Preterm birth, low birth weight, and risk for esophageal adenocarcinoma

Causal effects of genetic birth weight and gestational age on adult esophageal diseases: Mendelian randomization study

BACKGROUND

Few studies have investigated the association between gestational age, birth weight, and esophageal cancer risk; however, causality remains debated. We aimed to establish causal links between genetic gestational age and birth weight traits and gastroesophageal reflux disease (GERD), Barrett's esophagus (BE), and esophageal adenocarcinoma (EA). Additionally, we explored if known risk factors mediate these links.

AIM

To analyze of the relationship between gestational age, birth weight and GERD, BE, and EA.

METHODS

Genetic data on gestational age and birth weight (n = 84689 and 143677) from the Early Growth Genetics Consortium and outcomes for GERD (n = 467253), BE (n = 56429), and EA (n = 21271) from genome-wide association study served as instrumental variables. Mendelian randomization (MR) and mediation analyses were conducted using MR-Egger, weighted median, and inverse variance weighted methods. Robustness was ensured through heterogeneity, pleiotropy tests, and sensitivity analyses.

RESULTS

Birth weight was negatively correlated with GERD and BE risk [odds ratio (OR) = 0.78; 95% confidence interval (CI): 0.69-0.8] and (OR = 0.75; 95%CI: 0.60-0.9), respectively, with no significant association with EA. No causal link was found between gestational age and outcomes. Birth weight was positively correlated with five risk factors: Educational attainment (OR = 1.15; 95%CI: 1.01-1.31), body mass index (OR = 1.06; 95%CI: 1.02-1.1), height (OR = 1.12; 95%CI: 1.06-1.19), weight (OR = 1.13; 95%CI: 1.10-1.1), and alcoholic drinks per week (OR = 1.03; 95%CI: 1.00-1.06). Mediation analysis showed educational attainment and height mediated the birth weight-BE link by 13.99% and 5.46%.

CONCLUSION

Our study supports the protective role of genetically predicted birth weight against GERD, BE, and EA, independent of gestational age and partially mediated by educational attainment and height.

Genetic estimation of correlations and causalities between multifaceted modifiable factors and gastro-oesophageal reflux disease

BACKGROUND

Gastro-oesophageal reflux disease (GORD) is a common gastrointestinal dysfunction that significantly affects the quality of daily life, and health interventions are challenging to prevent the risk of GORD. In this study, we used Mendelian randomization framework to genetically determine the causal associations between multifaceted modifiable factors and the risk of GORD.

MATERIALS AND METHODS

Sixty-six exposures with available instrumental variables (IVs) across 6 modifiable pathways were included in the univariable MR analysis (UVMR). Summary-level genome-wide association studies (GWAS) datasets for GORD were retrieved from the Neale Lab (GORD _Neale , Ncases = 29975, Ncontrols = 390556) and FinnGen (GORD _Finn , Ncases = 13141, Ncontrols = 89695). Using the METAL software, meta-analysis for single nucleotide polymorphisms (SNPs) from GORD _Neale and GORD _Finn was conducted with an inverse variance weighted (IVW) fixed-effect model. Moreover, we leveraged partition around medoids (PAM) clustering algorithm to cluster genetic correlation subtypes, whose hub exposures were conditioned for multivariable MR (MVMR) analyses. P-values were adjusted with Bonferroni multiple comparisons.

RESULTS

Significant causal associations were identified between 26 exposures (15 risk exposures and 11 protective exposures) and the risk of GORD. Among them, 13 risk exposures [lifetime smoking, cigarette consumption, insomnia, short sleep, leisure sedentary behavior (TV watching), body mass index (BMI), body fat percentage, whole body fat mass, visceral adipose tissue, waist circumference, hip circumference, major depressive disorder, and anxious feeling], and 10 protective exposures (leisure sedentary behavior (computer use), sitting height, hand grip strength (left and right), birth weight, life satisfaction, positive affect, income, educational attainment, and intelligence) showed novel significant causal associations with the risk of GORD. Moreover, 13 exposures still demonstrated independent associations with the risk of GORD following MVMR analyses conditioned for hub exposures (educational attainment, smoking initiation and BMI). In addition, 12 exposures showed suggestive causal associations with the risk of GORD.

CONCLUSION

This study systematically elucidated the modifiable factors causally associated with the risk of GORD from multifaceted perspectives, which provided implications for prevention and treatment of GORD.

Symptom Scores and pH-Impedance: Secondary Analysis of a Randomized Controlled Trial in Infants Treated for Gastroesophageal Reflux

BACKGROUND AND AIMS

To evaluate and compare gastro-esophageal reflux (GER) symptom scores with pH-impedance and test the effects of acid-suppressive medications with or without feeding modifications on pH-impedance in high-risk infants.

METHODS

Infant Gastroesophageal Reflux Questionnaire Revised (I-GERQ-R) and 24-hour pH-impedance data were analyzed from 94 infants evaluated in a tertiary care setting for GER disease. Longitudinal data from 40 infants that received randomized GER therapy (proton pump inhibitor [PPI] with or without feeding modifications) for 4 weeks followed by 1-week washout were analyzed. Relationships between I-GERQ-R and pH-impedance metrics (acid reflux index, acid and bolus GER events, distal baseline impedance, and symptoms) were examined and effects of treatments compared.

RESULTS

(A) Correlations between I-GERQ-R and pH-impedance metrics were weak. (B) I-GERQ-R sensitivity, specificity, and positive predictive values were suboptimal when correlated with pH-impedance metrics. I-GERQ-R negative predictive value (NPV) was high for acid symptom-association probability (NPV = 84%) and distal baseline impedence (NPV = 86%) thresholds. (C) PPI with feeding modifications (vs PPI alone) did not alter pH-impedance metrics or symptom scores (P > .05); however, bolus clearance metrics worsened for both treatment groups (P < .05).

