Sarcopenia: types, causes, diagnosis and impact (2025)

Sarcopenia is characterised by low muscle strength, low muscle quality and low physical performance.This is a Self-assessment article and comes witha self-assessment test

Nursing Times Self-assessment articles offer bitesize CPD and are accompanied by multiple-choice assessments with feedback. Test yourself on this article or click here to choose other subjects from the Self-assessment archive.

Abstract

Sarcopenia is the gradual loss of skeletal muscle mass and strength, and is associated with age-related deterioration. There are multiple diagnostic tests, which have variations in muscle mass cut-off points. This article – the first in a series of two – explains the different types of sarcopenia, why it develops, how it affects patients and the importance of diagnosis.

Citation: Nazarko L (2024) Sarcopenia: types, causes, diagnosis and impact. Nursing Times [online]; 120: 12.

Author: Linda Nazarko is specialist frailty nurse, Sutton Health and Care, Epsom and St Helier University Hospitals NHS Trust.

  • This article has been double-blind peer reviewed
  • Scroll down to read the article or download a print-friendly PDF here (if the PDF fails to fully download please try again using a different browser)
  • Assess your knowledge and gain CPD evidence by taking the Nursing Times Self-assessment test
  • Read part 2 of this series here

Introduction

In 1989, Irwin Rosenberg coined the term ‘sarcopenia’ to describe the loss of muscle mass; the word is derived from the Greek sarco (flesh or muscle) and penia (loss) (Rosenberg, 1997). He later stressed the need for research to determine whether sarcopenia is an age-related loss of muscle mass and function, a disease, or a typical part of the ageing process (Rosenberg, 1997).

The European Working Group on Sarcopenia in Older People (EWGSOP) published a definition of sarcopenia in 2010. This was revised in 2018 by the EWGSOP2, which listed three criteria to identify possible sarcopenia:

  • Low muscle strength;
  • Low muscle quantity or quality;
  • Low physical performance (Cruz-Jentoft et al, 2019).

Low muscle strength is the “key characteristic” of sarcopenia; the presence of all three features indicates severe sarcopenia (Cruz-Jentoft et al, 2019).

Sarcopenia is a syndrome characterised by progressive and generalised loss of skeletal muscle mass and strength. It is associated with physical disability, poor quality of life and increased risk of death (Cruz-Jentoft et al, 2019). The NHS spends an estimated £2.5bn per year managing the consequences of sarcopenia (Marshall et al, 2020).

It is difficult to determine the prevalence of sarcopenia, because there is no single diagnostic test. The condition is assessed differently worldwide, due to inconsistencies in the way the following factors are accounted for:

  • Diagnostic classifications;
  • Cut-off points;
  • Variations in muscle mass due to ethnicity and sex (Petermann-Rocha et al, 2021).

Even when the same criteria are used, if different tools are used to measure them, they can give different results (Kilgour et al, 2020).

In a literature review of 109 articles, Mayhew et al (2019) identified that eight definitions of sarcopenia were used; for this reason, the articles’ estimates of the prevalence of sarcopenia in community-dwelling older people varied from 10% to 40%. Additionally, a study by Ramirez et al (2022) identified that using the EWGSOP2’s guidelines from 2018 led to an underestimation of the prevalence of sarcopenia compared with rates when using the EWGSOP’s 2010 guidelines.

Sarcopenia is more common in older people, and a study by Yazar and Yazar (2019) identified its prevalence among adults aged >80years as 37%. Using Yazar and Yazar’s (2019) results and population data from the Office for National Statistics (2022), we can conservatively estimate that >5million people in the UK have sarcopenia (Fig1); however, this gives no indication of the severity of the condition.

Sarcopenia: types, causes, diagnosis and impact (1)

Types and causes of sarcopenia

Primary sarcopenia is related to ageing, which affects muscle function and strength. Aerobic capacity – a measure of the ability of the heart and lungs to supply oxygen to the muscles – decreases by ~40% between the ages of 25 and 80 years (Roman et al, 2016). Adults lose up to 8% of muscle strength per decade after the age of 30 years and, from the age of 65, this falls even more rapidly (Cleveland Clinic, 2022).

One reason for this is that testosterone, an anabolic steroid that helps to build and maintain muscle mass, falls by around 1-2% a year in men from the age of 50 years onwards (Shigehara et al, 2022). The accelerated decline of muscle mass, strength and physical performance is sarcopenia (Wan et al, 2023).

According to the EWGSOP2’s guidelines, sarcopenia is considered secondary when there are causes “other than (or in addition to) ageing” (Cruz-Jentoft et al, 2019). There are many causes of sarcopenia; these are shown in Fig 2.

