Is very preterm birth a risk factor for adult cardiometabolic disease?

Body Composition in Adults Born at Very Low Birthweight-A Sibling Study

BACKGROUND

Individuals born preterm at very low birthweight (VLBW, < 1500 g) tend to attain a smaller adult body size compared with term-born peers but less is known regarding specific body composition characteristics.

OBJECTIVES

We aimed to assess whether adults born at VLBW have less beneficial body composition characteristics, potentially mediating the association between VLBW birth and cardiometabolic disease. Sibling controls were used to account for the potential influence of shared genetic and/or lifestyle factors.

METHODS

This cohort study featured 77 adults born at VLBW and 70 term-born siblings. Dual-energy X-ray absorptiometry assessment took place at a mean age of 29 years. Fat mass (FM) distribution was calculated by dividing appendicular by truncal FM. Appendicular skeletal mass (ASM) measurements were used to calculate two indices: Skeletal mass index (SMI, ASM divided by height squared) and ASM/BMI (ASM divided by body mass index). Data were analysed by linear mixed models. An exploratory analysis subdivided the VLBW group by size at gestational age [small or appropriate for gestational age (SGA, defined as a birthweight < 2 SD, or AGA)].

RESULTS

Participants born at VLBW were lighter (-4.7 kg, 95% CI -8.2, -1.2) and shorter (-4.3 cm, 95% CI -6.2, -2.4) than sibling peers. After controlling for sex, age, and maternal factors, they had lower limb/trunk fat ratios (-0.06, 95% CI -0.11, -0.003), LBM (-2.02 kg, 95% CI -3.92, -0.12), ASM (-1.22 kg, 95% CI -2.14, -0.30) and ASM/BMI (-0.05, 95% CI -0.10, -0.004). FM and SMI did not differ between groups. In the subgroup analysis, findings were limited to those born VLBW + SGA.

CONCLUSIONS

Individuals born at VLBW had, on average, lower limb/trunk fat ratios and lower relative ASM compared with term-born siblings. A more centralised fat distribution, as well as lower appendicular muscle mass, could potentially mediate the association between VLBW birth and cardiometabolic risk.

Device-measured physical activity in adults born preterm with very low birth weight and mediation by motor abilities

Physical activity (PA) is beneficial for several health outcomes. Adults born with very low birth weight (VLBW<1500g) undertake less PA than those born at term, have poorer motor abilities and may serve as a model on early life origins of PA. We therefore examined whether motor abilities mediate the association between being born with VLBW and device-measured PA. In a joint assessment of two longitudinal birth cohorts from Finland and Norway, PA was measured by two tri-axial accelerometers in 87 adults born preterm with VLBW and 109 controls born at term. We explored the mediating role of motor abilities assessed by standardized tests on the association between VLBW and device-measured PA. To do this, we examined group differences in metabolic equivalent of task (MET) min/day of moderate to vigorous PA (MVPA), light PA and sedentary. Analyses were adjusted for cohort, age and sex. MVPA was 40.4 (95% confidence interval [CI]: 13.3 to 69.4) MET min/day lower in the VLBW group than the control group. This was in part mediated through gross motor abilities, indicated by the indirect effect on the association between VLBW and MVPA being -15.6 (95% CI: -28.5 to -5.4) MET min/day. In conclusion, adults born preterm with VLBW undertake less MVPA than controls born at term, and gross motor abilities mediate this association. Interventions targeting motor abilities should be examined as potential ways to increase PA.

Risk of Obesity and Unhealthy Central Adiposity in Adolescents Born Preterm With Very Low Birthweight Compared to Term-Born Peers

Background: Early-life factors such as preterm birth or very low birthweight (VLBW) are associated with increased cardiovascular disease risk. However, it remains unknown whether this is due to an increased risk of obesity (unhealthy central adiposity) because studies have predominantly defined obesity based on BMI, an imprecise adiposity measure. Objective: Investigate if adolescents born preterm with VLBW have a higher risk of unhealthy central adiposity compared to term-born peers. Study Design: Cross-sectional analysis of data from a prospective cohort study of 177 individuals born preterm with VLBW (<1500 g) and 51 term-born peers (birthweight ≥2500 g). Individuals with congenital anomalies, genetic syndromes, or major health conditions were excluded. Height, weight, waist circumference, skin fold thickness, and dual energy X-ray absorptiometry body composition were measured at age 14 years. We calculated BMI percentiles and defined overweight/obesity as BMI ≥85th percentile for age and sex. We estimated the preterm-term differences in overweight/obesity prevalence and adiposity distribution with multivariable generalized linear models. Results: There was no difference in small for gestational age status or overweight/obesity prevalence. Compared to term, youth born preterm with VLBW had lower BMI z-score [β -0.38, 95% confidence limits (CL) -0.75 to -0.02] but no differences in adiposity apart from subscapular-to-triceps ratio (STR; β 0.18, 95% CL 0.08 to 0.28). Conclusions: Adolescents born preterm with VLBW had smaller body size than their term-born peers and had no differences in central adiposity except greater STR.

Frontiers in the Etiology and Treatment of Preterm Premature Rupture of Membrane: From Molecular Mechanisms to Innovative Therapeutic Strategies

Preterm premature rupture of membranes (pPROM) poses a significant threat to fetal viability and increases the risk for newborn morbidities. The perinatal period of preterm infants affected by pPROM is often characterized by higher rates of mortality and morbidity, with associated risks of cerebral palsy, developmental delays, compromised immune function, respiratory diseases, and sensory impairments. pPROM is believed to result from a variety of causes, including but not limited to microbially induced infections, stretching of fetal membranes, oxidative stress, inflammatory responses, and age-related changes in the fetal-placental interface. Maternal stress, nutritional deficiencies, and medically induced procedures such as fetoscopy are also considered potential contributing factors to pPROM. This comprehensive review explores the potential etiologies leading to pPROM, delves into the intricate molecular mechanisms through which these etiologies cause membrane ruptures, and provides a concise overview of diagnostic and treatment approaches for pPROM. Based on available therapeutic options, this review proposes and explores the possibilities of utilizing a novel composite hydrogel composed of amniotic membrane particles for repairing ruptured fetal membranes, thereby holding promise for its clinical application.

Physical activity and cognitive function in adults born very preterm or with very low birth weight-an individual participant data meta-analysis

OBJECTIVE

Individuals born very preterm (<32 weeks of gestation) or with very low birthweight (<1500g) have lower cognitive function compared with term-born peers. Furthermore, some studies suggest that they are less physically active as young adults than controls, but the relationship between physical activity and cognitive function remains unclear. We performed an individual participant data meta-analysis to examine whether being born preterm/with very low birth weight is associated with physical activity in adulthood and examined if cognitive function mediates this association.

STUDY DESIGN

Cohorts with data on physical activity and cognitive function in adults born very preterm/very low birth weight and term-born controls were recruited from the Research on European Children and Adults Born Preterm, and the Adults Born Preterm International Collaboration Consortia. A systematic literature search was performed in PubMed and Embase.

RESULTS

Five cohorts with 1644 participants aged 22-28 years (595 very preterm/very low birth weight and 1049 controls) were included. Adults born very preterm/very low birth weight reported 1.11 (95% CI: 0.68 to 1.54) hours less moderate to vigorous physical activity per week than controls, adjusted for cohort, age and sex. The difference between individuals born very preterm/very low birth weight and controls was larger among women than among men. Neither intelligence quotient nor self-reported executive function mediated the association between very preterm/very low birth weight and moderate to vigorous physical activity. Results were essentially the same when we excluded individuals with neurosensory impairments.

CONCLUSION

Adults born very preterm/very low birth weight, especially women, reported less moderate to vigorous physical activity than their term-born peers. Cognitive function did not mediate this association. Considering the risk of adverse health outcomes among individuals born preterm, physical activity could be a target for intervention.

Maintaining an active lifestyle from adolescence to adulthood might alleviate the adverse association of preterm birth with cardiometabolic health

AIMS

We aimed to determine whether physical activity attenuates preterm birth's adverse effects on adult cardiometabolic health.

METHODS

This retrospective study utilized data from the Add Health Study, a prospective cohort conducted in the United States. During Wave V (mean age: 37 years; 60.7% women; mean body mass index: 29 kg/m2; mean waist circumference: 95 cm), we evaluated cardiometabolic risk factors and preterm birth status (i.e., born <37 weeks). Self-reported physical activity data was collected through questionnaires during Waves I (ages 12-19) and Wave V. An "active lifestyle" was defined by adherence to recommendations during both waves, spanning from adolescence to adulthood.

RESULTS

The sample, comprising 3320 individuals, with 9.5% being preterm, included 7.6% who remained physically active throughout both adolescence and adulthood. Preterm-born individuals who were inactive had higher rates of obesity (incidence rate ratio [IRR] = 1.39, 95% confidence interval (CI) 1.05-1.84), abdominal obesity (IRR = 1.46, 95% CI 1.11-1.92), hyperlipidemia (IRR 3.50, 95% CI 1.94-4.29), type 2 diabetes (IRR = 2.37, 95% CI 1.12-5.01), and metabolic syndrome (IRR = 2.61, 95% CI 1.17-5.80) compared to active term-born individuals. Maintaining an active lifestyle appeared to decrease the risk of obesity and hyperlipidemia in adults born preterm (p > 0.05).

CONCLUSIONS

While preterm birth is associated with an elevated risk of adult cardiometabolic risk, maintaining an active lifestyle appeared to slightly mitigate the risk of obesity and hyperlipidemia in adults born preterm.

Preterm birth and exercise capacity: what do we currently know?

Objectives

The long-term cardiopulmonary outcomes following preterm birth during the surfactant era remain unclear. Respiratory symptoms, particularly exertional symptoms, are common in preterm children. Therefore, cardiopulmonary exercise testing may provide insights into the pathophysiology driving exertional respiratory symptoms in those born preterm. This review aims to outline the current knowledge of cardiopulmonary exercise testing in the assessment of children born preterm in the surfactant era.

