Association of Preterm Birth and Socioeconomic Status With Neonatal Brain Structure

Abstract

ImportancePreterm birth and socioeconomic status (SES) are associated with brain structure in childhood, but the relative contributions of each during the neonatal period are unknown.ObjectiveTo investigate associations of birth gestational age (GA) and SES with neonatal brain morphology by testing 3 hypotheses: GA and SES are associated with brain morphology; associations between SES and brain morphology vary with GA; and associations between SES and brain structure and morphology depend on how SES is operationalized.Design, Setting, and ParticipantsThis cohort study recruited participants from November 2016 to September 2021 at a single center in the United Kingdom. Participants were 170 extremely and very preterm infants and 91 full-term or near-term infants. Exclusion criteria were major congenital malformation, chromosomal abnormality, congenital infection, cystic periventricular leukomalacia, hemorrhagic parenchymal infarction, and posthemorrhagic ventricular dilatation.ExposuresBirth GA and SES, operationalized at the neighborhood level (using the Scottish Index of Multiple Deprivation), the family level (using parental education and occupation), and subjectively (World Health Organization Quality of Life measure).Main Outcomes and MeasuresBrain volume (85 parcels) and 5 whole-brain cortical morphology measures (gyrification index, thickness, sulcal depth, curvature, surface area) at term-equivalent age (median [range] age, 40 weeks, 5 days [36 weeks, 2 days to 45 weeks, 6 days] and 42 weeks [38 weeks, 2 days to 46 weeks, 1 day] for preterm and full-term infants, respectively).ResultsParticipants were 170 extremely and very preterm infants (95 [55.9%] male; 4 of 166 [2.4%] Asian, 145 of 166 [87.3%] White) and 91 full-term or near-term infants (50 [54.9%] male; 3 of 86 [3.5%] Asian, 78 of 86 [90.7%] White infants) with median (range) birth GAs of 30 weeks, 0 days (22 weeks, 1 day, to 32 weeks, 6 days) and 39 weeks, 4 days (36 weeks, 3 days, to 42 weeks, 1 day), respectively. In fully adjusted models, birth GA was associated with a higher proportion of brain volumes (27 of 85 parcels [31.8%]; β range, −0.20 to 0.24) than neighborhood-level SES (1 of 85 parcels [1.2%]; β = 0.17 [95% CI, −0.16 to 0.50]) or family-level SES (maternal education: 4 of 85 parcels [4.7%]; β range, 0.09 to 0.15; maternal occupation: 1 of 85 parcels [1.2%]; β = 0.06 [95% CI, 0.02 to 0.11] respectively). There were interactions between GA and both family-level and subjective SES measures on regional brain volumes. Birth GA was associated with cortical surface area (β = 0.10 [95% CI, 0.02 to 0.18]) and gyrification index (β = 0.16 [95% CI, 0.07 to 0.25]); no SES measure was associated with cortical measures.Conclusions and RelevanceIn this cohort study of UK infants, birth GA and SES were associated with neonatal brain morphology, but low GA had more widely distributed associations with neonatal brain structure than SES. Further work is warranted to elucidate the mechanisms underlying the association of both GA and SES with early brain development.

Lifetime influences on imaging markers of adverse brain health and vascular disease

“…SES outcomes are reflected in brain structure and function as early as the neonatal period, with effects possibly augmenting throughout early childhood as a result of postnatal experiences [20] . Higher SES is associated with larger regional brain volumes in neonates after adjustment for prematurity, with family level measures such as income and parental education having stronger associations with brain morphology than neighbourhood deprivation at that stage [21] . In childhood and early adulthood, lower family income is associated with smaller white and grey matter volumes [22] and poorer white matter integrity [ 23 , 24 ].…”

Cerebral Small Vessel Disease: Early-Life Antecedents and Long-Term Implications for the Brain, Aging, Stroke, and Dementia

“…Socioeconomic disadvantage in childhood shapes neurodevelopmental and health outcomes from birth onward. 78 , 79 In childhood, brain structure mediates the relationship between SES and measures of function (eg, language, attention, and memory). 80 Children from higher SES households have access to more social and economic resources, which promote healthy development including cognitively stimulating home environments, healthier nutrition, and more stable living conditions.…”

“…Measurement often varies between studies, and if only 1 measurement is considered, it may not always capture the full socioeconomic position of the individual. 79 Furthermore, SES is not stable across the life course, with upward and downward mobility. Socioeconomically disadvantaged children who experience upward mobility in adulthood have better health outcomes than other disadvantaged children with static or downward mobility, suggesting upward mobility can compensate for disadvantage in childhood.…”

Neuroprotective therapies in the NICU in preterm infants: present and future (Neonatal Neurocritical Care Series)

“…Lower maternal education as a proxy for SES has been widely studied in this context, perceptions of neighborhood safety and the maternal vulnerability index, a composite measure that reflects physical, social, and health care needs, have also been associated with preterm birth, less use of prenatal care and poorer long-term outcomes. 219 , 220 While the mechanisms underlying these associations are not fully elucidated, these findings suggest that strategies improving social determinants of health for premature infants may have a positive effect on their long-term health and neurodevelopmental outcomes 221 and that, as such, advocacy by clinicians in this area is vital.…”