Peer Relationship Trajectories in Very Preterm and Term Individuals from Childhood to Early Adulthood

Participation in club sport in childhood is associated with mental health in preterm and term born adolescents

Preterm born individuals have an increased risk for mental health problems. Participation in club sport is associated with better mental health but the causal direction is unclear. It is not known whether this association could also be found in preterm children. Data from term born (N = 10,368), late preterm (N = 630), and very to moderately preterm born (N = 243) children from the Millennium Cohort Study at the ages of 3, 5, 7, 11, and 14 years were used. Longitudinal associations between the parent-reported Strengths and Difficulties questionnaire (SDQ) and club sport participation (days per week) were analysed using multigroup structural equation modelling, adjusting for gender, maternal depression, parental education; motor problems and attrition were controlled for. Multi-group structural equation modelling showed that children with more peer relationship problems, emotional symptoms, conduct problems or hyperactivity-inattention were less likely to participate in club sport at subsequent assessment time points. More days with club sport participation was associated with lower levels of emotional symptoms and peer relationship problems but not conduct problems or hyperactivity-inattention at subsequent ages. Results were similar in all gestational age groups. Club sport participation predicts lower levels of peer relationship and emotional problems in subsequent waves while it is also predicted by lower levels of emotional problems, peer relationship problems, conduct problems and hyperactivity-inattention in preceding waves. Since no differences in the relationship between SDQ subscales and club sport participation were seen with regard to gestational age groups, club sport should be encouraged in all children.

Problems in peer relationships and low engagement in romantic relationships in preterm born adolescents: effects of maternal warmth in early childhood

This study examined whether maternal warmth in early childhood moderates the association between preterm birth and problems in peer relationships and low engagement in romantic relationships in adolescence. We studied 9193 individuals from the Millennium Cohort Study in the United Kingdom, 99 (1.1%) of whom were born very preterm (VPT; < 32 weeks of gestation) and 629 (6.8%) moderate-to-late preterm (MLPT; 32-36 weeks gestation). Maternal warmth was reported by the mothers when their children were 3 years old. Peer relationship problems were reported by both the participants and their mothers at 14 and 17 years. Further, participants reported their engagement in romantic relationships at 14 and 17 years. All outcome variables were z-standardized, and the moderation effect was examined via hierarchical linear regressions. Compared to full-term birth, both MLPT and VPT birth were associated with lower engagement in romantic relationships at 17 years of age (b = .04, p = .02; b = .11, p = .02, respectively), and VPT birth was associated with increased peer relationship problems at 14 (b = .29, p = .01) and 17 years of age (b = .22, p = .046). Maternal warmth in early childhood was similarly associated with lower peer relationship problems in MLPT, VPT and full-term born adolescents. However, there was no influence of maternal warmth on engagement in romantic relationships at 17 years of age. There is no major modifying effect of maternal warmth in early childhood on the association between PT birth and peer relationship problems and low engagement in romantic relationships at 14 and 17 years of ages.

Altered gray-to-white matter tissue contrast in preterm-born adults

AIMS

To investigate cortical organization in brain magnetic resonance imaging (MRI) of preterm-born adults using percent contrast of gray-to-white matter signal intensities (GWPC), which is an in vivo proxy measure for cortical microstructure.

METHODS

Using structural MRI, we analyzed GWPC at different percentile fractions across the cortex (0%, 10%, 20%, 30%, 40%, 50%, and 60%) in a large and prospectively collected cohort of 86 very preterm-born (<32 weeks of gestation and/or birth weight <1500 g, VP/VLBW) adults and 103 full-term controls at 26 years of age. Cognitive performance was assessed by full-scale intelligence quotient (IQ) using the Wechsler Adult Intelligence Scale.