Design

This study is a narrative literature review.

Methods

Published manuscripts concerning the assessment of pulmonary outcomes using cardiopulmonary exercise testing in preterm children (aged <18 years) were reviewed. Search terms related to preterm birth, bronchopulmonary dysplasia, and exercise were entered into electronic databases, including Medline, PubMed, and Google Scholar. Reference lists from included studies were scanned for additional manuscripts.

Results

Preterm children have disrupted lung development with significant structural and functional lung disease and increased respiratory symptoms. The association between these (resting) assessments of respiratory health and exercise capacity is unclear; however, expiratory flow limitation and an altered ventilatory response (rapid, shallow breathing) are seen during exercise. Due to the heterogeneity of participants, treatments, and exercise protocols, the effect of the aforementioned limitations on exercise capacity in children born preterm is conflicting and poorly understood.

Conclusion

Risk factors for reduced exercise capacity in those born preterm remain poorly understood; however, utilizing cardiopulmonary exercise testing to its full potential, the pathophysiology of exercise limitation in survivors of preterm birth will enhance our understanding of the role exercise may play. The role of exercise interventions in mitigating the risk of chronic disease and premature death following preterm birth has yet to be fully realized and should be a focus of future robust randomized controlled trials.

Gestational age and trajectories of body mass index and height from birth through adolescence in the Danish National Birth Cohort

Preterm birth is associated with smaller body dimensions at birth. The impact on body size in later life, measured by body mass index (BMI) and height, remains unclear. A prospective register-based cohort study with 62,625 singletons from the Danish National Birth Cohort born 1996-2003 for whom information on gestational age (GA) at birth, length or weight at birth, and at least two growth measurements scheduled at the ages of 5 and 12 months, and 7, 11 and 18 years were available. Linear mixed effects with splines, stratified by sex, and adjusted for confounders were used to estimate standardised BMI and height. GA was positively associated with BMI in infancy, but differences between preterm and term children declined with age. By age 7, preterm children had slightly lower BMI than term children, whereas no difference was observed by adolescence (mean difference in BMI z-score - 0.28 to 0.15). GA was strongly associated with height in infancy, but mean differences between individuals born preterm and term declined during childhood. By adolescence, the most preterm individuals remained shorter than their term peers (mean difference in height z-score from - 1.00 to - 0.28). The lower BMI in preterm infants relative to term infants equalizes during childhood, such that by adolescence there is no clear difference. Height is strongly positively associated with GA in early childhood, whilst by end of adolescence individuals born preterm remain slightly shorter than term peers.

Role of Transcription Factors in the Management of Preterm Birth: Impact on Future Treatment Strategies

Preterm birth is defined as the birth of a neonate before 37 weeks of gestation and is considered as a leading cause of the under five deaths of neonates. Neonates born preterm are known to have higher perinatal mortality and morbidity with associated risks of low birth weight, respiratory distress syndrome, gastrointestinal, immunologic, central nervous system, hearing, and vision problems, cerebral palsy, and delayed development. India leads the list of countries with the greatest number of preterm births. The studies focusing on the molecular mechanisms related to the etiology of preterm birth have described the role of different transcription factors. With respect to this, transcription factors like peroxisome proliferator activated receptors (PPAR), nuclear factor kappa β (NF-kβ), nuclear erythroid 2-related factor 2 (Nrf2), and progesterone receptor (PR) are known to be associated with preterm labor. All these transcription factors are linked together with a common cascade involving inflammatory processes. Thus, the current review describes the possible cross-talk between these transcription factors and their therapeutic potential to prevent or manage preterm labor.

Cardiac cycle: an observational/interventional study protocol to characterise cardiopulmonary function and evaluate a home-based cycling program in children and adolescents born extremely preterm

INTRODUCTION

Extremely preterm (EP)/extremely low birthweight (ELBW) individuals may have an increased risk for adverse cardiovascular outcomes. Compared with term-born controls, these individuals have poorer lung function and reduced exercise capacity. Exercise interventions play an important role in reducing cardiopulmonary risk, however their use in EP/ELBW cohorts is unknown. This study, cardiac cycle, aims to characterise the cardiopulmonary system of children and adolescents who were born EP compared with those born at term, following acute and chronic exercise bouts.

METHODS AND ANALYSIS

The single-centre study comprises a home-based exercise intervention, with physiological characterisation at baseline and after completion of the intervention. Fifty-eight children and adolescents aged 10-18 years who were born EP and/or with ELBW will be recruited. Cardiopulmonary function assessed via measures of blood pressure, arterial stiffness, capillary density, peak oxygen consumption, lung clearance indexes and ventricular structure/function, will be compared with 58 age-matched and sex-matched term-born controls at baseline and post intervention. The intervention will consist of a 10-week stationary cycling programme, utilising Zwift technology.

ETHICS AND DISSEMINATION

The study is approved by the Ethics Committee of the Royal Children's Hospital Melbourne under HREC2019.053. Results will be disseminated via peer-reviewed journal regardless of outcome.

TRIAL REGISTRATION NUMBER

12619000539134, ANZCTR.

Effect of moderate to high intensity aerobic exercise on blood pressure in young adults: The TEPHRA open, two-arm, parallel superiority randomized clinical trial

Background

Exercise is advised for young adults with elevated blood pressure, but no trials have investigated efficacy at this age. We aimed to determine whether aerobic exercise, self-monitoring and motivational coaching lowers blood pressure in this group.

Methods

The study was a single-centre, open, two-arm, parallel superiority randomized clinical trial with open community-based recruitment of physically-inactive 18-35 year old adults with awake 24 h blood pressure 115/75mmHg-159/99 mmHg and BMI<35 kg/m2. The study took place in the Cardiovascular Clinical Research Facility, John Radcliffe Hospital, Oxford, UK. Participants were randomized (1:1) with minimisation factors sex, age (<24, 24-29, 30-35 years) and gestational age at birth (<32, 32-37, >37 weeks) to the intervention group, who received 16-weeks aerobic exercise training (three aerobic training sessions per week of 60 min per session at 60-80% peak heart rate, physical activity self-monitoring with encouragement to do 10,000 steps per day and motivational coaching to maintain physical activity upon completion of the intervention. The control group were sign-posted to educational materials on hypertension and recommended lifestyle behaviours. Investigators performing statistical analyses were blinded to group allocation. The primary outcome was 24 h awake ambulatory blood pressure (systolic and diastolic) change from baseline to 16-weeks on an intention-to-treat basis. Clinicaltrials.gov registered on March 30, 2016 (NCT02723552).

Findings

Enrolment occurred between 30/06/2016-26/10/2018. Amongst the 203 randomized young adults (n = 102 in the intervention group; n = 101 in the control group), 178 (88%; n = 76 intervention group, n = 84 control group) completed 16-week follow-up and 160 (79%; n = 68 intervention group, n = 69 control group) completed 52-weeks follow-up. There were no group differences in awake systolic (0·0 mmHg [95%CI, -2·9 to 2·8]; P = 0·98) or awake diastolic ambulatory blood pressure (0·6 mmHg [95%CI, -1·4. to 2·6]; P = 0·58). Aerobic training increased peak oxygen uptake (2·8 ml/kg/min [95%CI, 1·6 to 4·0]) and peak wattage (14·2watts [95%CI, 7·6 to 20·9]) at 16-weeks. There were no intervention effects at 52-weeks follow-up.

Intepretation

These results do not support the exclusive use of moderate to high intensity aerobic exercise training for blood pressure control in young adults.

Funding

Wellcome Trust, British Heart Foundation, National Institute for Health Research, Oxford Biomedical Research Centre.

Social-Emotional Functioning and Dietary Intake among Children Born with a Very Low Birth Weight

Very low birth weight infants (VLBW, <1500g) are at elevated risk of neurodevelopmental disorders, later obesity and cardiometabolic disease; if and how neurodevelopmental disorders impact chronic disease risk is poorly understood. The most common neurodevelopmental disorders experienced by VLBW children are those of social-emotional functioning. We compared dietary patterns and body composition between VLBW children with poor vs. typical social-emotional functioning using linear mixed models adjusted for sex, gestational age, cognitive impairment, parental education and BMI. VLBW children (n=158) attending the Donor Milk for Improved Neurodevelopmental Outcomes trial 5.5-year follow-up participated. Poor social-emotional functioning was based on standardized parent-rated questionnaires and/or parent-reported physician diagnosis of autism spectrum or attention-deficit/hyperactivity disorders. Most children had diets categorized as 'needs improvement' (67%) or 'poor' (27%) and 29% of children exhibited poor social-emotional functioning. Poor social-emotional functioning was positively associated with 100% fruit juice (β=0.3 cup equivalents/day; 95% CI 0.1, 0.5) and energy intake (β=118.1 kcals/day; 95% CI 0.9, 235.2). Children with poor social-emotional functioning were more likely to have a limited food repertoire (p=0.02), but less likely to exceed dietary fat recommendations (p=0.04). No differences in overall diet quality or body composition were observed. Diet counselling and research are essential to improving the nutrition of VLBW children to mitigate chronic disease risk. Novelty: • Overall diet quality and body composition did not differ between VLBW children with poor vs. typical social-emotional functioning. • Most had diets "needing improvement" or "poor" according to the HEI 2010. • Diet counselling may help mitigate chronic disease risk in this vulnerable population.

Obstetric outcomes in pregnancies resulting from in vitro fertilization are not different in fertile, sterilized women compared to infertile women: A Society for Assisted Reproductive Technology database analysis

OBJECTIVE

To compare obstetric and neonatal outcomes resulting from assisted reproductive technology in couples with a history of female sterilization to couples with other infertility diagnoses.

