is psychosocial deprivation in the absence of sub-nutrition.
- Top of page
As hypothesized, both psychosocial deprivation, even in the presence of normal overall nutrition, and, to a much lesser extent, sub-nutrition itself, predisposed to negative outcomes in a group of children with a history of institutional deprivation. These effects were also seen on brain growth as indexed by head circumference, but the timing of effects on head circumference was quite different for each risk factor. Among children whose institutional deprivation ceased at or before 6 months of age, sub-nutrition, nevertheless, was associated with a head circumference that was nearly 3SDs below the mean at the time of leaving institutional care. In sharp contrast, children without sub-nutrition who left institutions before the age of 6 months showed no significant reduction in head growth. On the other hand, if the children remained in institutional care for longer than 6 months, the reduction in head growth was very substantial and much the same in those with and without sub-nutrition. Clearly psychosocial deprivation can have major effects on head growth even in the absence of sub-nutrition.
The next question was whether impaired head growth played a mediating role in the broader range of psychological and psychopathological outcomes. Three findings provided initial indications that this might be the case. First, in the group with sub-nutrition whose deprivation lasted less than 6 months, there was both a major effect on head growth and a significant association with lower IQ. Neither effect was found in children without sub-nutrition. Second, impaired head growth at age 6 was associated with adverse effects on all outcomes at age 11 for the sample as a whole. Third, in the children both with and without sub-nutrition, the recovery in head growth was both limited (in comparison with weight) and more prolonged (with continuing gains made between 6 and 11y of age). Finally, sub-nutrition had a strong effect on head circumference both at the time of leaving institutional care and at age 11; multivariate analyses indicated that duration of deprivation also had a strong effect at both ages, but the effects of sub-nutrition were somewhat greater. In spite of that, whereas duration of deprivation had a strong effect on all psychological and psychopathological outcomes, the effects of sub-nutrition were far weaker and reached statistical significance only in the case of IQ after controlling for multiple testing.
Mediational analyses with the full sample provided very limited support for a role of head circumference mediating the link between duration of deprivation and outcomes at 11 with only a suggestion of an effect in relation to IQ. However, supplementary analysis of the effects within the sub-nutrition and non-sub-nutrition sub-groups suggested that mediation may be occurring but only for certain groups of children. The pattern of results as a whole is complex and the effects in general small so one must be cautious not to over-interpret them, especially given the small cell sizes and associated lack of power. For IQ, duration of deprivation is implicated to a far greater degree where sub-nutrition is not a factor, but head circumference seems to play a bigger mediating role where sub-nutrition is a factor. For inattention/overactivity and disinhibited attachment the results were in the opposite direction with the possible mediating effects being shown in the non-sub-nourished groups. This suggests that the underlying processes linking deprivation to cognitive outcomes might be somewhat different from those linking them to other deprivation specific outcomes.
The findings on head growth (and, by implication, on brain growth) provide some of the strongest clinical evidence to date that psychosocial deprivation, in the absence of sub-nutrition, can have a major long-term effect on brain development. However, as discussed above, rather surprisingly, the findings suggest a limited and complex role for head circumference in mediating deprivation related outcomes. Such findings necessarily raise the question whether head circumference provides an adequate index of brain growth. The evidence from other research suggests that the two are fairly closely associated, and our own findings (on a sub-sample) showed the same: brain growth is the main driver of head growth. Does the rather scant evidence for a mediating role of head circumference for outcomes mean that alterations in brain development are not involved in psychological and psychopathological sequelae of deprivation? Obviously not: overall brain size provides little direct indication of the more subtle alterations in brain structure and function, and underlying neurochemical processes, that are likely to be implicated in the functional deficits associated with institutional deprivation in this sample. Such alterations are perhaps likely to be especially important for the effects of psychosocial deprivation on mental health outcomes. Initial pilot data using magnetic resonance imaging technology have shown structural alterations in the amygdala of the ERA children.5 These findings suggest a potential role of early stress exposure in the developmental pathophysiology of institutional deprivation and a large-scale study of stress reactivity, brain structure, and function and development in the ERA sample is currently being planned. Given the suggestion of differential patterns of mediation as a function of nutritional status, it will be important in future studies to identify whether there are differential patterns of structural and functional brain alteration in relation to IQ in these two groups.
A further query needs to be raised on the apparently relatively minor effect of sub-nutrition on psychological and psychopathological outcomes, despite the strong effect on both body weight and head circumference. There can be no doubt about the reality of nutritional deficiencies in our sub-sample of sub-nourished children. Equally, we have been extremely careful to define sub-nutrition in such a way as to be confident as possible that the overall caloric intake of the group without sub-nutrition was adequate; their near normal body weight attests to that fact. What is much less clear is whether the overall balance of their nutritional intake was satisfactory. It is possible that a nutritional imbalance played some role in the effects of psychosocial deprivation even though overall sub-nutrition did not.
As far as IQ, and to a lesser extent inattention/overactivity, are concerned, the largely independent effects of sub-nutrition and of duration of deprivation suggests that their risk effects may be underpinned by different mechanisms. Candidate mechanisms for nutrition-related effects include reduced overall processing capacity,39 and cognitive-energetic resources,40 whereas psychosocial effects may involve some form of biological programming during a critical period of early development. Rutter and O’Connor4 suggested that either experience-expectant (whereby certain experiences are required for normal development) or experience-adaptive (the brain adapts to the circumstances operating during critical periods) mechanisms could be involved. Distinguishing these effects is beyond the scope of the current study.
The current study had a number of limitations. First, direct indices of social and cognitive impoverishment in the institutions were not available because valid contemporaneous measures of the quality of the institutional environments were usually not possible.7 Second, it was not possible to obtain measures on the quality and quantity of food provided in the institutions; we had to rely on weight at entry as our proxy for sub-nutrition. Third, we know that some children moved from one institution to another and we have no satisfactory indices of the relative qualities of the different institutions and especially how these related to changing patterns of nutritional intake. For instance, it is possible that the presence of sub-nutrition early on in life may be masked in this study if a child moved from an institution with poor physical care to one with adequate care some time before leaving institutional care altogether and entering the UK.
In summary, the current study provides evidence for the effects of both sub-nutrition and psychosocial deprivation on long-term psychological and psychopathological development. However, the strength of effect of duration of psychosocial deprivation was substantially greater than that of sub-nutrition. The most striking finding was the major effect of psychosocial deprivation on head growth even in the absence of sub-nutrition; and the most striking negative finding was that, despite the apparent centrality of head circumference effects, these had no detectable mediating role of head circumference on other outcomes.