Effect of Gluten-Free Diet on Metabolic Control and Growth Parameters Among Children and Adolescents With Type 1 Diabetes During the First Year After Diagnosis of Celiac Disease: A Retrospective Case-Control Study.

Aims: Assessment of celiac disease and gluten-free diet (GFD) associations with metabolic control and growth parameters in children and adolescents with type 1 diabetes mellitus (T1DM) during the first year after diagnosis of celiac disease. Methods: This was a retrospective case-control study that included 47 children and adolescents with T1DM aged <18 years who attended the pediatric diabetes clinic at Sohag University Hospital, Egypt, and had a biopsy-proven diagnosis of celiac disease between January 2017 and December 2021. Each case had two age-, sex-, and duration of diabetes-matched control participants with T1DM who had persistently negative celiac screening tests. Clinical characteristics, growth parameters, insulin doses, celiac autoantibody titers, and HbA1c levels throughout the first year after diagnosis of celiac disease were obtained from the medical records. Results: Children and adolescents with celiac disease had significantly lower insulin doses at diagnosis (p=0.002) compared to their matched controls. There were no significant differences between both groups regarding the HbA1c levels at diagnosis of celiac disease or after 1 year (p=0.27 and 0.81, respectively). Patients with celiac disease had significantly lower weight, height, and body mass index (BMI) standard deviation scores (SDSs) at diagnosis and after 1 year. There were no significant differences between both groups regarding the fasting lipid profiles at diagnosis or after 1 year. Patients with villous atrophy at diagnosis had significantly higher HbA1c levels after 1 year (p=0.04). There were no significant improvements in weight, height, and BMI SDS after 1 year even in patients with normalized celiac autoantibodies. Conclusions: Children and adolescents with T1DM had lower insulin requirements and growth parameters at diagnosis of celiac disease. Villous atrophy at diagnostic small bowel biopsies was associated with worsening glycemic control after 1 year. Longer follow-up periods are required to detect significant improvements in growth parameters.