Diabetes is a metabolic disease with chronic endocrine disorders. Due to the widespread use of insulin and antibiotics, death due to ketoacidosis or infection is no longer common, but due to persistent hyperglycemia or hyperglycemic memory, which widely leads to metabolic abnormalities in body tissues and causes various chronic complications is becoming more and more dangerous. Diabetic chronic complications have become an important cause of death and disability in diabetes, and their basic pathological changes are atherosclerosis and microangiopathy, which can involve both large, medium and small arteries, as well as capillaries and veins. So, what are the common chronic complications of diabetes and what are the symptoms and discomfort? 1, diabetic eye complications (1) diabetic retinopathy Diabetic retinopathy is one of the most common complications of diabetes, often aggravated by poor glycemic control, and eventually blindness. Its main cause is microangiopathy within the retinal microcirculation with microthrombosis, which damages the tight junctions of the normal retinal vascular endothelium and causes the retinal barrier to disintegrate. According to domestic literature, the highest number of diabetic patients with retinopathy is 36.6%, 84% of those over 40 years old, and 7% of blindness. The incidence of retinopathy is less than 10% for diabetic patients with less than 5 years of disease, and more than 90% for those with more than 20 years of disease. Diabetic retinopathy can be asymptomatic in the early stage, but with the development of the disease can appear blurred vision, a small ball-like object floating in front of the eyes, the scope of what both eyes can see (medically known as visual field) is significantly smaller than before, the vision at night is obviously not as good as before, and when reading books and newspapers, the vision is less than before, even in the sunlight, and does not feel the sunlight blinding. (2) Diabetic cataracts Diabetic patients have more chances to develop cataracts than ordinary people, and their condition is also heavier than ordinary people. The main reason is the microangiopathy caused by high blood sugar, which aggravates the rate of lens clouding. Symptoms of cataract include loss of vision, blurred vision, feeling very hard on the eyes when reading or doing needlework, even unable to do it, always feeling a layer of fog in front of the eyes, always wanting to rub the eyes will see more clearly but not much help, always feeling dazzled by sunlight and lights, especially the lights of oncoming cars at night, the color of the pupil (commonly called black eye) changes from black to gray. 2, diabetic nephropathy Diabetic nephropathy refers to diabetic glomerulosclerosis, a kind of glomerulopathy with vascular damage as the main cause. In the early stage, it is mostly asymptomatic, and the blood pressure may be normal or high. Urinary microalbumin excretion >200 mcg/min measured by radioimmunoassay, this stage is called occult nephropathy, or early nephropathy. If hypertension and hyperglycemia can be actively controlled, the lesion can be expected to improve. If poorly controlled, with the progress of the lesion may develop into clinical diabetic nephropathy, which may have the following clinical manifestations: proteinuria, swelling, hypertension, renal insufficiency, anemia and other symptoms. Diabetic neuropathy is a serious complication of diabetes mellitus and is an important cause of death and disability in diabetic patients. The cause of diabetic neuropathy is the direct destructive effect of long-term hyperglycemia on nerve cells and long-term hyperglycemia that damages the blood supply vessels of nerve cells. Depending on the location of the impact, the diabetic neuropathy can be divided into: peripheral neuropathy, motor neuropathy, sensory neuropathy, and autonomic neuropathy. In the early stage, diabetic neuropathy can have no obvious clinical symptoms, and in the late stage, obvious clinical symptoms can appear, including: spontaneous pain, which is worse at night and sometimes makes you sleepless at night; loss of sensation-like numbness, walking with feet feeling like stepping on cotton; abnormal sensation, such as burning sensation, inability to distinguish hot from cold or hypersensitivity to hot and cold, insensitivity or hypersensitivity to pain, having The sensation of “ants crawling through”, etc.; often have the feeling of cold or hot hands and feet; abnormal sweating, including upper body sweating or lower body sweating, sweating when eating, etc.; abnormal bladder function, the patient can not control urination; abnormal digestive tract may appear diarrhea, constipation, or alternating diarrhea and constipation, nausea, vomiting, vomit has a sour odor; upright hypotension, when from a sitting position to a sitting position, the patient can not control urination. When suddenly standing up from a sitting position, there is dizziness, the feeling of blackness in front of the eyes, and even fainting in serious cases; sexual function abnormalities, male and female parts can appear sexual hypogonadism, in men and even impotence. 4, diabetic hypertension Diabetes mellitus and hypertension are complex, and they often exist together and affect each other. Diabetic patients suffering from hypertension is 2-4 times more than ordinary people. 5, diabetic heart disease diabetic heart disease is a diabetic patient in the sugar, fat and other metabolic disorders based on the occurrence of cardiac macrovascular, microvascular, myocardial and neurofibrillary lesions. The main manifestations are heart rate greater than 90 beats/min at rest, or fast and fixed heart rate, not affected by various reflexes; atypical angina pectoris; painless myocardial infarction; upright hypotension; sudden death, etc. Diabetes combined with coronary artery disease is 2-4 times more common in non-diabetic people. 6, diabetic foot Diabetic foot is mainly due to persistent hyperglycemia leading to arterial narrowing, resulting in limb ischemia, neuropathy, infection and the interaction of a variety of predisposing factors, and due to the lack of timely treatment resulting in gangrene of the extremity. The main manifestations are sweatless, coarse cracking of the skin of the lower limbs and feet; numbness, tingling, burning pain or loss of sensation in the hands and feet; muscle atrophy, poor elasticity of dry skin, decreased skin temperature, darkening of the skin; intermittent claudication; weakening or disappearance of arterial erosion.