Gastrointestinal Symptoms in Type 1 Diabetes: Relationship With Autoimmune and Microvascular Complications.

Purpose: To assess reported rates of gastrointestinal (GI) symptoms and their association with autoimmune diseases and microvascular complications in adults and children with type 1 diabetes.

Methods: The Gastrointestinal Symptom Scale was used to assess GI symptom type and severity in 2370 patients with type 1 diabetes aged 8 to 45 years evaluated as part of a clinical trial screening for celiac disease (CD). The presence and severity of GI symptoms and relationships with demographic, clinical, and other diabetes-related factors were evaluated.

Results: Overall, 1368 adults (57.7%) aged 19 to 45 years and 1002 (42.3%) pediatric patients aged 8 to 18 years were studied. At least 1 GI symptom was reported in 34.1% of adults as compared with 21.7% of children (P < 0.0001). Common symptoms in children included upper and lower abdominal pain while adults more frequently reported lower GI symptoms. Participants with GI symptoms had higher hemoglobin A1c (HbA1c) levels (68 ± 14mmol/mol; 8.35 ± 1.37%) than those without symptoms (66 ± 15mmol/mol; 8.22 ± 1.40%; P = 0.041). Patients with microvascular complications (nephropathy, retinopathy, and/or neuropathy) were 1.8 times more likely to report GI symptoms (95% CI: 1.26-2.60; P < 0.01) after adjusting for age and sex. No association was observed between GI symptoms and the presence of autoimmune conditions, including thyroid and biopsy-confirmed CD (odds ratio = 1.1; 95% CI: 0.86-1.42; P = 0.45).

Main Conclusions: These results highlight that GI symptoms are an important clinical morbidity and are associated with increasing age, duration of type 1 diabetes, HbA1c, and microvascular complications but not with autoimmune comorbidities including CD.