DESIGN

Retrospective cohort study.

SETTING

Not applicable.

PATIENT(S)

Fresh, nondonor cycles excluding gestational surrogacy from 2004 to 2013 in the United States.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Preterm birth rates and low birth weight rates from in vitro fertilization (IVF) pregnancies in couples with infertility and in couples with prior tubal ligation as their sole indication for IVF.

RESULT(S)

The mean ages of fertile women (N = 8,478) and infertile women (N = 371,488) were 35.3 and 34.6 years, respectively. Of the singletons born to parous women (N = 26,463), the incidence of preterm birth was not significantly different in fertile, sterilized couples compared to infertile couples (13.7% vs. 12.0%). The incidence of low birth weight among term singletons was also not significantly different between fertile couples compared to infertile couples (3.5% vs. 3.2%).

CONCLUSION(S)

Fertile couples have similar preterm birth and low birth weight rates after IVF compared to infertile couples. This suggests that differences in perinatal outcomes may be due to assisted reproductive technology procedures rather than infertility itself.

Common Core Assessments in follow-up studies of adults born preterm-Recommendation of the Adults Born Preterm International Collaboration

BACKGROUND

Of all newborns, 1%-2% are born very preterm (VP; <32 weeks) or with very low birthweight (VLBW; ≤1500 g). Advances in prenatal and neonatal care have substantially improved their survival, and the first generations who have benefited from these advances are now entering middle age. While most lead healthy lives, on average these adults are characterised by a number of adversities. These include cardiometabolic risk factors, airway obstruction, less physical activity, poorer visual function, lower cognitive performance, and a behavioural phenotype that includes inattention and internalising and socially withdrawn behaviour that may affect life chances and quality of life. Outcomes in later adulthood are largely unknown, and identifying trajectories of risk or resilience is essential in developing targeted interventions. Joint analyses of data and maintenance of follow-up of cohorts entering adulthood are essential. Such analyses are ongoing within the Adults Born Preterm International Collaboration (APIC; www.apic-preterm.org). Joint analyses require data harmonisation, highlighting the importance of consistent assessment methodologies.

OBJECTIVE

To present an expert recommendation on Common Core Assessments to be used in follow-up assessments of adults born preterm.

METHODS

Principles of Common Core Assessments were discussed at APIC meetings. Experts for each specific outcome domain wrote the first draft on assessments pertaining to that outcome. These drafts were combined and reviewed by all authors. Consensus was reached by discussion at APIC meetings.

RESULTS

We present a recommendation by APIC experts on consistent measures to be used in adult follow-up assessments.

CONCLUSIONS

The recommendation encompasses both "core" measures which we recommend to use in all assessments of adults born preterm that include the particular outcome. This will allow comparability between time and location. The recommendation also lists optional measures, focusing on current gaps in knowledge. It includes sections on study design, cardiometabolic and related biomarkers, biological samples, life style, respiratory, ophthalmic, cognitive, mental health, personality, quality of life, sociodemographics, social relationships, and reproduction.

Mortality Among Young Adults Born Preterm and Early Term in 4 Nordic Nations

IMPORTANCE

Adverse long-term outcomes in individuals born before full gestation are not confined to individuals born at extreme gestational ages. Little is known regarding mortality patterns among individuals born in the weeks close to ideal gestation, and the exact causes are not well understood; both of these are crucial for public health, with the potential for modification of risk.

OBJECTIVE

To examine the risk of all-cause and noncommunicable diseases (NCD) deaths among young adults born preterm and early term.

DESIGN, SETTING, AND PARTICIPANTS

This multinational population-based cohort study used nationwide birth cohorts from Norway, Sweden, Denmark, and Finland for individuals born between 1967 and 2002. Individuals identified at birth who had not died or emigrated were followed up for mortality from age 15 years to 2017. Analyses were performed from June 2019 to May 2020.

EXPOSURES

Categories of gestational age (ie, moderate preterm birth and earlier [23-33 weeks], late preterm [34-36 weeks], early term [37-38 weeks], full term [39-41 weeks] and post term [42-44 weeks]).

MAIN OUTCOMES AND MEASURES

All-cause mortality and cause-specific mortality from NCD, defined as cancer, diabetes, chronic lung disease, and cardiovascular disease (CVD).

RESULTS

A total of 6 263 286 individuals were followed up for mortality from age 15 years. Overall, 339 403 (5.4%) were born preterm, and 3 049 100 (48.7%) were women. Compared with full-term birth, the adjusted hazard ratios (aHRs) for all-cause mortality were 1.44 (95% CI, 1.34-1.55) for moderate preterm birth and earlier; 1.23 (95% CI, 1.18-1.29) for late preterm birth; and 1.12 (95% CI, 1.09-1.15) for early-term birth. The association between gestational age and all-cause mortality were stronger in women than in men (P for interaction = .03). Preterm birth was associated with 2-fold increased risks of death from CVD (aHR, 1.89; 95% CI, 1.45-2.47), diabetes (aHR, 1.98; 95% CI, 1.44-2.73), and chronic lung disease (aHR, 2.28; 95% CI, 1.36-3.82). The main associations were replicated across countries and could not be explained by familial or individual confounding factors.

CONCLUSIONS AND RELEVANCE

The findings of this study strengthen the evidence of increased risk of death from NCDs in young adults born preterm. Importantly, the increased death risk was found across gestational ages up to the ideal term date and includes the much larger group with early-term birth. Excess mortality associated with shorter gestational age was most pronounced for CVDs, chronic lung disease, and diabetes.

Associations between Diet Quality and Body Composition in Young Children Born with Very Low Body Weight

BACKGROUND

Very low birth weight (VLBW; <1500 g) infants have increased adiposity and metabolic disease risk in adulthood. Limited evidence suggests low-quality childhood diets are a predisposing risk factor. Despite this, to our knowledge no study has yet examined associations between diet quality and body composition in VLBW individuals.

OBJECTIVE

The objective of this study was to determine associations between Healthy Eating Index-2010 (HEI-2010) scores and consumption of fruits/vegetables, added sugars, and macronutrients with body composition in 5.5-y-old children born VLBW. We hypothesized HEI-2010 scores were inversely associated with adiposity.

METHODS

This cohort study leveraged the 5.5-y follow-up to the Donor Milk for Improved Neurodevelopmental Outcomes randomized controlled trial. From June 2016 to July 2018, participants attended a follow-up visit at The Hospital for Sick Children, Canada, or were visited in their home. All 316 surviving infants from the trial were eligible, and the caregivers of 158 children (50%; 53% male) consented to follow-up. Diet quality (HEI-2010) and usual intake of fruits/vegetables, added sugars, and macronutrients were determined from two 24-h dietary recalls (ASA24). Linear regressions evaluated associations of diet with BMI (kg/m2) and waist circumference z-scores, total fat, fat-free mass (air displacement plethysmography), and skinfolds.

RESULTS

Mean ± SD age at follow-up was 5.7 ± 0.2 y, birth weight was 1013 ± 264 g, and gestational age was 27.9 ± 2.5 wk. Dietary data and BMI z-scores were available for all children; 123 completed air displacement plethysmography. HEI-2010 score was 58.2 ± 12.4 out of 100, and 27% of children had poor quality diets (scores ≤50). HEI-2010 scores were inversely associated with BMI z-score, but only in children with obese mothers. A 10-point increase in HEI-2010 score was associated with reduced BMI (β: -0.5 SD; 95% CI: -0.7, -0.2) and subscapular (-0.3 SD; 95% CI: -0.6, -0.06) z-scores.

CONCLUSIONS

Improving diet quality in children born VLBW with obese mothers may be an important strategy to prevent excess adiposity. This trial was registered at clinicaltrials.gov as Optimizing Mothers' Milk for Preterm Infants (OptiMoM) Program of Research: Study 1-Impact of Donor Milk at Kindergarten, NCT02759809.

Cardiovascular Health Profile at Age 25 Years in Adults Born Extremely Preterm or Extremely Low Birthweight

Being born extremely preterm (EP; <28 weeks' gestation) or extremely low birthweight (ELBW; <1000 g birthweight) may predict increased cardiometabolic risk in adulthood, but other early life predictors are less well described. We aimed to (1) compare cardiovascular health profiles between 165 adults born EP/ELBW and 127 controls at age 25 years, drawn from a prospective longitudinal cohort study, recruited at birth in 1991 to 1992; and (2) in the EP/ELBW group, determine early life associations of cardiovascular health. Cardiovascular health profiles were calculated individually for measures of anthropometry, abdominal visceral fat, blood pressure, fasting plasma glucose, insulin, lipids, C-reactive protein, vascular indices, exercise tolerance and smoking status, and summed for an overall score. Cardiovascular health profiles were compared between groups; using logistic regression (individual scores) and the Mann-Whitney U test (cumulative score). Compared with controls, adults born EP/ELBW had less favorable cardiovascular health profiles; individually for abdominal visceral fat (odds ratio, 0.56 [95% CI, 0.33-0.96], P=0.03), blood pressure (odds ratio 0.38 [95% CI, 0.23-0.63], P<0.001), exercise capacity (odds ratio 0.37 [95% CI, 0.22-0.63], P<0.001), and fasting glucose (odds ratio 0.51 [95% CI, 0.31-0.84], P=0.01) and overall (median [interquartile range] 10 [7-11] versus 11 [9-12], P=0.007). Male sex predicted unfavorable abdominal visceral fat, blood pressure and fasting glucose, and favorable exercise capacity. Greater increases in weight Z scores between 2 and 8, and 8 and 18 years predicted less favorable profiles of exercise capacity and visceral fat. Longer-term follow-up is critical to determine the cardiovascular sequelae of adults born EP/ELBW.

