Maternal education and cognitive development in 15 European very-preterm birth cohorts from the RECAP Preterm platform

Abstract

Background Studies are sparse and inconclusive about the association between maternal education and cognitive development among children born very preterm (VPT). Although this association is well established in the general population, questions remain about its magnitude among children born VPT whose risks of medical and developmental complications are high. We investigated the association of maternal education with cognitive outcomes in European VPT birth cohorts. Methods We used harmonized aggregated data from 15 population-based cohorts of children born at <32 weeks of gestational age (GA) or <1500 g from 1985 to 2013 in 13 countries with information on maternal education and assessments of general development at 2–3 years and/or intelligence quotients between 4 and 15 years. Term-born controls (≥37 weeks of GA) were available in eight cohorts. Maternal education was classified as: low (primary/lower secondary); medium (upper secondary/short tertiary); high (bachelor’s/higher). Pooled standardized mean differences (SMDs) in cognitive scores were estimated (reference: high educational level) for children assessed at ages 2–3, 4–7 and 8–15 years. Results The study included 10 145 VPT children from 12 cohorts at 2–3 years, 8829 from 12 cohorts at 4–7 years and 1865 children from 6 cohorts at 8–15 years. Children whose mothers had low, compared with high, educational attainment scored lower on cognitive measures [pooled unadjusted SMDs: 2–3 years = −0.32 (95% confidence intervals: −0.43 to −0.21); 4–7 years = −0.57 (−0.67; −0.47); 8–15 years = −0.54 (−0.72; −0.37)]. Analyses by GA subgroups (<27 vs ≥27 weeks) in children without severe neonatal morbidity and term controls yielded similar results. Conclusions Across diverse settings and regardless of the degree of prematurity, low maternal education was associated with lower cognition.

Management and outcomes of extreme preterm birth

“… 3 For example, a recent meta-analysis of European preterm cohorts showed that, compared with families where mothers had a bachelors or higher degree, standardised mean differences of cognitive scores for children born extremely preterm were 0.24 (95% CI 0.02 to 0.46) lower in families where mothers had an upper secondary or short tertiary level of education, and 0.57 (95% CI 0.34 to 0.76) lower when mothers had only primary or lower secondary education. 20 …”

The challenges of heterogeneity in gestational age and birthweight inclusion criteria for research synthesis on very preterm birth and childhood cognition: An umbrella review and meta‐regression analysis

“…The GA/BW inclusion criteria in these studies were highly varied as shown in Table 2 with 27 different combinations. The most common were BW <1500 g (24 cohorts), GA <32 weeks (12), GA <33 weeks (12) and BW<1000 grams (12). Few cohorts (2) had GA <28 weeks as an inclusion criterion.…”

“…11 This is of concern because disadvantaged families face higher risks of VPT birth 11 and social disadvantage is associated with worse long-term cognitive outcomes. 12 Systematic reviews have adopted different approaches, with some including all studies based on GA and/or BW, while others have aimed to reduce heterogeneity by selecting only studies that used GA inclusion criteria. In a review of five systematic reviews with metaanalyses on the topic of VPT birth and cognition, we previously showed that investigators' methodological choices with regard to inclusion and exclusion criteria for primary studies resulted in minimal overlap in the included studies across systematic reviews.…”

The extremely preterm young adult – State of the art

“…In addition, markers of neonatal morbidity such as supplemental oxygen use at 28 days/36 weeks postmenstrual age and the ultrasound identification of preterm brain injury were also associated with a 2-3 point decrement in IQ. In a separate meta-analysis, the effect of maternal education produced a consistent effect at different ages and in different gestational groups [2]. Reflecting the birth years of the cohorts (1978)(1979)(1980)(1981)(1982)(1983)(1984)(1985)(1986)(1987)(1988)(1989)(1990)(1991)(1992)(1993)(1994)(1995), the mean age at assessment ranged from 19 to 30 years.…”