The aim of this research was to study the clinical features and microvascular complications risk factors of early-onset type 2 diabetes mellitus (T2DM). We analyzed the clinical data from 1421 T2DM inpatients at Wuhan Union Hospital. Subjects were divided into early-onset T2DM group (diagnostic age <40 years) and late-onset T2DM group (diagnostic age >40 years). All subjects underwent a standardized assessment of microvascular complications. Data were compared with independent-samples t test or Chi-square test. Multiple logistic regression was used to determine the risk factors of microvascular complications. Patients with early-onset T2DM were more inclined to have a lower systolic blood pressure (SBP), a longer duration of diabetes and higher levels of body mass index (BMI), uric acid (UA), fasting plasma glucose (FPG), total cholesterol (TC)- triglyceride (TG) and glycosylated hemoglobin (HbA1c) than those with late-onset T2DM (P<0.05). The prevalence of diabetic retinopathy (DR) was significantly higher and that of diabetic peripheral neuropathy (DPN) was significantly lower in early-onset group than in late-onset group (P<0.05). For DN, UA was an independent risk factor in early-onset T2DM. SBP and TG were independent risk factors in late-onset T2DM. For DR, duration of diabetes and SBP were independent risk factors in early-onset T2DM. Duration of diabetes, SBP and HbA1c were independent risk factors in late-onset T2DM. This study demonstrated that the clinical characteristics of early-onset T2DM were metabolic disorders, including glucose metabolism, lipid metabolism and amino acid metabolism. Early-onset T2DM was more likely to be associated with DR. The potential pathogenesis of early and late-onset T2DM might be different. The management of metabolic risk factors especially HbA1c, SBP, TG and UA is advised to be performed in the early stage of diabetes.