CONCLUSIONS

In high-risk infants (1) I-GERQ-R may be a helpful clinical screening tool to exclude acid-GER disease diagnosis and minimize unnecessary acid-suppressive treatment, but further testing is needed for diagnosis. (2) Acid-suppressive therapy with feeding modifications has no effect on symptom scores or pH-impedance metrics. Clearance of refluxate worsened despite PPI therapy, which may signal development of pharyngoesophageal dysmotility and persistence of symptoms. (3) Placebo-controlled trials are needed in high-risk infants with objective pH-impedance criteria to determine efficacy, safety, and underlying mechanisms. Clinicaltrials.gov ID: NCT02486263.

Preterm birth, neonatal therapies and the risk of childhood cancer

Our aim was to study the impact of preterm birth and neonatal therapies on the risk of childhood cancer using a nationwide, registry-based, case-control design. Combining population-based data from Finnish Medical Birth Registry (MBR) and Finnish Cancer Registry, we identified a total of 2029 patients diagnosed with cancer under the age of 20 years and 10 103 age- and sex-matched controls over the years 1996 to 2014. Information on the prenatal and perinatal conditions was obtained from the MBR. Gestational age was categorized into early (<32) and late preterm (32-36) and term (≥37 weeks). Cancer risk among the preterm compared to term neonates was evaluated using conditional logistic regression. We identified 141 cancers among the preterm (20.8% of 678) vs 1888 cancers in the term children (16.5% of 11 454). The risk of any cancer was increased for the preterm (odds ratio [OR] 1.28, 95% confidence interval [CI] 1.06-1.57), especially for the early preterm (OR 1.84, 95% CI 1.16-2.92). The risk of acute myeloid leukemia (AML; OR 2.33, 95% CI 1.25-4.37), retinoblastoma (OR 3.21, 95% CI 1.22-8.41) and germ cell tumors (OR 5.89, 95% CI 2.29-15.18) was increased among the preterm compared to term. Germ cell tumors were diagnosed at a significantly younger age among the preterm. Neonatal therapies, for example, mechanical ventilation, were associated with an increased risk of childhood cancer independent of gestational age. Preterm, especially early preterm birth, is associated with an increased risk of childhood cancer, especially germ cell tumors and AML. Respiratory distress requiring neonatal intervention also appears to be associated with an increased risk.

Cohort profile: ESPRESSO (Epidemiology Strengthened by histoPathology Reports in Sweden)

The ESPRESSO study constitutes a novel approach to examine the etiology and prognosis of gastrointestinal disease in which histopathology plays a prominent role. Between 2015 and 2017, all pathology departments (n=28) in Sweden were contacted and asked to procure histopathology record data from the gastrointestinal tract (pharynx to anus), liver, gallbladder, and pancreas. For each individual, local histopathology IT personnel retrieved data on personal identity number, date of histopathology, topography (where the biopsy is taken), morphology (biopsy appearance), and where available free text. In total, between 1965 and 2017, histopathology record data were available in 2.1 million unique individuals, but the number of data entries was 6.1 million because more than one biopsy was performed in many of the study participants. Index individuals with histopathology data were matched with up to five controls from the general population. We also identified all first-degree relatives (parents, children, full siblings), and the index individual's first spouse. The total study population consisted of 13.0 million individuals. Data from all the study participants have been linked to Swedish National Healthcare Registers allowing research not only on such aspects as fetal and perinatal conditions and the risk of future gastrointestinal disease but also on the risk of comorbidity and complications (including cancer and death). Furthermore, the ESPRESSO database allows researchers and practitioners to identify diagnoses and disease phenotypes not currently indexed in national registers (including disease precursors). The ESPRESSO database increases the sensitivity and specificity of already-recorded diseases in the national health registers. This paper is an overview of the ESPRESSO database.

Risk factors for Barrett's esophagus

Barrett's esophagus (BE) is a well-recognized precursor of esophageal adenocarcinoma (EAC) and is defined as ≥1 cm segment of salmon-colored mucosa extending above the gastroesophageal junction into the tubular esophagus with biopsy confirmation of metaplastic replacement of the normal squamous epithelium by intestinal-type columnar epithelium. The incidence of both BE and EAC has been increasing over the past few decades. As a result, preventing the development of BE by identifying and understanding its modifiable and non-modifiable risk factors may help reduce the incidence of EAC. Over the recent past, a tremendous amount of progress has been made towards improving our knowledge of risk factors and pathogenesis of BE. This article reviews the evidence for the various risk factors for developing BE.

Premature Birth and Large for Gestational Age Are Associated with Risk of Barrett's Esophagus in Adults

BACKGROUND

Birth characteristics, including weight and gestational age, may be associated with risk of Barrett's esophagus (BE), the only known precursor for esophageal adenocarcinoma; however, data are limited.

AIMS

To examine associations between various birth characteristics and BE, and whether these associations are mediated by known risk factors for BE.

METHODS

Data were obtained from a cross-sectional study among eligible Veterans Affairs patients scheduled for an upper endoscopy, and a sample identified from primary care clinics. Participants underwent an esophagogastroduodenoscopy and completed a survey that captured information on sociodemographic and clinical factors, as well as birth information. We compared 263 patients with histologically confirmed BE to 1416 controls without BE on endoscopy. Odds ratios (ORs) and 95 % confidence intervals (CIs) were calculated using multivariate logistic regression.

