Prematurity and cardiovascular risk at early adulthood

Impact of sex, race, and social determinants of health on neonatal outcomes

Despite the global improvements in neonatal outcomes, mortality and morbidity rates among preterm infants are still unacceptably high. Therefore, it is crucial to thoroughly analyze the factors that affect these outcomes, including sex, race, and social determinants of health. By comprehending the influence of these factors, we can work towards reducing their impact and enhancing the quality of neonatal care. This review will summarize the available evidence on sex differences, racial differences, and social determinants of health related to neonates. This review will discuss sex differences in neonatal outcomes in part I and racial differences with social determinants of health in part II. Research has shown that sex differences begin to manifest in the early part of the pregnancy. Hence, we will explore this topic under two main categories: (1) Antenatal and (2) Postnatal sex differences. We will also discuss long-term outcome differences wherever the evidence is available. Multiple factors determine health outcomes during pregnancy and the newborn period. Apart from the genetic, biological, and sex-based differences that influence fetal and neonatal outcomes, racial and social factors influence the health and well-being of developing humans. Race categorizes humans based on shared physical or social qualities into groups generally considered distinct within a given society. Social determinants of health (SDOH) are the non-medical factors that influence health outcomes. These factors can include a person's living conditions, access to healthy food, education, employment status, income level, and social support. Understanding these factors is essential in developing strategies to improve overall health outcomes in communities.

Parental fructose consumption induces early baroreflex dysfunction in offspring: impact on arterial pressure and on insulin resistance

Fructose overconsumption is a worldwide trend, and it has been found to cause metabolic disorders in parents and their offspring. Additionally, metabolic syndrome has been closely associated with increased cardiovascular risk. In this study, we hypothesized that the chronic fructose consumption by parents could trigger autonomic dysfunction and cardiometabolic disorders in their offspring. Wistar rats undergo an intake of 10% of fructose in drinking water or regular water for 60 days before mating. Their offspring, control (C) and fructose (F) groups, were evaluated 30 days after weaning. Lower birth weight, increased levels of blood triglycerides and insulin resistance were observed in F compared to C group. The offspring of the fructose parents showed increased mean arterial pressure (C: 104 ± 1 vs. F: 111 ± 2 mmHg) and baroreflex sensitivity impairment, characterized by reduced bradycardic (C: -1.6 ± 0.06 vs. F: -1.3 ± 0.06 bpm/mmHg) and tachycardic responses (C: -4.0 ± 0.1 vs. F: -3.1 ± 0.2 bpm/mmHg). Finally, a higher baroreflex-induced tachycardia was associated with lower insulin tolerance (r = -0.55, P < 0.03) and higher systolic arterial pressure (r = 0.54, P < 0.02). In conclusion, our findings indicate that the excessive consumption of fructose by parents is associated with early autonomic, cardiovascular, and metabolic derangement in the offspring, favoring an increased cardiometabolic risk when they reach adulthood.

Effect of preterm birth on growth and blood pressure in adulthood in the Pelotas 1993 cohort

BACKGROUND

Preterm birth has been associated with increased risk of hypertension and cardiovascular disease later in adulthood, attributed to cardiovascular and metabolic alterations in early life. However, there is paucity of evidence from low- and middle-income countries (LMICs).

METHODS

We investigated the differences between preterm (<37 weeks gestational age) and term-born individuals in birth length and weight as well as adult (18 and 20 years) height, weight and blood pressure in the Brazilian 1993 Pelotas birth cohort using linear regressions. Analyses were adjusted for the maternal weight at the beginning of pregnancy and maternal education and family income at childbirth. Additional models were adjusted for body mass index (BMI) and birthweight. Separate analyses were run for males and females. The complete sample was analysed with an interaction term for sex.

