Chronic disease classification

For clinical diagnosis and treatment, it is divided by cause/involved system, and for public health prevention and control, it is divided by intervention priority/degree of harm. The specific classification depends entirely on the usage scenario, and there is no absolute right or wrong.

First, let’s talk about the classification logic that we most often encounter when we go to the hospital to see a doctor. To put it bluntly, they are grouped according to the place and cause of illness: for example, the commonly heard of hypertension, coronary heart disease, and stroke are chronic diseases of the circulatory system, chronic obstructive pulmonary disease, and asthma are classified into the respiratory system, and diabetes, Gout and dyslipidemia are endocrine and metabolic diseases, and there are rheumatic immune chronic diseases such as rheumatoid arthritis and ankylosing spondylitis, neurological chronic diseases such as Alzheimer's disease and Parkinson's disease, and chronic diseases involving local tissues such as osteoarthritis and chronic periodontitis. There is actually a point that has been controversial for several years: does malignant tumor count as a chronic disease? Those who support it are based on WHO standards and believe that malignant tumors have a long course and require long-term follow-up management, which fully meets the definition of chronic diseases. The Global Chronic Disease Report released by WHO in 2020 has included malignant tumors in the category of chronic diseases. ； However, most of the opponents are doctors in the clinical oncology department. They feel that the treatment logic and prognosis of tumors are too different from those of ordinary chronic diseases. It is more convenient for diagnosis and treatment to separate them into a separate category. There is no unified conclusion between the two views. When encountering related problems in daily life, most of them depend on the practices of the hospital where they are located.

If the scene changes, when it comes to grassroots public health prevention and control, the classification standards have completely changed. After all, public health resources are limited, and it is impossible to include all chronic diseases in key management, so they are prioritized according to the degree of harm and incidence: hypertension, type 2 diabetes, coronary heart disease, stroke, chronic obstructive pulmonary disease, and severe mental disorders are the six categories that the national basic public health clearly requires to focus on management. They account for more than 80% of the causes of death and disability caused by chronic diseases in my country, and are the highest priority categories. ； The remaining diseases, such as chronic gastritis, chronic pharyngitis, and rheumatoid arthritis, which have high incidence rates but low mortality risks, are classified as general chronic diseases and will not be forced to be included in community ledger management. When I worked in a community chronic disease post for the past two years, the most annoying thing was that my superiors had to fill in the classification of patients with comorbidities as the only option when checking. How can it be so rigid in reality? Several elderly people have high blood pressure, diabetes, and chronic obstructive pulmonary disease at the same time. We prioritize the ones with the highest risk for follow-up, and manage the rest simultaneously. If we really have to figure out the rules of classification, we can't do the work. I met a patient before and asked, I have diabetes and chronic periodontitis, why does the community only register diabetes for me? In fact, it is a problem with this classification logic. Periodontitis is indeed a chronic disease, but it does not fall into the category of key public health control. This does not mean that this disease should not be taken care of.

In the past two years, a more practical classification idea has emerged in the field of clinical chronic disease management, which is not based on system or harm, but on whether it can be reversed: for example, early grade 1 hypertension (which has not yet damaged target organs such as the heart, kidneys, and blood vessels), impaired glucose tolerance, simple mild fatty liver, and early hyperuricemia. These are all reversible chronic diseases. As long as you adjust your diet, exercise, and work schedule, you will most likely be able to return to a completely normal state in half a year to a year, without the need for long-term medication.； Hypertension, diagnosed type 2 diabetes, chronic obstructive pulmonary disease, and mid- to late-stage malignant tumors that have already caused target organ damage, even if they are irreversible chronic diseases, require long-term medication or intervention to control the progression of the disease. Last year, I took care of a 32-year-old young man who was diagnosed with grade 1 hypertension and mild fatty liver. According to the previous system, he was classified into two departments. According to the reversibility classification, he was directly classified into the lifestyle intervention group. I gave him 3 months of dietary and exercise guidance. His blood pressure stabilized at 120/80 and the fatty liver disappeared. If he was classified as a common chronic disease in the long-term medication group from the beginning, it would only put a psychological burden on him.

In fact, to put it bluntly, chronic disease classification is like setting up shelves in a supermarket. Whether you place them by category or by promotion priority depends entirely on whether you want to make it easier for customers to find goods or to increase sales. In essence, they are just tools to serve the goal. There is really no need to worry about which standard is absolutely correct. I used to help a junior student in the medical school revise his graduation thesis. He insisted on classifying all chronic diseases according to unified standards. He was stuck for half a month and couldn't figure it out. I told him that you should first figure out what the scenario of your research is - if you are doing clinical drug research, classify it according to the system. If you are doing community prevention and control research, classify it according to the public health priority. Set the scenario first and then choose the classification standard. The problem is solved instantly. After all, chronic diseases in reality are never classified according to classification standards. Many patients with co-morbidities have problems across three or four systems. They get stuck on classification and forget that the original intention of classification is to better help patients solve their problems.