Signs of diabetes deterioration mainly include poor blood glucose control, blurred vision, diabetic foot and diabetic nephropathy. 1. Poor blood sugar control: high blood sugar is a clear sign of deterioration of diabetes, if the dose of glucose-lowering drugs or insulin injections can no longer effectively control blood sugar, you need to consult a doctor in a timely manner to increase the dose of medication or adjust the medication regimen under the guidance of the doctor. 2. Blurred vision: diabetes is a systemic metabolic disease, high blood sugar will destroy the fundus microvessels, inducing diabetic retinopathy, which will affect vision, manifested as blurred vision, and in severe cases, it will lead to retinal detachment and even blindness. 3. Diabetic foot: diabetic foot blood vessels, nerve lesions, resulting in insufficient blood supply to the foot, sensory abnormalities, and ulceration, infection symptoms. Severe cases can also affect the muscles and bones of diabetic patients, leading to tissue necrosis, and even require amputation. 4. Diabetic nephropathy: diabetic patients with long-term poor glycemic control may affect renal function, and in severe cases, renal failure occurs, requiring dialysis therapy for treatment. 5. Accompanying other diseases: such as hypertension, hyperlipidemia, cardiovascular and cerebral vascular diseases, gout and so on. Diabetes mellitus is a chronic disease, must follow the doctor’s instructions for medication, so that blood sugar to maintain a reasonable range, so as to avoid deterioration of the condition.