Sarcopenia: types, causes, diagnosis and impact (2)

Around 30% of older people admitted to hospitals decline functionally; this can have long-lasting effects, including sarcopenia (Chen et al, 2022). One study of older people found that, six months after discharge, 24% could still not walk 0.25 miles and 45% were still unable to drive (Chen et al, 2022).

Sarcopenia can also occur because of poor nutrition. This can be due to:

  • Lack of access to food;
  • Limited ability to cook or eat;
  • Anorexia;
  • Malabsorption (Yuan and Larsson, 2023; Roberts et al, 2019).

Suboptimal nutrition accelerates age-related loss of muscle mass and strength (Marshall et al, 2020). Although sarcopenia is associated with weight loss, some adults with sarcopenia may be obese (Cruz-Jentoft et al, 2019).

Age-related endocrine changes are believed to be of particular importance in the development of sarcopenia. There is reduced secretion of growth hormone, insulin-like growth factor 1, testosterone, oestradiol, vitamin D, thyroid hormones and dehydroepiandrosterone; this leads to a reduction in muscle mass and decreased function. There is also decreased insulin sensitivity, which – combined with reduced hormone levels – affects the growth and repair of muscles (Priego et al, 2021).

Conversely, levels of cortisol and angiotensin II increase with age; this can accelerate the rate of age-induced muscle wasting (Priego et al, 2021).

Adipose tissue secretes molecules called adipokines. Adipokines are cytokines – small proteins that regulate inflammation, metabolism, immunity and other physiological processes (Mukund and Subramaniam, 2020). Cytokines – such as interleukin, tumour necrosis factor and C-reactive protein – are associated with reduced muscle function (Wang et al, 2017). Cytokines are thought to induce sarcopenia by:

  • Activating the ubiquitin proteasome pathway, a process of cellular repair, which decreases insulin-like growth factor production;
  • Inducing insulin resistance (Mukund and Subramaniam, 2020).

Acute and chronic sarcopenia

Sarcopenia that has lasted for less than six months is defined as acute. It is typically associated with an acute illness or injury, such as that illustrated in the case study in Box 1.

Sarcopenia that has lasted for six months or longer is defined as chronic. This is usually related to chronic and progressive conditions, such as chronic obstructive pulmonary disease, and increases the risk of mortality (Cruz-Jentoft et al, 2019).

Box 1. Case study

Margaret Morrison* is an 82-year-old widow who lives alone. Mrs Morrison caught a nasty dose of flu and then developed a chest infection. She did not seek medical attention as she believed she would get better naturally. When Mrs Morrison’s daughter came to see her, she found her mother was breathless and acutely unwell. She took her straight to the emergency department, where she was diagnosed with pneumonia. Mrs Morrison was admitted to hospital and treated with intravenous antibiotics. Although not clinically required, she was catheterised and did not get out of bed for two weeks. She became constipated, ate little and lost weight.

After two weeks, Mrs Morrison was very weak, felt dizzy when she stood up and had developed sarcopenia. She required extensive rehabilitation in a community hospital before she could return home, and then required further support at home for six months. She is now independent again.

*The patient’s name has been changed.

The aim of categorising sarcopenia as acute or chronic is to encourage the regular monitoring of patients. This is to facilitate early intervention to treat sarcopenia or delay its progression (Cruz-Jentoft et al, 2019).

Diagnosing sarcopenia

Sarcopenia is a disease that has been recognised only fairly recently. Patients who have it may be seen:

  • On an orthopaedic ward;
  • On a medical ward;
  • On an older person’s ward;
  • By a GP;
  • In a community service, such as a falls clinic;
  • As part of a specialist nurse’s caseload.

This means that clinicians may not be fully aware of sarcopenia or how it is diagnosed. The pathway recommended by EWGSOP2 is that clinicians find cases, assess, confirm diagnosis and determine severity (FACS) (Cruz-Jentoft et al, 2019).

Sarcopenia is overlooked and undertreated in clinical practice. Further testing for sarcopenia is recommended when someone reports its signs or symptoms, such as:

  • Falling;
  • Feeling weak;
  • Having a slow walking speed;
  • Having difficulty rising from a chair;
  • Experiencing weight loss;
  • Experiencing muscle wasting (Cruz-Jentoft et al, 2019).

One screening tool is the strength, assistance with walking, rising from a chair, climbing stairs and falls (SARC-F) questionnaire. This asks the individual to rate their ability to perform each of the five components on a scale of 0-2; a total score of ≥4 is predictive of sarcopenia and poor outcome (Malmstrom et al, 2015).

