Cognitive impairment as a mediator in the developmental pathway from infant malnutrition to adolescent depressive symptoms in Barbadian youth.

OBJECTIVE

Depressive symptoms are elevated in adolescents who experienced significant malnutrition early in life. Early malnutrition can also have a significant impact on cognitive functioning, presumably because of the adverse impact of the malnutrition on the very young brain. In the context of a developmental cascade model, we tested the hypothesis that the association between early malnutrition and adolescent depressive symptoms is mediated by the cognitive impairment that ensues from the malnutrition.

METHODS

We evaluated Barbadian youth (N = 57) hospitalized for moderate to severe protein-energy malnutrition in the first year of life and healthy controls (N = 60) longitudinally. The primary hypothesis was tested by multiple regression models.

RESULTS

After adjusting for covariates, early malnutrition predicted both cognitive functioning in childhood (IQ, p < .001; attention problems, p < .01; Common Entrance Examination, p < .01; and adolescent depressive symptoms, p < .05). Childhood cognitive functioning mediated the association between early malnutrition and depressive symptoms in adolescence (p < .001). Maternal depressive symptoms were a significant but independent predictor of adolescent depressive symptoms (p < .05).

CONCLUSIONS

Cognitive compromise in childhood accounts indirectly for elevated depressive symptoms in previously malnourished adolescents, consistent with a developmental cascade model. The direct link between malnutrition and depressive symptoms in adolescence is small.