Head circumference at birth and school performance: a nationwide cohort study of 536,921 children

TY - JOUR

T1 - Head circumference at birth and school performance

T2 - a nationwide cohort study of 536,921 children

AU - Bach, Cathrine C

AU - Henriksen, Tine B

AU - Larsen, René T

AU - Aagaard, Kristina

AU - Matthiesen, Niels B

PY - 2020/5/1

Y1 - 2020/5/1

N2 - BACKGROUND: Early measures of cognitive function are of great public health interest. We aimed to estimate the association between head circumference at birth, a measure of cerebral size, and school performance.METHODS: We conducted a nationwide cohort study of all liveborn singletons in Denmark, 1997-2005. The association between birth head circumference z score and test scores in reading and mathematics from a nationwide mandatory computer-based school test program (7-16 years) was estimated by multivariable linear regression adjusted for potential confounders.RESULTS: The cohort included 536,921 children. Compared to normocephalic children, children with microcephaly [<-2 standard deviations (SD)] had lower mean reading scores: second grade: -0.08 SD (95% CI -0.10 to -0.06), eighth grade: -0.07 SD (95% CI -0.10 to -0.04). Macrocephaly (>+2 SD) was associated with higher scores. In normocephalic children, each SD increase in head circumference was associated with a 0.03 SD (95% CI 0.03 to 0.04) increase in mean reading scores. The results were similar across grades within both reading and mathematics.CONCLUSION: Prenatal brain growth may be causally related to childhood school performance. The demonstrated differences are unlikely to be clinically relevant at the individual level but may be important at a public health level.

AB - BACKGROUND: Early measures of cognitive function are of great public health interest. We aimed to estimate the association between head circumference at birth, a measure of cerebral size, and school performance.METHODS: We conducted a nationwide cohort study of all liveborn singletons in Denmark, 1997-2005. The association between birth head circumference z score and test scores in reading and mathematics from a nationwide mandatory computer-based school test program (7-16 years) was estimated by multivariable linear regression adjusted for potential confounders.RESULTS: The cohort included 536,921 children. Compared to normocephalic children, children with microcephaly [<-2 standard deviations (SD)] had lower mean reading scores: second grade: -0.08 SD (95% CI -0.10 to -0.06), eighth grade: -0.07 SD (95% CI -0.10 to -0.04). Macrocephaly (>+2 SD) was associated with higher scores. In normocephalic children, each SD increase in head circumference was associated with a 0.03 SD (95% CI 0.03 to 0.04) increase in mean reading scores. The results were similar across grades within both reading and mathematics.CONCLUSION: Prenatal brain growth may be causally related to childhood school performance. The demonstrated differences are unlikely to be clinically relevant at the individual level but may be important at a public health level.

U2 - 10.1038/s41390-019-0683-2

DO - 10.1038/s41390-019-0683-2

M3 - Journal article

C2 - 31779026

SN - 0031-3998

VL - 87

SP - 1112

EP - 1118

JO - Pediatric Research

JF - Pediatric Research

IS - 6

ER -