Patient selection: muscle wasting
Myopenia is muscle loss sufficient to result in impaired functional capacity or to be associated with an increase in morbidity and mortality.
Patients at risk for myopenia:
(1) elderly (age-related sarcopenia)
(2) HIV
(3) COPD
(4) CHF
(5) chronic kidney disease
(6) muscular dystrophy
(7) cancer
(8) critical care
(9) stroke or other neurologic diseases
(10) malnutrition
Criteria for myopenia – one or more of the following:
(1) loss of skeletal muscle mass >= 5% over 6-12 months
(2) less than fifth percentile of skeletal muscle mass for a healthy 30 year old (based on gender)
(3) fat-free mass less than cut-offs considered significant for underlying disease (for COPD < 16 kg per square meter for males and < 15 kg per square meter for females)
Scherbakov et al used the skeletal mass index (SMI) from bioelectric impedance analysis (BIA) with <= 8.5 kg per square meter for males and <= 5.75 kg per square meter for females.
