Elevated blood glucose indicates changes in blood glucose metabolism in the body, and there are several possibilities. First, there is a problem with insulin secretion, because insulin is an important hormone for blood glucose metabolism. Insufficient insulin secretion or insulin resistance will cause changes in blood glucose. Second, liver problems, the liver plays a very important role in the storage and transformation of blood sugar, if the liver has problems, it will also lead to an increase in blood sugar. Thirdly, some diseases can secrete hormones that antagonize insulin, such as growth hormone tumor, cortisolism, hyperthyroidism and other diseases, and the increased secretion of hormones that antagonize insulin will antagonize the hypoglycemic effect of insulin and lead to elevated blood sugar. Patients who have elevated blood glucose need to undergo appropriate islet function tests, endocrine hormone tests and liver function tests to clarify the specific cause of elevated blood glucose.