The SARC-F questionnaire is not suitable for everyone, and alternative screening tests may be needed if literacy or cognition is a problem (Malmstrom et al, 2015). As an example, the Ishii screening tool estimates the probability of sarcopenia by creating a score based on a patient’s age, grip strength and calf circumference (Cruz-Jentoft et al, 2019).

If sarcopenia is suspected or the SARC-F questionnaire suggests a patient has sarcopenia, the patient’s muscle strength should be assessed (Cruz-Jentoft et al, 2019). There are two components to this:

  • Grip assessment;
  • The sit-to-stand test.

Links to further resources about both components are outlined in Box 2.

Grip strength is assessed using a handheld dynamometer; the result is interpreted using norms based on gender and age (Cooper et al, 2021).

The sit-to-stand test is carried out using a chair that has no arms and a seat height of 43cm. The chair, with rubber tips on the legs, is placed against a wall to prevent it from moving. The patient sits in the middle of the chair with their back straight.

Their feet must be on the floor, approximately shoulder-width apart and slightly behind the knees; one foot should be slightly in front of the other to help maintain balance. Their arms are crossed at the elbows and held against their chest.

The patient watches a demonstration and practises a few times. They are then instructed to complete as many full stands as possible within 30 seconds, fully sitting between each one. The person conducting the test silently counts the number of correctly completed stands; if the patient is more than halfway up at the end of the 30 seconds, this counts as a full stand.

Their score is the total number of stands within 30 seconds although, if they need to use their arms to stand, they are scored 0. Scores typically range between 0 for those who are unable to complete the test and 20 for fitter individuals (Mehmet et al, 2020).

Diagnosis can be confirmed with a dual-energy X-ray absorptiometry (DEXA) scan, CT scan, MRI or bioelectrical impedance analysis (BIA); DEXA is “the procedure of choice for routine clinical assessment” (Beaudart et al, 2016).

However, parameters vary according to age, gender and ethnicity, and are not yet well established (Beaudart et al, 2016). The method of determining muscle strength should be based on individual factors, including disability, mobility and how acceptable a certain method is to the patient (Yamada et al, 2017).

DEXA is widely available and can determine muscle quantity non-invasively. Muscle mass is related to body size and there are ways to take account of this; however, further work is needed to develop a consensus on methods of adjustment and use with a range of ethnicities, as current sarcopenia guidance is based on European populations (Cruz-Jentoft et al, 2019).

BIA can be used to estimate muscle mass. BIA equipment does not measure muscle mass directly but, instead, estimates it based on whole-body electrical conductivity. BIA is inexpensive, and the equipment necessary is easy to use and portable. Measurements used relate to older Europeans; further work is required for other populations, who may have differing levels of muscle mass (Cruz-Jentoft et al, 2019).

Calf circumference can predict performance and survival in older people, and may be used as a proxy measure of sarcopenia in certain circumstances (Cruz-Jentoft et al, 2019).

“People with sarcopenia may struggle with activities of daily living and need help with personal care”

Dietary assessment is also essential, because poor nutrition can cause and exacerbate sarcopenia (Cruz-Jentoft et al, 2019). The National Institute for Health and Care Excellence (NICE) (2017) requires care providers to screen for the risk of malnutrition using a validated screening tool, such as the Malnutrition Universal Screening Tool.

Typically, height, weight and body mass index are checked, and a screening test is carried out. If there are concerns about weight loss or if the individual is not eating, a detailed assessment should be carried out (NICE, 2017).

Patients who are poorly nourished may need to be assessed and treated by a dietician (NICE, 2017). People with sarcopenia need an optimal intake of protein and vitaminD, which may necessitate nutritional supplements (Patel, 2023).

If they have swallowing difficulties, an assessment by a speech and language therapist is required. They will also need to have a medication review, as they may be unable to swallow certain prescribed medicines, and some can impair swallowing (Philpott et al, 2017).

Impact of sarcopenia

Healthy ageing means remaining physically and mentally well – for example, being active, independent and able to socialise. Sarcopenia can have an enormous effect on quality of life; this can be temporary or permanent (Mijnarends et al, 2018).

There are many impacts of sarcopenia, which are outlined in Fig 3. Physically, it causes reduced stamina, impaired mobility, and an increased risk of falls and fractures (Yeung et al, 2019). It can also lead to depression and impaired cognition (Chen et al, 2022). People with sarcopenia may struggle with activities of daily living and need help with personal care (Brugliera et al, 2023). They may enter a downward spiral, become more dependent and then need long-term care (Chen et al, 2022). Xu et al (2021) identified that, especially when accompanied by impaired mobility, sarcopenia is associated with increased one-year mortality.

