There are several major causes of cognitive impairment in the elderly! What tests can be done to identify the cause?

Author: Wang Huali, Professor of Peking University Sixth Hospital

Reviewer: Hu Wenli, Chief Physician, Beijing Chaoyang Hospital, Capital Medical University

Cognitive functions generally include memory, attention, language ability, reasoning ability, execution and judgment ability. The decline of cognitive function due to abnormal brain structure or function is called cognitive impairment.

Cognitive impairment in the elderly generally includes two states: mild cognitive impairment and severe cognitive impairment. Severe cognitive impairment is what was usually called dementia in the past, with the main characteristics of cognitive impairment, emotional and behavioral problems, and some people will have serious declines in social ability, living ability, and self-care ability.

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1. What are the causes of cognitive impairment in the elderly?

Cognitive impairment is not a single disease, but a collection of syndromes with various and complex causes that can be roughly classified into several major categories.

For the elderly, the primary cause is degenerative changes in the nervous system, including Alzheimer's disease, frontotemporal dementia, Lewy body dementia and dementia associated with Parkinson's disease, all of which are common neurodegenerative diseases causing dementia.

Secondly, cerebrovascular disease is also an important cause. For example, cerebral infarction and cerebral hemorrhage may be accompanied by cognitive impairment, which is classified as vascular causes. In addition, there are cases where degenerative changes coexist with vascular diseases, that is, mixed cognitive impairment.

In addition, severe malnutrition, vitamin deficiency, encephalitis, HIV infection and other factors can also cause cognitive decline. It is worth noting that improper use of drugs, drug interactions and toxicity may also become potential causes of cognitive impairment. Endocrine dysfunction, such as hypothyroidism, may also lead to impaired cognitive function.

Vascular cognitive impairment is easy to detect due to its close association with cerebral infarction and cerebral hemorrhage, and its development is relatively rapid. In contrast, cognitive impairment caused by neurodegenerative diseases is more hidden, early symptoms are often ignored, and the course of the disease is long. It is often not taken seriously until patients lose their ability to take care of themselves, have mood swings, and have difficulty communicating. At this time, the best time for early diagnosis and treatment has been missed.

Memory loss, weakened executive function, decreased language ability, disorientation, and changes in mood and behavior are all early signs of cognitive impairment. If two or more types of cognitive impairment occur, it supports the clinical diagnosis. In order to make a clear diagnosis, a detailed evaluation with the help of a scale is required, and the specific cause of cognitive impairment is explored through detailed examinations so that scientific treatment can be implemented as soon as possible.

2. What examinations should be done to clarify the causes of cognitive impairment in the elderly?

For patients with cognitive impairment, the cause of the disease should not be easily concluded. It is recommended to conduct appropriate examinations to determine the specific cause so as to achieve targeted treatment.

For example, blood tests can screen for vitamin deficiencies or viral infections, including HIV and syphilis. Blood tests are also used to evaluate liver and kidney function, as severe illness can also lead to cognitive decline.

In addition, magnetic resonance imaging is recommended to observe whether there is atrophy in the brain and its specific location. With the in-depth understanding of Alzheimer's disease and other common neurodegenerative diseases, molecular imaging diagnostic techniques, such as positron emission tomography, have also been applied to brain molecular imaging. Cerebrospinal fluid examination can also be used to detect changes in the levels of substances related to pathological changes to assist clinical diagnosis.

A high level of clinical diagnostic accuracy can be achieved by combining cognitive function assessment, imaging, and hematological examinations. In the future, with the further development of molecular imaging technology and molecular biomarker detection technology, it is expected that potential lesions can be identified through early marker screening and suspected cases can be continuously monitored. Once symptoms appear, timely intervention and treatment can be carried out. Even if no symptoms appear, long-term follow-up should be carried out to achieve earlier detection and more treatment opportunities based on pathological evidence and symptom monitoring.

3. What aspects does the treatment of cognitive impairment in the elderly include?

After being diagnosed with cognitive impairment, professional doctors will develop a comprehensive treatment plan that strictly covers both drug and non-drug aspects.

Drug treatment is mainly symptomatic. Commonly used drugs include two categories: one is cholinesterase inhibitors, which improve symptoms by inhibiting the decomposition of acetylcholine in the brain and enhancing the function of neurotransmitters; the other is glutamate receptor antagonists, namely NMDA receptor antagonists. Since glutamate, as an excitatory neurotransmitter, is toxic to nerve cells when overactive, antagonizing its effects helps protect nerve cells.

In addition, existing studies believe that abnormal deposition of amyloid protein is one of the pathological bases of Alzheimer's disease. Clinical trials have found that amyloid protein monoclonal antibodies can effectively reduce the level of amyloid protein deposition in the brain, and can to a certain extent slow down the rate of disease decline in patients with mild cognitive impairment and early Alzheimer's disease, and delay the progression of the disease.

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Non-drug interventions cover two levels: patient-oriented and caregiver-oriented.

The intervention measures for patients are diverse and comprehensive, including psychological support, cognitive rehabilitation training, participation in educational activities, physical exercise, music therapy and exercise therapy, etc., aiming to promote the recovery of patients' psychological and cognitive functions through daily communication, interactive games, etc. In addition, advanced sensory stimulation therapy can be used, using professional equipment to provide multi-sensory stimulation such as touch, hearing, and vision, as well as innovative methods such as pet therapy and intelligent robot companionship to enrich patients' life experience.

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Intervention for caregivers is equally important, focusing on their mental health and social support. By organizing caregiver exchanges and providing professional psychological counseling, we help caregivers release stress and improve their care efficiency and ability. At the same time, through training and empowerment, caregivers can master more care knowledge and skills, enhance their sense of value and accomplishment in the care process, and thus respond to care challenges more actively and effectively.