RESULTS

Premature birth was independently associated with risk of BE after adjusted by age, sex, race, and other birth characteristics (OR 3.28, 95 % CI 1.22-8.79). On the other hand, large for gestational age was inversely associated with risk of BE (OR 0.46, 95 % CI 0.21-0.98). These effects were stronger for patients with long-segment BE than with short-segment BE. The associations were not mediated by gastroesophageal reflux disease symptoms, use of proton pump inhibitors, Helicobacter Pylori infection, waist-hip-ratio, height or the presence of hiatus hernia.

CONCLUSIONS

Premature birth and large for gestational age may be associated with risk of BE in adults. These associations do not appear to be mediated through known risk factors for BE; however, additional studies are required to confirm our findings.

Increased risk of Barrett's esophagus among individuals born preterm or small for gestational age

BACKGROUND & AIMS

Gastroesophageal reflux is common in infants during their first year of life, especially in those born preterm or small for gestational age (SGA). We assessed whether being born preterm or SGA increased the risk of developing Barrett's esophagus (BE) in adulthood.

METHODS

We performed a population-based case-control study of patients with BE (cases) that were diagnosed at 2 Swedish hospitals from January 1, 1986, through December 31, 2005. We identified the birth hospital of the cases; data on perinatal characteristics such as gestational age at birth and birth weight were collected from original birth records. We also obtained and collected information on the 3 singleton live births, of the same sex, born after each case at the same maternity ward (controls). In total, we analyzed data from 331 cases and 852 matched controls. We used conditional logistic regression to determine odds ratios (ORs), determined 95% confidence intervals (CIs), and adjusted for potential confounding factors.

RESULTS

Compared with infants born with a normal birth weight (3000-3999 g), infants with low birth weight (<2500 g) were at increased risk of BE (adjusted OR, 8.22; 95% CI, 2.83-23.88). This was mainly due to an effect of SGA rather than preterm birth. Specifically, compared with infants with normal birth weight for gestational age (25th-75th percentiles), the odds of BE among very SGA infants (<3rd percentile) was nearly tripled (adjusted OR, 2.95; 95% CI, 1.35-6.44).

CONCLUSIONS

On the basis of a population-based study of patients with BE in Sweden, infants born SGA have a 3-fold increase in risk for developing BE as adults, compared with infants of normal birth weight for gestational age.

Associations between antibiotic exposure during pregnancy, birth weight and aberrant methylation at imprinted genes among offspring

Objectives:

Low birth weight (LBW) has been associated with common adult-onset chronic diseases, including obesity, cardiovascular disease, type II diabetes and some cancers. The etiology of LBW is multi-factorial. However, recent evidence suggests exposure to antibiotics may also increase the risk of LBW. The mechanisms underlying this association are unknown, although epigenetic mechanisms are hypothesized. In this study, we evaluated the association between maternal antibiotic use and LBW and examined the potential role of altered DNA methylation that controls growth regulatory imprinted genes in these associations.

Methods:

Between 2009–2011, 397 pregnant women were enrolled and followed until delivery. Prenatal antibiotic use was ascertained through maternal self-report. Imprinted genes methylation levels were measured at differentially methylated regions (DMRs) using bisulfite pyrosequencing. Generalized linear models were used to examine associations among antibiotic use, birth weight and DMR methylation fractions.

Results:

After adjusting for infant gender, race/ethnicity, maternal body mass index, delivery route, gestational weight gain, gestational age at delivery, folic acid intake, physical activity, maternal smoking and parity, antibiotic use during pregnancy was associated with 138 g lower birth weight compared with non-antibiotic use (β-coefficient=−132.99, s.e.=50.70, P=0.008). These associations were strongest in newborns of women who reported antibiotic use other than penicillins (β-coefficient=−135.57, s.e.=57.38, P=0.02). Methylation at five DMRs, IGF2 (P=0.05), H19 (P=0.15), PLAGL1 (P=0.01), MEG3 (P=0.006) and PEG3 (P=0.08), was associated with maternal antibiotic use; among these, only methylation at the PLAGL1 DMR was also associated with birth weight.

Conclusion:

We report an inverse association between in utero exposure to antibiotics and lower infant birth weight and provide the first empirical evidence supporting imprinted gene plasticity in these associations.

Risk of oesophageal adenocarcinoma among individuals born preterm or small for gestational age

BACKGROUND

Gastroesophageal reflux is a main risk factor for oesophageal adenocarcinoma (EAC). Infants born preterm or small for gestational age (SGA) regurgitate more than infants born at term, and some data support the hypothesis of an association with oesophagitis, Barrett's oesophagus and EAC. This study aimed to assess the association between risk of EAC and preterm or SGA birth.

METHODS

In this population-based case-control study, all incident cases of EAC in Sweden between 1st January 1998 and 31st December 2004 with retrievable birth records were eligible as cases. We sampled three matched controls per case from the birth ledger at the same delivery ward as the respective case. Data on gestational age, birth weight and other perinatal exposures were extracted from the original birth records. For comparison, we collected perinatal data for cases of cardia adenocarcinoma and oesophageal squamous cell carcinoma and controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

RESULTS

The risk of EAC increased by 13% per week of shorter duration of gestation (OR 1.1, 95%CI 1.0-1.3), while SGA did not influence the risk. No effect of preterm birth or SGA was found on the risk of cardia adenocarcinoma or oesophageal squamous cell carcinoma.

CONCLUSION

Preterm birth, but not SGA, might lead to an increased risk of EAC as an adult.

Risk of esophagitis among individuals born preterm or small for gestational age

BACKGROUND & AIMS

The association between gastroesophageal reflux and esophageal adenocarcinoma is likely to be mediated by inflammation. Reflux is common in infancy; the esophageal mucosa of infants born preterm or small for gestational age (SGA) could be particularly vulnerable. We investigated the association between preterm or SGA birth and risk of esophagitis early in life.