RESULTS

GWPC was significantly decreased in VP/VLBW adults in frontal, parietal, and temporal associative cortices, predominantly in the right hemisphere. Differences were pronounced at 20%, 30%, and 40%, hence, in middle cortical layers. GWPC was significantly increased in right paracentral lobule in VP/VLBW adults. GWPC in frontal and temporal cortices was positively correlated with birth weight, and negatively with duration of ventilation (p < 0.05). Furthermore, GWPC in right paracentral lobule was negatively correlated with IQ (p < 0.05).

CONCLUSIONS

Widespread aberrant gray-to-white matter contrast suggests lastingly altered cortical microstructure after preterm birth, mainly in middle cortical layers, with differential effects on associative and primary cortices.

Developmental Cascades Link Maternal-Newborn Skin-to-Skin Contact with Young Adults' Psychological Symptoms, Oxytocin, and Immunity; Charting Mechanisms of Developmental Continuity from Birth to Adulthood

Premature birth disrupts the continuity of maternal-newborn bodily contact, which underpins the development of physiological and behavioral support systems. Utilizing a unique cohort of mother-preterm dyads who received skin-to-skin contact (Kangaroo Care, KC) versus controls, and following them to adulthood, we examined how a touch-based neonatal intervention impacts three adult outcomes; anxiety/depressive symptoms, oxytocin, and secretory immunoglobulin A (s-IgA), a biomarker of the immune system. Consistent with dynamic systems' theory, we found that links from KC to adult outcomes were indirect, mediated by its effects on maternal mood, child attention and executive functions, and mother-child synchrony across development. These improvements shaped adult outcomes via three mechanisms; (a) "sensitive periods", where the infancy improvement directly links with an outcome, for instance, infant attention linked with higher oxytocin and lower s-IgA; (b) "step-by-step continuity", where the infancy improvement triggers iterative changes across development, gradually shaping an outcome; for instance, mother-infant synchrony was stable across development and predicted lower anxiety/depressive symptoms; and (c) "inclusive mutual-influences", describing cross-time associations between maternal, child, and dyadic factors; for instance, from maternal mood to child executive functions and back. Findings highlight the long-term impact of a birth intervention across development and provide valuable insights on the mechanisms of "developmental continuity", among the key topics in developmental research.

Altered Gray Matter Cortical and Subcortical T1-Weighted/T2-Weighted Ratio in Premature-Born Adults

BACKGROUND

Microscopic studies in newborns and animal models indicate impaired myelination after premature birth, particularly for cortical myelination; however, it remains unclear whether such myelination impairments last into adulthood and, if so, are relevant for impaired cognitive performance. It has been suggested that the ratio of T1-weighted (T1w) and T2-weighted (T2w) magnetic resonance imaging signal intensity (T1w/T2w ratio) is a proxy for myelin content. We hypothesized altered gray matter (GM) T1w/T2w ratio in premature-born adults, which is associated with lower cognitive performance after premature birth.

METHODS

We analyzed GM T1w/T2w ratio in 101 adults born very premature (VP) and/or at very low birth weight (VLBW) (<32 weeks of gestation and/or birth weight <1500 g) and 109 full-term control subjects at 26 years of age, controlled for voxelwise volume alterations. Cognitive performance was assessed by verbal, performance, and full scale IQ using the Wechsler Adult Intelligence Scale.

RESULTS

Significantly higher T1w/T2w ratio in VP/VLBW subjects was found bilaterally in widespread cortical areas, particularly in frontal, parietal, and temporal cortices, and in putamen and pallidum. In these areas, T1w/T2w ratio was not related to birth variables, such as gestational age, or IQ scores. In contrast, significantly lower T1w/T2w ratio in VP/VLBW subjects was found in bilateral clusters in superior temporal gyrus, which was associated with birth weight in the VP/VLBW group. Furthermore, lower T1w/T2w ratio in left superior temporal gyrus was associated with lower full scale and verbal IQ.

CONCLUSIONS

Results demonstrate GM T1w/T2w ratio alterations in premature-born adults and suggest altered GM myelination development after premature birth with lasting and functionally relevant effects into early adulthood.

