Sarcopenia

What is Sarcopenia?

Sarcopenia is a disease that often affects older people, causing a gradual decrease in muscle mass and strength. It is defined by three main characteristics: reduced muscle strength, lower quantity or quality of muscle, and decreased physical performance. This loss of muscle can affect daily activities and often signals potentially negative outcomes, such as complications, illnesses, or even death after major surgeries.

Furthermore, sarcopenia is closely linked to a higher chance of falls and an increased risk of fractures. A decrease in muscle mass or function, the key factors in identifying sarcopenia, can also lead to a loss of independence for patients over 90 years old. Sarcopenia has gained significant attention in recent medical research and now has its own specific code in the International Classification of Disease (ICD) 10, which helps in differentiating it from other diseases that also involve muscle loss.

What Causes Sarcopenia?

Sarcopenia, or the loss of muscle strength due to aging, has several causes. Some are due to natural aging processes that we don’t fully understand, and others are due to things like decreased muscle fiber size and number, lack of physical activity, obesity, insulin resistance, low androgen and growth hormone levels, inadequate protein intake, and a reduced response to protein intake or resistance exercise.

Chronic diseases that negatively impact the muscles and physical activity are also linked to sarcopenia. These include chronic obstructive pulmonary disease (COPD, a type of lung disease), chronic heart failure, chronic kidney disease, diabetes, HIV, and cancer.

These diseases may contribute to sarcopenia in a few ways. They could directly affect muscle function, slow down physical activity, or cause you to eat less. However, it’s important to note that in the case of cancer, doctors often look at cachexia (a severe loss of weight, muscle atrophy, fatigue, weakness, and loss of appetite) as an indicator of tissue loss more often than sarcopenia, even though both conditions have similar symptoms.

Risk Factors and Frequency for Sarcopenia

Sarcopenia is a condition that mainly shows up in elderly people, affecting both men and women equally. The frequency of this condition varies greatly, depending on how it’s diagnosed and who is being studied, but it’s estimated to affect between 5-13% of those aged 60 and above, and between 11-50% of those aged 80 and above. When looking at people over 60 worldwide, about 10% are estimated to have sarcopenia. Research on whether certain ethnicities are more prone to sarcopenia has so far been inconsistent.

• Sarcopenia occurs mostly in people aged 60 and above, affecting both males and females equally.
• 5-13% of people aged 60 and above are estimated to have sarcopenia.
• Between 11-50% of people aged 80 and above are believed to have the condition.
• Worldwide, 10% of those over 60 are estimated to suffer from sarcopenia.
• Data on the link between sarcopenia and ethnicity has been inconsistent across studies.
• The prevalence of sarcopenia is higher in people with chronic diseases like COPD, CHF, CKD, DM, HIV, and cancer.

Signs and Symptoms of Sarcopenia

Sarcopenia is a condition involving a decrease in muscle strength, bulk, and performance. It commonly affects older people who lead inactive lifestyles and may suffer from other health problems. As a result, their ability to function and quality of life may decline. The signs of sarcopenia develop gradually and include a loss of muscle mass and strength, along with reduced ability to perform daily tasks.

Testing for Sarcopenia

The process of evaluating a patient for muscle weakening due to aging (sarcopenia) involves several steps, from simple questionnaires to complex imaging studies to measure muscle mass. There exists a “find-assess-confirm-severity” or F-A-C-S approach, proposed by the European working group on sarcopenia in older people 2 (EWGSOP2), to help healthcare providers to identify and manage this condition.

The SARC-F questionnaire is a quick screening tool used to identify potential sarcopenia patients. The questionnaire looks at strength, ability to walk, get up from a chair, climb stairs, and occurrence of falls. Each item is rated between 0 and 2, with a maximum total score of 10. A score of 4 or higher suggests that your doctor may need to evaluate you further.

Muscle strength can first be assessed through handgrip tests and chair stand tests. The handgrip test measures the strength of your hand and can indicate overall muscle strength. If your handgrip is weaker than normal, this could be a sign of sarcopenia, and it can also predict other poor health outcomes. The chair stand test measures how many times you can stand and sit from a chair without using your arms within 30 seconds. This gives an indication of the strength in your legs’ muscles.

To confirm a sarcopenia diagnosis, tools that measure muscle quantity and quality are used. These tools are used to calculate total body muscle mass, appendicular skeletal muscle mass (in the arms and legs), or the cross-sectional area of a specific muscle. MRI and CT scans are the most accurate but are expensive and limited in availability. Dual-energy X-ray absorptiometry (DEXA) and bioelectrical impedance analysis (BIA) offer a more convenient and readily available option to confirm sarcopenia.

After sarcopenia is confirmed, the next task is to determine how severe it is. This is done by measuring physical performance. Tests such as the gait speed test, short physical performance battery (SPPB), timed-up and go test (TUG), and the 400-meter walk test are used. These tests measure walking speed, ability to stand from sitting, maintaining balance, and the time taken to walk a certain distance. Difficulty in these tasks or slower than normal times suggest a more severe case of sarcopenia.