METHODS

We analyzed data from the Swedish birth register and the Swedish patient register to identify birth characteristics of individuals with endoscopically verified esophagitis from 1973 to 2007 and to determine their outcomes (7358 cases). Five controls were selected randomly and matched with each case (N = 38,479). Multivariable conditional logistic regression models were used to provide odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for potential confounding.

RESULTS

The risk of esophagitis was increased among individuals born preterm (≤32 gestational weeks) (OR, 2.74; 95% CI, 2.15-3.49) or SGA (OR, 1.49; 95% CI, 1.32-1.68). When data were stratified by age at diagnosis and by sex, different risk patterns appeared. Among individuals diagnosed with esophagitis 9 years of age and younger, the OR for prematurity was 6.82 (95% CI, 4.65-10.03) and the OR for SGA at birth was 1.98 (95% CI, 1.55-2.52). Furthermore, the association with preterm birth was stronger among males (OR, 9.88; 95%, CI 5.93-16.45) than females (OR, 3.41; 95% CI, 1.81-6.41), whereas the association with SGA was stronger among females (OR, 2.50; 95% CI, 1.76-3.55) than males (OR, 1.64; 95% CI, 1.16-2.30). The risk of being diagnosed with esophagitis at age 20 or younger was not associated with preterm birth (OR, 1.02; 95% CI, 0.64-1.63), but was associated with being SGA at birth (OR, 1.31; 95% CI, 1.11-1.54).

CONCLUSIONS

Preterm birth is associated with esophagitis only during childhood, whereas SGA birth is associated with esophagitis during adolescence as well. The associations appear to differ between sexes.

Gastro-esophageal reflux disease in healthy older children and adolescents

Gastro-esophageal reflux disease (GERD) in otherwise healthy older children and adolescents is commonly encountered in pediatric clinics and poses a complex treatment problem involving changes of diets and lifestyle. After an initial history taking and a physical examination, typical symptoms of GERD in older children and adolescenct are initially treated with the trials of acid suppressants. With an increase of severe cases, more and more GERD children have been evaluated with endoscopy, which helps to delineate an erosive esophagitis from a non-erosive reflux disease as they are presumed to have different pathogenesis. For the pediatric patients without a significant underlying disease, a reflux esophagitis can be treated adequately with acid suppressants. Recently, the rapid increase of children who are taking anti-reflux medication has brought up a serious alarm among pediatricians. Some at risk pediatric patients with recurrent and/or chronic GERD have been linked to adulthood GERD. In this paper, pediatric GERD with and without erosive esophagitis was reviewed along with treatment options and issues specifically for the otherwise healthy older children and adolescents in the primary clinics or the secondary hospitals.

Clinical Perspectives on Esophageal Disorders in Infants

Esophageal pathologies are complex and lend themselves to multivariable analysis before a definitive diagnosis can be considered. It is imperative that the clinician establish a methodology for selecting the appropriate technological assessment within scientific testing parameters to establish optimal clinicopathological presentation and determine best practice for patient care.

Association of cord blood methylation fractions at imprinted insulin-like growth factor 2 (IGF2), plasma IGF2, and birth weight

Purpose

Altered methylation at Insulin-like Growth Factor 2 (IGF2) regulatory regions has previously been associated with obesity, and several malignancies including colon, esophageal, and prostate adenocarcinomas, presumably via changes in expression and/or loss of imprinting, but the functional significance of these DNA methylation marks have not been demonstrated in humans. We examined associations among DNA methylation at IGF2 differentially methylated regions (DMRs), circulating IGF2 protein concentrations in umbilical cord blood (UCB) and birth weight in newborns.

Methods

Questionnaire data were obtained from 300 pregnant women recruited between 2005 and 2009. UCB DNA methylation was measured by bisulfite pyrosequencing. UCB plasma concentrations of soluble IGF2 were measured by ELISA assays. Generalized linear regression models were used to examine the relationship between DMR methylation and IGF2 levels.

Results

Lower IGF2 DMR methylation was associated with elevated plasma IGF2 protein concentrations (β = −9.87, p < 0.01); an association that was stronger in infants born to obese women (pre-pregnancy BMI > 30 kg/m², β = −20.21, p < 0.0001). Elevated IGF2 concentrations were associated with higher birth weight (p < 0.0001) after adjusting for maternal race/ethnicity, pre-pregnancy BMI, cigarette smoking, gestational diabetes, and infant sex. These patterns of association were not apparent at the H19 DMR.

Conclusion

Our data suggest that variation in IGF2 DMR methylation is an important mechanism by which circulating IGF2 concentrations, a putative risk factor for obesity and cancers of the colon, esophagus, and prostate, are modulated; associations that may depend on pre-pregnancy obesity.

Gestational age at birth and risk of gastric acid-related disorders in young adulthood

PURPOSE

Preterm birth is associated with gastric acid-related disorders in infancy, but no investigators have examined this association beyond early childhood. We used antisecretory medication data to explore whether preterm birth is associated with gastric acid-related disorders in young adulthood.

METHODS

We conducted a national cohort study of 626,811 individuals born in Sweden in 1973 to 1979, followed up for antisecretory (proton pump inhibitor and H2-receptor antagonist) medication prescriptions from all outpatient and inpatient pharmacies nationwide from 2005 to 2009 (ages 25.5-37.0 years). We excluded individuals with congenital anomalies, and examined potential confounding by other comorbidities identified on the basis of oral anti-inflammatory or corticosteroid medication prescription.

