Editing Cachexia (section)

==Diagnosis==

=== Previous Criteria for Diagnosing Cachexia ===
Doctors used to diagnose cachexia mainly by looking at changes in body weight. A person was considered to have cachexia if they had a low BMI or unwanted weight loss of more than 10%.<ref name="dev-2019" /> However, only using weight is not always a reliable method. Factors like fluid buildup ([[edema]]), tumor size, and obesity can make it difficult to diagnose cachexia.<ref name="dev-2019">{{cite journal | vauthors = Dev R | title = Measuring cachexia-diagnostic criteria | journal = Annals of Palliative Medicine | volume = 8 | issue = 1 | pages = 24–32 | date = January 2019 | pmid = 30525765 | doi = 10.21037/apm.2018.08.07 | doi-access = free }}</ref> These weight-based criteria do not account for muscle loss, which is a key part in cachexia. .<ref name="dev-2019" />

To improve diagnosis of cachexia, experts proposed adding lab tests and symptom evaluations.<ref name="evans-2008" /> With that, a person might have cachexia if they lost  at least 5% of their total body weight in 12 months or had a BMI under less 22&nbsp;kg/m<sup>2</sup> with at least three of the following: weak muscles, fatigue, loss of appetite, low muscle mass, or abnormal labs.<ref name="evans-2008" />

There have also been attempts to define specific types of cachexia, such as cardiac cachexia, which can occur in people with [[congestive heart failure]].<ref name="anker-1999">{{Cite journal |last1=Anker |first1=Stefan D. |last2=Coats |first2=Andrew J.S. |date=1999 |title=Cardiac Cachexia |url=https://linkinghub.elsevier.com/retrieve/pii/S0012369216356586 |journal=Chest |language=en |volume=115 |issue=3 |pages=836–847 |doi=10.1378/chest.115.3.836 |pmid=10084500|url-access=subscription }}</ref> However, there is no widely accepted definition for it.<ref name="anker-1999" />

===Current Criteria for Diagnosing Cachexia ===
Cancer cachexia is now diagnosed based on:

# Unwanted weight loss of more than 5% within 6 months.<ref name="fearon-2011" /><ref name="nishikawa-2021">{{Cite journal |last1=Nishikawa |first1=Hiroki |last2=Goto |first2=Masahiro |last3=Fukunishi |first3=Shinya |last4=Asai |first4=Akira |last5=Nishiguchi |first5=Shuhei |last6=Higuchi |first6=Kazuhide |date=2021-08-06 |title=Cancer Cachexia: Its Mechanism and Clinical Significance |journal=International Journal of Molecular Sciences |language=en |volume=22 |issue=16 |pages=8491 |doi=10.3390/ijms22168491 |doi-access=free |issn=1422-0067 |pmc=8395185 |pmid=34445197}}</ref> 
# For people with a BMI of less than 20&nbsp;kg/m<sup>2</sup>, weight loss of more than 2%.<ref name="fearon-2011" /><ref name="nishikawa-2021" /><ref name="Biswas" /> 
# For people with sarcopenia, weight loss of more than 2%.<ref name="fearon-2011" /><ref name="nishikawa-2021" /><ref name="Biswas" />  
New ways to score and stage cachexia are being explored, particularly in people with advanced cancer.<ref name="nishikawa-2021" />

==== Scoring systems for Cachexia ====
To better understand how bad cachexia is in each person, doctors now use scoring systems like the Cachexia Staging Score and Cachexia Score.<ref name="nishikawa-2021" />

The ''Cachexia Staging Score (CSS)'' looks at weight loss, muscle function, appetite loss, and lab test results to categorize people into four stages: non-cachexia, pre-cachexia, cachexia, and refractory cachexia.<ref name="dev-2019" /> Those in more advanced stages have less muscle mass, more frequent age-related muscle loss, worse symptoms, poorer quality of life, as well as shorter survival periods.<ref name="nishikawa-2021" />

==== Staging ====

* Non-cachexia (0-2 points) - No major weight loss or problems with appetite.<ref name="nishikawa-2021" />
* Pre-cachexia (3-4 points) - Mild weight loss and appetite issues. Early treatment at this stage might slow progression of cachexia.<ref name="nishikawa-2021" />
* Cachexia (5-8 points) - Significant muscle loss that is difficult to reverse and affects daily function.<ref>{{Cite journal |last=Arends |first=J. |last2=Baracos |first2=V. |last3=Bertz |first3=H. |last4=Bozzetti |first4=F. |last5=Calder |first5=P.C. |last6=Deutz |first6=N.E.P. |last7=Erickson |first7=N. |last8=Laviano |first8=A. |last9=Lisanti |first9=M.P. |last10=Lobo |first10=D.N. |last11=McMillan |first11=D.C. |last12=Muscaritoli |first12=M. |last13=Ockenga |first13=J. |last14=Pirlich |first14=M. |last15=Strasser |first15=F. |date=October 2017 |title=ESPEN expert group recommendations for action against cancer-related malnutrition |url=https://linkinghub.elsevier.com/retrieve/pii/S0261561417302285 |journal=Clinical Nutrition |language=en |volume=36 |issue=5 |pages=1187–1196 |doi=10.1016/j.clnu.2017.06.017}}</ref>
* Refractory cachexia (9-12 points) - Severe weight and muscle loss with poor response to treatment and a life expectancy of less than 3 months.<ref name="nishikawa-2021" />

The ''Cachexia SCOre (CASCO)'' is another scoring system that looks at weight loss, inflammation, metabolism, immune function, physical ability, appetite, and quality of life to provide a more detailed assessment.<ref name="dev-2019" />

=== Laboratory Tests for Cachexia ===
Laboratory tests are sometimes used to check for cachexia. Tests that are used include [[albumin]], [[C-reactive protein]], ghrelin, IGF-2, and leptin.<ref name="sadeghi-2018" /> [[Acute phase reactant]]s (IL-6, IL-1b, [[tumor necrosis factor]], IL-8, [[interferon gamma]] and serum cytokines are also studied but are not always reliable for predicting cachexia.<ref name="sadeghi-2018" /><ref name="petruzzelli-2016" /> Laboratory cut-off values are also not the same across different institutions.<ref name="sadeghi-2018" /> There is no single lab test that can confirm cachexia or predict who will develop it.<ref name="peterson-2017" /><ref name="dev-2019" />

=== Imaging ===
One challenge in diagnosing cachexia is measuring muscle loss in an easy and affordable way. Some imaging techniques that can help assess body composition include:

* [[Bioelectrical impedance analysis]] (BIA)
* [[CT scan|Computed tomography]] (CT scans)
* [[Dual-energy X-ray absorptiometry]] (DEXA)
* [[Magnetic resonance imaging]] (MRI)

However, these methods are not widely used because they can be expensive and difficult to access.<ref name="dev-2019" />