Sarcopenia: types, causes, diagnosis and impact (3)

As sarcopenia can have a devastating effect on a person’s quality of life and increase their risk of death, clinicians must be aware of the condition and not assume that low muscle strength and impaired ability and mobility are simply a part of ageing. In hospital and primary care settings, clinicians need to consider sarcopenia when a person has a chronic progressive condition, a history of falls, accelerated physical decline and/or impaired nutrition.

Our knowledge of sarcopenia is growing, and we are increasingly aware that interventions can prevent and manage the condition, thereby reducing its impact. These interventions can be very simple – for example, in the case study in Box 1, the patient might have eaten more if she was enabled to sit in a chair, and deconditioning and muscle loss would have been reduced.

There was no clinical indication for her urinary catheter, and having it meant she did not need to get up and walk to the toilet; therefore, she lost more muscle. Additionally, many hospital wards do not have day rooms, which results in there being little incentive for patients to move around and socialise.

People are living longer, but those longer lives are often marred by activity restriction resulting from a long-lasting physical or mental health condition. The average woman in the UK experiences 22years of disability, and the average man 16years (Nazarko, 2022); therefore, the NHS needs to change from being primarily a disease-management system. Its primary function needs to be promoting health and wellbeing, and disease management needs to be its secondary purpose.

Conclusion

Sarcopenia, the gradual loss of skeletal muscle mass and strength, is associated with age-related deterioration.

There is no single diagnostic test for it, and clinicians need to understand the different types of sarcopenia, as well as its causes and impacts. Diagnosis is essential to improve patients’ quality of life and reduce their risk of mortality.

  • The second part of this series will examine the prevention, treatment and management of sarcopenia

Key points

  • Sarcopenia is characterised by low muscle strength and quality, and low physical performance
  • Primary sarcopenia is related to ageing, whereas secondary sarcopenia occurs with another condition
  • Different diagnostic tools can provide differing results
  • Dietary assessment is essential, because poor nutrition can both cause and exacerbate sarcopenia
  • Sarcopenia has physical, mental and cognitive impacts, including increased mortality

Sarcopenia: types, causes, diagnosis and impact (4)

  • Test your knowledge with Nursing Times Self-assessment after reading this article. If you score 80% or more, you will receive a personalised certificate that you can download and store in your Nursing Times Portfolio as CPD or revalidation evidence.
  • Take the Nursing Times Self-assessment for this article

References

Bauer J et al (2019) Sarcopenia: a time for action. An SCWD position paper. Journal of Cachexia, Sarcopenia and Muscle; 10: 5, 956-961.

Beaudart C et al (2016) Sarcopenia in daily practice: assessment and management. BMC Geriatrics; 16: 170.

Brugliera L et al (2023) Prevalence of sarcopenia in older patients in rehabilitation wards. Journal of Personalized Medicine; 13: 6, 960.

Chen Y et al (2022) Hospital-associated deconditioning: not only physical, but also cognitive. International Journal of Geriatric Psychiatry; 37: 3, 1-13.

Cleveland Clinic (2022) Sarcopenia. my.cleveland clinic.org, 6 March (accessed 6 November 2024).

Cooper R et al (2021) The impact of variation in the device used to measure grip strength on the identification of low muscle strength: findings from a randomised cross-over study. Journal of Frailty, Sarcopenia and Falls; 6: 4, 225-230.

Cruz-Jentoft AJ et al (2019) Sarcopenia: revised European consensus on definition and diagnosis. Age and Ageing; 48: 1, 16-31.

Holdoway A, Ashworth A (2021) Sarcopenia: Loss of Muscle Mass. The Malnutrition Pathway.

Kilgour AHM et al (2020) Prevalence of sarcopenia in a longitudinal UK cohort study using EWGSOP2 criteria varies widely depending on which measures of muscle strength and performance are used. Age and Ageing; 49: S1, i22-i23.

Malmstrom TK et al (2015) SARC-F: a symptom score to predict persons with sarcopenia at risk for poor functional outcomes. Journal of Cachexia, Sarcopenia and Muscle; 7: 1, 28-36.

Marshall RN et al (2020) Nutritional strategies to offset disuse-induced skeletal muscle atrophy and anabolic resistance in older adults: from whole-foods to isolated ingredients. Nutrients; 12: 5, 1533.

Mayhew AJ et al (2019) The prevalence of sarcopenia in community-dwelling older adults, an exploration of differences between studies and within definitions: a systematic review and meta-analyses. Age and Ageing; 48: 1, 48-56.

