Infant microbes and metabolites point to childhood neurodevelopmental disorders.

This study has followed a birth cohort for over 20 years to find factors associated with neurodevelopmental disorder (ND) diagnosis. Detailed, early-life longitudinal questionnaires captured infection and antibiotic events, stress, prenatal factors, family history, and more. Biomarkers including cord serum metabolome and lipidome, human leukocyte antigen (HLA) genotype, infant microbiota, and stool metabolome were assessed. Among the 16,440 Swedish children followed across time, 1,197 developed an ND. Significant associations emerged for future ND diagnosis in general and for specific ND subtypes, spanning intellectual disability, speech disorder, attention-deficit/hyperactivity disorder, and autism. This investigation revealed microbiome connections to future diagnosis as well as early emerging mood and gastrointestinal problems. The findings suggest links to immunodysregulation and metabolism, compounded by stress, early-life infection, and antibiotics. The convergence of infant biomarkers and risk factors in this prospective, longitudinal study on a large-scale population establishes a foundation for early-life prediction and intervention in neurodevelopment.

Early-life diet and risk of inflammatory bowel disease: a pooled study in two Scandinavian birth cohorts.

OBJECTIVE: We assessed whether early-life diet quality and food intake frequencies were associated with subsequent IBD. DESIGN: Prospectively recorded 1-year and 3-year questionnaires in children from the All Babies in Southeast Sweden and The Norwegian Mother, Father and Child Cohort Study were used to assess diet quality using a Healthy Eating Index and intake frequency of food groups. IBD was defined as >2 diagnoses in national patient registers. Cox regression yielded HRs adjusted (aHRs) for child's sex, parental IBD, origin, education level and maternal comorbidities. Cohort-specific results were pooled using a random-effects model. RESULTS: During 1 304 433 person-years of follow-up, we followed 81 280 participants from birth through childhood and adolescence, whereof 307 were diagnosed with IBD. Compared with low diet quality, medium and high diet quality at 1 year of age were associated with a reduced risk of IBD (pooled aHR 0.75 (95% CI=0.58 to 0.98) and 0.75 (95% CI=0.56 to 1.00)). The pooled aHR per increase of category was 0.86 (0.74 to 0.99). Pooled aHR for children 1 year old with high versus low fish intake was 0.70 (95% CI=0.49 to 1.00) for IBD, and showed association with reduced risk of UC (pooled aHR=0.46; 95% CI=0.21, 0.99). Higher vegetable intake at 1 year was associated with a risk reduction in IBD. Intake of sugar-sweetened beverages was associated with an increased risk of IBD. Diet quality at 3 years was not associated with IBD. CONCLUSION: In this Scandinavian birth cohort, high diet quality and fish intake in early life were associated with a reduced risk of IBD.

Progression of type 1 diabetes is associated with high levels of soluble PD-1 in islet autoantibody-positive children.

AIMS/HYPOTHESIS: Type 1 diabetes is an autoimmune disorder that is characterised by destruction of pancreatic beta cells by autoreactive T lymphocytes. Although islet autoantibodies (AAb) are an indicator of disease progression, specific immune biomarkers that can be used as target molecules to halt development of type 1 diabetes have not been discovered. Soluble immune checkpoint molecules (sICM) play a pivotal role in counteracting excessive lymphocyte responses, but their role in type 1 diabetes is unexplored. In this longitudinal study, we measured sICM levels in AAb-positive (AAb+) children to identify molecules related to type 1 diabetes progression. METHODS: We measured the levels of 14 sICM in the sera of AAb+ children (n=57) compared to those with recent-onset type 1 diabetes (n=79) and healthy children (n=44), obtained from two cohorts. AAb+ children were followed up and divided based on their progression to type 1 diabetes (AAbP) or not (AAbNP) (if they lost islet autoimmunity and did not develop disease in subsequent years). sICM were also measured in the sample taken at the visit closest to disease onset in AAbP children. RESULTS: We found that AAb+ children had a distinct sICM profile compared with healthy children and those with recent-onset type 1 diabetes. In addition, AAb+ children who progressed to type 1 diabetes (AAbP) had higher sICM concentrations than non-progressors (AAbNP). Further, sICM levels decreased in AAbP children close to disease onset. Application of Cox regression models highlighted that high concentrations of soluble programmed cell death protein 1 (sPD-1) are associated with type 1 diabetes progression (HR 1.71; 95% CI 1.16, 2.51; p=0.007). CONCLUSIONS/INTERPRETATION: This study reveals an sICM profile that is dysregulated during the preclinical stage of type 1 diabetes, and identifies sPD-1 as a pathophysiologically-relevant molecule that is associated with disease progression, offering a potential target for early interventions in autoimmune diabetes.