Cardiovascular risk factors in those born preterm - systematic review and meta-analysis

Emerging evidence demonstrates a link between preterm birth (PTB) and later life cardiovascular disease (CVD). We conducted a systematic review and meta-analysis to compare conventional CVD risk factors between those born preterm and at term. PubMed, CINAHL, SCOPUS, and EMBASE databases were searched. The review protocol is registered in PROSPERO (CRD42018095005). CVD risk factors including systolic blood pressure (SBP), diastolic blood pressure (DBP), body mass index, lipid profile, blood glucose, and fasting insulin among those born preterm (<37 weeks' gestation) were compared with those born at term (≥37 weeks' gestation). Subgroup analyses based on gender, age, gestational at birth (<32 weeks' gestation and <28 weeks' gestation), and PTB associated with small for gestational age or average for gestational age were also performed. Fifty-six studies provided data on 308,987 individuals. Being born preterm was associated with 3.26 mmHg (95% confidence interval [CI] 2.08 to 4.44) higher mean SBP and 1.32 mmHg (95% CI: 0.61 to 2.04) higher mean DBP compared to being born at term. Subgroup analyses demonstrated that SBP was higher among (a) preterm compared to term groups from early adolescence until adulthood; (b) females born preterm but not among males born preterm compared to term controls; and (c) those born at <32 weeks or <28 weeks compared to term. Our meta-analyses demonstrate higher SBP and DBP among those born preterm compared to term. The difference in SBP is evident from early adolescence until adulthood.

Exercise capacity in children with bronchopulmonary dysplasia at school age

OBJECTIVE

To assess the exercise capacity, exercise habits, and lung function of preterm born children with bronchopulmonary dysplasia (BPD) compared to term born controls at school age.

METHODS

Cardiopulmonary exercise test (CPET) by cycle ergometer and pulmonary function test were performed in children with BPD (n = 42) and compared with a term born control group (n = 42). Daily activity, participation in sports and respiratory symptoms were assessed by questionnaire.

RESULTS

Children with BPD versus controls had significantly lower values for oxygen consumption (V̇O₂ [mL/min] 1442 ± 417 vs. 1766 ± 541), minute ventilation (VE [L/min] 48 ± 14.92 vs. 60 ± 18.33), and workload (W [watt] 96.1 ± 16.7 vs. 110.6 ± 17.2) at peak exercise and a lower anaerobic threshold (VO₂ AT [mL/min] 1183 ± 345 vs. 1382 ± 398). When corrected for weight, only for the workload (2.7 ± 0.5 vs. 3.1 ± 0.5, p = 0.0013) did significant differences persist. The forced expiratory volume in 1 s and forced expiratory flow between 25 and 75% of expired forced vital capacity were significantly reduced in the BPD group (p < 0.0001). Children with BPD have a higher risk of reporting difficulties in physical activity (OR 2.5) and of suffering from wheezing or shortness of breath while exercising (OR 2.5).

CONCLUSION

Compared to term born controls, children with BPD at school age show airflow obstruction, a lower workload in CPET, and more respiratory symptoms related to physical activity. The comparable oxygen consumption based on weight suggests a functionally normal alveolar compartment.

Apolipoprotein Profiles in Very Preterm and Term-Born Preschool Children

Background

Little is known about plasma apolipoprotein profiles in very preterm‐born and term‐born preschool children compared with the adult population. This is of particular interest because apolipoprotein composition might contribute to cardiometabolic outcome in later life.

Methods and Results

Children aged 5 to 7 years born at term or with <32 weeks of gestation were included. Apolipoprotein concentrations were measured in plasma collected after an overnight fast using multiple‐reaction monitoring‐based mass spectrometry. Twelve apolipoproteins were measured in 26 former term and 38 former very preterm infants. Key findings were confirmed by assessing apolipoprotein levels using antibody‐based assays. Comparing children born term and preterm, apolipoprotein A‐I, A‐IV, C‐II, and C‐III were significantly higher in the latter group. Term‐born children showed plasma levels of apolipoprotein C‐II and C‐III quantitatively similar to the adult range (Bruneck study). Hierarchical clustering analyses suggested that a higher proportion of apolipoprotein C‐III and C‐II reside on high‐density lipoprotein particles in children than in adults given the marked correlations of apolipoprotein C‐III and C‐II with high‐density lipoprotein cholesterol and apolipoprotein A‐I in children but not adults. High‐density lipoprotein cholesterol concentrations were similar in children and adults but the pattern of high‐density lipoprotein cholesterol–associated apolipoproteins was different (lower apolipoprotein A‐I and C‐I but higher A‐II, A‐IV, and M).

Conclusions

Our study defines apolipoprotein profiles in preschoolers and reports potential effects of prematurity. Further large‐scale studies are required to provide evidence whether this apolipoprotein signature of prematurity, including high apolipoprotein C‐II and C‐III levels, might translate into adverse cardiometabolic outcome in later life.

Antenatal Steroid Exposure, Aerobic Fitness, and Physical Activity in Adolescents Born Preterm with Very Low Birth Weight

OBJECTIVE

To determine whether antenatal corticosteroid exposure is associated with aerobic fitness or physical activity participation in adolescents born preterm with very low birth weight (VLBW).

STUDY DESIGN

Observational cohort study of 14-year-old adolescents (n = 173) born with VLBW between 1992 and 1996 at a regional perinatal center with 91 exposed to antenatal corticosteroids. Aerobic fitness was determined from peak oxygen uptake (V˙O2peak) obtained via maximal exercise testing on a cycle ergometer. Physical activity levels for the past year and past 2 months were estimated from a questionnaire. Between-group comparisons for continuous variables were evaluated using independent t tests or Mann-Whitney U tests. Generalized linear models were used to compare differences in fitness and physical activity between those exposed to antenatal corticosteroids and not exposed to antenatal corticosteroids, with race and sex in models.

RESULTS

Regression analysis revealed an antenatal corticosteroids × sex × race interaction for V˙O2peak (P ≤ .001). Nonblack male adolescents exposed to antenatal corticosteroids had significantly greater V˙O2peak than nonblack male adolescents not exposed to antenatal corticosteroids expressed relative to body mass (mean difference [95% CI]; 8.5 [2.1-15.0] mL·kg-1·min-1) and lean body mass (9.0 [1.1-16.9] mL·kglean body mass-1·min-1). No antenatal corticosteroid group differences in V˙O2peak were evident in black male adolescents, or black and nonblack female adolescents. Male adolescents exposed to antenatal corticosteroids reported participating in significantly more total physical activity (medians: 14.6 vs 8.5) and vigorous physical activity (3.0 vs 0.95) per week for the past 2 months than male adolescents not exposed to antenatal corticosteroids.

CONCLUSIONS

Exposure to antenatal corticosteroids was associated with greater physical activity participation and aerobic fitness in adolescents with VLBW, particularly in nonblack male adolescents, which may confer health benefits in this at-risk population.

Postexercise Heart Rate Recovery in Adults Born Preterm

OBJECTIVE

To evaluate postexercise heart rate recovery (HRR) in adults born preterm.

STUDY DESIGN

We studied the association between preterm birth and postexercise HRR in 545 adults (267 women) at 23.3 years of age (range 19.9-26.3 years). One hundred three participants were born early preterm (<34 completed weeks), 178 late preterm (34-36), and 264 were full term (control group). HRR was calculated as change in heart rate (HR) 30 seconds and 60 seconds after cessation of submaximal step test and maximum HR slope during the first minute after.

RESULTS

Mean peak HR was 159.5 bpm in the early preterm (P = .16 with controls), 157.8 bpm in the late preterm (P = .56), and 157.0 bpm in the control group. Mean HRR 30 seconds after exercise was 3.2 bpm (95% CI 1.1-5.2) lower in the early preterm group and 2.1 bpm (0.3-3.8) lower in the late preterm group than the full term controls. Mean 60s HRR was 2.5 (-0.1 to 5.1) lower in the early preterm group and 2.8 bpm (0.6-4.9) lower in the late preterm group. Mean maximum slope after exercise was 0.10 beats/s (0.02-0.17) lower in the early preterm group and 0.06 beats/s (0.00-0.12) lower in the late preterm group.

CONCLUSIONS

Our results suggest reduced HRR after exercise in adults born preterm, including those born late preterm. This suggests altered reactivation of the parasympathetic nervous system, which may contribute to cardiovascular risk among adults born preterm.

Association of Preterm Birth With Risk of Ischemic Heart Disease in Adulthood

IMPORTANCE

Preterm birth has previously been associated with increased risks of hypertension and diabetes, but not ischemic heart disease (IHD), in adulthood. The reasons for this lack of association with IHD despite associations with its risk factors have been elusive, but may be associated with methodologic issues, such as survivor bias, in prior studies.

OBJECTIVE

To determine whether preterm birth is associated with an increased risk of IHD in adulthood in a large population-based cohort.

DESIGN, SETTING, AND PARTICIPANTS

This national, population-based cohort study included all 2 141 709 persons who were born as singleton live births in Sweden during 1973 to 1994. The data were analyzed in September 2018.

EXPOSURES

Gestational age at birth, identified from nationwide birth records in the Swedish Birth Registry.

MAIN OUTCOMES AND MEASURES

Ischemic heart disease that was identified from nationwide inpatient and outpatient diagnoses through 2015 (maximum age, 43 years). A Cox regression was used to examine gestational age at birth in association with IHD in adulthood while adjusting for other perinatal and maternal factors. Cosibling analyses assessed for potential confounding by unmeasured shared familial factors.

