Abstract: Objective To investigate the clinical characteristics of different subtypes of type 1 diabetes mellitus(T1DM) patients and to analyze the risk of macrovascular diseases in different subtypes of T1DM patients. Methods The clinical data among 79 T1DM patients who treated in the Endocrinology Department of Beijing Puren Hospital from March 2002 to July 2021 were retrospectively analyzed. There were 21 patients with idiopathic T1DM and 58 patients with autoimmune T1DM. Excluding 14 patients because of data missing, 65 patients were divided into macrovascular disease group (n=13) and non-macrovascular disease group (n=52). Results 1)Patients with idiopathic T1DM manifested a longer diabetic course,a higher high density lipoprotein cholesterol(HDL-c)level, a lower body mass index(BMI), hemoglobin A1c(HbA1c) and fasting C peptide(FC-P)level. 2)Compared with the group non-macrovascular disease, the macrovascular disease group was elder with higher prevalence of idiopathic T1DM and lower estimated glomerular filtration rate(eGFR) level and incidence of diabetic ketoacidosis(DKA) at the beginning of disease. 3)Macrovascular lesions were positively correlated with age(r=0.432) and diabetic course (r=0.245)(P＜0.05), were negatively correlated with eGFR(r=-0.392), positive islet autoantibody (r=-0.268) and DKA incidence at the beginning of disease(r=-0.313)(P＜0.05). 4)Multivariate regression analysis showed that negative auto-antibody finding was a risk factor for macrovascular disease (OR=0.03, 95% CI:0.001-0.858, P＜0.05) after age, diabetic course, BMI, eGFR, HDL-c and incidence of DKA at onset were adjusted. Conclusions Patients with idiopathic T1DM show a higher risk of macrovascular disease risk than those with autoimmune T1DM.

Key words: type 1 diabetes mellitus, macrovascular diseases, idiopathic, autoimmunity, islet autoantibody