Assisting the implementation of screening for type 1 diabetes by using artificial intelligence on publicly available data.

The type 1 diabetes community is coalescing around the benefits and advantages of early screening for disease risk. To be accepted by healthcare providers, regulatory authorities and payers, screening programmes need to show that the testing variables allow accurate risk prediction and that individualised risk-informed monitoring plans are established, as well as operational feasibility, cost-effectiveness and acceptance at population level. Artificial intelligence (AI) has the potential to contribute to solving these issues, starting with the identification and stratification of at-risk individuals. ASSET (AI for Sustainable Prevention of Autoimmunity in the Society; www.asset.healthcare ) is a public/private consortium that was established to contribute to research around screening for type 1 diabetes and particularly to how AI can drive the implementation of a precision medicine approach to disease prevention. ASSET will additionally focus on issues pertaining to operational implementation of screening. The authors of this article, researchers and clinicians active in the field of type 1 diabetes, met in an open forum to independently debate key issues around screening for type 1 diabetes and to advise ASSET. The potential use of AI in the analysis of longitudinal data from observational cohort studies to inform the design of improved, more individualised screening programmes was also discussed. A key issue was whether AI would allow the research community and industry to capitalise on large publicly available data repositories to design screening programmes that allow the early detection of individuals at high risk and enable clinical evaluation of preventive therapies. Overall, AI has the potential to revolutionise type 1 diabetes screening, in particular to help identify individuals who are at increased risk of disease and aid in the design of appropriate follow-up plans. We hope that this initiative will stimulate further research on this very timely topic.

Breastfeeding Duration Is Not Associated With Offspring Inflammatory Bowel Disease Risk in Three Population-Based Birth Cohorts.

BACKGROUND & AIMS: Breastfeeding is critical for offspring health and development. Although many observational studies report a protective effect between breastfeeding and inflammatory bowel disease (IBD), the relationship is not well-understood. METHODS: We used prospectively collected data from 3 population-based birth cohorts (Danish National Birth Cohort, Norwegian Mother, Father, and Child Cohort, and All Babies in Southeast Sweden) and cross-linked national registers to ascertain the impact of breastfeeding duration on offspring IBD risk in each country, using adjusted Cox proportional regression analyses. We performed meta-analyses to determine pooled estimates. RESULTS: We included 148,737 offspring and 169,510 offspring in analyses of exclusive and any breastfeeding duration, respectively. During median follow-up of 16.3-22.3 years, between 1996 and 2021, 543 offspring were diagnosed with IBD. In each country, there was no association between exclusive breastfeeding duration and offspring IBD risk after adjusting for birth year (Denmark), offspring sex, parental IBD status, maternal education, smoking during pregnancy, age at delivery, mode of delivery, preterm birth, and small for gestational age. The pooled adjusted hazard ratio for IBD was 1.24 (95% confidence interval, 0.94-1.62; Q = 0.16, I2 = 0.0%) and 1.02 (95% confidence interval, 0.85-1.21; Q = 1.45, I 2= 0.0%) among offspring breastfed exclusively for ≥6 months and <4 months, respectively, compared with 4-5 months. Similarly, we found null associations in pooled analyses of any breastfeeding duration and IBD, subtypes Crohn's disease and ulcerative colitis, as well as in cohort-specific analyses. CONCLUSIONS: In prospectively collected data from 3 population-based birth cohorts, the duration of exclusive or any breastfeeding was not associated with offspring IBD risk.

Atopic Dermatitis in Early Childhood and Risk of Inflammatory Bowel Disease: A Scandinavian Birth Cohort Study.