RESULTS

Of 2 141 709 participants, 1 041 906 (48.6%) were female and there were 1921 persons (0.09%) who received a diagnosis of IHD in 30.9 million person-years of follow-up. Gestational age at birth was inversely associated with IHD risk in adulthood. At ages 30 to 43 years, adjusted hazard ratios for IHD associated with preterm (gestational age <37 weeks) and early-term birth (37-38 weeks) were 1.53 (95% CI, 1.20-1.94) and 1.19 (1.01-1.40), respectively, compared with full-term birth (39-41 weeks). Preterm-born women had lower IHD incidence than preterm-born men (15.16 vs 22.00 per 100 000 person-years) but had a higher adjusted hazard ratio (1.93; 95% CI, 1.28-2.90 vs 1.37; 95% CI, 1.01-1.84). These associations did not appear to be explained by shared genetic or environmental factors in families.

CONCLUSIONS AND RELEVANCE

In this large national cohort, preterm and early-term birth were associated with an increased IHD risk in adulthood. Persons born prematurely need early evaluation and preventive actions to reduce the risk of IHD.

Association of physical activity and cardiorespiratory function or BMI and body composition in preterm-born individuals: a systematic review

AIM

To evaluate the association of physical activity (PA) and forced expiratory volume in one second (FEV1), peak oxygen consumption (pVO2), body mass index (BMI) and body composition in preterm-born individuals.

METHODS

Cochrane Library, EMBASE, MEDLINE, AMED, ERIC, Web of Science and PsycInfo were searched with no restriction on language and date of publication from inception to January 2018. Data were extracted comparing preterm-born individuals with different frequencies of PA and the outcome of interest.

RESULTS

One randomized controlled, two longitudinal and thirteen cross-sectional studies comprising 1922 preterm-born individuals aged 5-25 were included. Assessment varied from a PA program to accelerometer data, interviews and self-report questionnaires. In preterm-born children, more PA was associated with better cardiorespiratory function in those groups with impaired lung function or with lower BMI in those groups with increased risk factors, but no association was found in unimpaired children. In preterm-born adults, more PA was associated with higher pVO2 and lower BMI.

CONCLUSION

Only tentative conclusions can be drawn, especially regarding differences of the association of PA between preterm- and term-born populations. Further studies are needed to analyse the association of PA in preterm-born individuals with reduced cardiorespiratory function.

Cardiac Autonomic Function in Adults Born Preterm

OBJECTIVE

To evaluate cardiac autonomic function in adults born preterm.

STUDY DESIGN

We studied the association between prematurity and cardiac autonomic function using heart rate variability measurements in 600 adults (mean age of 23.3 years) from a geographically based cohort in Northern Finland. There were 117 young adults born early preterm (<34 weeks), 207 born late preterm (34-36 weeks), and 276 born at term (≥37 weeks, controls). Autonomic function was analyzed by calculating time and frequency domain heart rate variability measurements using linear regression.

RESULTS

Compared with controls, the mean difference in root mean square of successive differences (indicating cardiac vagal activity) was -12.0% (95% CI -22.2%, -0.5%, adjusted for sex, age, source cohort, and season P = .04) for the early preterm group and -7.8% (-16.8%, 2.0%, P = .12) for the late preterm group. Mean differences with controls in low frequency power (indicating cardiac vagal activity, including some sympathetic- and baroreflex-mediated effects) were -13.6% (-26.7%, 1.8%, P = .08) for the early preterm group and -16.4% (-27.0%, -4.3%, P = .01) for the late preterm group. Mean differences in high frequency power (quantifying cardiac vagal modulation in respiratory frequency) were -19.2% (-36.6%, 2.9%, P = .09) for the early preterm group and -13.8% (-29.4%, 5.3%, P = .15) for the late preterm group. Differences were attenuated when controlled for body mass index and physical activity.

CONCLUSIONS

Our results suggest altered autonomic regulatory control in adults born preterm, including those born late preterm. Altered autonomic regulatory control may contribute to increased cardiovascular risk in adults born preterm.

Women born with very low birth weight have similar menstrual cycle pattern, pregnancy rates and hormone profiles compared with women born at term

BACKGROUND

Individuals born very preterm or with very low birth weight (VLBW) have a reduced likelihood to reproduce according to population-based register studies. Extremely low-birth weight born adults had a lower reproduction rate for both men and women in a follow-up study.

AIM

To investigate if being born with VLBW is associated with differences in the reproductive health, i.e. age of menarche, menstrual cycle pattern, pregnancy rates and hormone profile compared with women born at term.

METHODS

A prospective long-term follow-up of a cohort of live-born VLBW children and their controls studied repeatedly since birth and now assessed at 26-28 years of age. Of the totally 80 girls enrolled from birth 49 women (24 VLBW women and 25 controls) participated in the current follow-up. The women's anthropometric data and serum hormone levels were analysed.

RESULTS

The reproductive hormone levels, including Anti-Mullerian Hormone, did not differ significantly between VLBW women and their controls. Both groups reported menstrual cycle irregularities and pregnancies to the same extent but the VLBW women reported 1.5 years later age of menarche. The VLBW subjects had a catch-up growth within 18 months of birth but remained on average 5 cm shorter in adult height. There were no significant differences in BMI, sagittal abdominal diameter, blood pressure or in their answers regarding life style between the VLBW women and the controls.

CONCLUSION

No differences in the reproductive hormone levels were found between VLBW women and their controls. Although age at menarche was somewhat higher in the VLBW group menstrual cycles and pregnancy rates were similar in the VLBW and control groups. Further follow-up studies are required to elucidate the health outcomes of being born VLBW.

Metabolic Syndrome in Very Low Birth Weight Young Adults and Controls: The New Zealand 1986 VLBW Study

OBJECTIVE

To assess the physical well-being and components of the metabolic syndrome in a national cohort of very low birth weight (VLBW) young adults and same age controls.

STUDY DESIGN

The New Zealand VLBW Study cohort prospectively included all infants with birth weight <1500 g born in 1986, with 338 (82%) surviving to discharge home. Height and weight were measured at age 7-8 years. The VLBW cohort (n = 229; 71% alive) and term-born controls (n = 100) aged 27-29 years were clinically assessed in a single center over 2 days, including assessment for components of the metabolic syndrome.

RESULTS

Compared with controls, both male and female VLBW adults were significantly shorter (P < .001), but only females were lighter (P < .001) and had lower mean body mass index (P = .044), fat mass, and body fat percentage. Males, but not females, had significantly higher systolic blood pressure (P = .028), but there were no significant differences in other components of the metabolic syndrome. There was no difference in the prevalence of the metabolic syndrome in VLBW adults compared with controls (males, 22.2% vs 11.1%; P = .15: females, 12.8% vs 13.1%; P = .95). Examining the VLBW cohort with logistic regression, male sex, gestational age <28 weeks, Māori/Pacific Island ethnicity, and body mass index >90th percentile at age 7-8 years were significant predictors for the metabolic syndrome at age 27-29 years, with ORs of 2-4.

CONCLUSIONS

Systolic blood pressure in males was the only component of the metabolic syndrome that was significantly elevated in VLBW adults compared with controls. Extreme prematurity (<28 weeks) and body mass index >90th percentile at age 7-8 years were significant predictors of the metabolic syndrome at age 27-29 years.

TRIAL REGISTRATION

Registered at the Australian Clinical Trials Registry: ACTRN12612000995875.

Adult outcomes of being born late preterm or early term - What do we know?

The literature on adult outcomes of people born late preterm (LPT, 34-36 completed weeks) or early term (ET, 37-38 weeks) was reviewed. In PubMed, 9547 articles were identified; 53 were eligible. Of these, 12 were based on clinical cohorts, 32 on medical birth register linkages, and nine on historical birth cohorts; 48 out of 53 on Nordic countries; 50 out of 53 reported on LPT and eight out of 53 reported on ET. LPT plus ET have increased early (<45 years) adult all-cause mortality. Despite increased cardiometabolic risk factors and slightly lower cardiorespiratory fitness in LPT, no studies showed increased risk for coronary heart disease, some showed increased risk for stroke, and all showed increased risk for type 2 diabetes. Most show increased risk for asthma and decreased allergic rhinitis. LPT have slightly lower cognitive abilities and higher rates of several mental disorders; ET have intermediate values. LPT and ET adults have slightly lower education, occupational status, and income. We recommend that authors report findings of LPT/ET separately from those born more preterm.

Unrecognised and unmet physical health problems in a national cohort of very low birthweight young adults and controls

ABSTRACT INTRODUCTIONYoung adults are often reluctant to seek medical attention. Compared with full-term controls, very low birthweight (&lt;1500 g; VLBW) young adults may have more health problems. AIMTo assess the frequency of unrecognised or unmet physical health needs during a comprehensive health and welfare assessment of a national cohort of VLBW adults born in 1986 compared with full-term controls. METHODSThe VLBW cohort (n = 229; 71% of those alive) and controls (n = 100) aged 27–29 years were assessed in one University Hospital over 2 days. Physical health assessments included growth, respiratory function, blood pressure, echocardiogram, renal function, blood tests and an interview. Cranial MRI scans were performed on 150 VLBW adults and 50 controls. Significant unrecognised or unmet health needs were defined as including a body mass index (BMI) &gt;30 plus raised fasting insulin &gt;80 pmol/L; any two of moderate respiratory obstruction, or reduced diffusing capacity, or being a regular smoker; cardiovascular: hypertension or abnormal echocardiogram. RESULTSAmong the VLBW cohort and controls; 61% versus 73% (P &lt; 0.05) rated their overall health as very good or excellent. A general practitioner (GP) referral letter was sent for 44% VLBW adults and 38% controls, concerning metabolic problems in 20% and 17% respectively; respiratory problems in 12% and 4% (P &lt; 0.05) respectively; cardiovascular problems in 14% and 12% respectively; abnormal renal function in 7% in both groups; and anaemia in 3% and 5% respectively. DISCUSSIONUnrecognised or unmet health needs were frequent in both VLBW young adults and controls. Respiratory problems and hypertension were more frequent in the former. Continuity of care is important for VLBW adults who require a regular GP. GPs should routinely ask about gestation and birthweight and VLBW graduates should volunteer this information.