RESULTS

Gestational age at birth was inversely associated with antisecretory medication prescription in young adulthood. Adjusted odds ratios for ≥1 antisecretory medication prescription/year were 3.38 (95% confidence interval [95% CI], 1.73-6.62) for individuals born at 22-27 weeks, 1.38 (95% CI, 1.19-1.60) for those born at 28-34 weeks, and 1.19 (95% CI, 1.06-1.32) for those born at 35-36 weeks, relative to those born full-term (37-42 weeks). Exclusion of individuals who were prescribed oral anti-inflammatory or corticosteroid medications (≥1/year) had little effect on these results.

CONCLUSIONS

These findings suggest that low gestational age at birth may be independently associated with an increased risk of gastric acid-related disorders in young adulthood.

Acid reducing agents to neonates - lack of evidence and guidelines

Objective

The aim of this retrospective study was to investigate the clinical practice, i.e. the frequency of use and the treatment strategies, for acid reducing drugs to neonates in a Swedish hospital.

Methods

Retrospective reviews of charts and interviews with nurses at the neonatal wards of Karolinska University Hospital were performed to identify difficulties that might occur with drug administration. All patients admitted over a 2-month period were included. Main outcome measure were the number of patients treated with acid reducing drugs and the dosages.

Results

Nine out of 215 patients (4.2%) received an acid reducing drug. Patients treated with acid reducing drugs had significantly lower birth weight, lower gestational age and longer duration of hospitalization. Eight of the patients were treated with omeprazole. One of these patients started treatment with omeprazole but continued later on with ranitidine. One patient was exclusively treated with ranitidine. The doses of omeprazole (intravenous or oral administration) were within the range 0.16–1.26 mg/kg/day.

Conclusions

A wide variation in treatment regimens of acid reducing drugs is given to newborn infants. The percentage of treated children was much lower than earlier reports from the US and UK. No conclusions can be drawn as to whether the doses and dosing intervals used give sufficient acid suppression, since the effect of the therapy was not recorded. The present study is only retrospective and data are not truly comparable with other studies. Further studies are therefore warranted to evaluate effective doses and pharmacokinetics of acid reducing drugs in newborn infants.

Review of the persistence of gastroesophageal reflux disease in children, adolescents and adults: does gastroesophageal reflux disease in adults sometimes begin in childhood?

OBJECTIVE

Understanding the natural history and outcomes of gastroesophageal reflux disease (GERD) in children could help to identify patients at risk of having GERD complications during adulthood. This review aimed to assess evidence of whether GERD in children or adolescents persists into adulthood.

MATERIAL AND METHODS

PubMed searches (1966-2010) identified longitudinal studies of GERD extending from childhood/infancy into adulthood, as well as longitudinal studies within pediatric age groups.

RESULTS

In one study, heartburn during childhood was more often recalled by adults with reflux symptoms than by those without (30% vs. 9%; p < 0.001), as was medication or surgery for GERD (both p < 0.01). Another study found that GERD symptoms were more common in adults diagnosed with reflux esophagitis during childhood/adolescence than in those who were not (46% vs. 30%). Regurgitation during infancy increased the risk of feeding problems after 1 year (odds ratio 4.2 (95% confidence interval: 1.4-12.0)) and of reflux symptoms at 9 years of age (relative risk 2.3 (95% confidence interval: 1.3-4.0)). In one study, abnormal esophageal histology persisted in infants after 12 months without reflux symptoms. A proportion (59-100%: three studies) of patients with reflux symptoms and/or reflux esophagitis during the pediatric years still required treatment after 1-8 years. In another study, however, just 7% of patients with healed reflux esophagitis relapsed after 9 months without treatment.

CONCLUSION

The limited available evidence suggests that some infants, children, and adolescents with GERD are more likely than those without GERD to have symptoms later in life.

Maternal nutrient restriction during late gestation and early postnatal growth in sheep differentially reset the control of energy metabolism in the gastric mucosa

Fetal growth restriction followed by accelerated postnatal growth contributes to impaired metabolic function in adulthood. The extent to which these outcomes may be mediated centrally within the hypothalamus, as opposed to in the periphery within the digestive tract, remains unknown. In a sheep model, we achieved intrauterine growth restriction experimentally by maternal nutrient restriction (R) that involved a 40% reduction in food intake through late gestation. R offspring were then either reared singly to accelerate postnatal growth (RA) or as twins and compared with controls also reared singly. From weaning, all offspring were maintained indoors until adulthood. A reduced litter size accelerated postnatal growth for only the first month of lactation. Independently from postnatal weight gain and later fat mass, R animals developed insulin resistance as adults. However, restricted accelerated offspring compared with both the control accelerated and restricted restricted offspring ate less and had higher fasting plasma leptin as adults, an adaptation which was accompanied by changes in energy sensing and cell proliferation within the abomasum. Additionally, although fetal restriction down-regulated gene expression of mammalian target of rapamycin and carnitine palmitoyltransferase 1-dependent pathways in the abomasum, RA offspring compensated for this by exhibiting greater activity of AMP-activated kinase-dependent pathways. This study demonstrates a role for perinatal nutrition in the peripheral control of food intake and in energy sensing in the gastric mucosal and emphasizes the importance of diet in early life in regulating energy metabolism during adulthood.

Big mother or small baby: which predicts hypertension?

