Money can’t buy you muscle in old age, saving money is not as good as saving muscle - Beware of sarcopenia in the elderly

There is an old saying that "a thousand gold coins cannot buy thinness in old age". Is there any scientific basis for this saying? Is it a good thing for the elderly to be pale and skinny? The answer is no. The human skeletal muscle has its own growth and aging law. The skeletal muscle mass reaches its peak at around 25 years old. Between 40 and 70 years old, it decreases by 8% every 10 years. At the age of 60, the muscle loss reaches 30%. After the age of 70, it decreases by 15% every 10 years.

As the elderly age, they experience a progressive decrease in skeletal muscle mass, accompanied by a decrease in muscle strength and/or muscle function, and they need to be vigilant about the occurrence of sarcopenia.

1. Definition of Sarcopenia

Sarcopenia originated from Greek and was first proposed by Irwin Rosenberg in 1989. It refers to the aging-related decline in skeletal muscle mass, muscle strength or physical function, which is more common in the elderly. It is also called muscle wasting syndrome, sarcopenia, and sarcopenia.

Sarcopenia is a progressive disease whose core element is the loss of skeletal muscle mass and is characterized by the resulting physical dysfunction.

It can also occur in healthy elderly people who have not lost weight, and it can easily cause bone salt loss, increase basal metabolic rate and body fat in the elderly, and is closely related to the occurrence of chronic diseases such as diabetes, hypertension, osteoporosis, and coronary artery disease.

In addition, it can also lead to gait abnormalities and balance problems, cause body dysfunction, and increase the risk of falls, disability, and death in the elderly, which should be of concern.

Since 2016, the World Health Organization's International Statistical Classification of Diseases and Related Health Problems (ICD) has officially defined sarcopenia as a disease, with the code ICD-10-CM (M62.84). Clinically, primary sarcopenia caused by aging and secondary sarcopenia caused by chronic diseases or decreased mobility are common. This article mainly discusses primary sarcopenia related to aging.

2. Risk factors for sarcopenia

The results of an epidemiological survey on sarcopenia in the Chinese population showed that the prevalence of sarcopenia in the elderly aged ≥60 years was 5.7% to 23.9%. There were obvious differences in the prevalence among the elderly in different regions and between different genders. The prevalence in the eastern region was significantly higher than that in the western region, the prevalence in males was higher than that in females, the prevalence in hospitals and nursing homes was higher than that in the community, and the prevalence in rural areas was significantly higher than that in urban areas.

It is known that many factors are closely related to the occurrence and development of sarcopenia. First, it is closely related to aging. The prevalence rate in men is slightly higher than that in women. As the elderly age, the organ functions of the elderly decline and hormone levels change, which can lead to decreased exercise capacity, loss of muscle mass and muscle strength.

Secondly, sarcopenia is caused by muscle disuse due to long-term immobilization and bed rest, skeletal muscle denervation, severe malnutrition, tumor cachexia, endocrine metabolic diseases, and genetic inheritance. Among them, primary sarcopenia is only related to age, while secondary sarcopenia is mostly related to exercise, nutrition, and disease.

3. Diagnostic process of sarcopenia

The diagnosis of sarcopenia mainly includes the following three aspects: muscle mass assessment, muscle strength assessment and physical function assessment.

First, a preliminary screening was performed on the newly diagnosed patients using the Sarcopenia Five-item Rating Questionnaire (SARC-F) or the Sarcopenia Five-item Rating Questionnaire (SARC-F).

Screening was performed using the SARC-CalF questionnaire. A SARC-F score of ≥4 was considered positive, and a SARC-CalF score of ≥11 was considered positive, and the patient entered the next stage for further evaluation.

Second, the assessment of muscle mass. Dual-energy X-ray absorptiometry (DXA) is the gold standard for measuring muscle mass, and bioelectrical impedance analysis (BIA) is relatively simple and convenient, and is more suitable for extensive screening and diagnosis in communities and hospitals. Muscle mass <7.0kg/m2 for men and <5.4kg/m2 for women measured by DXA is considered to be reduced muscle mass. Muscle mass <7.0kg/m2 for men and <5.7kg/m2 for women measured by BIA is considered to be reduced muscle mass.