Comparison of physical activity and body composition in a cohort of children born extremely preterm or with extremely low birth weight to matched term-born controls: a follow-up study

OBJECTIVES

To compare physical activity and body composition in a cohort of children born extremely preterm/extremely low birth weight (EP/ELBW) with term-born (TB) controls.

METHODS

A regional cohort of children born during 1999-2000 at gestational age <28 weeks or with birth weight <1000 g and their individually matched TB controls were examined in 2010-2011. Information on physical activity was obtained from parental questionnaires, and body composition was determined by anthropometry and dual X-ray absorptiometry.

RESULTS

Fifty-seven EP/ELBW and 57 TB controls were included at a mean age of 11.6 years. Compared with the TB children, the EP/ELBW-born children exercised less often (22% vs 44% exercised more than 3 days per week), had lower physical endurance and poorer proficiency in sports and play and were less vigorous during exercise (p<0.05). They also had lower values (mean; 95 % CI) for muscle mass (0.9; 0.3-1.5 kg), total bone mineral density z-score (0.30; 0.13-0.52 units) and fat mass ratio (0.14; 0.06-0.21 units). The association between physical activity and bone mineral and skeletal muscle mass accrual was significantly weaker for the EP/ELBW-born than the TB children.

CONCLUSIONS

The EP/ELBW-born children were less physically active, had signs of an unfavourable body composition with less muscle mass and lower bone mineral density than the TB controls. The association between physical activity and the measures of body composition was weaker in the group of EP/ELBW-born children.

Trial of exercise to prevent HypeRtension in young adults (TEPHRA) a randomized controlled trial: study protocol

Background

Hypertension prevalence in young adults has increased and is associated with increased incidence of cerebrovascular and cardiovascular events in middle age. However, there is significant debate regards how to effectively manage young adult hypertension with recommendation to target lifestyle intervention. Surprisingly, no trials have investigated whether lifestyle advice developed for blood pressure control in older adults is effective in these younger populations.

Methods/Design

TEPHRA is an open label, parallel arm, randomised controlled trial in young adults with high normal and elevated blood pressure. The study will compare a supervised physical activity intervention consisting of 16 weeks structured exercise, physical activity self-monitoring and motivational coaching with a control group receiving usual care/minimal intervention. Two hundred young adults aged 18–35 years, including a subgroup of preterm born participants will be recruited through open recruitment and direct invitation. Participants will be randomised in a ratio of 1:1 to either the exercise intervention group or control group. Primary outcome will be ambulatory blood pressure monitoring at 16 weeks with measure of sustained effect at 12 months. Study measures include multimodal cardiovascular assessments; peripheral vascular measures, blood sampling, microvascular assessment, echocardiography, objective physical activity monitoring and a subgroup will complete multi-organ magnetic resonance imaging.

Discussion

The results of this trial will deliver a novel, randomised control trial that reports the effect of physical activity intervention on blood pressure integrated with detailed cardiovascular phenotyping in young adults. The results will support the development of future research and expand the evidence-based management of blood pressure in young adult populations.

Trial Registration

Clinicaltrials.gov registration number NCT02723552, registered on 30 March, 2016.

Polycystic ovary syndrome and risk factors for gestational diabetes

OBJECTIVE

To study the roles of self-reported symptoms and/or prior diagnosis of polycystic ovary syndrome (PCOS) and other potential risk factors for gestational diabetes mellitus (GDM) and to clarify whether the screening of GDM in early pregnancy is beneficial for all women with PCOS.

DESIGN

The FinnGeDi multicentre case-control study including 1146 women with singleton pregnancies diagnosed with GDM and 1066 non-diabetic pregnant women. There were 174 women with PCOS (symptoms and/or diagnosis self-reported by a questionnaire) and 1767 women without PCOS (data missing for 271).

METHODS

The study population (N = 1941) was divided into four subgroups: GDM + PCOS (N = 105), GDM + non-PCOS (N = 909), non-GDM + PCOS (N = 69), and controls (N = 858). The participants' characteristics and their parents' medical histories were compared.

RESULTS

The prevalence of PCOS was 10.4% among GDM women and 7.4% among non-diabetics (odds ratios (OR) 1.44, 95% CI: 1.05-1.97), but PCOS was not an independent risk for GDM after adjustments for participants' age and pre-pregnancy BMI (OR 1.07, 95% CI: 0.74-1.54). In a multivariate logistic regression analysis, the most significant parameters associated with GDM were overweight, obesity, age ≥35 years, participant's mother's history of GDM, either parent's history of type 2 diabetes (T2D) and participant's own preterm birth.

CONCLUSIONS

The increased risk of GDM in women with PCOS was related to obesity and increased maternal age rather than to PCOS itself, suggesting that routine early screening of GDM in PCOS women without other risk factors should be reconsidered. Instead, family history of GDM/T2D and own preterm birth were independent risk factors for GDM.

Leptin and IGF-1 in relation to body composition and bone mineralization of preterm-born children from infancy to 8 years

OBJECTIVE

Preterm birth has been associated with altered body composition, especially increased fat mass (FM) and decreased bone mineralization, and leptin and IGF-1 have been suggested to be involved in the regulation of both. We aimed to study the interplay between leptin, IGF-1, FM and bone mineralization measured in infancy and childhood of children born preterm.

DESIGN

Observational study.

PATIENTS/SUBJECTS

Seventy-nine (40 boys) preterm-born children (gestational age ≤32 weeks and/or birth weight ≤1500 g) aged 8 years.

MEASUREMENTS

Serum leptin and IGF-1 were measured at term age, at 3- and 6-month corrected age (CA), and 8 years. Body composition (fat and lean mass) and bone parameters (bone area, mineral content and density) were measured by Dual-energy X-ray Absorptiometry (DXA) at term age, 6-month CA and 8 years.

RESULTS

Leptin was positively associated with FM at all time points and with bone parameters at term age and 6-month CA. IGF-1 was associated with body composition and bone density at most of the time points. Explained variation in bone mineralization increased significantly by adding bone area (BA) and height to the models.

CONCLUSIONS

During infancy and childhood, leptin and IGF-1 were associated with body composition in preterm-born children. In addition, leptin was associated with bone parameters in early infancy, but not in childhood. It is hypothesized that a complicated interplay between multiple pathways, which most likely changes over time, is involved in regulation of body composition and bone mineralization of preterm-born infants.

11β-HSD1 in Human Fetal Membranes as a Potential Therapeutic Target for Preterm Birth

Human parturition is a complex process involving interactions between the myometrium and signals derived from the placenta, fetal membranes, and fetus. Signals originating from fetal membranes are crucial components that trigger parturition, which is clearly illustrated by the labor-initiating consequence of membrane rupture. It has been recognized for a long time that among fetal tissues in late gestation the fetal membranes possess the highest capacity for cortisol regeneration by 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1). However, the exact role of this unique feature remains a mystery. Accumulating evidence indicates that this extra-adrenal source of cortisol may serve as an upstream signal for critical events in human parturition, including enhanced prostaglandin and estrogen synthesis as well as extracellular matrix remodeling. This may explain why such high capacity for cortisol regeneration develops in human fetal membranes at late gestation. Therefore, inhibition of 11β-HSD1 may provide a potential therapeutic target for prevention of preterm birth. This review summarizes the current understanding of the functional role of cortisol regeneration by 11β-HSD1 in human fetal membranes.

The superovulated environment, independent of embryo vitrification, results in low birthweight in a mouse model

Epidemiological studies suggest that babies born following in vitro fertilization (IVF) and fresh embryo transfer are of lower birthweight than babies born following frozen embryo transfer, although the mechanism responsible for this phenotype is not known. We developed a novel mouse model that isolates the independent effects of embryo freezing and the superovulated environment, which cannot be performed in humans. We transferred blastocysts that had been vitrified and warmed, mixed with with fresh blastocysts, into individual pseudopregnant recipients produced by either natural mating or mating following injection with equine chorionic gonadotropin and human chorionic gonadotropin and hCG (superovulation). We found that superovulation of the recipient dams led to significantly lower fetal weight at term while blastocyst vitrification had no significant effect on fetal weight (1.43 ± 0.24 g fresh-natural, 1.30 ± 0.28 g vitrified-natural vs. 1.09 ± 0.20 fresh-superovulated, 0.93 ± 0.23 g vitrified-superovulated, P < 0.0001). Doppler ultrasound revealed increased median umbilical artery resistance in the placentae of near-term dams exposed to superovulation compared to naturally mated dams (0.927 vs 0.904, P = 0.02). Additionally, placental microvascular density was lower in superovulated compared to naturally mated dams (1.24 × 10-3 vessel/micron vs 1.46 × 10-3 vessels/micron, P = 0.046). Gene expression profiling suggested alterations in fetal genes involved in glucorticoid regulation. These results suggest a potential mechanism for altered birthweight following superovulation in our model and may have implications for human IVF.

Assessing Weight Gain by the 2009 Institute of Medicine Guidelines and Perinatal Outcomes in Twin Pregnancy

Objective The objective is to estimate the impact of maternal weight gain outside the 2009 Institute of Medicine recommendations on perinatal outcomes in twin pregnancies. Study Design Twin pregnancies with two live births between January 1, 2004 and December 31, 2014 delivered after 23 weeks Finger Lakes Region Perinatal Data System (FLRPDS) and Central New York Region Perinatal Data System were included. Women were classified into three groups using pre-pregnancy body mass index (BMI). Perinatal outcomes in women with low or excessive weekly maternal weight gain were assessed using normal weekly weight gain as the referent in each BMI group. Results Low weight gain increased the risk of preterm delivery, birth weight less than the 10th percentile for one or both twins and decreased risk of macrosomia across all BMI groups. There was a decreased risk of hypertensive disorders in women with normal pre-pregnancy weight and an increased risk of gestational diabetes with low weight gain in obese women. Excessive weight gain increased the risk of hypertensive disorders and macrosomia across all BMI groups and decreased the risk of birth weight less than 10th percentile one twin in normal pre-pregnancy BMI group. Conclusion Among twin pregnancies, low weight gain is associated with low birth weight and preterm delivery in all BMI groups and increased risk of gestational diabetes in obese women. Our study did not reveal any benefit from excessive weekly weight gain with potential harm of an increase in risk of hypertensive disorders of pregnancy. Normal weight gain per 2009 IOM guidelines should be encouraged to improve pregnancy outcome in all pre-pregnancy BMI groups.

