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Background: Non-communicable diseases (NCDs) are a global health issue, posing a substantial burden on the individual, community, and public health. The risk of developing NCDs is influenced by a complex interplay between genetic, epigenetic, and environmental factors.

Methods: The NorthPop Birth Cohort Study (NorthPop) constitutes an infrastructure enabling cutting-edge research on the foundational pathways to NCDs in childhood, including allergic diseases and asthma, overweight/obesity, cognitive and neurodevelopmental dysfunction, gastrointestinal disorders, and caries. NorthPop aims at recruiting 10,000 families. Pregnant women and their partners residing in Västerbotten County, Sweden are eligible. Recruitment started in 2016 and is anticipated to end in 2025. Extensive data on parental, fetal and child health outcomes, lifestyle, diet, and environmental exposures are prospectively collected using web-based questionnaires in pregnancy and childhood until the children turn 7 years old. Urine samples are collected from the pregnant woman at gestational age 14–24 weeks. Blood samples are collected at gestational age 28 weeks. Placenta and cord blood are collected at birth. A breast milk sample is collected 1 month postpartum. Blood samples from the children are collected at 18 months and 7 years of age. Oral swabs and fecal samples are collected from the children within 48 h of birth, at 1, 9 and 18 months, 3 and 7 years of age. At age 7 years, children are invited to a follow-up visit, including measurements of weight, height, blood pressure, pulse, hand grip strength, working memory, skin prick test and saliva sampling. Additional measurements, such as sleep–wake and light exposure, and additional biological samples are collected in sub-cohorts. Permission for linkage to medical records and national registers e.g., the Swedish Pregnancy Register, the National Patient Register, the Longitudinal Integration Database for Health insurance and Labor market studies and the Swedish Prescribed Drug Register has been granted.

Discussion: Our multidisciplinary approach allows us to study how early life exposures, as well as parental health and lifestyle, influence future health in the offspring. Our results are anticipated to contribute to the understanding of disease risk and may inform future strategies aimed at risk reduction, highly significant for public health.

Trial registration: Retrospectively registered at Researchweb 11 November 2024 (project number 279272).

Background: Proteins and lipids of milk fat globule membrane (MFGM) and probiotics are immunomodulatory. We hypothesized that Lactobacillus paracasei ssp. paracasei strain F19 (F19) would augment vaccine antibody and T helper 1 type immune responses whereas MFGM would produce an immune response closer to that of breastfed (BF) infants.

Objective: To compare the effects of supplementing formula with F19 or bovine MFGM on serum cytokine and vaccine responses of formula-fed (FF) and BF infants.

Design: FF infants were randomized to formula with F19 (n = 195) or MFGM (n = 192), or standard formula (SF) (n = 194) from age 21±7 days until 4 months. A BF group served as reference (n = 208). We analyzed seven cytokines (n = 398) in serum at age 4 months using magnetic bead-based multiplex technology. Using ELISA, we analyzed anti-diphtheria IgG (n = 258) and anti-poliovirus IgG (n = 309) concentrations in serum before and after the second and third immunization, respectively.

Results: Compared with SF, the F19 group had greater IL-2 and lower IFN-γ concentrations (p<0.05, average effect size 0.14 and 0.39). Compared with BF, the F19 group had greater IL-2, IL-4 and IL-17A concentrations (p<0.05, average effect size 0.42, 0.34 and 0.26, respectively). The MFGM group had lower IL-2 and IL-17A concentrations compared with SF (p<0.05, average effect size 0.34 and 0.31). Cytokine concentrations were comparable among the MFGM and BF groups. Vaccine responses were comparable among the formula groups.

Conclusions: Contrary to previous studies F19 increased IL-2 and lowered IFN-γ production, suggesting that the response to probiotics differs across populations. The cytokine profile of the MFGM group approached that of BF infants, and may be associated with the previous finding that infectious outcomes for the MFGM group in this cohort were closer to those of BF infants, as opposed to the SF group. These immunomodulatory effects support future clinical evaluation of infant formula with F19 or MFGM.

BACKGROUND: Preterm infants are at risk of iron deficiency (ID). Hepcidin has been suggested as a good additional indicator of ID in preterm infants, next to ferritin.

