ABSTRACT
Coeliac autoimmunity [CA] has a known association with type 1 diabetes mellitus [T1DM] for which screening is routinely recommended but less frequently followed. The impact of CA in T1DM has been variably reported. The aims of this study are as follows: [1] to study the prevalence of CA in patients with T1DM and [2] to study the impact of CA not only on nutritional parameters but also on glycaemic control, endocrine axes and bone health. Patients and Eighty-six consecutive patients with T1DM were screened for CA using immunoglobulin A [IgA] tissue transglutaminase as a marker [TTG; IgG anti-gliadin in IgA-deficient case]. CA positive [CA+] cases were compared with age-matched and sex-matched CA negative [CA-] T1DM cases for anthropometry, glycaemic control [assessed by glycated haemoglobin [HbA1c] and hypoglycaemic/ hyperglycaemic episodes], endocrine [thyroid function, cortisol, growth hormone [GH] axis, gonadal axes], haematological [haemoglobin, iron profile and vitamin B12 status] and calcium metabolism parameters and bone densitometry [by dual-energy X-ray absorptiometry [DXA]]. Consenting patients with CA also underwent upper gastrointestinal [GI] endoscopy with duodenal biopsy. Out of 86 patients, 11 [12.75%] screened positive for CA [seven patients underwent duodenal biopsies which were suggestive of Marsh grade III[2], II[3] and I[2] disease]. The CA+ T1DM patients were comparable with CA- T1DM in terms of anthropometry. CA+ patients had higher HbA1c [10.7 +/- 1.8 vs. 8.4 +/- 1.0 [93 +/- 19 vs. 68 +/- 11 mmol/mol]; p < 0.01], more hypoglycaemic episodes [five vs. two; p < 0.05], higher prevalence of iron and vitamin B12 deficiency, lower insulin-like growth factor-1 [IGF- 1] levels and lower bone mineral density [BMD] z-score at total body [-1.91 +/- 1.05 vs. -0.63 +/- 0.73; p < 0.05] and lumbar spine [-1.69 +/- 0.92 vs. 0.36 +/- 0.93; p < 0.05]. The incidence of fractures in the past 3 years was also more in CA+ patients than in CA- patients [four vs. one; p < 0.05]. CA has an important autoimmune association with T1DM. The concomitant presence of CA adversely affects stature, bone health, glycaemic control and iron and B[12] levels in T1DM. IgA sufficiency should be ensured before using an IgA-based screening test for CA