Head circumference in ELBW babies is associated with learning difficulties and cognition but not ADHD in the school‐aged child

Abstract

This study examines whether a small head circumference (HC) and low head‐circumference growth velocity (HGV) during the first year of life predict consequences at school age in learning, cognition, and concentration. A total of 124 extremely‐low‐birthweight (ELBW) infants (birthweight 500 to 999 g) born between 1977 and 1986 were eligible for follow‐up at the corrected ages of 4, 8, and 12 months and 2, 4, and 6 years. Infants were categorized as having a small HC (<3% or 3 to 10%) on the basis of the 1990 British growth data which allowed standardized z ‐scores to be calculated for HC, independent of gestation and corrected age. HGV measurements were calculated using differences in the HC z ‐scores. In 1995, parents of 87 children agreed to participate in a study of learning and attention at school age. Attention‐deficit–hyperactivity disorder (ADHD) was assessed using the Du Paul Rating Scale. Academic performances were based on a teacher questionnaire dealing with aspects of reading, writing, mathematics, and spelling. A child was considered to have a learning difficulty if academic problems were present in at least one of these four areas. Intellectual ability was assessed using the McCarthy Scale at 6 years. HC <3% and 3 to 10% at 8 months’corrected age was strongly associated with school‐aged learning problems (P=0.004), with a moderate specificity (70%), positive predictive value (PPV) (67%), and sensitivity (67%). HGV ?10% from birth to 4 months was also associated with learning problems at school age (P=0.01) with a higher specificity (98%) and PPV (88%) but lower sensitivity (20%). A logistic regression analysis was performed with the risk for