OBJECTIVE: To examine the association between early-life atopic manifestations and later risk of inflammatory bowel disease (IBD), for which prospective data are scarce. STUDY DESIGN: The population-based All Babies in Southeast Sweden (ABIS) and Norwegian Mother, Father, and Child (MoBa) cohorts follow children from birth (ABIS 1997-1999; MoBa 2000-2009) to the end of 2021. Based on validated questionnaires, parents prospectively reported information on asthma, food-related allergic symptoms, atopic dermatitis, and allergic rhinitis by age 3. IBD was defined by ≥ 2 diagnostic records in the national health registries. Cox regression estimated hazard ratios adjusted (aHRs) for parental IBD, atopy, education level, smoking habits, and national origin. Cohort-specific estimates were pooled using a random-effects model. RESULTS: We compiled data on 83 311 children (ABIS, n = 9041; MoBa, n = 74 270). In over 1 174 756 person-years of follow-up, 301 participants were diagnosed with IBD. Children with atopic dermatitis at age 3 had an increased risk of IBD (pooled aHR = 1.46 [95% CI = 1.13-1.88]), Crohn's disease (pooled aHR = 1.53 [95%CI = 1.04-2.26]), and ulcerative colitis (pooled aHR = 1.78 [95%CI = 1.15-2.75]). Conversely, any atopic manifestation by age 3 was not associated with IBD (pooled aHR = 1.20 [95%CI = 0.95-1.52]), nor were analyses specifically focused on early-life food-related allergic symptoms, asthma, and allergic rhinitis. CONCLUSION: While atopic manifestations in early childhood were overall not associated with IBD, children with atopic dermatitis specifically were at increased risk of developing IBD, suggesting shared etiologic traits; these findings might be useful in identifying at-risk individuals for IBD.

HbA1c and the risk of developing peripheral neuropathy in childhood-onset type 1 diabetes: A follow-up study over 3 decades.

AIMS: We have evaluated long-term weighted mean HbA1c (wHbA1c), HbA1c variability, diabetes duration, and lipid profiles in relation to the development of diabetic peripheral neuropathy (DPN), nephropathy, and retinopathy in childhood-onset type 1 diabetes. MATERIALS AND METHODS: In a longitudinal cohort study, 49 patients (21 women) with childhood-onset type 1 diabetes were investigated with neurophysiological measurements, blood tests, and clinical examinations after a diabetes duration of 7.7 (±3.3) years (baseline) and followed with repeated examinations for 30.6 (±5.2) years. We calculated wHbA1c by integrating the area under all HbA1c values since the diabetes diagnosis. Lipid profiles were analysed in relation to the presence of DPN. Long-term fluctuations of HbA1c variability were computed as the standard deviation of all HbA1c measurements. Data regarding the presence of other diabetes complications were retrieved from medical records. RESULTS: In this follow-up study, 51% (25/49) of the patients fulfilled electrophysiological criteria for DPN. In nerve conduction studies, there was a deterioration in the amplitudes and conduction velocities for the median, peroneal, and sural nerves over time. Patients with DPN had a longer duration of diabetes, higher wHbA1c, and increased HbA1c variability. The lowest wHbA1c value associated with the development of DPN was 62 mmol/mol (7.8%). The presence of albuminuria and retinopathy was positively correlated with the presence of neuropathy. CONCLUSIONS: More than half of the patients had developed DPN after 30 years. None of the patients who developed DPN had a wHbA1c of less than 62 mmol/mol (7.8%).

Breastfeeding decreases the risk of developing psoriasis through to early adulthood.

BACKGROUND: Psoriasis is a genetically determined systemic skin disease, although environmental trigger factors are required for disease manifestation. Some of these triggers, such as stress, infections and drug exposure, have been identified. OBJECTIVES: To explore the role of early nutrition as a risk factor for the development of psoriasis. METHODS: Parents in the All Babies in Southeast Sweden (ABIS) prospective birth cohort (n = 16 415) answered questionnaires at birth and when their children were aged 1 and 3 years. A diagnosis of psoriasis was determined from the Swedish National Patient Register and National Drug Prescription Register. Statistical analyses were conducted using custom-written R scripts. RESULTS: Individuals breastfed for < 4 months and who received infant formula before 4 months of age had a higher risk of psoriasis [odds ratio (OR) 1.84 (P = 0.02) and OR 1.88 (P = 0.02), respectively]. At the 3-year follow-up, the increased consumption of fish, especially from the Baltic Sea, increased the risk of psoriasis (OR 9.61; P = 0.003). In addition, the risk of psoriasis increased following the consumption of a large volume of milk (OR 2.53; P = 0.04). CONCLUSIONS: Our study underscores, for the first time, the impact of very early nutrition on the manifestation of psoriasis through early adulthood. Exclusive breastfeeding for 4 months appears to be protective.

Impact of Environmental Exposures on Human Breast Milk Lipidome in Future Immune-Mediated Diseases.

