Sarcopenia, a disease of the elderly you should know about

With the extension of the average human life span and the acceleration of the aging process of the global population, the incidence of geriatric diseases has increased year by year. Muscle loss is an inevitable consequence of the aging process, and it is also the part of the body that loses the most mass during aging. The loss of muscle is accompanied by the loss of function. Sarcopenia increases the risk of falls and fractures, has a significant impact on the health and quality of life of middle-aged and elderly people, and increases the burden on individuals, families, and society. At the same time, with the rapid development of geriatric medicine, the quality of life of the elderly has attracted much attention. Sarcopenia has been a research hotspot in geriatric diseases in recent years. Therefore, early screening, early prevention, and early intervention of sarcopenia are particularly necessary.

1. What is sarcopenia?

Sarcopenia is a syndrome of progressive skeletal muscle loss, decreased muscle strength and/or muscle function associated with aging, which causes a series of adverse consequences. The occurrence of sarcopenia can lead to functional loss in the elderly. The occurrence and development of the disease are related to many factors. In most cases, the incidence of sarcopenia is mainly primary sarcopenia related to age. Current studies have shown that the incidence of sarcopenia in the elderly population is about 8% to 40%, and its incidence gradually increases with age. Data show that at the age of 50 to 70, the rate of muscle loss will reach 8% every 10 years, and after the age of 70, it will decrease at a rate of 15%.

Human muscle reserves mainly start from birth and reach a peak at around 30 years old. After 30 years old, it decreases at a rate of 1% per year; after 50 years old, the rate of decline exceeds 1.5% per year; the rate of muscle loss is faster for people over 70 years old. Sarcopenia is preventable. Early adoption of a reasonable lifestyle and intervention can effectively prevent its development. In old age, we should pay attention to balanced nutrition and reasonable exercise. In addition to aerobic exercise, we should also increase resistance exercise to keep the muscles in a good functional state.

2. Symptoms of sarcopenia

Sarcopenia is characterized by a decrease in skeletal muscle mass and the production of a large amount of fat within the muscles, which in turn affects muscle strength and function. Since the body's balance ability is affected by the strength of the lower limb muscles, a decrease in lower limb muscle strength will directly affect the balance function, leading to an increase in the frequency of falls in the elderly, resulting in adverse consequences such as disability in the elderly, and seriously affecting the quality of life of the elderly.

Sarcopenia currently has no specific clinical manifestations. Patients' symptoms include weakness, muscle weakness, slow walking speed, easy falls, etc. Its etiology and pathogenesis are very complex. Lack of physical activity and insufficient protein intake are considered to be the main factors leading to sarcopenia.

3. Diagnosis of sarcopenia

For the diagnosis of patients with sarcopenia, the 2018 European Elderly Sarcopenia Working Group meeting proposed the 2018EWGSOP2 recommendation, which updated the diagnostic process for patients with sarcopenia: case discovery-assessment-confirmation-severity. First, the SACF-F scale is used to identify suspected patients, then the sit-up test and grip strength are used for assessment, and then muscle mass measurement is used to diagnose whether it is sarcopenia. People with sarcopenia use physical fitness tests to determine its severity.

3.1 SACF-F Scale

The "SARC-F" sarcopenia assessment scale and supplementary questionnaire include five items: strength, assisted walking, standing up, climbing stairs, and falling. When the "SARC-F" scale score is ≥4 points, the screening is positive and suspected cases can be preliminarily detected.

3.2 Calf circumference

The maximum circumference of the calf was measured bilaterally using a non-elastic band. The Asian Working Group for Sarcopenia (AWGS) recommended that the calf circumference be used to diagnose males.