According to the Barker hypothesis, intrauterine growth restriction and premature delivery adversely affect cardiovascular health in adult life. The association of childhood hypertension as a cardiovascular risk factor and birth weight has been understudied. In a prospective cohort study, the authors evaluated the effect of birth weight, gestational age, maternal prepregnancy body mass index (BMI), and child BMI z score at the time of enrollment on the systolic and diastolic blood pressure (BP) z score in 3024 (1373 women) consecutive outpatient clinic patients aged 2.05 to 18.58 years. The latest National Health and Nutrition Examination Survey (NHANES III) was used to calculate the age-dependent z scores. The median z scores of BMI (+0.48, range -6.96-6.64), systolic BP (+0.41, range -4.50-6.73), and diastolic BP (+0.34, range -3.15-+6.73) were all significantly greater than the NHANES III reference population. Systolic BP z score did not correlate with birth weight or gestational age, but did correlate with maternal prepregnancy BMI (r=.090, P<.0001) and BMI z score (r=.209, P<.0001). Diastolic BP z score positively correlated with birth weight (0.037, P=.044), gestational age (r=.052, P=.005), BMI z score(r=.106, P<.0001), and maternal prepregnancy BMI (r=.062, P=.0007). In contrast to what would be expected from the Barker hypothesis, the authors found no negative correlation between BP z score and birth weight or gestational age. This study suggests that a high BMI, a big mom, and a high birth weight are more important risk factors for hypertension during childhood than low birth weight or gestational age.

Early life nutrition and metabolic programming

Research investigating the early programming of adult metabolic disease has in recent years provided much mechanistic insight into how the early environment impacts on long-term health. It includes studies addressing the roles of intrauterine nutrient availability, which is determined by maternal nutrition, maternal exposure to oxygen, toxic events, and infection; the placental interface; and also the early postnatal environment. This review will explore the epidemiological evidence for programming of metabolic disease and provide an overview of the various studies using animals to model metabolic phenotypic outcome. It will also discuss evidence for the proposed molecular mechanisms and the potential for intervention.

IGF2R polymorphisms and risk of esophageal and gastric adenocarcinomas

The mannose-6-phosphate/insulin-like growth factor 2 receptor (M6P/IGF2R) encodes a protein that plays a critical role in tumor suppression, in part by modulating bioavailability of a potent mitogen, insulin-like growth factor-2 (IGF2). We tested the hypothesis that the common nonsynonymous genetic variants in M6P/IGF2R c.901C > G (Leu > Val) in exon 6 and c.5002G > A (Gly > Arg) in exon 34 are associated with risk of esophageal and gastric cancers. Study participants in this population-based study comprise 197 controls and 182 cases, including 105 with esophageal-gastric cardia adenocarcinoma (EGA), 57 with noncardia gastric adenocarcinoma and 20 with esophageal squamous (ES) cell carcinoma. Among white males, odds ratios (ORs) were elevated in relation to carrying at least 1 c.901C > G allele for EGA [OR = 1.9; 95% confidence intervals (CIs) = 1.0-3.6] and noncardia gastric cancer (OR = 2.5; 95% CI = 1.2-5.5), but not ES. Exploratory subgroup analyses suggested that associations between EGA and this variant were stronger among irregular or nonusers of nonsteroidal anti-inflammatory drugs (NSAIDs) (OR = 2.3; 95% CI = 1.2-4.2) and cigarette smokers (OR = 2.1; 95% CI = 1.0-4.2). An association between carrying the c.5002G > A genotype and EGA was not evident. These findings suggest that nonsynonymous polymorphisms in M6P/IGF2R may contribute to the risks of EGA and noncardia adenocarcinomas. Larger studies are required to confirm these findings.

Pediatric gastroesophageal reflux clinical practice guidelines: joint recommendations of the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) and the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN)

OBJECTIVE

To develop a North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) and European Society for Pediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) international consensus on the diagnosis and management of gastroesophageal reflux and gastroesophageal reflux disease in the pediatric population.

METHODS

An international panel of 9 pediatric gastroenterologists and 2 epidemiologists were selected by both societies, which developed these guidelines based on the Delphi principle. Statements were based on systematic literature searches using the best-available evidence from PubMed, Cumulative Index to Nursing and Allied Health Literature, and bibliographies. The committee convened in face-to-face meetings 3 times. Consensus was achieved for all recommendations through nominal group technique, a structured, quantitative method. Articles were evaluated using the Oxford Centre for Evidence-based Medicine Levels of Evidence. Using the Oxford Grades of Recommendation, the quality of evidence of each of the recommendations made by the committee was determined and is summarized in appendices.

RESULTS

More than 600 articles were reviewed for this work. The document provides evidence-based guidelines for the diagnosis and management of gastroesophageal reflux and gastroesophageal reflux disease in the pediatric population.

CONCLUSIONS

This document is intended to be used in daily practice for the development of future clinical practice guidelines and as a basis for clinical trials.

The Swedish personal identity number: possibilities and pitfalls in healthcare and medical research

Swedish health care and national health registers are dependent on the presence of a unique identifier. This paper describes the Swedish personal identity number (PIN) and explores ethical issues of its use in medical research. A ten-digit-PIN is maintained by the National Tax Board for all individuals that have resided in Sweden since 1947. Until January 2008, an estimated 75,638 individuals have changed PIN. The most common reasons for change of PIN are incorrect recording of date of birth or sex among immigrants or newborns. Although uncommon, change of sex always leads to change of PIN since the PIN is sex-specific. The most common reasons for re-use of PIN (n = 15,887), is when immigrants are assigned a PIN that has previously been assigned to someone else. This is sometimes necessary since there is a shortage of certain PIN combinations referring to dates of birth in the 1950s and 1960s. Several ethical issues can be raised pro and con the use of PIN in medical research. The Swedish PIN is a useful tool for linkages between medical registers and allows for virtually 100% coverage of the Swedish health care system. We suggest that matching of registers through PIN and matching of national health registers without the explicit approval of the individual patient is to the benefit for both the individual patient and for society.

