Table 1.

The evolving concept of cachexia. Listed here are the criteria for the diagnosis of malnutrition, precachexia, and cachexia, including its severity with (from left to right): the corresponding reference, the definition of the cachectic status, and highlights of the main diagnostic criteria used. Cachexia was initially distinguished from anorexia or malnutrition, and, over the years, the progressive nature of muscle wasting (and its relevance to survival) has been highlighted. Ultimately, a staging was proposed for the severity of cachexia depending on the initial status of the patients.

	Source	Definition	Criteria
Cachexia	Evans W. J. et al., 2008	Complex metabolic syndrome associated with underlying illness and characterized by the loss of muscle with or without the loss of fat mass	Weight loss > 5% in the past 12 months and underlying chronic disease; or BMI < 20 and 3 out of the next 5 criteria: Decreased muscle strength (lowest tertile); fatigue; anorexia; low fat-free mass index; abnormal biochemistry: increased inflammatory markers CRP (>5.0 mg/L), IL-6 (>4.0 pg/mL); anemia (<12 g/dL); low serum albumin (<3.2 g/dL)
Chronic disease-related vs. acute disease/injury-related malnutrition	Jensen G. L. et al., 2010	Malnutrition with chronic mild to moderate and severe inflammation, respectively	Weight loss; inflammatory markers
Precachexia	Muscaritoli M. et al., 2010	Early stage of cachexia	Underlying chronic disease; unintentional weight loss ≤ 5% (if any) of usual body weight during the last 6 months; chronic or recurrent systemic inflammatory response; anorexia or anorexia-related symptoms
Cancer precachexia	Fearon K. et al., 2011	Early stage of cancer cachexia	Weight loss < 5%; anorexia and metabolic change
Cancer cachexia	Fearon K. et al., 2011	Multifactorial syndrome characterized by an ongoing loss of skeletal muscle mass (with or without loss of fat mass) that cannot be fully reversed by conventional nutritional support and leads to progressive functional impairment	Weight loss > 5% over the past 6 months (in absence of simple starvation); or: BMI < 20 and degree of weight loss > 2%; or appendicular skeletal muscle index consistent with sarcopenia (males: <7.26 kg/m2; females: <5.45 kg/m2) and any degree of weight loss >2%
Severity of cancer cachexia	Martin L. et al., 2015	Bivariate analysis to estimate the severity of weight loss (WL) as a function of initial BMI: five degrees of severity are associated with differential median survival	Severity from grade 0 (BMI > 25 Kg/m2, WL < 2.5%) to grade 4 (BMI < 20 Kg/m2, WL > 6% or BMI < 22 Kg/m2, WL > 11% or BMI < 28 Kg/m2, WL > 15% etc.)