Salt sensitivity of blood pressure at age 8 years in children born preterm

Preterm birth and low birth weight have been associated with an increased risk of hypertension; postnatal growth and dietary salt intake may contribute to these associations. In adults, the change of blood pressure (BP) in response to modifications in salt intake, i.e., salt sensitivity of BP, has been independently associated with cardiovascular disease. Little is known about salt sensitivity in children. We hypothesize that it may partly explain the association between preterm birth and higher BP in later life. We assessed salt sensitivity of BP at age 8 years in 63 preterm-born children, and explored its association with postnatal growth, sodium intake, and body composition from infancy onwards. BP was measured at baseline and after a 7-day high-salt diet. The difference in mean arterial pressure (MAP) was calculated; salt sensitivity was defined as an increase in MAP of ≥5%. Ten children (16%) showed salt sensitivity of BP, which was associated with neonatal growth restriction as well as with lower fat mass and BMI from infancy onwards. At age 8 years, children classified as salt sensitive had a lower weight-for-age SD-score (-1.5 ± 1.3 vs. -0.6 ± 1.1) and BMI (13.8 ± 1.7 vs. 15.5 ± 1.8 kg/m²) compared to their salt resistant counterparts. Sodium intake was not associated with (salt sensitivity of) BP. Salt sensitivity of BP was demonstrated in preterm-born children at age 8 years and may contribute to the development of cardiovascular disease at later age. Long-term follow-up studies are necessary to assess reproducibility of our findings and to explore clustering with other cardiovascular risk factors.

Neonatal Nutrition Predicts Energy Balance in Young Adults Born Preterm at Very Low Birth Weight

Epidemiological studies and animal models suggest that early postnatal nutrition and growth can influence adult health. However, few human studies have objective recordings of early nutrient intake. We studied whether nutrient intake and growth during the first 9 weeks after preterm birth with very low birth weight (VLBW, <1500 g) predict total energy intake, resting energy expenditure (REE), physical activity and food preferences in young adulthood. We collected daily nutritional intakes and weights during the initial hospital stay from hospital records for 127 unimpaired VLBW participants. At an average age 22.5 years, they completed a three-day food record and a physical activity questionnaire and underwent measurements of body composition (dual X-ray absorptiometry; n = 115 with adequate data) and REE (n = 92 with adequate data). We used linear regression and path analysis to investigate associations between neonatal nutrient intake and adult outcomes. Higher energy, protein and fat intakes during the first three weeks of life predicted lower relative (=per unit lean body mass) energy intake and relative REE in adulthood, independent of other pre- and neonatal factors. In path analysis, total effects of early nutrition and growth on relative energy intake were mostly explained by direct effects of early life nutrition. A path mediated by early growth reached statistical significance only for protein intake. There were no associations of neonatal intakes with physical activity or food preferences in adulthood. As a conclusion, higher intake of energy and nutrients during first three weeks of life of VLBW infants predicts energy balance after 20 years. This association is partly mediated through postnatal growth.

Leisure Time Physical Activity in Young Adults Born Preterm

OBJECTIVE

To evaluate the amount of self-reported physical activity in young adults born prematurely compared with those born at term.

STUDY DESIGN

Unimpaired participants of the Preterm Birth Study (Preterm Birth and Early Life Programming of Adult Health and Disease) birth cohort study were studied at age 23.3 ± 1.2 (SD) years: 118 born early preterm (<34 weeks), 210 late preterm (34-36 weeks), and 311 born at term (≥37 weeks, controls). The participants completed a validated 30-item, 12-month physical activity questionnaire. The annual frequency and total volume of conditioning and nonconditioning leisure time physical activity and commuting physical activity were calculated and the data analyzed by means of linear regression.

RESULTS

Adults born early preterm reported a 31.5% (95% CI, 17.4-43.2) lower volume of leisure time physical activity (in metabolic equivalents [MET] h/year) and had a 2.0-fold increased OR (1.2-3.3) of being in the least active quintile than controls. Lower amounts of conditioning, nonconditioning, and commuting physical activity all contributed to the difference. In addition, early preterm participants undertook less vigorous physical activity (≥6 MET). No differences in physical activity were found between the late preterm and control groups. Adjustments for potential early life confounders and current mediating health characteristics did not change the results.

CONCLUSIONS

Young adults born early preterm engage less in leisure time physical activities than peers born at term. This finding may in part underlie the increased risk factors of cardiometabolic and other noncommunicable diseases in adults born preterm. Low physical activity is a risk factor for several noncommunicable diseases and amenable to prevention.

Birth weight and postnatal growth in preterm born children are associated with cortisol in early infancy, but not at age 8 years

BACKGROUND

Preterm birth has been associated with altered hypothalamic-pituitary-adrenal (HPA-) axis activity as well as cardiometabolic diseases and neurodevelopmental impairments later in life. We assessed cortisol from term age to age 8 y in children born preterm, to explore the development of HPA-axis activity in association with intrauterine and early-postnatal growth until 6 mo. corrected age.

METHODS

In 152 children born at a gestational age ≤32 wks. and/or with a birth weight ≤1,500g, random serum cortisol was assessed at term age (n=150), 3 mo. (n=145) and 6 mo. corrected age (n=144), and age 8 y (n=59). Salivary cortisol was assessed at age 8 y (n=75): prior to bedtime, at awakening, 15min after awakening, and before lunch. Cortisol was analyzed in association with birth weight-standard deviation score (SDS), being born small for gestational age (SGA), and combinations of intrauterine and postnatal growth: appropriate for gestational age (AGA) with or without growth restriction (AGA GR+ or AGA GR-) at 6 mo. corrected age, and SGA with or without catch-up growth (SGA CUG+ or SGA CUG-) at 6 mo. corrected age. Cross-sectional associations at all time points were analyzed using linear regression, and longitudinal associations were analyzed using generalized estimating equations.

RESULTS

Longitudinally, birth weight-SDS was associated with cortisol (β [95%CI]): lower cortisol over time was seen in infants with a birth weight ≤-2 SDS (-50.69 [-94.27; -7.11], p=0.02), infants born SGA (-29.70 [-60.58; 1.19], p=0.06), AGA GR+ infants (-55.10 [-106.02; -4.17], p=0.03) and SGA CUG- infants (-61.91 [-104.73; -19.10], p=0.01). In cross-sectional analyses at age 8 y, no associations were found between either serum or salivary cortisol and birth weight-SDS, SGA-status, or growth from birth to 6 mo. corrected age.

CONCLUSION

In children born preterm, poor intrauterine and postnatal growth were associated with lower cortisol in early infancy, but not at age 8 y. Even though HPA-axis activity no longer differed between groups at age 8 y, or differences could not be confirmed due to attrition, it is unknown whether the differences found in early infancy could attribute to increased health risks later in life.

Follow-up of a randomized trial on postdischarge nutrition in preterm-born children at age 8 y

Background: Early nutritional interventions may modulate health risks in preterm-born infants. Previously, we showed that preterm-born infants fed an isocaloric protein- and mineral-enriched postdischarge formula (PDF) from term age to 6-mo corrected age (CA) gained more lean mass than did those fed term formula (TF). Long-term follow-up of randomized nutritional trials is important to test the hypothesis that short-term positive effects on health are sustainable.Objective: The aim of this follow-up study was to compare body size, body composition, and metabolic health at age 8 y in preterm-born children who were randomly assigned to receive either PDF or TF from term age until 6-mo CA.Design: A total of 79 of 152 children (52%) from the original randomized controlled trial were enrolled for follow-up at age 8 y. Weight, height, and head circumference were measured by using standard methods. Body composition, including fat mass, lean mass, bone mineral content, and bone mineral density, was determined by dual-energy X-ray absorptiometry. Blood pressure was measured in the supine position by using an automatic device. Metabolic variables, including glucose, insulin, insulin-like growth factor I, triglycerides, cholesterol, cortisol, and leptin, were measured after an overnight fast. Nutritional habits at age 8 y were assessed by using a 3-d nutritional diary.Results: At age 8 y, no differences were found in body size, body composition, bone variables, and metabolic health variables when comparing children fed PDF with those fed TF. Adjustment for known and possible confounders did not change these results.Conclusions: In this follow-up study in preterm-born children, we showed that the favorable effects of PDF at 6-mo CA either were not maintained or could not be confirmed because of attrition at the age of 8 y. We suggest that future research should focus on nutritional interventions in the pre- and postdischarge period as a continuum rather than as separate entities. This trial was registered at www.trialregister.nl as NTR 2972 (follow-up study [STEP-2 (Study Towards the Effects of Post-discharge Nutrition 2)]) and NTR 55 [original randomized controlled trial (STEP)].

Is HPA axis reactivity in childhood gender-specific? A systematic review

BACKGROUND

In adults, hypothalamus-pituitary-adrenal (HPA) axis activity shows sexual dimorphism, and this is thought to be a mechanism underlying sex-specific disease incidence. Evidence is scarce on whether these sex differences are also present in childhood. In a meta-analysis, we recently found that basal (non-stimulated) cortisol in saliva and free cortisol in 24-h urine follow sex-specific patterns. We explored whether these findings could be extended with sex differences in HPA axis reactivity.

