Endocrine Abstracts

Introduction: Type 1 diabetes mellitus (T1DM) is considered, in general, a disease of children and young adults with normal body mass index (BMI), linked to a genetic susceptibility based on autoimmunity. However, we know that it can be diagnosed at any age and we must differentiate it from type 2 diabetes mellitus.

Objetives: To investigate the phenotypic characteristics and the presence of specific autoimmunity in T1DM patients diagnosed in our hospital.

Material and methods: We performed a descriptive observational study, including patients first diagnosed with T1DM between 2013 and 2017. They have been followed during the last year, in the Diabetes Onset clinic at Virgen de la Victoria Hospital in Málaga. We analyzed the clinical features and autoimmunity, pancreatic reserve and glicated haemoglobin (HbA1c) at onset of diabetes.

Results: We analyzed data from 69 patients with mean age 26 (±10.8 years), 61% males; IMC 23.6±3.8. 47.8% had a family history of diabetes: 24.6% T1DM and 23.2% type 2 diabetes (T2DM). Only 1.4% had autoimmune thyroid disease prior to the diagnosis of diabetes. The presentation onset of the disease was: 17.4% diagnosed casually without symptoms; 59.4% presented cardinal symptoms of diabetes; 21.7% suffered ketoacidosis and, only 7.2% required hospital admission. None of the patients died in that initial event. The autoimmunity at debut was analyzed: 47.8% had positive anti-IA2 antibodies and 92.8% positive anti-GAD antibodies. 4% had negative autoimmunity. All patients presented a decreased pancreatic reserve with C peptide values at diagnosis 1.2±0.9 ng/mL and insulin values 5±3.4 μU/mL. They had poor metabolic control (HbA1c 13.2%) that precipitated the diagnosis.

Conclusions: Nowadays we have a major difficulty to identify T1DM after 30 years due to the increasing prevalence of DM2 background. It requires the determination of autoimmunity as a useful marker to demonstrate the presence of disease. Failure to diagnose late-onset T1DM could have serious consequences due to early development of insulin dependence.