They are both diabetes, what is the difference between type 1 and type 2?

Author: Tang Qin, Researcher of Chinese Medical Association

Reviewer: Zhang Tingting, deputy chief physician, Peking University First Hospital

Diabetes is a heterogeneous metabolic disease characterized by chronic hyperglycemia caused by genetic, autoimmune, environmental and other factors. The two types of diabetes that most people have heard of are type 1 diabetes and type 2 diabetes. Some patients see the progression in numbers and think that type 2 is more serious than type 1.

So, is this true?

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1. The two types of diabetes have different pathogenesis

In fact, although there is a progressive relationship between type 1 and type 2 diabetes in numbers, it does not mean that type 2 diabetes is more serious than type 1. Because from the perspective of pathogenesis, the two are two different types of diabetes and are not comparable.

Most cases of type 1 diabetes are caused by the destruction of pancreatic β cells, which leads to an absolute lack of insulin. For example, the pancreas is the factory in the body responsible for processing and producing insulin. Without the raw material pancreatic β cells, it cannot produce insulin to regulate the body's blood sugar, which will lead to a series of metabolic problems.

Type 2 diabetes is caused by a variety of factors that lead to insufficient insulin secretion in the body or insulin resistance. In other words, the reason is not the lack of pancreatic β cells, but because of their insufficient productivity and production capacity, they cannot produce enough insulin, or the insulin produced by pancreatic β cells is not lacking, but the body's cells are less sensitive to insulin, which causes the body to need more insulin to stimulate them, thus causing blood sugar disorders in the body.

2. There are three major differences between the two types of diabetes

In addition to the different pathogenesis, there are three other differences between type 1 diabetes and type 2 diabetes.

First, in terms of the age of onset, the age of onset of type 1 diabetes is generally relatively young. Studies have shown that most diabetes patients among adolescents and children in my country are type 1 diabetes, while adults of all ages can develop the disease; type 2 diabetes is generally more common in people over 40 years old.

Secondly, from the perspective of clinical symptoms, type 1 diabetes has an acute onset and has the typical symptoms of "three mores and one less" (i.e., more drinking, more eating, more urination, and weight loss). Therefore, most of these patients are of normal or thin body shape. However, type 2 diabetes has a slow onset and is difficult to detect early. The symptoms of "three mores and one less" are not obvious, and abnormal blood sugar is usually discovered during a physical examination or when feeling unwell. Among these patients, there are many obese people.

Finally, from the perspective of complications, the main complication that endangers the life and health of patients with type 1 diabetes is renal insufficiency caused by diabetic nephropathy, while the main complication that endangers the life and health of patients with type 2 diabetes is diabetic macrovascular disease, such as cardiovascular and cerebrovascular diseases.

3. There are differences in the treatment of the two types of diabetes

1. Treatment of type 1 diabetes

For type 1 diabetes, insulin therapy is mainly used to control the patient's blood sugar within the target range and prevent the occurrence of hypoglycemia. Therefore, patients with type 1 diabetes need insulin therapy when they are diagnosed and need to use it for life. Depending on the severity of the disease, the type of insulin used may be different. For patients with relatively mild conditions and small blood sugar fluctuations, premixed insulin analogs or dual insulin (a drug that mixes rapid-acting and medium/long-acting insulin analogs in proportion) can be considered for treatment. For patients with more serious conditions and large blood sugar fluctuations, multiple insulin treatments are generally required every day, such as using rapid-acting insulin analogs before meals and long-acting insulin analogs before bedtime. That is, insulin treatment is given to patients by simulating the insulin secretion under human physiological conditions.

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With the development of medicine, insulin pump therapy can also be used, but this method must be determined based on the patient's age, condition and whether the patient can master the use of insulin pumps. It should be noted that since most of these patients are children and adolescents, family members should pay attention to ensuring dietary nutrition and proper exercise in their daily lives when taking care of these patients to maintain their normal growth and development.

2. Treatment of type 2 diabetes

There are relatively many treatment options for type 2 diabetes.

The doctor will first ask the patient to alleviate the condition by improving his diet and living habits and exercising appropriately. If this still does not bring the blood sugar level up to the standard, the doctor will consider using medication in a timely manner.

Generally speaking, most patients with type 2 diabetes will first choose biguanides (such as metformin). For non-obese patients with type 2 diabetes with a short course of disease and acceptable pancreatic islet function, sulfonylureas such as glipizide, gliclazide, and gliclazide can be considered. For patients with type 2 diabetes with postprandial blood sugar elevation, glinides such as repaglinide and nateglinide, or α-glucosidase inhibitors (such as acarbose) can be considered. For patients with concomitant heart failure, chronic kidney disease, and atherosclerotic cardiovascular disease, sodium-glucose co-transporter 2 inhibitors such as canagliflozin, dapagliflozin, and empagliflozin can be considered. If oral hypoglycemic drugs are ineffective or the patient has contraindications to oral drugs, subcutaneous injections of insulin or glucagon-like peptide-1 receptor agonists can be used to control hyperglycemia and reduce the risk of diabetic complications.

If it is impossible to distinguish between type 1 and type 2 at the onset of the disease, insulin therapy can be used to stabilize blood sugar, and then the diagnosis can be further confirmed by monitoring pancreatic islet function. This is why doctors recommend that some patients use insulin therapy first and then return for a follow-up visit when the type of diabetes is not determined.

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There is no saying that type 1 diabetes is more serious than type 2 diabetes, so no matter which type of diabetes you have, you don't need to be afraid of sugar. As long as you control your blood sugar, you can improve your quality of life. In daily life, patients should pay attention to controlling their diet, doing scientific and appropriate exercise, and actively communicate with their doctors regularly about their condition to prevent various complications.

References

[1] Cheng Shulin. Exercise and type 2 diabetes[M]. Shanghai: Shanghai Jiaotong University Press, 2022.

[2] Weng Jianping, Ji Linong, Dong Siping. Integrated medical management pathway for type 1 diabetes[M]. Beijing: People's Medical Publishing House, 2021.