Association Between Celiac Disease and Uncontrolled Hemoglobin A1c Levels in Type 1 Diabetes Pediatric Patients

Celiac disease (CD) occurs in ~6% of individuals with type 1 diabetes (T1D) and may complicate glycemic control due to conflicting dietary needs. Prior studies show mixed results regarding the impact of CD on Hemoglobin A1c (HbA1c), especially in pediatric populations. This study evaluates whether CD is associated with suboptimal glycemic control in pediatric patients with T1D.

This retrospective chart review analyzed pediatric patients (<18 years) diagnosed with T1D between 2012 and 2023 across Corewell Health East. Patients were identified via ICD-10 codes and stratified by CD status and glycemic control (controlled HbA1c <7% vs. uncontrolled HbA1c ≥7%). Statistical analyses include chi-square or Fisher's exact tests for categorical variables, Wilcoxon tests for continuous variables, and logistic regression for multivariable analysis.

Among 2,203 pediatric patients with T1D, 101 (4.6%) had CD. Patients with both conditions were younger at T1D diagnosis (median age 9 vs. 12 years, p < 0.0001) and had more HbA1c measurements. A higher proportion of CD patients had uncontrolled diabetes (89.1% vs. 73.8%, p = 0.0006). CD was independently associated with uncontrolled HbA1c (adjusted OR: 2.59; 95% CI: 1.37-4.90; p = 0.003) after adjusting for age, sex, and race. Younger age and Black race were also associated with higher odds of uncontrolled diabetes.

CD is significantly associated with poorer glycemic control in pediatric patients with T1D, independent of age, race, and sex. These findings suggest the need for closer monitoring, individualized dietary counseling, and targeted interventions in this high-risk group.