Gastrointestinal maturation and implications for infant feeding

The level of gastrointestinal (GI) maturity of an individual infant is a major determinant of whether the infant will be able to meet nutritional needs by sole use of the GI tract or if parenteral means will be necessary. The GI tract is not only an organ for digestion and absorption of nutrients; it also performs major endocrine, neural and immunologic functions. In this review, anatomic, functional and biochemical development will be described and related to means by which enteral nutrition can be used in the prematurely born infant to optimize health and prevent disease.

Knowledge, attitudes and practice styles of North American pediatricians regarding gastroesophageal reflux disease

BACKGROUND

The North American Society for Pediatric Gastroenterology, Hepatology and Nutrition launched a provider and public education campaign in 2002 to raise awareness of gastroesophageal reflux disease (GERD). To determine the effectiveness of campaign messages, we conducted a knowledge, attitudes, and practice styles (KAPS) survey of pediatric providers. Understanding the spectrum of management styles of GERD in children is critical to achieve better health outcomes and reduce health care costs.

MATERIALS AND METHODS

The KAPS questionnaire was administered to 6000 randomly selected members of the American Academy of Pediatrics.

RESULTS

A total of 1245 members responded; 82% worked in a primary care setting and 18% in subspecialty practices. Overall, 66% of the members order diagnostic testing in routine practice, 54% start testing for GERD in neonates, and 38% start testing after 1 month of age. The most common tests ordered were barium esophagram (45%) and esophageal pH monitoring (37%). GERD treatment with acid suppression before ordering diagnostic testing was a choice of 82% of the respondents. However, 19% believed acid suppression was best achieved by H2 blockers. If acid suppression was indicated, then only 36% followed guideline recommendations for therapy duration and 52% followed guideline recommendations for dosing. Antireflux surgery was recommended only as a last resort by 92%. Overall, 69% of providers believed the amount of GERD-related information available was not enough. Respondents who were not aware of available GERD practice guidelines ranged from 74% to 92%.

CONCLUSIONS

Pediatric providers appear to frequently order diagnostic testing and treatment for GERD, yet knowledge about evidence-based GERD management among this random sample appeared limited. Moreover, a significant number of providers were not aware of different guideline publications.

Maternal nutrition, low nephron number, and hypertension in later life: pathways of nutritional programming

A large body of epidemiologic literature supports an inverse relation between birth weight and both systolic blood pressure and prevalence of hypertension, but mechanisms through which lower birth weight increases risk for hypertension are not established. This article advances the view that 1) permanently reduced nephron number is essential but not alone sufficient to mediate nutritionally induced hypertension; and 2) fetally programmed propensity for increased appetite and accelerated postnatal growth, thus generating inappropriately increased body mass, is a necessary "second hit" to actualize hypertension vulnerability. Based on decades of nephrologic research, this increased ratio of body mass (excretory load) to nephron number (excretory capacity) induces intrarenal compensations (tubular and glomerular hypertrophy with single-nephron hyperfiltration and intrarenal renin-angiotensin II activation), which maintain normal glomerular filtration rate at the expense of systemic and glomerular hypertension and at the risk of progressive renal disease. The vigor of the intrarenal compensatory responses is markedly greater in the immature than in the mature kidney, potentially explaining the greater risk of nephron deficits being present early in life as compared with the minimal risk in adult kidney donors. Effective interventions have not yet been defined. Suboptimal maternal nutrition, pervasive in both developed and developing countries, offers a window of opportunity to enhance the cardiovascular and renal health of future generations.

Second malignancies among survivors of germ-cell testicular cancer: a pooled analysis between 13 cancer registries

We investigated the risk of second malignancies among 29,511 survivors of germ-cell testicular cancer recorded in 13 cancer registries. Standardized incidence ratios (SIRs) were estimated comparing the observed numbers of second malignancies with the expected numbers obtained from sex-, age-, period- and population-specific incidence rates. Seminomas and nonseminomas, the 2 main histological groups of testicular cancer, were analyzed separately. During a median follow-up period of 8.3 years (0-35 years), we observed 1,811 second tumors, with a corresponding SIR of 1.65 (95% confidence interval (CI): 1.57-1.73). Statistically significant increased risks were found for fifteen cancer types, including SIRs of 2.0 or higher for cancers of the stomach, gallbladder and bile ducts, pancreas, bladder, kidney, thyroid, and for soft-tissue sarcoma, nonmelanoma skin cancer and myeloid leukemia. The SIR for myeloid leukemia was 2.39 (95% CI: 1.41-3.77) after seminomas, and 6.77 (95% CI: 4.14-10.5) after nonseminomas. It increased to 37.9 (95% CI: 18.9-67.8; based on 11 observed cases of leukemia) among nonseminoma patients diagnosed since 1990. SIRs for most solid cancers increased with follow-up duration, whereas they did not change with year of testicular cancer diagnosis. Among subjects diagnosed before 1980, 20 year survivors of seminoma had a cumulative risk of solid cancer of 9.6% (95% CI: 8.7-10.5%) vs. 6.5% expected, whereas 20 years survivors of nonseminoma had a risk of 5.0% (95% CI: 4.2-6.0%) vs. 3.1% expected. In conclusion, survivors of testicular cancers have an increased risk of several second primaries, where the effect of the treatment seems to play a major role.

