The Cachexia Index (CXI) is a measure of cachexia in a patient, most often used in oncology.
Parameters:
(1) skeletal muscle index
(2) serum albumin in g/dL
(3) neutrophil to lymphocyte ratio (NLR)
skeletal muscle index =
= (measure of skeletal muscle) / ((height in meters) ^2)
The measure of skeletal muscle may vary depending on the study:
(1) skeletal muscle mass by bioelectric impedance analysis
(2) skeletal muscle area of the iliopsoas muscle at L3 in imaging studies
(3) skeletal muscle area of paraspinal and abdominal muscles at L3 in imaging studies
The choice of the skeletal muscle measure would affect the final CXI value.
neutrophil to lymphocyte ratio =
= (percent neutrophils in the differential count) / (percent lymphocytes in differential count)
cachexia index =
= (skeletal muscle index) * (albumin) / (NLR)
Interpretation:
• The CXI is impacted by the sex of the patient.
• The prognosis is worse for patients with a low CXI.
• For evaluation it is important to standardize the skeletal muscle measure being used.
For Yan et al (using option 3 above) a low CXI for a male was < 483,25 for males and < 372.96 for females.
For Shimgaki et al (using option 2 above) a low CXI for a male was < 22.90 for a male and < 16.58 for a woman)