METHODS: In a prospective observational study, we analyzed serum hepcidin in 111 infants born after 32+0 to 36+6 wk gestational age during the first 4 mo of life.

RESULTS: Hepcidin concentrations decreased during the first 4 mo of life, and concentrations were lower in infants with ID compared to those without ID. Infants who developed ID at the age of 4 mo had already significantly lower levels of hepcidin at 1.5 mo of age, while ferritin was already significantly lower at the age of 1 wk.

CONCLUSION: Hepcidin concentrations of late preterm infants decrease during the first 4 mo of life. This decrease, which parallels a decrease of ferritin concentration, we interpret as a physiological response, aiming to increase iron availability. Hepcidin concentrations are lower in infants with ID compared with those without ID, with a notable change already observed at 1.5 mo of age. Hepcidin can be used as an early marker of ID, although an additive value of hepcidin over ferritin in the diagnosis of ID is not present.

OBJECTIVES: To evaluate any potential correlation between anti-tissue transglutaminase antibodies of type immunoglobulin A (tTG-IgA) and the degree of gluten induced enteropathy in children participating in a screening study for celiac disease (CD) and to assess to what extent the revised ESPGHAN (European Society for Paediatric Gastroenterology, Hepatology and Nutrition) guidelines cover this group of patients.

METHODS: This is a sub-study of a cross-sectional CD screening study, ETICS (Exploring the Iceberg of Celiacs in Sweden), a two-phased study performed during 2005-2006 and 2009-2010. The 13,279 participating children had a blood test obtained and those with positive tTG-IgA were recommended a small intestinal biopsy. The tTG-IgA levels at the time of biopsy were compared with the assessment of the biopsy.

RESULTS: There were 267 children included, of whom 230 were diagnosed with CD. Out of all children, 67 children had low tTG-IgA levels (<5 U/mL), whereof 55% had Marsh 3 lesions. All children with tTG-IgA levels exceeding 10 times the upper limit of normal values of 5 U/mL, i.e. 50 U/mL, were diagnosed with CD. Lowering the cut-off to 3 U/mL, all but one child with 30 U/mL got CD diagnosis.

CONCLUSION: By adapting the revised ESPGHAN criteria, biopsies could have been omitted in a fourth of all cases. Our results indicate, that the criteria might be useful even on screened children. Further studies are needed to confirm whether the 2012 ESPGHAN guidelines should be revised to also apply to the populations being screened.

OBJECTIVES: To evaluate the gluten-free diet (GFD) adherenceafter one year of follow-up in children with screening-detected celiac disease (CD) in a general population. METHODS: A total of 18,325 12 year olds were invited to participate in apopulation-based CD screening (ETICS- Exploring the Iceberg of Celiacs in Sweden), of whom 13,279 participated. In 240 children, CD was detected through elevated anti-tissue transglutaminase antibodies 2 (TG2-IgA) and verified by a small-intestinal biopsy. This sub-study included the 210 children with TG2-IgAevaluated both at the initialbiopsy occasion and at the one-year follow-up. GFD adherence was evaluated by a combination of TG2-IgA measurements and self-reported adherence (n = 193). RESULTS: After one year, 83% (179/210) had normalizedTG2-IgA levels (<5U/mL). Among those who had >50 U/mL at diagnosis,25% (16/63) still had elevated TG2-IgA but for the majority their initial values were more than halved. Most reported a high level ofGFD adherence ('always' 75%(158/193) and 'often' 14%(30/193)), and 75% (145/193) reported always adhereingcombined with normalized TG2-IgA. Although reporting that they were always adherent, 13 (6.7%) had not yet normalized their TG2-IgA levels completely, however, a majority of these initially had the highestTG2-IgA levels. CONCLUSIONS: GFD adherence is high in adolescents with CD detected by screening of the general population of Swedish 12yearolds. Almost all had normalized serology and reported GFD adherenceat the one-year follow-up. However, a few adolescents whoreported GFD adherence still had elevated TG2-IgA levelssuggesting more severe disease and/or non-adherence.