The composition of human breast milk (HBM) exhibits significant variability both between individuals and within the same individual. While environmental factors are believed to play a role in this variation, their influence on breast milk composition remains inadequately understood. Herein, we investigate the impact of environmental factors on HBM lipid composition in a general population cohort. The study included mothers (All Babies In Southeast Sweden study) whose children later progressed to one or more immune-mediated diseases later in life: type 1 diabetes (n = 9), celiac disease (n = 24), juvenile idiopathic arthritis (n = 9), inflammatory bowel disease (n = 7), hypothyroidism (n = 6), and matched controls (n = 173). Lipidome of HBM was characterized by liquid chromatography combined with high-resolution mass spectrometry. We observed that maternal age, body mass index, diet, and exposure to perfluorinated alkyl substances (PFASs) had a marked impact on breast milk lipidome, with larger changes observed in the milk of those mothers whose children later developed autoimmune diseases. We also observed differences in breast milk lipid composition in those mothers whose offspring later developed autoimmune diseases. Our study suggests that breast milk lipid composition is modified by a complex interaction between genetic and environmental factors, and, importantly, this impact was significantly more pronounced in those mothers whose offspring later developed autoimmune/inflammatory diseases. Our findings also suggest that merely assessing PFAS concentration may not capture the full extent of the impact of chemical exposures; thus, the more comprehensive exposome approach is essential for accurately assessing the impact of PFAS exposure on HBM and, consequently, on the health outcomes of the offspring.

Determination of autoantibodies in type 2 diabetes: one simple way to improve classification.

This letter aims to increase interest in better classification of type 2 diabetes. This can be done in a simple and cheap way via determination of autoantibodies. Autoantibody analysis can be used to detect the 7-12% of people with diabetes that is phenotypic of type 2 diabetes but is, in fact, latent autoimmune diabetes in adults (LADA), which may be regarded as a variant of type 1 diabetes. This may help to explain why some individuals with type 2 diabetes do not go into remission after reducing their weight, while others do, and why remission sometimes ends earlier than expected. Improved classification of diabetes may play an important role in determining adequate therapy.

Infant gut microbiome composition correlated with type 1 diabetes acquisition in the general population: the ABIS study.

AIMS/HYPOTHESIS: While autoantibodies are traditional markers for type 1 diabetes development, we identified gut microbial biomarkers in 1-year-old infants associated with future type 1 diabetes up to 20 years before diagnosis. METHODS: Infants enrolled in the longitudinal general population cohort All Babies In Southeast Sweden (ABIS) provided a stool sample at a mean age of 12.5 months. Samples (future type 1 diabetes, n=16; healthy controls, n=268) were subjected to 16S ribosomal RNA (rRNA) sequencing and quantitative PCR. Microbial differences at the taxonomic and core microbiome levels were assessed. PICRUSt was used to predict functional content from the 16S rRNA amplicons. Sixteen infants, with a future diagnosis of type 1 diabetes at a mean age of 13.3±5.4 years, and one hundred iterations of 32 matched control infants, who remained healthy up to 20 years of age, were analysed. RESULTS: Parasutterella and Eubacterium were more abundant in healthy control infants, while Porphyromonas was differentially more abundant in infants with future type 1 diabetes diagnosis. Ruminococcus was a strong determinant in differentiating both control infants and those with future type 1 diabetes using random forest analysis and had differing trends of abundance when comparing control infants and those with future type 1 diabetes. Flavonifractor and UBA1819 were the strongest factors for differentiating control infants, showing higher abundance in control infants compared with those with future type 1 diabetes. Alternatively, Alistipes (more abundant in control infants) and Fusicatenibacter (mixed abundance patterns when comparing case and control infants) were the strongest factors for differentiating future type 1 diabetes. Predicted gene content regarding butyrate production and pyruvate fermentation was differentially observed to be higher in healthy control infants. CONCLUSIONS/INTERPRETATION: This investigation suggests that microbial biomarkers for type 1 diabetes may be present as early as 1 year of age, as reflected in the taxonomic and functional differences of the microbial communities. The possibility of preventing disease onset by altering or promoting a 'healthy' gut microbiome is appealing. DATA AVAILABILITY: The forward and reverse 16S raw sequencing data generated in this study are available through the NCBI Sequence Read Archive under BioProject PRJNA875929. Associated sample metadata used for statistical comparison are available in the source data file. R codes used for statistical comparisons and figure generation are available at: https://github.com/PMilletich/T1D_Pipeline .

Autoantibody and T cell responses to oxidative post-translationally modified insulin neoantigenic peptides in type 1 diabetes.

