Lower HbA1c in patients with type 1 diabetes and celiac disease who reached celiac‐specific antibody‐negativity—A multicenter DPV analysis

OBJECTIVES: To study celiac‐specific antibody status over 3 years in patients with type 1 diabetes and biopsy‐proven celiac disease (T1D + CD). Furthermore, to determine clinical differences after diagnosis between patients reaching constant antibody‐negativity (Ab‐neg) and staying antibody‐positive (Ab‐pos). METHODS: A total of 608 pediatric T1D + CD patients from the multicenter DPV registry were studied longitudinally regarding their CD specific antibody‐status. Differences between Ab‐neg (n = 218) and Ab‐pos (n = 158) patients 3 years after biopsy were assessed and compared with 26 833 T1D patients without CD by linear and logistic regression adjusted for age, gender, diabetes duration and migration background. RESULTS: Thirty‐six percent of T1D + CD patients reached and sustained antibody‐negativity 3 years after CD diagnosis. The median time until patients returned to Ab‐neg was 0.86 (0.51;1.16) years. Three years after diagnosis, HbA1c was lowest in Ab‐neg and highest in Ab‐pos patients compared to T1D‐only patients (adjusted mean (95%CI): 7.72 (7.51‐7.92) % vs 8.44 (8.20‐8.68) % vs 8.19 (8.17‐8.21) %, adjusted P < 0.001, respectively). Total cholesterol, LDL‐cholesterol and frequency of dyslipidemia were significantly lower in Ab‐neg compared to T1D‐only patients (167 (161‐173) mg/dl vs 179 (178‐179) mg/dl, P < .001; 90 (84‐96) mg/dl vs 99 (98‐99) mg/dl, P = .005; 15.7 (10.5‐22.9) % vs 25.9 (25.2‐26.6) %, P = .017). In longitudinal analyses over 6 years after diagnosis, a constantly higher HbA1c (P < .001) and a lower height‐SDS (P = .044) was observed in Ab‐pos compared to Ab‐neg patients. CONCLUSION: Only one third of T1D + CD patients reached constant Ab‐negativity after CD diagnosis. Achieving Ab‐negativity after diagnosis seems to be associated with better metabolic control and growth, supposedly due to a higher adherence to therapy in general.