Third, assessment of muscle strength. Using a hand dynamometer to measure upper limb grip strength is the preferred indicator for the assessment and diagnosis of sarcopenia. When measuring, measure each hand three times and take the maximum value. Male <28kg and female <18kg are usually the cutoff values ​​for decreased muscle strength. For patients with hand trauma, disability, finger arthritis, etc., a 5-time sit-up test can be used to record the time required to stand up from sitting position 5 times as an alternative method to measure muscle strength.

Fourth, physical function assessment. The 6-minute walking test is the most commonly used assessment method, and the diagnostic threshold is <1.0 m/s.

4. Interventional treatment for sarcopenia

Intervention treatments for sarcopenia include exercise intervention, nutritional support, drug therapy and traditional medical treatment.

First, exercise intervention.

Scientific exercise training for all elderly people aged 60 and above who are diagnosed with sarcopenia and have no contraindications to exercise training can effectively improve muscle mass, muscle strength and walking speed. It is recommended to organically combine warm-up exercises, aerobic training, resistance training, balance training and traditional Chinese sports to effectively improve physical function, increase lean body tissue, and achieve the goal of increasing muscle and reducing fat.

Second, nutritional support.

Malnutrition is an important cause of sarcopenia and the main target of its intervention. All elderly people with sarcopenia and possible sarcopenia should undergo necessary nutritional risk screening and nutritional assessment. A nutritional risk screening NRS2002 score ≥3 points indicates the existence of nutritional risk and the need for clinical nutritional intervention. Oral nutritional supplementation (ONS) for sarcopenic patients with malnutrition can help improve muscle mass and muscle strength in sarcopenic patients. For elderly patients with sarcopenia, if there is no liver or kidney dysfunction, the protein intake is 1.2~1.5g/kg/d, and high-quality protein such as meat, eggs, milk and beans accounts for more than half.

Third, drug treatment.

Currently, drugs for the treatment of sarcopenia are still in the research and development stage and still need more clinical application evidence. Studies have shown that vitamin D and testosterone can improve muscle mass, muscle strength and/or physical performance, but there is no evidence to recommend other drug interventions as effective.

Fourth, traditional medicine treatment.

Traditional Chinese sports, such as 24-style simplified Tai Chi, Ba Duan Jin and Wu Qin Xi, can improve cardiopulmonary function, enhance muscle endurance and reduce the risk of falls in the elderly. According to the clinical symptoms of patients, traditional Chinese medicine believes that sarcopenia should be classified as a type of "paralysis syndrome" in traditional Chinese medicine. "The spleen governs muscles" and "Yangming meridian is the only meridian for paralysis" are believed to be the cause of sarcopenia due to spleen deficiency leading to indigestion and insufficient nutrition intake causing muscle movement. The basic principle of treating the disease is to tonify the spleen and replenish the loss. Commonly used prescriptions are Sijunzi Decoction, Bazhen Decoction and Buzhong Yiqi Decoction with modifications.

Money can't buy you meat in old age, so saving money is worse than saving muscle. Muscle means strength and symbolizes stronger vitality! Each of us should "save muscle to protect health" from now on, adhere to scientific diet and nutrition, professional exercise, and effectively improve muscle quality, strength and body function.

In summary, exercise intervention is the basis and nutritional support is the key to the treatment of sarcopenia in the elderly.

If you want to know more professional exercise and nutritional prescriptions for sarcopenia, please stay tuned for the next article.

References:

[1] Guan Wei. Sarcopenia and nutritional intervention[J]. Chinese Journal of Clinical Nutrition, 2012, 20(3):162-165.

[2] Liu Juan. Expert consensus on the diagnosis and treatment of sarcopenia in the elderly in China (2021)[J]. 2021.

[3] Yu Pulin. Chinese expert consensus on core information for preventing sarcopenia in the elderly (2021)[J]. Chinese Journal of Geriatrics, 2021, 40(8):2.

[4] Cui Hua. Chinese expert consensus on prevention and control of sarcopenia in the elderly (2023)[J]. Chinese Journal of Geriatrics, 2023, 42(2)

Text: Ren Fanghua, Sports Rehabilitation Department

Guiding expert: Chief Physician Wu Liang