Nutrition in Middle Childhood and Externalizing and Internalizing Problems in Adolescence:\nResults from the Bogota School Children Cohort

Field: Medicine (Health Sciences)

Background. An optimal diet is essential for adequate neurodevelopment. Behavior problems during adolescence are highly prevalent and result in adverse health outcomes in the short- and long-term. The role of middle childhood diet on adolescent behavior problems is uncertain. \n\n Objectives. We examined the associations of the following dietary exposures in middle childhood with externalizing and internalizing behavior problems in adolescence: 1) iron deficiency (ID) and anemia, 2) vitamin D deficiency (VDD) and vitamin D binding protein (DBP) concentrations, and 3) serum n-3 and n-6 polyunsaturated fatty acid (PUFA) concentrations.\n\n Methods. These studies take place in the context of the Bogota School Children Cohort (BoSCCo), a longitudinal investigation of nutrition and health in Bogota, Colombia. Three thousand two hundred and two schoolchildren, aged 5-12 y, were recruited into BoSCCo from primary public schools in February, 2006. Upon recruitment, parents completed a background survey on family sociodemographic information and the health habits of their child. Research assistants obtained a baseline fasting blood sample from 88% of the children. After a median 6 y, total externalizing and internalizing behavior problems and their subscales (aggressive behavior, rule breaking behavior, anxious/depressed, withdrawn/depressed, and somatic complaints) were assessed with use of the Youth Self Report in a random sample of approximately one-third of the cohort. \n We assessed whether ID (ferritin <15 µg/L when C-reactive protein ≤10 mg/L), anemia (hemoglobin <12.7 g/dL) or blood concentrations of zinc, vitamins A and B-12, and erythrocyte folate in middle childhood were associated with behavior problems in adolescence in 1,042 schoolchildren. The associations between middle childhood VDD (25-hydroxy vitamin D <50 nmol/L) or low DBP concentration (<2497 nmol/L) and adolescent behavior problems were examined in 278 schoolchildren. Finally, we investigated the relations between PUFA concentrations in middle childhood and behavior problems in adolescence among 444 schoolchildren.\n In bivariate analysis, behavior problems score distributions were compared across levels of potential confounding variables measured at baseline. Then, the continuous distributions of behavior problems scores were compared across categories of each of the nutritional exposures of interest. Mean differences in behavior problems scores were estimated by categories of nutritional exposures with the use of multivariable linear regression. \n\n Results. After controlling for potential confounding variables, ID, anemia, and low vitamin B-12 in middle childhood were each positively related to total externalizing problems scores among boys. In addition, ID was positively related to total internalizing problems scores among boys. Middle childhood VDD was positively associated with total externalizing problems scores while low DBP was positively related to aggressive behavior and anxious/depressed scores. Docosapentaenoic acid was inversely associated with total externalizing problems scores whereas docosahexaenoic acid was positively associated with this outcome. In addition, the Δ5-desaturase enzyme activity index was inversely related to total externalizing problems scores. Alpha-linolenic acid was positively associated with total internalizing problems scores whereas adrenic acid was inversely related to this outcome. \n\n Conclusions and significance. Nutrition in middle childhood was associated with behavior problems in adolescence. Adolescents with externalizing and internalizing problems are at high risk for psychiatric disorders in adulthood. In a country that has experienced over 50 years of civil war, the long-term consequences of behavior problems may be of critical public health concern. These studies could provide a basis for the planning of nutritional intervention studies.