Janssen et al identified different levels of risk for physical disability in a older adult based on the skeletal muscle mass. The authors are from the University of Kingston (Ontario), University of New Mexico and Tufts University.


Patient selection: >= 60 years


Measurement of skeletal muscle: by bioelectrical impedance, in kilograms (see 02.19.16)


skeletal muscle index = SMI = normalized skeletal muscle mass for height =

= (skeletal muscle mass) / ((height in meters)^2)





low risk

>= 6.76 kg per sq m

>= 10.76 kg per sq m

intermediate risk

5.76 to 6.75 kg per sq m

8.51 to 10.75 kg per sq m

high risk

<= 5.75 kg per sq m

<= 8.5 kg per sq m


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