AIMS/HYPOTHESIS: Antibodies specific to oxidative post-translational modifications (oxPTM) of insulin (oxPTM-INS) are present in most individuals with type 1 diabetes, even before the clinical onset. However, the antigenic determinants of such response are still unknown. In this study, we investigated the antibody response to oxPTM-INS neoepitope peptides (oxPTM-INSPs) and evaluated their ability to stimulate humoral and T cell responses in type 1 diabetes. We also assessed the concordance between antibody and T cell responses to the oxPTM-INS neoantigenic peptides. METHODS: oxPTM-INS was generated by exposing insulin to various reactive oxidants. The insulin fragments resulting from oxPTM were fractionated by size-exclusion chromatography further to ELISA and LC-MS/MS analysis to identify the oxidised peptide neoepitopes. Immunogenic peptide candidates were produced and then modified in house or designed to incorporate in silico-oxidised amino acids during synthesis. Autoantibodies to the oxPTM-INSPs were tested by ELISA using sera from 63 participants with new-onset type 1 diabetes and 30 control participants. An additional 18 fresh blood samples from participants with recently diagnosed type 1 diabetes, five with established disease, and from 11 control participants were used to evaluate, in parallel, CD4+ and CD8+ T cell activation by oxPTM-INSPs. RESULTS: We observed antibody and T cell responses to three out of six LC-MS/MS-identified insulin peptide candidates: A:12-21 (SLYQLENYCN, native insulin peptide 3 [Nt-INSP-3]), B:11-30 (LVEALYLVCGERGFFYTPKT, Nt-INSP-4) and B:21-30 (ERGFFYTPKT, Nt-INSP-6). For Nt-INSP-4 and Nt-INSP-6, serum antibody binding was stronger in type 1 diabetes compared with healthy control participants (p≤0.02), with oxidised forms of ERGFFYTPKT, oxPTM-INSP-6 conferring the highest antibody binding (83% binders to peptide modified in house by hydroxyl radical [●OH] and >88% to in silico-oxidised peptide; p≤0.001 vs control participants). Nt-INSP-4 induced the strongest T cell stimulation in type 1 diabetes compared with control participants for both CD4+ (p<0.001) and CD8+ (p=0.049). CD4+ response to oxPTM-INSP-6 was also commoner in type 1 diabetes than in control participants (66.7% vs 27.3%; p=0.039). Among individuals with type 1 diabetes, the CD4+ response to oxPTM-INSP-6 was more frequent than to Nt-INSP-6 (66.7% vs 27.8%; p=0.045). Overall, 44.4% of patients showed a concordant autoimmune response to oxPTM-INSP involving simultaneously CD4+ and CD8+ T cells and autoantibodies. CONCLUSIONS/INTERPRETATION: Our findings support the concept that oxidative stress, and neoantigenic epitopes of insulin, may be involved in the immunopathogenesis of type 1 diabetes.

Estimated glucose disposal rate is associated with retinopathy and kidney disease in young people with type 1 diabetes: a nationwide observational study.

AIMS: The aim of this study was to investigate the association between estimated glucose disposal rate (eGDR), a proxy for insulin resistance, and retinopathy or kidney disease, i.e. micro-, or macroalbuminuria, in young individuals with type 1 diabetes (T1D). MATERIAL AND METHODS: Using data from the Swedish pediatric registry for diabetes (SweDiabKids) and the registry for adults (NDR), all individuals with T1D with a duration of diabetes of less than 10 years between 1998 and 2017 were included. We calculated the crude incidence rates with 95% confidence intervals (CIs) and used multivariable Cox regression to estimate crude and adjusted hazard ratios (HRs) for two cohorts: retinopathy cohort or kidney disease cohort, stratified by eGDR categories: < 4, 4 to 5.99, 6 to 7.99, and ≥ 8 mg/kg/min (reference). RESULTS: A total of 22 146 (10 289 retinopathy cohort, and 11 857 kidney disease cohort with an overlapping of 9575) children and adults with T1D (median age 21 years, female 42% and diabetes duration of 6 and 7 years, respectively for the cohorts) were studied. During a median follow-up of 4.8 years (IQR 2.6-7.7) there were 5040 (24.7%), 1909 (48.1%), 504 (52.3%) and 179 (57.6%) events for retinopathy in individuals with an eGDR ≥ 8, 7.99 to 6, 5.99 to 4, and < 4 mg/kg/min, respectively. Corresponding numbers for kidney disease was 1321 (6.5%), 526 (13.3%), 255 (26.8%) and 145 (46.6%). After multiple adjustments for different covariates, individuals with an eGDR 7.99 to 6, 5.99 to 4 and < 4 mg/kg/min, had an increased risk of retinopathy compared to those with an eGDR ≥ 8 mg/kg/min (adjusted HRs, 95% CIs) 1.29 (1.20 to 1.40); 1.50 (1.31 to 1.71) and 1.74 (1.41 to 2.14). Corresponding numbers for kidney disease was (adjusted HRs, 95% CIs) 1.30 (1.11 to 1.52); 1.58 (1.25 to 1.99) and 1.33 (0.95 to 1.86), respectively. CONCLUSIONS: eGDR, a proxy for insulin resistance, is associated with retinopathy and kidney disease in young adults with T1D. The risk of retinopathy increased with lower eGDR. The risk of kidney disease also increased with lower eGDR; however results show no association between the lowest eGDR and kidney disease. eGDR can be helpful to identify young T1D individuals at risk.

