Introduction: Adult-onset autoimmune diabetes (AID) has two different phenotypes: classic type 1 diabetes mellitus (T1DM), with insulin requirement just after diagnosis, and latent autoimmune diabetes in adults (LADA). According to the Immunology of Diabetes Society, LADA diagnostic criteria are: age of onset of 30 years or more, any islet autoantibody, absence of insulin requirement for at least 6 months. The purpose of this study is to characterize patients with AID followed on a tertiary centre, comparing classic T1DM and LADA.
Methods: We collected data from patients with diabetes and positive islet autoantibodies, with at least 30 years at diagnosis. We classified patients who started insulin in the first 6 months as T1DM and patients with no insulin requirements in the first 6 months as LADA. Data regarding presentation, autoantibodies, A1C and C-peptide at diagnosis, therapeutics and complications were analysed with SPSS.
Results: Ninety-two patients included, 46 with T1DM and 46 with LADA. In T1DM group, 50% female, in LADA 52.1%. The median age at diagnosis was 38 years in T1DM group and 42 years in LADA group. The median follow-up time after diabetes diagnosis was 8 years in T1DM and 11 years in LADA (P=0.023). The median time between diagnosis of diabetes and diagnosis of autoimmune cause was 0 months in T1DM and 60 months in LADA (P<0.001). The mean BMI at diagnosis was 23.52 kg/m2 in T1DM and 26.07 kg/m2 in LADA (P=0.023). The median number of positive autoantibodies was 2 in T1DM and 1 in LADA (P=0.013). There was no statistical difference between both groups in what concerns to title of GAD autoantibodies, A1C and C-peptide at diagnosis of autoimmune aetiology. The presence of symptoms at diagnosis was associated with T1DM group (P<0.001). There was no difference between both groups in A1C, lipid profile, glomerular filtration rate and BMI at the last evaluation. LADA group was associated with macroalbuminuria (P=0.042). The median daily insulin dose was 40U for T1DM and 33.5U for LADA. Patients in LADA group used more often non insulin antidiabetic drugs (P=0.001). There were no differences on other diabetes complications.
Conclusion: Patients with classic T1DM presented more often with symptoms at diagnosis, lower BMI and higher number of autoantibodies, which may be related to a more aggressive autoimmune process. Patients with LADA were associated with macroalbuminuria and were more often under non insulin antidiabetic drugs. The ideal treatment of LADA is yet to be identified.
19 - 22 May 2018
European Society of Endocrinology