Season of birth, viral infections, HLA haplogenotypes and non-HLA variants are implicated in the development of celiac disease and celiac disease autoimmunity, suggesting a combined role of genes and environmental exposures. The aim of the study was to further decipher the biological pathways conveying the season of birth effect in celiac disease autoimmunity to gain novel insights into the early pathogenesis of celiac disease. Interactions between season of birth, genetics, and early-life environmental factors on the risk of celiac autoimmunity were investigated in the multicenter TEDDY birth cohort study. Altogether 6523 genetically predisposed children were enrolled to long-term follow-up with prospective sampling and data collection at six research centers in the USA, Germany, Sweden and Finland. Celiac disease autoimmunity was defined as positive tissue transglutaminase antibodies in two consecutive serum samples. There was a significant season of birth effect on the risk of celiac autoimmunity. The effect was dependent on polymorphisms in CD247 gene encoding for CD3 zeta chain of TCR-CD3 complex. In particular, children with major alleles for SNP rs864537A > G, in CD247 (AA genotype) had an excess risk of celiac autoimmunity when born March-August as compared to other months. The interaction of CD247 with season of birth on autoimmunity risk was accompanied by interactions with febrile infections between the ages of 3-6 months. Considering the important role of TCR-CD3 complex in the adaptive immune response and our findings here, CD247 variants and their possible effect of subgroups in autoimmunity development could be of interest in the design of future gene-environment studies of celiac disease.

Purpose We evaluated adherence to a gluten-free diet and associated factors in adult celiac disease patients diagnosed in childhood. Methods Comprehensive medical data on 955 pediatric celiac disease patients was collected and study questionnaires sent to 559 who were now adults. All variables were compared between strictly adherent and non-adherent patients. Results Altogether 237 adults (median age 27 years, 69% women) responded to the questionnaires a median of 18 (range 3–51) years after the childhood diagnosis. Altogether 78% were reportedly adherent and 22% non-adherent. The non-adherent patients had more concomitant type 1 diabetes (18% vs. 4%, p = 0.003), whereas the groups did not differ in demographic data or clinical and histological features at diagnosis, or in short-term dietary adherence. In adulthood, non-adherent patients found gluten-free diet more challenging (39% vs. 17%, p < 0.001) and had higher prevalence (39% vs. 19%, p = 0.004) and severity of symptoms. The main motivation factors for dietary adherence were attempts to avoid symptoms and complications, but these were considered less important and price of gluten-free products more important among non-adherent patients. Adherent and non-adherent patients did not differ in socioeconomic or lifestyle factors, comorbidities other than type 1 diabetes, self-reported general health, health concerns, follow-up, or in quality of life. Conclusion Most originally pediatric celiac disease patients reported strict dietary adherence in adulthood. However, particularly those with concomitant type 1 diabetes, persistent symptoms or financial issues may require attention during the transition from pediatric to adult care.

Background:Celiac disease (CeD) is often accompanied by other autoimmune diseases (AID). However, the association of co-existing autoimmunity with the presentation and treatment success in CeD is unclear. We investigated these issues with a large and well-defined cohort of Finnish patients.Methods:Adult CeD patients (n = 806) were collected from multiple heath care sites via nationwide recruitment. They were interviewed, underwent measurement of CeD autoantibodies, and filled out questionnaires to ascertain quality of life (PGWB) and gastrointestinal symptoms (GSRS) after a median of 9.7 years on a gluten-free diet. Data were supplemented retrospectively from patient records. The results were compared between CeD patients with and without a coexisting AID.Results:Altogether 185 patients had CeD+AID and 621 had CeD only. At CeD diagnosis, patients with CeD+AID were older (median 42 vs. 36 years, p = 0.010) and had more joint symptoms (9.1 vs. 4.2%, p = 0.011), whereas the groups were comparable in sex, family history of CeD, other presenting symptoms, proportion of screen-detected subjects, and severity of duodenal lesion. During follow-up on gluten-free diet, CeD+AID patients experienced poorer general health (median score 12 vs. 14, p < 0.001) in PGWB, more overall gastrointestinal symptoms (2.1 vs. 1.9, p = 0.001), and constipation (2.0 vs. 1.7, p < 0.001) in GSRS, whereas there was no difference in histological and serological recovery, dietary adherence, use of gluten-free oats, smoking, and presence of regular follow-up.Conclusions:Co-existing AID was not significantly associated with the baseline features or with most long-term outcomes in CeD. However, the increased prevalence of gastrointestinal symptoms and reduced poorer self-perceived health during treatment indicates these patients' need for special support.