Treatment Options for Sarcopenia

Engaging in physical activity, especially strength-building exercises, can help reduce muscle loss and boost strength in sarcopenia. This means it can help both to prevent and manage the condition. Eating more protein, either through your regular diet or supplements, can also help prevent and manage sarcopenia.

It’s recommended that you consume 20-35 grams of protein per meal. This amount provides plenty of amino acids, the building blocks of proteins, which are necessary to maximize Muscle Protein Synthesis (MPS). This helps in reducing muscle loss as you age. Additionally, patients with sarcopenia should aim to consume around 1.0 – 1.2 grams of protein per kilogram of their body weight per day.

The most noticeable improvements are seen when strength-building exercises are combined with a high-protein diet. These two work together, enhancing each other’s effectiveness.

What else can Sarcopenia be?

Sarcopenia, which is the loss of muscle mass and function, can often co-exist with the following conditions and the symptoms may overlap, making an accurate diagnosis challenging:

• Frailty: Both sarcopenia and frailty share several common symptoms like decreased muscle strength and function. However, frailty impacts more systems in the body while sarcopenia primarily impacts the musculoskeletal system. These two conditions often co-exist in elderly patients.
• Malnutrition: Just like sarcopenia, malnutrition also results in low muscle mass. However, sarcopenia often involves additional function loss. Patients with malnutrition may have reduced fat due to low calorie consumption, which is not commonly seen in sarcopenia. Tests measuring strength and performance may help determine whether malnutrition is a factor.
• Cachexia: Cachexia is a complex condition that results in severe weight loss and muscle wastage. It’s usually associated with severe diseases like HIV, cancer, and end-stage organ failure. While a patient can have both cachexia and sarcopenia, a person with severe muscle-wasting diseases is more likely to have cachexia. The Glasgow prognostic score may be used to differentiate between these two conditions.
• Osteoarthritis of the hand: Osteoarthritis of the hand can result in a false positive test when measuring grip strength, which is a test often used to diagnose sarcopenia. In such cases, physicians can measure the isometric torque of the lower limb to accurately determine the presence or absence of sarcopenia.

Careful analysis and testing are needed to correctly diagnose sarcopenia, especially when other co-existing conditions may be present.

What to expect with Sarcopenia

The outlook for patients with sarcopenia, a condition marked by loss of muscle mass and strength, depends on various factors like age, other health conditions, and incidents of falls or fractures. Also, sarcopenia patients who undergo surgeries are likely to have less successful results compared to those without the condition. This can mean a higher risk of complications after surgery, more falls, longer hospital stays, more fractures, and greater overall sickness and risk of death.

However, it’s important to mention that how sarcopenia progresses by itself isn’t fully known or extensively researched. That being said, there’s reliable evidence that shows sarcopenia can signal a poor outlook in a variety of health conditions and surgical procedures.

Possible Complications When Diagnosed with Sarcopenia

According to a study done by Yeung and colleagues, which looked at the data from over 45,000 patients from 33 different studies, the condition of sarcopenia (muscle loss due to aging) significantly increases the risk of falls and fractures in older adults. Additionally, the same study found that sarcopenia also raises the chances of getting a hospital-acquired infection for this age group.

Regarding medical complications, sarcopenia has been linked with a higher death rate in patients with severe kidney disease, pancreatic cancer, and chronic heart failure. Also, patients with sarcopenia going through chemotherapy for kidney, liver, and breast cancers are more likely to experience severe complications that limit the dose of chemotherapy they can handle.

In terms of surgery, sarcopenia has been associated with an increased risk of complications after general surgeries and liver transplants. Furthermore, sarcopenia has been linked to a higher death rate in patients undergoing general surgeries and colorectal surgeries.

Health Risks of Sarcopenia:

• Falls and Fractures in elderly
• Hospital-acquired infections in elderly
• Higher death rates with end-stage kidney disease
• Increased mortality in pancreatic cancer patients
• Increased death rates among chronic heart failure patients
• Higher chemotherapy complications in kidney, liver, and breast cancers
• Increased complications after surgery
• Higher death rate post surgeries and colorectal surgeries

Preventing Sarcopenia

It’s crucial for people to take care of their health by adhering to good hygiene practices and going for regular health check-ups. They should also communicate any changes they observe in their health, weight, physical appearance, or body performance to their healthcare provider. Alongside this, they should also be informed about the risk of a condition known as sarcopenia, which affects muscle strength and mass, especially as a person gets older. This condition poses a particular risk to those dealing with various health issues concurrently.

The most effective approach to addressing the challenges sarcopenia presents in older individuals is through prevention. Taking steps to prevent, manage, and treat sarcopenia can be most effective by keeping physically active and consuming enough protein. In particular, individuals should understand the recommended amount of protein intake both daily and per meal. It’s also beneficial for patients to understand the advantages of resistance training, which incorporates exercises that make your muscles work against a force or weight. Combining this with the above-mentioned measures can help to either prevent or manage sarcopenia effectively.