Cognition, behavior and social competence of preterm low birth weight children at school age

Abstract

Objective: The aim of this study was to assess the cognitive and behavioral development of preterm and low birth weight newborns living in a disadvantageous socioeconomic environment at school age.

Methods: This cross-sectional study included children aged 6-7 from a historical birth cohort of preterm (gestational age <37 weeks) and low birth weight (<2,500 g) infants. The Wechsler Intelligence Scale for Children III (WISC-III) was administered by a psychologist while the parents completed the Child Behavior Checklist. The results were compared to the test's reference. The perinatal information and follow-up data were collected from the hospital files. The demographic data were collected from the parents. The current performance was compared with the results from the Denver II and Bayley II tests, which were administered during the first years of life.

Results: The total intelligence quotient varied from 70 to 140 (mean 98.7±15.8). The borderline intelligence quotient was observed in 9.3% of the children. The Child Behavior Checklist indicated a predominance of social competence problems (27.8%, CI 19.2 to 37.9) compared with behavioral problems (15.5%, CI 8.9 to 24.2). Both the Child Behavior Checklist domains, such as schooling, social and attention problems, and the cognitive scores were significantly associated with maternal education and family income. The results of the Denver and Bayley tests were associated with the cognitive performance (p<0.001) and the Child Behavior Checklist social profile, including aggressive and externalizing behavior (p<0.001).

Conclusions: Our data suggest that even low-risk preterm newborns are at risk for developing disturbances in early school age, such as mild cognitive deficits and behavioral disorders. This risk might increase under unfavorable socioeconomic conditions.

Figure 1

Boxplot graphic for scores on the WISC-III subtests obtained in the study sample. The first six subtests comprise the verbal IQ, and the others comprise the executive IQ The data are presented as the mean ± standard deviation (SD), median, minimum (min), maximum (max) and percentage of observations below the cut-off point 7 (minimum value for normality).