RESULTS

Of the 3585 babies included at birth, 3010 were followed up in adulthood at 22 years. Preterm participants had lower length and weight at birth. This difference remained for male participants in adulthood, but female participants were no shorter than their term counterparts by 18 years of age. At 22 years, females born preterm had lower blood pressures (systolic blood pressure -1.00 mmHg, 95%CI -2.7, 0.7 mmHg; diastolic blood pressure -1.1 mmHg, 95%CI -2.4, 0.3 mmHg) than females born at term. These differences were not found in male participants.

CONCLUSIONS

In this Brazilian cohort we found contrasting results regarding the association of preterm birth with blood pressure in young adulthood, which may be unique to an LMIC.

Effect of preterm birth on blood pressure in later life: A systematic review and meta-analysis

Introduction

Preterm birth is linked to various complications in both infancy and adulthood. We assessed the association between preterm birth and hypertension in adulthood.

Materials and Methods

PubMed, EMBASE, and Cochrane CENTRAL Register were searched for randomized controlled trials (RCT) comparing systolic and diastolic blood pressures in individuals born preterm and those born full-term, from inception till April 11th, 2022. Data were extracted, pooled, and analyzed. Forest plots were created for a visual demonstration.

Results

Twenty-eight studies were included in our meta-analysis. SBP and DBP across all categories (Mean, Ambulatory, Daytime, and Nighttime) were higher in the preterm group compared to the term group. Mean SBP, mean ambulatory SBP, mean daytime SBP and mean nighttime SBP were 4.26 mmHg [95% CI: 3.09-5.43; P < 0.00001], 4.53 mmHg [95% CI: 1.82-7.24; P = 0.001], 4.51 mmHg [95% CI: 2.56-6.74; P < 0.00001], and 3.06 mmHg [95% CI: 1.32-4.80; P = 0.0006] higher in the preterm group, respectively. Mean DBP, mean ambulatory DBP, mean daytime DBP, and mean nighttime DBP were 2.32 mmHg [95% CI: 1.35-3.29; P < 0.00001], 1.54 mmHg [95% CI 0.68-2.39; P = 0.0004], 1.74 mmHg [95% CI: 0.92-2.56; P < 0.0001], and 1.58 mmHg [95% CI: 0.34-2.81; P = 0.01] higher in the preterm group, respectively.

Conclusion

Our observations suggest that individuals who were born preterm may have higher blood pressures as compared to those who were born full-term.

Accelerated Aging and the Life Course of Individuals Born Preterm

Individuals born preterm have shorter lifespans and elevated rates of chronic illness that contribute to mortality risk when compared to individuals born at term. Emerging evidence suggests that individuals born preterm or of low birthweight also exhibit physiologic and cellular biomarkers of accelerated aging. It is unclear whether, and to what extent, accelerated aging contributes to a higher risk of chronic illness and mortality among individuals born preterm. Here, we review accelerated aging phenotypes in adults born preterm and biological pathways that appear to contribute to accelerated aging. We highlight biomarkers of accelerated aging and various resiliency factors, including both pharmacologic and non-pharmacologic factors, that might buffer the propensity for accelerated aging among individuals born preterm.

Prematurity and Low Birth Weight and Their Impact on Childhood Growth Patterns and the Risk of Long-Term Cardiovascular Sequelae

Preterm birth (before 37 completed weeks of gestation) is a global health problem, remaining the main reason for neonatal mortality and morbidity. Improvements in perinatal and neonatal care in recent decades have been associated with a higher survival rate of extremely preterm infants, leading to a higher risk of long-term sequelae in this population throughout life. Numerous surveillance programs for formerly premature infants continue to focus on neurodevelopmental disorders, while long-term assessment of the impact of preterm birth and low birth weight on child growth and the associated risk of cardiovascular disease in young adults is equally necessary. This review will discuss the influence of prematurity and low birth weight on childhood growth and cardiovascular risk in children, adolescents and young adults. The risk of cardiovascular and metabolic disorders is increased in adult preterm survivors. In early childhood, preterm infants may show elevated blood pressure, weakened vascular growth, augmented peripheral vascular resistance and cardiomyocyte remodeling. Increased weight gain during the early postnatal period may influence later body composition, promote obesity and impair cardiovascular results. These adverse metabolic alterations contribute to an increased risk of cardiovascular incidents, adult hypertension and diabetes. Preterm-born children and those with fetal growth restriction (FGR) who demonstrate rapid changes in their weight percentile should remain under surveillance with blood pressure monitoring. A better understanding of lifelong health outcomes of preterm-born individuals is crucial for developing strategies to prevent cardiovascular sequelae and may be the basis for future research to provide effective interventions.