Aberrant allometric scaling of cortical folding in preterm-born adults

A universal allometric scaling law has been proposed to describe cortical folding of the mammalian brain as a function of the product of cortical surface area and the square root of cortical thickness across different mammalian species, including humans. Since these cortical properties are vulnerable to developmental disturbances caused by preterm birth in humans and since these alterations are related to cognitive impairments, we tested (i) whether cortical folding in preterm-born adults follows this cortical scaling law and (ii) the functional relevance of potential scaling aberrances. We analysed the cortical scaling relationship in a large and prospectively collected cohort of 91 very premature-born adults (<32 weeks of gestation and/or birthweight <1500 g, very preterm and/or very low birth weight) and 105 full-term controls at 26 years of age based on the total surface area, exposed surface area and average cortical thickness measured with structural magnetic resonance imaging and surface-based morphometry. We found that the slope of the log-transformed cortical scaling relationship was significantly altered in adults (very preterm and/or very low birth weight: 1.24, full-term: 1.14, P = 0.018). More specifically, the slope was significantly altered in male adults (very preterm and/or very low birth weight: 1.24, full-term: 1.00, P = 0.031), while there was no significant difference in the slope of female adults (very preterm and/or very low birth weight: 1.27, full-term: 1.12, P = 0.225). Furthermore, offset was significantly lower compared with full-term controls in both male (very preterm and/or very low birth weight: -0.546, full-term: -0.538, P = 0.001) and female adults (very preterm and/or very low birth weight: -0.545, full-term: -0.538, P = 0.023), indicating a systematic shift of the regression line after preterm birth. Gestational age had a significant effect on the slope in very preterm and/or very low birth weight adults and more specifically in male very preterm and/or very low birth weight adults, indicating that the difference in slope is specifically related to preterm birth. The shape or tension term of the scaling law had no significant effect on cognitive performance, while the size of the cortex did. Results demonstrate altered scaling of cortical surface and cortical thickness in very premature-born adults. Data suggest altered mechanical forces acting on the cortex after preterm birth.

Large-scale brain network dynamics in very preterm children and relationship with socio-emotional outcomes: an exploratory study

BACKGROUND

Children born very preterm (VPT; <32 weeks' gestation) are at high risk of neurodevelopmental and behavioural difficulties associated with atypical brain maturation, including socio-emotional difficulties. The analysis of large-scale brain network dynamics during rest allows us to investigate brain functional connectivity and its association with behavioural outcomes.

METHODS

Dynamic functional connectivity was extracted by using the innovation-driven co-activation patterns framework in VPT and full-term children aged 6-9 to explore changes in spatial organisation, laterality and temporal dynamics of spontaneous large-scale brain activity (VPT, n = 28; full-term, n = 12). Multivariate analysis was used to explore potential biomarkers for socio-emotional difficulties in VPT children.

RESULTS

The spatial organisation of the 13 retrieved functional networks was comparable across groups. Dynamic features and lateralisation of network brain activity were also comparable for all brain networks. Multivariate analysis unveiled group differences in associations between dynamical functional connectivity parameters with socio-emotional abilities.

CONCLUSION

In this exploratory study, the group differences observed might reflect reduced degrees of maturation of functional architecture in the VPT group in regard to socio-emotional abilities. Dynamic features of functional connectivity could represent relevant neuroimaging markers and inform on potential mechanisms through which preterm birth leads to neurodevelopmental and behavioural disorders.

IMPACT

Spatial organisation of the retrieved resting-state networks was comparable between school-aged very preterm and full-term children. Dynamic features and lateralisation of network brain activity were also comparable across groups. Multivariate pattern analysis revealed different patterns of association between dynamical functional connectivity parameters and socio-emotional abilities in the very preterm and full-term groups. Findings suggest a reduced degree of maturation of the functional architecture in the very preterm group in association with socio-emotional abilities.

