There is no exact time for the emergence of complications in type 1 diabetic patients. It is generally closely related to the duration of the onset of the disease, and if the blood glucose control is good, it may take ten years, or even longer, before the emergence of complications, such as diabetic nephropathy, atherosclerosis, and diabetic neuropathy. 1. Diabetic nephropathy: It is the main cause of death in type 1 diabetes mellitus, and diabetic nephropathy is one of the most important microvascular complications of diabetes mellitus. The common clinical symptoms are large amount of proteinuria, hypertension, edema and so on. 2. Atherosclerotic: diabetic people have higher probability of suffering from atherosclerosis, with early onset and rapid progression of the disease, which mainly infringes on the aorta, cerebral arteries, coronary arteries, renal arteries, and arteries of the limbs, etc., and causes coronary artery disease, atherosclerosis of the limbs, and ischemic or hemorrhagic cerebrovascular disease. 3. Diabetic neuropathy: diabetic neuropathy is one of the most common chronic complications of diabetes mellitus, including polyneuropathy, mononeuropathy and autonomic neuropathy, and the lesions can involve the central nerves as well as peripheral nerves of patients. Type 1 diabetes is a kind of diabetes caused by the destruction of pancreatic β-cells and the absolute insufficiency of insulin, and the treatment methods include dietary treatment, exercise treatment and insulin treatment. It is recommended that if patients are found to have type 1 diabetes, they should be treated under the guidance of a doctor in a timely manner, so as not to delay the condition and avoid causing complications such as diabetic nephropathy. Daily need to use rapid blood glucose meter for self-monitoring.