Association of Preterm Birth With Prevalent and Incident Hypertension, Early-Onset Hypertension, and Cardiovascular Disease in the Women's Health Initiative

Increasing evidence suggests preterm birth is a risk factor for hypertension and cardiovascular disease (CVD) in adulthood. Whether there is effect modification by hypertension on CVD risk is unknown. To investigate the associations between preterm birth, hypertension, and incident CVD, we identified 2,303 women aged 50 to 79 years who self-reported being born preterm from the Women's Health Initiative. Using multivariable logistic regression, prevalent hypertension at enrollment, age at hypertension diagnosis, and antihypertensive medication use were compared by birth status (preterm, full-term). Risk of incident hypertension, coronary heart disease, and CVD were analyzed using multivariable Cox proportional-hazard models. Both models adjusted for age, race/ethnicity, education, smoking, physical activity, body mass index, and diabetes mellitus. Significant associations were found between preterm birth and prevalent hypertension (37% vs 33.1%; adjusted odds ratio 1.26 [95% confidence interval (CI) 1.15 to 1.28] p = <0.0001), early-onset hypertension (<50 years) (14.7% vs 11.7%; adjusted odds ratio 1.31, 95% CI 1.15 to 1.48, p = <0.0001), and incident hypertension (53.2% vs 51%; ajusted hazard ratio 1.10, 95% CI 1.03 to 1.19, p = 0.008). Preterm-born women reported taking more antihypertensive medications (2.9% vs 2.6%, p = 0.04). Preterm birth had a nonsignificant association with CVD risk, but when stratified by prevalent hypertension, women born preterm without hypertension had elevated CVD risk compared with women born full-term without prevalent hypertension. Women with prevalent hypertension, preterm and full-term, had similar magnitudes of elevations in CVD risk. In conclusion, preterm birth increases the risk of hypertension and coronary heart disease. With 10% of the population born preterm, birth history should be assessed as a CVD risk factor.

Does recurrent gestational diabetes mellitus increase the risk of preterm birth? A population-based cohort study

AIMS

To investigate whether recurrent gestational diabetes mellitus (GDM) is associated with an increased risk of preterm birth.

METHODS

We conducted a prospective population-based cohort study covering all live singleton births born to nulliparous and multiparous mothers aged 20 years and older in Qingdao, from 2018 to 2020 (n = 105,528). Preterm birth (<37 gestational weeks) was classified into moderate preterm birth (32-36 weeks of gestation) and very preterm birth (<32 weeks). Logistic regression analysis was performed to estimate the risk and severity of prematurity in relation to parity among mothers with previous GDM, current GDM, and recurrent GDM (previous and current GDM), using mothers without GDM as the reference group. Z-test and ratio of odds ratios (ROR) were used to determine subgroup differences.

RESULTS

Maternal GDM increased the risk of preterm birth in both nullipara (OR_adj = 1.28, 95 %CI: 1.14-1.45) and multipara (OR_adj = 1.26, 95 %CI: 1.14-1.40). However, the risk of premature delivery in multiparous mothers with recurrent GDM and those with current GDM did not differ significantly, with a ROR of 0.89 (95 %CI: 0.71-1.12). The risk of recurrent GDM on preterm birth was most pronounced among multiparous mothers with pre-pregnancy BMI above 30 kg/m² (OR_adj = 2.18, 95 %CI: 1.25-3.82) as compared with those with current GDM alone (ROR = 2.20, 95 %CI: 1.07-4.52). The risk of GDM for moderate preterm birth was similar to that of overall preterm birth. In contrast, GDM was not associated with very preterm birth irrespective of parity (all P values > 0.05).