Upstream effect of esophageal distention: effect on airway

The pharyngoesophageal segment of the foregut has an important function in steering clear of luminal contents from the airway, across the age spectrum from a premature neonate to an aging adult. This complex neuromuscular interaction between the esophagus and the airway is maintained by a variety of mechanisms mediated by the parasympathetic and sympathetic afferent and efferent outflows involving the myenteric plexus, glossopharyngeal and vagus cranial nerves, phrenic nerve, and brainstem nuclei. The esophageal provocation during gastroesophageal reflux events results in esophageal distention, followed by responses in the esophagus, the airway, or both. Studies involving esophageal provocation in human adults and animal models are beginning to illuminate the pathogenetic mechanisms associated with aerodigestive tract disease. However, studies pertinent to this topic in infants or children have been lacking. In this paper, we review recent advances concerning the motor responses of the esophagus and the airway ensuing upon esophageal distention. Recent advances in methods to evaluate aerodigestive responses in infants that have been validated are discussed.

Perinatal Risk Factors for Cancer of the Esophagus and Gastric Cardia: A Nested Case-Control Study

BACKGROUND

We have previously hypothesized that preterm birth or impaired fetal growth may cause esophageal adenocarcinomas through gastroesophageal reflux early in life. In this study, we aimed to test if there is an association between gestational duration and birth weight on the one hand, and risk of esophageal and cardia adenocarcinoma on the other.

METHODS

We conducted a nested case-control study of 67 cases of esophageal adenocarcinoma and 93 cases of cardia adenocarcinoma, whereas 50 cases of squamous cell carcinoma were studied for comparison. Birth records of cases were traced. Three matched controls per case were randomly selected. Perinatal data were extracted from birth records.

RESULTS

Long gestational duration was associated with a decreased risk of cardia adenocarcinoma (P(trend) = 0.001) and a nonsignificant decreased risk of esophageal adenocarcinoma (P = 0.07), whereas no such association was found for esophageal squamous cell carcinoma (P = 0.96). Birth weight was not associated with risk of any of the studied cancers. Compared with lower maternal age (</=24 years) at giving birth, maternal age of 25 to 29 years were associated with a decreased risk of esophageal adenocarcinoma and squamous cell carcinoma (odds ratio, 0.4; 95% confidence interval, 0.2-0.9 and odds ratio, 0.3; 95% confidence interval, 0.1-0.8, respectively).

CONCLUSIONS

Numerical constraints hamper inference, but our results are somewhat consistent with the idea that future risk of esophageal and cardia cancer may in part be determined already perinatally or in infancy and give some limited support to the hypothesis that timing of birth influences risk.

Gastrointestinal maturation and feeding

The intestine serves not only as a digestive absorptive organ, it is also one of the largest immune organs of the body, has a huge endocrine and exocrine role, and also encompasses neural tissue equivalent to that of the entire spinal cord. The microbial microenvironment also plays a critical role in development. This brief overview of developmental aspects of these intestinal functions will be related to clinical problems in the neonatal period and subsequent health.

Is gastroesophageal reflux disease really a life-long disease: do babies who regurgitate grow up to be adults with GERD complications?

There are a number of chronic digestive diseases in adults which have symptom and/or disease onset in childhood. Examples of childhood-onset chronic diseases include Helicobacter pylori-associated gastroduodenal disease and gastroesophageal reflux disease (GERD). Unfortunately, there is a paucity of well-designed longitudinal studies that characterize the natural history of each of these conditions and more importantly identify individuals (i.e., children) who are at risk for serious, long-term adult sequelae. Gastroesophageal reflux (GER), the physiological condition, and GERD, the disease, occur frequently during the first 2 yr of life. However, commonly held "dogma" by pediatricians is the belief that the majority of these children "grew out of their GER or GERD symptoms." On the contrary, recent evidence suggests that GERD in some subjects is a chronic, potentially life-long condition that begins in childhood, and in those in whom disease onset is early, there may be a higher risk for long-term severe disease sequelae. The article by Orenstein et al., although small in cohort size (N = 19), is the first systematic, longitudinal prospective study that employs both a validated GERD symptom assessment instrument and a histological characterization of esophageal inflammation via mucosal biopsies of infants during the first year of life. The infants, part of a larger therapeutic trial, were originally referred to the investigators for GERD evaluation, failed a 2-wk lifestyle modification trial, and were randomized to placebo or intervention (acid suppression and prokinetic therapy). This placebo cohort was evaluated in follow-up via assessment of symptoms using a validated Infant-Gastroesophageal-Reflux-Questionnaire (I-GERQ) and esophageal suction biopsy; morphometric characterization of mucosal histology and symptom scores were performed at 2, 4, 6, and 12 months. At the 12-month endpoint, 10 of 19 completed the study without rescue medication and overall symptom scores improved in all 10 completers. However, none of the 10 completers had normalization of biopsy assessments, i.e., basal cell layer <25% and papillary height <53% of epithelial thickness. The authors concluded that although symptoms improved in more than half of infants with reflux esophagitis followed longitudinally, esophageal mucosal histology remained abnormal at the 1-yr evaluation in the absence of pharmacotherapy. The lack of concordant improvement of the esophageal histology should raise concern regarding sub-clinical persistence of ongoing esophageal insult, which might in the long-term, predispose the individual to GERD-related complications, such as strictures, Barrett's esophagus, and/or esophageal adenocarcinoma. In this editorial, the implications of GERD being a life-long disease based on the findings described by Orenstein et al. are discussed. In addition, a description of areas where further research is critically needed is provided namely: (1) population-based, epidemiological studies of GERD with appropriate case and control definitions, (2) characterization of genetically "at-risk" individuals (i.e., with childhood-onset GERD) for severe GERD sequelae (e.g., Barrett's esophagus, esophageal adenocarcinoma), or potentially, (3) longitudinal, family cohort natural history studies with index pediatric GERD cases.