A 1-year pilot study of intralymphatic injections of GAD-alum in individuals with latent autoimmune diabetes in adults (LADA) with signs of high immunity: No safety concerns and resemblance to juvenile type 1 diabetes.

AIMS: To test, for the first time in latent autoimmune diabetes in adults (LADA), the effects of autoantigen-specific immunotherapy by intralymphatic administration of aluminium-formulated recombinant human glutamic acid decarboxylase 65 (GAD-alum); specifically, to test if this treatment is safe, to test whether it induces a strong immunological response akin to a similar protocol in type 1 diabetes and to look for associations with preserved beta-cell function. MATERIALS AND METHODS: Three GAD-alum injections, 4 µg each, were administered 1 month apart into an inguinal lymph node in 14 people with newly diagnosed LADA (age 30-62 years) presenting with high levels of antibodies against glutamic acid decarboxylase (GADA). Adverse effects, immunological variables and beta-cell function were monitored, with detailed measurements at 5 and 12 months from baseline. RESULTS: Clinical adverse effects were minor and transient and measured laboratory variables were unaffected. All participants completed the study. Treatment raised levels of GADA, elicited strong effects on reactivity of peripheral blood mononuclear cells to GAD and raised cytokine/chemokine levels. Beta-cell function appeared stable preferentially in the seven participants carrying human leukocyte antigen (HLA) haplotypes DR3DQ2, as assessed by C-peptide glucagon tests (P < 0.05 vs. seven non-carriers). CONCLUSION: Intralymphatic treatment with GAD-alum in LADA is without clinical or other safety concerns over a 12-month period. As in a similar protocol used in type 1 diabetes, treatment exerts a strong immunological impact and is compatible with protection of beta-cell function preferentially in HLA-DR3DQ2 LADA patients. These findings pave the way for a randomized controlled trial in this important subgroup of LADA patients.

Epidemiology, validation, and clinical characteristics of inflammatory bowel disease: the ABIS birth cohort study.

BACKGROUND: Birth cohort studies with linked register-based data on inflammatory bowel disease (IBD) provide opportunities to prospectively study early-life determinants of the disease. However, register-based data often lack information on clinical characteristics and rely on diagnostic algorithms. Within the All Babies in Southeast Sweden (ABIS) cohort, we examined the validity of a register-based definition of IBD, its incidence, and clinical and therapeutic characteristics at diagnosis. METHODS: We followed 16,223 children from birth (1997-1999) until the end of 2020 for the diagnosis of IBD as defined by a minimum of two diagnostic codes for IBD in the Swedish National Patient Register (NPR). We described the incidence and cumulative incidence of IBD. Through a medical record review of cases diagnosed by the end of 2017, we examined the positive predictive value (PPV) for IBD and described its clinical characteristics and treatment. RESULTS: By 2020, at an average age of 22.2 years, 113 participants (0.74%, 95% confidence interval [CI] = 0.61-0.89) had a register-based diagnosis of IBD, corresponding to an incidence of 31.3 per 100,000 person-years of follow-up; the incidence for Crohn's disease (CD) was 11.1 per 100,000 person-years and 15.8 for ulcerative colitis (UC). Of 77 participants with a register-based definition of IBD by the end of 2017, medical records were identified for 61 participants, of whom 57 had true IBD (PPV = 93%; 95%CI = 0.87-1.00). While oral 5-aminosalicylic acid treatment was equally common in newly diagnosed CD and UC patients, biologics were more often used for newly diagnosed CD. The median faecal calprotectin levels were 1206 mg/kg at diagnosis and 93 mg/kg at the last follow-up (P < 0.001). CONCLUSIONS: In this population-based sample of Swedish children and young adults the cumulative IBD incidence was 0.74. The validity of register-based definition of IBD was high and supports using such data to identify IBD patients in cohort studies.

Clinical implications of ADHD, ASD, and their co-occurrence in early adulthood-the prospective ABIS-study.