CONCLUSIONS

Maternal GDM increased the risk of preterm birth in nullipara and multipara, whereas recurrent GDM was not associated with a further increase in the risk of prematurity in multiparous mothers. Maternal GDM did not contribute to very preterm birth irrespective of parity. Our findings can be useful for facilitating more targeted preventive strategies for adverse pregnancy outcomes.

A test of differential susceptibility in behavior trajectories of preterm infants from preschool to adulthood

Preterm birth predisposes children to internalizing and externalizing behaviors that may persist into adolescence resulting in adult mental health conditions. Social and caregiving contexts, particularly for vulnerable infants born preterm, influence long-term outcomes, but mechanisms are not clearly understood. Healthcare teams caring for those born preterm face difficulty predicting who will be most affected by risk, who will most benefit, and the optimal timing of intervention. Differential susceptibility theory offers an alternative to the traditional risk-only assessments and theories by positing that individuals may be more, or less, susceptible to environmental influences. A sample of preterm- and term-born infants were followed from birth to 23 years of age. Mixed model repeated measures analyses of internalizing and externalizing behaviors were utilized for the comparison groups (N = 214; observations = 1070). Environmental contexts were indexed as proximal protection (low, moderate, high) and medical risk (low, moderate, high). Personal characteristic covariates of sex, race, socioeconomic status, and cognition were modeled. Internalizing behavior trajectories varied significantly over time. Early proximal protective environments conferred a sustained positive influence on behaviors. There is partial support for differential susceptibility theory suggesting that prematurity, as a malleability characteristic enables absorption of both the positive and negative influences of the environment, with greater intensity that those without malleability. The current analyses suggest lasting effects of the preschool age proximal environment on internalizing and externalizing behaviors in young adulthood for those born preterm. Understanding these nuances may aid healthcare professionals in the promotion and timing of interventions to support the child and family. The current manuscript reflects ongoing analyses of longitudinal data. No patient or public contribution to the analyses were required for testing the differential susceptibility theory. The authors would solicit patient or public contribution when implementing practice or policy changes based on the results.

Cardiovascular Morbidities in Adults Born Preterm: Getting to the Heart of the Matter!

Advances in perinatal and neonatal care have led to improved survival of preterm infants into adulthood. However, the shift in focus to long-term health in adults born preterm requires a clear understanding of the impact of prematurity on developing organ systems and the development of adult-oriented disease. A less well-recognized area of risk for surviving preterm infants is their cardiometabolic health. Epidemiologic evidence has linked preterm birth to the development of systemic hypertension, type 2 diabetes, metabolic syndrome, heart failure, and ischemic heart disease. Of more significant concern is that the risk of cardiometabolic disorders is higher in adults born preterm compared to full-term infants. The interconnected nature of the cardio-pulmonary system means worsening morbidity and mortality in adults born preterm. Addressing the problems of adults born preterm holistically would help promote cardiovascular health, wellness, and quality of life over their lifetime. Recognizing that adults born preterm are a unique subset of the population is a challenge in the current healthcare environment. Addressing issues relevant to adults born preterm in the clinically and research domain, using technology to characterize cardiopulmonary physiology and exercise tolerance, developing screening tools for early diagnosis and treatment, and robust follow-up of these infants with access to longitudinal data would improve both the quality and longevity of life in adults born preterm.

Differential Susceptibility: An Explanation for Variability in Life Course Health and Developmental Outcomes

Differential susceptibility theory posits that some individuals, with specific characteristics, are more, or less susceptible than others, to both adverse and beneficial environmental influences. It offers a perspective for understanding the directional trajectories across the life course affected by daily context and individual characteristics, in order to identify influential components. The aim of this article is to describe differential susceptibility theory, critically evaluate research findings in which the theory is tested, and consider implications of differential susceptibility theory as a theoretical framework for nursing science. Preterm birth trajectories and outcomes research are used as a lens for this examination.