METHODS

From inception to January 2016, PubMed and EMBASE.com were searched for studies that assessed HPA axis reactivity in healthy girls and boys aged ≤18 years. Articles were systematically assessed and reported in the categories: (1) diurnal rhythm, (2) cortisol awakening response (CAR), (3) protocolled social stress tests similar or equal to the Trier Social Stress Test for children (TSST-C), (4) pharmacological (ACTH and CRH) stress tests, and (5) miscellaneous stress tests.

RESULTS

Two independent assessors selected 109 out of 6158 records for full-text screening, of which 81 studies (with a total of 14,591 subjects) were included. Studies showed that girls had a tendency towards a more variable diurnal rhythm (12 out of 29 studies), a higher CAR (8 out of 18 studies), and a stronger cortisol response to social stress tests (9 out of 21 studies). We found no evidence for sex differences in cortisol response after a pharmacological challenge or to miscellaneous stress tests.

DISCUSSION

Sex differences in HPA axis reactivity appear to be present in childhood, although evidence is not unequivocal. For a better evaluation of sex differences in HPA axis reactivity, standardization of protocols and reports of stress tests is warranted.

The evolution of modern respiratory care for preterm infants

Preterm birth rates are rising, and many preterm infants have breathing difficulty after birth. Treatments for infants with prolonged breathing difficulty include oxygen therapy, exogenous surfactant, various modes of respiratory support, and postnatal corticosteroids. In this Series paper, we review the history of neonatal respiratory care and its effect on long-term outcomes, and we outline the future direction of the research field. The delivery and monitoring of oxygen therapy remains controversial, despite being in use for more than 50 years. Exogenous surfactant replacement has been used for 25 years and has dramatically reduced mortality and morbidity, but more research on when and how it is administered is needed. Methods and techniques of neonatal respiratory support are evolving. Clinicians are moving away from routine intubation and ventilation, and new modes of non-invasive support are being investigated. Postnatal corticosteroids have a limited role in infants with evolving bronchopulmonary dysplasia, but more research is needed to identify the best timing, type, dose, and method of administration. Despite advances in neonatal care in the past 50 years, bronchopulmonary dysplasia, with all its adverse short-term and long-term consequences, is still a serious problem in neonatal care. The challenge remains to support breathing in preterm infants, with special attention to risk factors in the subpopulation of infants that are at highest risk of bronchopulmonary dysplasia, without damaging their lungs or adversely affecting their long-term health.

Prenatal determinants of physical activity and cardiorespiratory fitness in adolescence - Northern Finland Birth Cohort 1986 study

BACKGROUND

Lower levels of physical activity and cardiorespiratory fitness are key risk factors of chronic adult diseases. Physical activity and cardiorespiratory fitness are predicted by birth weight, but the underlying parental and pregnancy-related factors remain largely unknown. We examined how prenatal determinants are associated with physical activity and cardiorespiratory fitness in adolescence.

METHODS

Of the 16-year-old members of the population-based Northern Finland Birth Cohort 1986 (NFBC 1986), 6682 singletons with no major physical disability reported their amount of physical activity outside school hours, and 4706 completed a submaximal cycle ergometer test assessing cardiorespiratory fitness. Physical activity was expressed as metabolic equivalent hours per week (METh/week) and cardiorespiratory fitness as peak oxygen uptake (ml·kg-1·min-1). Prenatal determinants included birth weight, length of gestation, mother's and father's body mass index (BMI), maternal gestational diabetes mellitus (GDM), and maternal hypertension and smoking during pregnancy. Data were analyzed by multiple linear regression.

RESULTS

A higher birth weight and longer length of gestation predicted lower levels of physical activity and cardiorespiratory fitness at 16 years, although the association between length of gestation and physical activity was inverse U-shaped. Mother's or father's overweight or obesity before pregnancy were associated with lower levels of their offspring's physical activity and fitness in adolescence. Adjusting for maternal pregnancy disorders and the adolescent's own BMI attenuated the associations with the mother's but not the father's overweight/obesity. Furthermore, maternal GDM predicted lower cardiorespiratory fitness.

CONCLUSIONS

A high birth weight and parental overweight/obesity are associated with lower levels of both physical activity and cardiorespiratory fitness in adolescence, while maternal GDM and longer length of gestation are associated with lower cardiorespiratory fitness. Both long and short lengths of gestation predict low physical activity.

Self-Reported Mental Health Problems Among Adults Born Preterm: A Meta-analysis

CONTEXT

Preterm birth increases the risk for mental disorders in adulthood, yet findings on self-reported or subclinical mental health problems are mixed.

OBJECTIVE

To study self-reported mental health problems among adults born preterm at very low birth weight (VLBW; ≤1500 g) compared with term controls in an individual participant data meta-analysis.

DATA SOURCES

Adults Born Preterm International Collaboration.

STUDY SELECTION

Studies that compared self-reported mental health problems using the Achenbach Young Adult Self Report or Adult Self Report between adults born preterm at VLBW (n = 747) and at term (n = 1512).

DATA EXTRACTION

We obtained individual participant data from 6 study cohorts and compared preterm and control groups by mixed random coefficient linear and Tobit regression.

RESULTS

Adults born preterm reported more internalizing (pooled β = .06; 95% confidence interval .01 to .11) and avoidant personality problems (.11; .05 to .17), and less externalizing (-.10; -.15 to -.06), rule breaking (-.10; -.15 to -.05), intrusive behavior (-.14; -.19 to -.09), and antisocial personality problems (-.09; -.14 to -.04) than controls. Group differences did not systematically vary by sex, intrauterine growth pattern, neurosensory impairments, or study cohort.

LIMITATIONS

Exclusively self-reported data are not confirmed by alternative data sources.

CONCLUSIONS

Self-reports of adults born preterm at VLBW reveal a heightened risk for internalizing problems and socially avoidant personality traits together with a lowered risk for externalizing problem types. Our findings support the view that preterm birth constitutes an early vulnerability factor with long-term consequences on the individual into adulthood.

Objectively measured physical activity and sedentary time in young adults born preterm-The ESTER study

BACKGROUND

Young adults born preterm have higher levels of cardio metabolic risk factors and they report less physical activity than their peers born at term. Physical activity provides important cardio metabolic health benefits. We hypothesized that objectively measured physical activity levels are lower and time spent sedentary is higher among preterm-born individuals compared with controls.

METHODS

We studied unimpaired participants of the ESTER birth cohort study at age 23.3 y (SD: 1.2): 60 born early preterm (<34 wk), 108 late preterm (34-36 wk), and 178 at term (controls). Physical activity and sedentary time were measured by hip-worn accelerometer (ActiGraph).

RESULTS

As compared with controls' (mean physical activity, 303 counts per minute (cpm; SD 129)), physical activity was similar among adults born early preterm (mean difference = 21 cpm, 95% CI -61, 19) or late preterm (5 cpm, -27, 38). Time spent sedentary was also similar. Adjustments for early life confounders or current mediating characteristics did not change the results.

CONCLUSION

In contrast to our hypothesis, we found no difference in objectively measured physical activity or time spent sedentary between adults born preterm and at term. The previously reported differences may be limited to physical activity captured by self-report.

Association Between Preterm Birth and Lower Adult Height in Women

We examined whether being born preterm was associated with changes in adult anthropometry in women. We assessed data on 201,382 women (born in 1973-1988) from the Swedish Birth Register. The mean age was 26.0 years. Of the women in our cohort, 663 were born very preterm (<32 weeks of gestation), 8,247 were born moderately preterm (at least 32 weeks but <37 weeks), and 192,472 were born at term (37-41 weeks). Subgroup analyses were carried out among siblings and also after adjustment for maternal anthropometric data. Statistical tests were 2-sided. Decreasing gestational age was associated with lower height (-1.1 mm per week of gestation; P < 0.0001), so that women who were born very preterm were on average 12 mm shorter than women who were born moderately preterm (P < 0.0001) and 17 mm shorter than women born at term (P < 0.0001). Compared with women who were born at term, those who were born very preterm had 2.9 times higher odds of short stature (<155.4 cm), and those born moderately preterm had 1.43 times higher odds. Subgroup analyses showed no differences between women born moderately preterm and those born at term but accentuated differences from women born very preterm. Among siblings (n = 2,388), very preterm women were 23 mm shorter than those born at term (P = 0.003), with a 20-mm difference observed in subgroup analyses (n = 27,395) that were adjusted for maternal stature (P < 0.001). A shorter final height was associated with decreasing gestational age, and this association was particularly marked in women born very preterm.

Review: Eicosanoids in preterm labor and delivery: Potential roles of exosomes in eicosanoid functions

Preterm delivery is a major obstetric health problem contributing to poor neonatal outcome including low birth weight, respiratory distress syndrome, gastrointestinal, immunologic, central nervous system, hearing, and vision problems. Worldwide, approximately 15 million babies are born prematurely each year. The critical question which remains is how to identify women destined to deliver preterm from those who will achieve a term delivery. Prostaglandins, in all mammals, are important in the parturient process. Increased intrauterine prostaglandin production is associated with labor and in fact prostaglandin E₂ (PGE₂) or analogs are widely used clinically for cervical ripening and labor induction. Measurements of circulating eicosanoids have been problematic because of the rapid and major clearance by the lungs and then kidneys resulting in very low concentrations in plasma. Moreover, since eicosanoids are produced by all mammalian tissues, the sources of the measured eicosanoids are unknown. Our understanding of how cells communicate has undergone a paradigm shift with the recognition of the role of exosomes in intercellular signaling. Recent publications have identified enzymes and products of arachidonic acid metabolism (eicosanoids) within exosomes. This review will explore the potential roles of exosomes in eicosanoid functions that are critical in preterm labor and delivery.