What is cognitive impairment? Will it develop into dementia?

Author: Liu Chunyan, deputy chief physician of Aviation General Hospital

Reviewer: Xing Yan, Chief Physician of Aviation General Hospital

We humans go through the process of learning and problem solving every day, such as simple ones, such as going to the market to buy vegetables, selecting vegetables and paying; there are also complex ones, such as leading the employees of a company.

Whether it is simple or complex, in this process, our brain needs some basic components to ensure the completion of learning and problem solving. These basic components include orientation, attention, memory, as well as thinking, language, executive function, etc., collectively referred to as cognitive function.

If a patient develops problems in one or more areas after becoming ill, such as damage to attention, memory, executive function, and language, it is collectively referred to as cognitive dysfunction.

Cognitive dysfunction is a general term that covers the progression of disease from mild cognitive impairment to mild, moderate, and severe dementia.

Mild cognitive impairment actually means that the patient's attention or memory is damaged, but this damage does not affect the patient's daily life ability. It can be found through professional examinations. Doctors will use some standardized scales to check some memory or attention damage.

Data published in The Lancet in December 2020 showed that there are approximately 37 to 38 million patients with mild cognitive impairment in my country, which is a huge number.

Figure 1 Original copyright image, no permission to reprint

Once the patient reaches the dementia stage, what we can do is very limited. We can only try to delay the disease and prevent it from progressing too quickly. Our current medical development cannot completely solve this problem.

There are many patients with cognitive impairment clinically. They can walk and talk, but have lost their ability to learn and work. This is a devastating injury.

We all know that any disease, if it invades some parts of the brain related to cognitive functions, such as the frontal lobe, temporal lobe, and parietal lobe, will cause corresponding cognitive damage.

Therefore, if the disease can be detected early, intervention and rehabilitation training can be carried out early, some early patients can be reversed.

If the patient does not receive training and early intervention, he will gradually develop from mild cognitive impairment to dementia. At this time, the condition will be difficult to reverse, so the timing of rehabilitation training is very important.

If the dementia is severe, he may not recognize his relatives. Although he can walk and eat, he will have some safety issues. He cannot understand the training and has no communication channels. The key is nursing.

In terms of treatment, because drugs can only partially improve overall cognitive function and cannot effectively cure cognitive impairment, so far, the drugs used in clinical practice and approved by the FDA (U.S. Food and Drug Administration) are limited.

One of them is cholinesterase inhibitors, which can mainly improve cognitive function overall. When we look at whether it is effective or not, we usually find that its overall function is improving by using some scales to evaluate.

There is another drug, which is a non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist, which is mainly used for patients with moderate to severe Alzheimer's disease.

These drugs are prescription drugs and must be used under the guidance of a doctor. Do not take them without a doctor's advice. During treatment, you should start with a small dose and gradually adjust it to reach the target dose.

Figure 2 Original copyright image, no permission to reprint

In addition, if the patient has memory impairment, he or she may easily forget to take medicine, so it is also important that his or her caregiver help and remind him or her to take medicine.