Insulin resistance parameters in children born very preterm and adequate for gestational age

BACKGROUND

Preterm neonates are at risk for metabolic syndrome later in life. Whether prematurity constitutes an independent risk factor for the development of cardiovascular disease and metabolic syndrome remains controversial.

OBJECTIVE

To compare anthropometric measures, cardiometabolic risk factors and insulin resistance variables between children who were born very preterm (VPT, <32 gestational weeks) and at term (Term, >37 gestational weeks) and adequate for gestational age (AGA).

METHODS

We designed a cross-sectional cohort study, recruiting 120 children (5.0-8.5 years old) from the preterm clinic at Red de Salud UC-Christus and Complejo Asistencial Dr. Sótero del Río, and term children from the community. We excluded children born small for gestational age, based on INTERGROWTH21. Anthropometrics data were classified using WHO reference standards. The homeostasis model assessment insulin resistance (HOMA-IR) index, quantitative insulin sensitivity check index (QUICKI), triglyceride-to-HDL-C ratio (TG/HDL-C) and Pediatric Score Index for Metabolic Syndrome (PsiMS) were calculated.

RESULTS

VPT children born AGA had lower HDL cholesterol levels (p = .019) and a higher PsiMS score than those born at term (p = .043). We observed a higher percentage of children with HDL cholesterol ≤40 mg/dl (13.0% vs. 2.3%, p = .026) and BP ≥90th percentile among the VPT children than among the Term children (26.0% vs. 11.6%, p = .031).

CONCLUSIONS

At school age, blood pressure was higher, and HDL-C was lower among VPT children born AGA, suggesting a potential metabolic risk; therefore, it is essential to follow this group throughout their lives.

Mathematical performance in childhood and early adult outcomes after very preterm birth: an individual participant data meta-analysis

AIM

To investigate the strength of the independent associations of mathematics performance in children born very preterm (<32wks' gestation or <1500g birthweight) with attending postsecondary education and their current employment status in young adulthood.

METHOD

We harmonized data from six very preterm birth cohorts from five different countries and carried out one-stage individual participant data meta-analyses (n=954, 52% female) using mixed effects logistic regression models. Mathematics scores at 8 to 11 years of age were z-standardized using contemporary cohort-specific controls. Outcomes included any postsecondary education, and employment/education status in young adulthood. All models were adjusted for year of birth, gestational age, sex, maternal education, and IQ in childhood.

RESULTS

Higher mathematics performance in childhood was independently associated with having attended any postsecondary education (odds ratio [OR] per SD increase in mathematics z-score: 1.36 [95% confidence interval {CI}: 1.03, 1.79]) but not with current employment/education status (OR 1.14 per SD increase [95% CI: 0.87, 1.48]).

INTERPRETATION

Among populations born very preterm, childhood mathematics performance is important for adult educational attainment, but not for employment status.

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.

Lifetime cardiovascular risk factors and maternal and offspring birth outcomes: Bogalusa Babies

Both cardiovascular and reproductive complications may have origins in utero or in early life. Women in the Bogalusa Heart Study (n = 1401) had been linked to birth certificates for birthweight and gestational data, which were examined relative to childhood (ages 4–16) cardiometabolic indicators, indicated by mean levels overall and total risk factor burden as estimated by area under the curve (AUC) computed from longitudinal quadratic random-effects growth models. Women reported the birthweight and gestational age of each of their own pregnancies, and delivery medical records were linked to interview data where possible. Path analyses were conducted to examine the relationships among a woman’s own birth outcomes, childhood and preconception adult cardiovascular health, and birth outcomes. Mean blood pressure (systolic blood pressure (SBP) adjusted relative risk (aRR) per 1-SD increase, 1.27, 95% CI 1.04–1.57) and low-density lipoprotein (aRR 1.21, 95% CI 1.02–1.44) in childhood predicted preterm birth (PTB), while mean SBP (aRR 1.33, 95% CI 1.02–1.74) predicted term low birthweight. The AUC data suggested an association between blood pressure and PTB (aRR for SBP top 10%, 1.86, 95% CI 1.08–3.21). Pre-pregnancy total cholesterol was negatively associated with gestational age. In path analyses, positive associations were found for each step between own birthweight, childhood BMI, pre-pregnancy BMI, and child’s birthweight. Childhood levels of some, though not all, cardiovascular risk factors may predict adverse birth outcomes (preterm birth and reduced fetal growth).

