Work

Maternal obesity, gestational weight gain, and offspring cognitive performance in adolescence

Year: 2017

Type: article

Abstract: Background Maternal obesity is a modifiable risk factor for perinatal outcomes. Maternal obesity and excessive gestational weight gain (GWG) are associated with adverse offspring neurodevelopment. This study investigates the association of maternal BMI at first antenatal visit, weight gained during pregnancy with offspring cognitive performance in adolescence. Methods Study design: Population based cohort study using linked register data Setting: 525850 non-adopted Swedish individuals, born 1982 to 1989, followed until December 31st 2011 Outcomes: Cognitive performance measured in two sub cohorts: by standardised school leaving grades (SLG) at 16 (n = 487145), and IQ score at conscription into Swedish army, age 18 (n = 168484, male only) Statistics: Random effects linear regression, adjusted for socioeconomic status and paternal IQ at 18. Family-based study designs were used to further test causality Results Maternal obesity (BMI ≥ 30) was associated with decreased SLG z-scores (BMI=36, -0.30; 95% CI, -0.32 to -0.27) and decreased stanine IQ score (BMI=36: -0.67; 95% CI -0.71 to -0.64) in adjusted models. Excessive GWG (>16kg for mothers with normal baseline BMI) was associated with decreased cognitive performance (SLG: GWG=21, -0.06; 95% CI -0.07 to -0.05), (IQ: GWG=21, -0.10, 95% CI -0.12 to -0.07). Paternal obesity at 18 was also associated with decreased cognitive performance (IQ, paternal BMI=36, -0.27, 95% CI -0.38 to -0.17, adjusted). Matched sibling analyses showed no association between maternal BMI, GWG and cognitive performance. Conclusions High maternal BMI and excessive GWG were associated with decreased offspring cognitive performance at 16 and 18 in full cohort, but not in sibling analyses, suggesting residual familial confounding. Paternal BMI at 18 was associated with decreased offspring cognition, implying genetic confounding. Maternal obesity and GWG are unlikely to be modifiable risk factors for offspring cognitive outcomes. Key messages: Maternal pre-pregnancy obesity and excessive GWG are associated with decreased offspring cognitive performance. This is likely due to familial and genetic confounding, and not modifiable risk factors.

Source: European Journal of Public Health

DOI: 10.1093/eurpub/ckx187.729