BACKGROUND: The diagnostic use of hepcidin is limited by the absence of standardization and lack of age-specific reference ranges in children in particular. The aim of this study was to determine reference ranges of serum hepcidin in healthy children aged 0.5-3 y using mass spectometry (MS) and a commercial immunochemical (IC) assay, and to investigate its association with other indicators of iron status and inflammation. METHODS: We included 400 healthy children aged 0.5-3 y. We constructed reference ranges for MS-hepcidin and IC-hepcidin concentrations using the median, P2.5, and P97.5 in a normative population of 219 children with no anemia, no infection and/or inflammation, and no iron deficiency. RESULTS: Median concentrations (P2.5-P97.5) of MS-hepcidin and IC-hepcidin were 3.6 nmol/l (0.6-13.9 nmol/l) and 7.9 nmol/l (1.9-28.6 nmol/l), respectively. We found a good correlation between both methods. However, MS-hepcidin was consistently lower than IC-hepcidin. Hepcidin correlated with ferritin and C-reactive protein. CONCLUSION: We provide reference ranges for hepcidin for an MS and commercial IC method. Absolute values between assays differed significantly, but hepcidin concentrations obtained by MS and IC methods correlate with each other, and both correlate with ferritin and CRP.

Objectives: The aim of this study was to evaluate hypothetical screening strategies in a Swedish celiac disease (CD) mass screening.

Methods: Of 10,041 Swedish sixth graders born in 1993 invited to a population-based CD mass screening, 7208 participated. Anti-tissue transglutaminase (tTG) immunoglobulin (Ig) A were analyzed in all children and total serum IgA (s-IgA) in 7161 children. Additional analyses of tTG-IgG, endomysial antibodies (EMA) IgA and IgG, and human leukocyte antigen (HLA) alleles were performed according to a standardized protocol. Children with elevated levels of serological markers were recommended to undergo a small intestinal biopsy to verify diagnosis, and 153 children with CD were thus identified. Sensitivity, specificity, positive predictive values (PPVs) and negative predictive values (NPVs) were calculated and receiver operating characteristic curves were plotted.

Results: By lowering the cutoff for tTG-IgA, 17 additional cases of CD were identified at the cost of 32 biopsies. All children with tTG-IgA >50 U/mL (10 times the recommended upper limit of normal) had gluten enteropathy. Area under the receiver operating characteristic curve for tTG-IgA was 0.988. All cases carried HLA-DQ2 or HLA-DQ8, as did 53% of the controls. For different hypothetical screening strategies, sensitivity, specificity, PPV, and NPV ranged between 87.6% and 100%, 99.5% and 99.9%, 79.7% and 89.7%, and 99.7% and 100%, respectively. Efforts to increase sensitivity by lowering tTG-IgA cutoff would result in increased number of small intestinal biopsies and lower PPV. Sequential testing for both EMA and HLA-DQ genotyping would reduce the number of negative small intestinal biopsies.

Conclusions: tTG-IgA is a robust marker when used in CD mass screening and its performance can be enhanced by sequential testing for EMA or HLA-DQ genotyping.

Objetive: Sweden experienced a marked epidemic of celiac disease between 1984 and 1996 in children younger than 2 years of age, partly explained by changes in infant feeding. The objective of this study was to determine the prevalence of celiac disease in 12-year-olds born during the epidemic (1993), including both symptomatic and screening detected cases.

Patients and methods: All sixth-grade children in participating schools were invited (n = 10,041). Symptomatic and, therefore, previously diagnosed celiac disease cases were ascertained through the National Swedish Childhood Celiac Disease Register and/or medical records. All serum samples were analyzed for antihuman tissue transglutaminase (tTG)-IgA (Celikey), and serum-IgA, and some for tTG-IgG and endomysial antibodies. A small intestinal biopsy was recommended for all children with suspected undiagnosed celiac disease.

Results: Participation was accepted by 7567 families (75%). Previously diagnosed celiac disease was found in 67 children; 8.9/1000 (95% confidence interval [CI] 6.7-11). In another 192 children, a small intestinal biopsy was recommended and was performed in 180. Celiac disease was verified in 145 children, 20/1000 (95% CI 17-23). The total prevalence was 29/1000 (95% CI 25-33).

Conclusions: The celiac disease prevalence of 29/1000 (3%)-with two thirds of cases undiagnosed before screening-is 3-fold higher than the usually suggested prevalence of 1%. When these 12-year-olds were infants, the prevailing feeding practice was to introduce gluten abruptly, often without ongoing breast-feeding, which might have contributed to this unexpectedly high prevalence.