Cachexia and Myopathy (LAST COUPLE SLIDES)

Difference between sarcopenia, disuse atrophy, and cachexia

S: loss of lean body mass (muscle+bone) and increased fat mass, associated with aging

DA: loss of muscle and increased fat, associated with decreased PA

C: loss of muscle and loss of fat, associated with chronic disease

Cachexia targets - and increases - - while decreasing - -

• Same proteins for -, only decreased - - for -

Myosin, protein degradation, protein synthesis

• Sarcopenia, protein synthesis for disuse

Cachexia increases - - -, while misuse and sarcopenia decrease - - -

basal energy requirements, basal energy expenditure

How do you treat cachexia (PT)?

• How does this differ from the other two?

Pretty inconclusive

• Sarcopenia: RT, Disuse Atrophy: target specific tissues affected

Myopathy clinical characteristics (4)

Symmetric proximal weakness, low/normal muscle tone, low DTR, normal sensation

Histology differences between myopathy and neuropathy

M: rounded fiber shape and variable fiber size

N: angulated fiber shape and small fiber size

What meds may cause myopathy?

• primarily effect which fiber type, where/laterality (c)

• Lab value (s)

Statins, corticosteroids

• Type 2, proximal symmetric

• Elevated CK

Other causes of myopathy?

Genetic, inflammatory, infectious, metabolic

PAD presents with - and -

neuropathy and myopathy