Prematurity and the Risk of Development of Childhood Obesity: Piecing Together the Pathophysiological Puzzle. A Literature Review

One of the most devastating public health challenges in the twenty-first century is childhood obesity, and its prevalence is growing at a frightening rate. Premature infants have a greater likelihood of childhood obesity at age six to 16 compared to term infants. This study aims to explore the underlying mechanism of developing childhood obesity in this high-risk group. There are most likely multiple interconnected and supporting mechanisms that put this vulnerable population at risk of childhood obesity. Inflammation is a possible root cause. Prenatal causes included epigenetic changes as well as placental inflammation. Disturbances in hormonal pathways and elevated levels of serum bilirubin are possible explanations. Furthermore, preventable factors in the postnatal period were identified, such as weight gain and exclusive breastfeeding.

The prevalence of childhood obesity in preterm infants is high; thus, it is essential to understand the pathophysiology and address any preventable factors to decrease this disease burden.

Postnatal Expression Profile of MicroRNAs Associated with Cardiovascular Diseases in 3- to 11-Year-Old Preterm-Born Children

(1) Background: Preterm-born children have an increased cardiovascular risk with the first clinical manifestation during childhood and/or adolescence. (2) Methods: The occurrence of overweight/obesity, prehypertension/hypertension, valve problems or heart defects, and postnatal microRNA expression profiles were examined in preterm-born children at the age of 3 to 11 years descending from preterm prelabor rupture of membranes (PPROM) and spontaneous preterm birth (PTB) pregnancies. The whole peripheral blood gene expression of 29 selected microRNAs associated with cardiovascular diseases was the subject of our interest. (3) Results: Nearly one-third of preterm-born children (32.43%) had valve problems and/or heart defects. The occurrence of systolic and diastolic prehypertension/hypertension was also inconsiderable in a group of preterm-born children (27.03% and 18.92%). The vast majority of children descending from either PPROM (85.45%) or PTB pregnancies (85.71%) had also significantly altered microRNA expression profiles at 90.0% specificity. (4) Conclusions: Postnatal microRNA expression profiles were significantly influenced by antenatal and early postnatal factors (gestational age at delivery, birth weight of newborns, and condition of newborns at the moment of birth). These findings may contribute to the explanation of increased cardiovascular risk in preterm-born children. These findings strongly support the belief that preterm-born children should be dispensarized for a long time to have access to specialized medical care.

Premature birth, low birth weight, small for gestational age and chronic non-communicable diseases in adult life: A systematic review with meta-analysis

BACKGROUND

Individuals who were born prematurely (PT), with low birth weight (LBW), or small for gestational age (SGA) appear to present a set of permanent changes that make them more susceptible to develop chronic non-communicable diseases (CNCD) in adult life.

AIM

Investigating the association between PT birth, LBW or SGA at birth and CNCD incidence in adult life.

METHODS

Systematic review with meta-analysis of studies available in three databases - two of them are official (PubMed and Web of Science) and one is gray literature (OpenGrey) - based on pre-established search and eligibility criteria.