Molding influences of prematurity: Interviews with adults born preterm

BACKGROUND

Tremendous medical advancements over the last several decades have supported the survival of younger and sicker newborns. Substantial quantitative research exists about health and developmental outcomes following preterm birth, however, limited published literature has explored what this experience means to the survivors.

AIM

The purpose was to describe, interpret and understand how adults born preterm perceive prematurity to have affected their lives.

STUDY DESIGN

Qualitative thematic analysis.

METHODS

Semi-structured interviews were conducted with 33 adults born preterm from the RHODĒ Study, a longitudinal preterm birth cohort. A cross-section of participants with high and low early life medical and environmental risk was interviewed. Data were analyzed using a constructionist method of latent theme analysis.

RESULTS

From the data, 3 themes were identified: 1) My parents call me their miracle, 2) It's not a big deal, I'm the same as everyone else, 3) I've overcome a lot. Themes represent a continuum of experience, from positive to neutral to negative. Common life experiences of family, education, friends, and health are subthemes that help to illuminate how participants assign meaning to their prematurity. Meaning was linked to how typical or not participants perceive their health, learning and friends compared to peers.

CONCLUSION

Perceptions about prematurity and adversity are influenced by the ways parents and families represent prematurity in shared stories and actions. These findings should inform future research with adult survivors of prematurity. Participants identified ongoing need for support and advocacy, particularly from healthcare and education communities.

The Impact of Formal School Entry on Children's Social Relationships with Parents, Siblings, and Friends

The normative transition to formal schooling confronts children with social challenges but also opportunities. Longitudinal research on how school entry impacts children's family and friend-ship relationships is scarce. This study investigated social relationship qualities with parents, siblings, and friends among 1110 children (49.9% female) from the prospective, population-based Bavarian Longitudinal Study at 6 years (before school entry) and 8 years using a forced-choice card-sorting task. Multivariate analyses of variance revealed significant effects of age (i.e., school entry) on social relationship qualities with mothers (Pillai's Trace (PT) = 0.28, F(9, 1101) = 47.73, p < 0.001), fathers (PT = 0.14, F(9, 1101) = 19.47, p < 0.001), siblings (PT = 0.27, F(9, 1101) = 46.14, p < 0.001), and friends (PT = 0.21, F(9, 1101) = 32.57, p < 0.001). On average, children reported higher levels of parental comfort after school entry. Companionable qualities increased in relationships with friends, whereas sibling relationships became more conflictual from preschool to early school age. Findings provide unique insights into how social relationships develop from preschool to early school age, supporting evidence of the growing importance of friends. Conflict was predominant and increasing in sibling relationships and should be considered more in future research.

Within amygdala: Basolateral parts are selectively impaired in premature-born adults

While it is known that whole amygdala volume is lastingly reduced after premature birth, it is unknown whether different amygdala nuclei are distinctively affected by prematurity. This question is motivated by two points: First, the observation that developmental trajectories of superficial, centromedial and basolateral amygdala nuclei are different. And second, the expectation that these different developmental pathways are distinctively affected by prematurity. Furthermore, we stated the question whether alterations in amygdala nuclei are associated with increased adults' anxiety traits after premature birth. We investigated 101 very premature-born adults (<32 weeks of gestation and/or birth weight below 1500 g) and 108 full-term controls of a prospectively and longitudinally collected cohort at 26 years of age using automated amygdala nuclei segmentation based on structural MRI. We found selectively reduced volumes of bilateral accessory basal nuclei (pertaining to the basolateral amygdala of claustral developmental trajectory) adjusted for whole amygdala volume. Volumes of bilateral accessory basal nuclei were positively associated with gestational age and negatively associated with duration of ventilation. Furthermore, structural covariance within the basolateral amygdala was increased in premature-born adults. We did not find an association between reduced volumes of basolateral amygdala and increased social anxiety in the prematurity group. These results demonstrate specifically altered basolateral amygdala structure in premature-born adults. Data suggest that prematurity has distinct effects on amygdala nuclei.