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) are childhood-onset disorders associated with functional and psychosocial impairments that may persist into adulthood, leading to serious personal and societal costs. OBJECTIVE: This study aimed to examine the socio-economic difficulties, physical and mental comorbidities, and psycho-social vulnerabilities associated with ADHD, ASD, and their co-occurrence among young adults. METHODS: 16 365 families with children born 1997-1999, were involved in the prospective population-based ABIS study (All Babies in Southeast Sweden). A total of 6 233 ABIS young adults answered the questionnaire at the 17-19-year follow-up and were included in this case-control study. Diagnoses of ADHD and ASD from birth up to 17 years of age were obtained from the Swedish National Diagnosis Register. N=182 individuals received a single diagnosis of ADHD, n=78 of ASD, and n=51 received both diagnoses and were considered the co-occurrence group. Multiple multinomial logistic regression analyses were performed. RESULTS: In the univariate analyses all three conditions were significantly associated with concentration difficulties, worse health quality, lower socio-economic status, lower faith in the future, less control over life, and lower social support. In the adjusted analyses, individuals with ADHD were almost three-times more likely to have less money compared with their friends (aOR 2.86; p < .001), experienced worse sleep quality (aOR 1.50; p = .043) and concentration difficulties (aOR 1.96; p < .001). ASD group were two-fold more likely to experience concentration difficulties (aOR 2.35; p = .002) and tended not to have faith in the future (aOR .63; p = .055), however, showed lesser risk-taking bahaviours (aOR .40; p < .001). Finally, the co-occurrence was significantly associated with unemployment (aOR 2.64; p = .007) and tended to have a higher risk of autoimmune disorders (aOR 2.41; p = .051), however, showed a 51% lower risk of stomach pain (aOR .49; p = .030). CONCLUSIONS: All these conditions significantly deteriorated several areas of life. ADHD/ASD co-occurrence is a heavy burden for health associated with several psychosocial vulnerabilities, that shared a similar morbidity pattern with ADHD although showed less risk cognitive and behavioral profile, similar to the ASD group. Long-term follow-up and support for individuals with these conditions over the life course are crucial.

Infections in the first year of life and development of beta cell autoimmunity and clinical type 1 diabetes in high-risk individuals: the TRIGR cohort.

AIMS/HYPOTHESIS: Accumulated data suggest that infections in early life contribute to the development of type 1 diabetes. Using data from the Trial to Reduce IDDM in the Genetically at Risk (TRIGR), we set out to assess whether children who later developed diabetes-related autoantibodies and/or clinical type 1 diabetes had different exposure to infections early in life compared with those who did not. METHODS: A cohort of 2159 children with an affected first-degree relative and HLA-conferred susceptibility to type 1 diabetes were recruited between 2002 and 2007 and followed until 2017. Infections were registered prospectively. The relationship between infections in the first year of life and the development of autoantibodies or clinical type 1 diabetes was analysed using univariable and multivariable Cox regression models. As this study was exploratory, no adjustment was made for multiple comparisons. RESULTS: Adjusting for HLA, sex, breastfeeding duration and birth order, those who had seven or more infections during their first year of life were more likely to develop at least one positive type 1 diabetes-related autoantibody (p=0.028, HR 9.166 [95% CI 1.277, 65.81]) compared with those who had no infections. Those who had their first viral infection aged between 6 and 12 months were less likely to develop at least one positive type 1 diabetes-related antibody (p=0.043, HR 0.828 [95% CI 0.690, 0.994]) or multiple antibodies (p=0.0351, HR 0.664 [95% CI 0.453, 0.972]). Those who had ever had an unspecified bacterial infection were more likely to develop at least one positive type 1 diabetes-related autoantibody (p=0.013, HR 1.412 [95% CI 1.075, 1.854]), to develop multiple antibodies (p=0.037, HR 1.652 [95% CI 1.030, 2.649]) and to develop clinical type 1 diabetes (p=0.011, HR 2.066 [95% CI 1.182, 3.613]). CONCLUSIONS/INTERPRETATION: We found weak support for the assumption that viral infections early in life may initiate the autoimmune process or later development of type 1 diabetes. In contrast, certain bacterial infections appeared to increase the risk of both multiple autoantibodies and clinical type 1 diabetes.

High levels of blood circulating immune checkpoint molecules in children with new-onset type 1 diabetes are associated with the risk of developing an additional autoimmune disease.