RESULTS

Sixty-four studies were included in the review, 93.7% of them only investigated one of the exposure variables (46.7% LBW, 35.0% PT and 18.3% SGA at birth), whereas 6.3% investigated more than one exposure variable (50.0% LBW and PT; 50.0% SGA and PT). There was association among all exposure variables in the following outcomes: cardiometabolic (CMD) and glycidic metabolism (GMD) disorders, changes in body composition and risk of developing metabolic syndrome (MS). Female sex was identified as risk factor in the exposure-outcome association. Eighteen (18) articles were included in the meta-analysis. There was positive association between LBW and incidence of CMD (OR: 1.25 [95%CI: 1.11; 1.41]; 07 studies), GMD (OR: 1.70 [95%CI: 1.25; 2.30]; 03 studies) and MS (OR: 1.75 [95%CI: 1.27; 2.40]; 02 studies) in adult life. PT was positively associated with CMD (OR: 1.38 [95%CI: 1.27; 1.51]; 05 studies).

CONCLUSIONS

LBW and PT are associated with CMD and GMD development, as well as with the risk of developing MS in adult life.

Late adolescent & young adult functioning and participation outcomes after prematurity

There has been an increased emphasis on optimizing health, developmental, and behavioral outcomes over the life course after prematurity. An important framework for examining adolescent and young adult outcomes is the International Classification of Functioning Disability and Health Children (ICF) developed by the World Health Organization (WHO) in 2001 and expanded to children and youth (ICF-CY) under age 19 years in 2007. The ICF and the ICF-CY can be used as a statistical tool in population studies, a research tool to measure outcomes, quality of life, and environmental factors, a clinical tool for outcomes of rehabilitation and vocation training, and as a social policy-educational tool to raise awareness and promote social action for equity. In this review we describe how functioning and participation can help inform transitional outcomes at age 17 years and emerging adult independence at 23 years. We highlight outcomes in adolescence and adulthood of former preterm infants using the ICF domains of functioning and participation. We include current standardized adaptive assessments (Vineland Adaptive Behavior Scales-3rd Edition; VABS3) and Adaptive Behavior Assessment Scale-3; ABAS3) that measure self-care daily living skills, applied learning, and social functioning. We also emphasize that participation involves life activities of higher education attainment, completing vocational training, experiencing employment, living independently, and relationship experiences with partners as well as family formation.

Novel method of measuring chronic stress for preterm infants: Skin cortisol

BACKGROUND AND OBJECTIVES

Infants who begin life in the medicalized environment of the neonatal intensive care unit (NICU) do so under stressful conditions. Environmental exposures are often abrasive to vulnerable infants, while invasive and noninvasive lifesaving interventions provide additional pain and/or stress. The most commonly selected biomarker to measure stress is cortisol. The skin is the barrier between the external environment and communicates with our neurological, endocrine and immune regulatory networks. To examine if skin cortisol may be a reliable biomarker of stress, NICU stress exposure and repeated measurements of skin cortisol in very preterm infants were examined retrospectively during the first 6 weeks of life. The temporal relationship between skin cortisol and NICU stress exposure was also analyzed.

MATERIALS AND METHODS

Participants included 82 preterm infants born weighing less than 1500 g, admitted to a level III NICU, with a mean gestational age of 28.5 weeks. Infants were studied from birth through 6 weeks of life. NICU stress data was collected using the Neonatal Infant Stressor Scale. Skin samples were collected using d-squame tape as soon after birth as possible and every two weeks thereafter.

RESULTS

On average, infants experienced approximately 43 stressful events per day during the first 6 weeks of life in the NICU. Stress level and cortisol reactivity varied by gestation age. Higher stress resulted in higher cortisol for infant >28 weeks; lower stress scores were associated with higher stress for infants <28 weeks. Stress exposure during 7 days prior to cortisol sampling yielded the highest AUC for the 2 groups. A statistically significant interaction was identified between gestational age and stress exposure during the previous 7 days (p < 0.01).

CONCLUSION

This is the first study to demonstrate skin cortisol as a preterm infant biomarker of chronic stress exposure. For infants with appropriate skin maturation, this non-invasive sampling method provides several benefits. Importantly, this method may be less intrusive and disruptive for preterm infants.