Irregular follow-up is associated with poorer dietary adherence and iron deficiency in children with celiac disease.

The purpose of this study is to evaluate the association between follow-up regularity and dietary adherence, growth, and micronutrient status in children with celiac disease (CD). In this single-center, prospective observational study, children on a gluten-free diet (GFD) for ≥ 1 year were classified over a fixed 24-month window as regular follow-up (RFU; ≥ 4 visits) or irregular follow-up (IFU; < 4 visits) according to the number of outpatient visits. Adherence was assessed by parent- and child-reported modified Biagi scores and by anti-tissue transglutaminase IgA (TGA) normalization (< 20 RU/mL). Multivariable models were adjusted for age, sex, time since diagnosis, and socioeconomic status (SES). Of 345 children, 204 were RFU and 141 IFU; the median number of visits was 5 (IQR 4-5) versus 2 (1-3), respectively (p < 0.001). Children in the IFU group were older and more often of low SES. Non-normalization of TGA was independently associated with IFU (adjusted odds ratio (aOR): 3.16; 95% CI, 1.97-5.06); each additional visit lowered the odds of non-adherence (aOR, 0.66; 95% CI, 0.57-0.77). IFU was associated with non-strict parent-reported adherence (aOR, 2.20) and iron deficiency (aOR, 1.97). Parent-reported adherence correlated moderately with TGA status (κ = 0.46), whereas child self-report adherence was negligible (κ = 0.05). The lower BMI z-score in the IFU group lost significance after adjustment.Conclusion: More frequent follow-up improved GFD adherence, as reflected by normalized TGA levels; IFU was independently associated with poorer adherence and iron deficiency. Low GFD compliance is most likely among older and low-SES children. For children aged ≥ 10, self-reported adherence is unreliable; parental report with serology is preferable.