Sarcopenia and Kidney disease Flashcards
How has the definition of Sarcopenia developed over the years?
- 2010 - age related disease of skeletal muscle function
- 2016 - international classification of diseases-10 code
- 2019 - change to muscle function as key criteria in defining probable sarcopenia
- 2024 - revert back to sarcopenia being about mass and function
What factors can accelerate sarcopenia?
Sarcopenia is intrinsic to the ageing process but can be accelerated by various factors, including
- increased inflammation
- increased ammonia levels
- decreased testosterone
- increased myostatin levels
- decreased IGF-1
What is the most widely used criteria for defining sarcopenia?
Explain the process of diagnosis?
European Working Group on Sarcopenia in Older People
F- find people with sarcopenia - clinical susption of sacropenia of SarcF form
A - assess its presence - grip strength
C - confirm its presence - echo testing
S - severity of the case - gait speed, or up & go test
What are the primary and secondary causes of sarcopenia?
primary - age-related - when no other specific cause is evident
secondary - when casual factors other than (or in addition to) aging are evident
What are the 2 biggest risk factors for sarcopenia?
- 2 biggest risk factors are physical inactivity(can be changed with specialist help) and multimorbidity
Describe chronic kidney disease:
What is it characterised by?
- CKD is the progressive loss of kidney function over time affecting ~1 in 10 people
- Kidney disease can be divided into three approximate cohorts: non-dialysis, dialysis, and transplant (RRT)
- Patients characterised by increased CVD, muscle wasting, poor physical and exercise capacity
What are the stages of CKD?
- Stage 1: kidney damage but normal function 90-100%
most people display this as they age - Stage 2: damage & mild loss of function 89-60%
- Stage 3a: mild-moderate loss of function 59-45%
- Stage 3b: moderate-severe loss of function 44-30%
- Stage 4: severe loss of function 29-15%
- Stage 5: kidney failure <15%, need for transplant otherwise will die in 6 months
What happens to the recognition of sarcopenia in CKD patients?
- CKD prevalence almost doubles in dialysis patients
- CKD is described as a model of ‘accelerated aging’
- sarcopenia is underrecognised in those with CKD
- discrepancies in definitions/criteria used
- no formal assessment
- confused with malnutrition and protein-energy wasting
- Depending on the definition used, can change the prevalence of sarcopenia, aswell as types of participants used
what are the 3 statuses in defining sarcopenia?
- probable sarcopenia: low hand grip strength
- confirmed sarcopenia: plus low muscle mass from BIA
- severe sarcopenia: plus poor walking speed
How can the prevalence of sarcopenia vary in studies?
Low prevalence of sarcopenia could be due to the way biobank advertised the study
- Generally the healthier population were interested in taking part
How does physical inactivity and multi morbidity affect sarcopenia prevalence?
physical inactivity - participants in highest quartile of METs per week were 43% less likely to have sarcopenia
mulitmorbidity - participants with 3 or more comorbidities were 2.3 times more likely to be sarcopenic.
How did the prevalence of CKD effect sarcopenia?
- those without CKD and probable sarcopenia had a much better survival that those with CKD and without sarcopenia.
- if you have CKD = increased death risk
- In participants with CKD, probable sarcopenia was associated with an increased risk of developing end-stage renal disease (ESRD). Adjustment for age, comorbidities, inflammation
- People with CKD are at higher risk of developing sarcopenia
What is low grip strength associated with in CKD patients?
Low grip strength is correlated with clinical outcomes such as increased functional limitations, longer hospital stays, poor health-related quality of life and mortality. This is easily measured and doesn’t need a specialist
How do sarcopenia and CKD affect mortality?
- 10 yr survival in sarcopenia and CKD patients is 4% lower compared to non-sarcopenic CKD patients
- Having CKD has a far greater impact on survival than sarcopenia i.e. those without CKD and probable sarcopenia had a much better survival than those with CKD and without sarcopenia
- Overall CKD and sarcopenia = death
How did sarcopenia affect the prevalence of Covid-19?
Impacted on risk of severe Covid-19
- Effect on immune function
- Individuals with probable sarcopenia were 64% more likely to have severe Covid infections.
- Those with sarcopenic obesity were 2.6 times more likely to have severe covid.
What happens following a kidney transplant?
- muscle mass decreases (sarcopenia)
- fat mass increases (obesity)
- BMI increases (sarcopenic obesity)
Peoples muscle mass reduces after surgery transplant
But body weight remains the same
This is why BMI is important as it masks this transition
Describe muscle quality post-transplant:
- increased muscle size = increased physical performance and strength
- lack of evidence showing this in CKD patients
- however, loss in function is observed independently of muscle mass in HD patients and older adults
What factors influence muscle quality?
- composition
- metabolism
- fibrosis
- neuro-muscular activation
influence muscle quality
Define Myosteatosis:
- Myosteatosis, the intramuscular infiltration of fat, has emerged as an important factor underpinning muscle quality. Fat infiltration into the muscle, can reduce quality of the muscle
How can muscle quality be determined?
- MRI can give a clear indication of muscle quality including infiltration of fat and fibrosis
- costly and requires expertise and resources
- also evaluated by non-invasive, low cost ultrasounds
- echo testing can represent increased intramuscular adipose tissue and intramuscular fibrosis (white is fat, darkness is muscle)
What is more important? quality or quantity?
linear relationship between RF-CSA(mass) & echo intensity(quality), both important
- but increased size of muscle can override quality of muscle & increase performance
How is higher echo intensity(lower muscle quality) negatively correlated with physical performance?
- fat infiltration alter fibre orientation and decrease elasticity & impairs mitochondrial metabolism(decreasing oxidative capacity)
- non-contractile fibrotic tissue = decrease fibre direction (type II) = increased stiffness and decreased contractile ability
- Reduces generation of ATP when fat gets into muscle can change the structure of the muscle
Why CKD?
- Myosteatosis has been associated with overall body fat and obesity (and diabetes) and physical inactivity and inflammation
- Skeletal muscle fibrosis common in CKD1
- Increase myostatin = increase fibro/adopogenic progenitor cells
- Metabolic abnormalities from CKD uremic milieu
How can patients overcome sarcopenia?
- The first treatment for sarcopenia is PA
- 150 min per week of moderate to vigorous aerobic physical activity, muscle-strengthening activities at least twice a week, and activities that challenge balance, in addition to several hours of light physical activity (i.e., standing)
- However, resistance training is recommended as the primary mode of treatment for age-related muscle-wasting diseases as it can improve muscle mass and function in the elderly
- Protein intervention to help sarcopenia: older adults should consume high-quality animal-derived protein sources, such as dairy, eggs, and meat, as it results in greater muscle hypertrophy when combined with resistance training
What is the overall consensus for overcoming sarcopenia in older adults?
Overall: Encouraging older adults to participate in resistance training at least twice a week and consume ~1.6 g/kg/day of high-quality protein will reduce risks for many of the negative consequences of sarcopenia