Mehmet H et al (2020) What is the optimal chair stand test protocol for older adults? A systematic review. Disability and Rehabilitation; 42: 20, 2828-2835.

Mijnarends DM et al (2018) Muscle, health and costs: a glance at their relationship. The Journal of Nutrition, Health and Aging; 22: 7, 766-773.

Mukund K, Subramaniam S (2020) Skeletal muscle: a review of molecular structure and function, in health and disease. Wiley Interdisciplinary Reviews: Systems Biology and Medicine; 12: 1, e1462.

National Institute for Health and Care Excellence (2017) Nutrition Support for Adults: Oral Nutrition Support, Enteral Tube Feeding and Parenteral Nutrition. NICE.

Nazarko L (2022) Healthwise, part 6: improving your healthspan. British Journal of Healthcare Assistants; 16: 5, 228-233.

Office for National Statistics (2022) National population projections: 2020-based interim. ons.gov.uk, 12 January (accessed 6 November 2024).

Patel L (2023) Addressing sarcopenia. bda.uk.com, 14 June (accessed 6 November 2024).

Petermann-Rocha F et al (2021) Global prevalence of sarcopenia and severe sarcopenia: a systematic review and meta-analysis. Journal of Cachexia, Sarcopenia and Muscle; 13: 1, 86-99.

Philpott H et al (2017) Dysphagia: thinking outside the box. World Journal of Gastroenterology; 23: 38, 6942-6951.

Priego T et al (2021) Role of hormones in sarcopenia. Vitamins and Hormones, 115: 535-570.

Ramirez E et al (2022) Comparison between original and reviewed consensus of European Working Group on Sarcopenia in Older People: a probabilistic cross-sectional survey among community-dwelling older people. Gerontology; 68: 8, 869-876.

Roberts HC et al (2019) The challenge of managing undernutrition in older people with frailty. Nutrients; 11: 4, 808.

Roman MA et al (2016) Exercise, ageing and the lung. European Respiratory Journal; 48: 5, 1471-1486.

Rosenberg IH (1997) Sarcopenia: origins and clinical relevance. The Journal of Nutrition; 127: 5 Suppl, 990S-991S.

Shigehara K et al (2022) Relationship between testosterone and sarcopenia in older-adult men: a narrative review. Journal of Clinical Medicine; 11: 20, 6202.

Wan SN et al (2023) Incident sarcopenia in hospitalized older people: a systematic review. PLoS One; 18: 8, e0289379.

Wang J et al (2017) Inflammation and age-associated skeletal muscle deterioration (sarcopaenia). Journal of Orthopaedic Translation; 10: 94-101.

Xu J et al (2021) Sarcopenia is associated with 3-month and 1-year mortality in geriatric rehabilitation inpatients: RESORT. Age and Ageing; 50: 6, 2147-2156.

Yamada Y et al (2017) Developing and validating an age-independent equation using multi-frequency bioelectrical impedance analysis for estimation of appendicular skeletal muscle mass and establishing a cutoff for sarcopenia. International Journal of Environmental Research and Public Health; 14: 7, 809.

Yazar T, Yazar HO (2019) Prevalance of sarcopenia according to decade. Clinical Nutrition ESPEN; 29: 137-141.

Yeung SSY et al (2019) Sarcopenia and its association with falls and fractures in older adults: a systematic review and meta-analysis. Journal of Cachexia, Sarcopenia and Muscle; 10: 3, 485-500.

Yuan S, Larsson SC (2023) Epidemiology of sarcopenia: prevalence, risk factors, and consequences. Metabolism; 144: 155533.

Help Nursing Times improve

Help us better understand how you use our clinical articles, what you think about them and how you would improve them. Please complete our short survey.

Sarcopenia: types, causes, diagnosis and impact (2025)

References

Top Articles
Latest Posts
Recommended Articles
Article information

Author: Allyn Kozey

Last Updated:

Views: 5471

Rating: 4.2 / 5 (43 voted)

Reviews: 90% of readers found this page helpful

Author information

Name: Allyn Kozey

Birthday: 1993-12-21

Address: Suite 454 40343 Larson Union, Port Melia, TX 16164

Phone: +2456904400762

Job: Investor Administrator

Hobby: Sketching, Puzzles, Pet, Mountaineering, Skydiving, Dowsing, Sports

Introduction: My name is Allyn Kozey, I am a outstanding, colorful, adventurous, encouraging, zealous, tender, helpful person who loves writing and wants to share my knowledge and understanding with you.