AIMS/HYPOTHESIS: We assessed the levels of blood circulating immune checkpoint molecules (ICMs) at diagnosis of type 1 diabetes, and determined their association with the risk of developing an additional autoimmune disorder over time. METHODS: Children with new-onset type 1 diabetes (n = 143), without biological and/or clinical signs of additional autoimmune disorders, and healthy children (n = 75) were enrolled, and blood circulating levels of 14 ICMs were measured. The children with type 1 diabetes were divided into two groups on the basis of the development of an additional autoimmune disease in the 5 years after diabetes onset. Differences in soluble ICM levels between the groups were assessed, and a Cox regression analysis was used to evaluate their association with the risk of development of an additional autoimmune disease over time. To validate the data, circulating ICMs were measured in an independent cohort of 60 children with new-onset type 1 diabetes stratified into two groups. RESULTS: We found that the levels of circulating ICMs were significantly higher in children with new-onset diabetes compared with healthy children. Further, we observed that children with type 1 diabetes who developed a second autoimmune disease over time (T1D-AAD+ children) had higher levels of soluble ICMs than children with type 1 diabetes who did not (T1D-AAD- children). Cox regression models revealed that high circulating levels of CD137/4-1BB and PD-1 molecules at diabetes diagnosis were associated with the risk of developing an additional autoimmune disease in both type 1 diabetes cohorts. CONCLUSIONS/INTERPRETATION: Our findings suggest that soluble CD137/4-1BB and PD-1 molecules may be used as prognostic biomarkers in children with type 1 diabetes, and may pave the way for novel immunological screening at diabetes onset, allowing early identification of children at higher risk of developing other autoimmune conditions over time.

Early-life respiratory tract infections and the risk of school-age lower lung function and asthma: a meta-analysis of 150 000 European children.

BACKGROUND: Early-life respiratory tract infections might affect chronic obstructive respiratory diseases, but conclusive studies from general populations are lacking. Our objective was to examine if children with early-life respiratory tract infections had increased risks of lower lung function and asthma at school age. METHODS: We used individual participant data of 150 090 children primarily from the EU Child Cohort Network to examine the associations of upper and lower respiratory tract infections from age 6 months to 5 years with forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC, forced expiratory flow at 75% of FVC (FEF75%) and asthma at a median (range) age of 7 (4-15) years. RESULTS: Children with early-life lower, not upper, respiratory tract infections had a lower school-age FEV1, FEV1/FVC and FEF75% (z-score range: -0.09 (95% CI -0.14- -0.04) to -0.30 (95% CI -0.36- -0.24)). Children with early-life lower respiratory tract infections had a higher increased risk of school-age asthma than those with upper respiratory tract infections (OR range: 2.10 (95% CI 1.98-2.22) to 6.30 (95% CI 5.64-7.04) and 1.25 (95% CI 1.18-1.32) to 1.55 (95% CI 1.47-1.65), respectively). Adjustment for preceding respiratory tract infections slightly decreased the strength of the effects. Observed associations were similar for those with and without early-life wheezing as a proxy for early-life asthma. CONCLUSIONS: Our findings suggest that early-life respiratory tract infections affect development of chronic obstructive respiratory diseases in later life, with the strongest effects for lower respiratory tract infections.

Household income and maternal education in early childhood and risk of overweight and obesity in late childhood: Findings from seven birth cohort studies in six high-income countries.

BACKGROUND/OBJECTIVES: This study analysed the relationship between early childhood socioeconomic status (SES) measured by maternal education and household income and the subsequent development of childhood overweight and obesity. SUBJECTS/METHODS: Data from seven population-representative prospective child cohorts in six high-income countries: United Kingdom, Australia, the Netherlands, Canada (one national cohort and one from the province of Quebec), USA, Sweden. Children were included at birth or within the first 2 years of life. Pooled estimates relate to a total of N = 26,565 included children. Overweight and obesity were defined using International Obesity Task Force (IOTF) cut-offs and measured in late childhood (8-11 years). Risk ratios (RRs) and pooled risk estimates were adjusted for potential confounders (maternal age, ethnicity, child sex). Slope Indexes of Inequality (SII) were estimated to quantify absolute inequality for maternal education and household income. RESULTS: Prevalence ranged from 15.0% overweight and 2.4% obese in the Swedish cohort to 37.6% overweight and 15.8% obese in the US cohort. Overall, across cohorts, social gradients were observed for risk of obesity for both low maternal education (pooled RR: 2.99, 95% CI: 2.07, 4.31) and low household income (pooled RR: 2.69, 95% CI: 1.68, 4.30); between-cohort heterogeneity ranged from negligible to moderate (p: 0.300 to < 0.001). The association between RRs of obesity by income was lowest in Sweden than in other cohorts. CONCLUSIONS: There was a social gradient by maternal education on the risk of childhood obesity in all included cohorts. The SES associations measured by income were more heterogeneous and differed between Sweden versus the other national cohorts; these findings may be attributable to policy differences, including preschool policies, maternity leave, a ban on advertising to children, and universal free school meals.