NUTR 344 Lecture Notes - Lecture 23: Dietitian, Malnutrition, Weight Loss
9 Aug 2019
School
Department
Course
Professor
NUTR 344-L23-Nutritional Assessment and Intervention in
Cancer
Impact of Cancer on Nutritional Status (Graph)
• Presence of tumor
• Host response
• Anti-cancer Tx
Consequences of Compromised status (Graph)
• Intake, Altered Metabolism
o Malnutrition, WL
▪ QoL, response to Tx, Survival
Benefit of assessing nutrition
• Early ID of patients at risk/malnutrition →early
intervention
• Helps design appropriate nutritional support
• Improves patient wellbeing, survival, immune function and morbidity
• Improves eligibility and response to Tx
Nutritional screening vs Assessment
• Screening: process of identifying characteristics known to be associated with nutritional problems
o Purpose is to quickly identify individuals with nutritional risks
o Should be easy to use, cost effective, valid, reliable, sensitive
• Assessment: process of assessment of body compartments and analysis of structure and function of organ
systems and their effects on metabolism
o Most often performed by dietician
o Includes medical and dietary history, physical examination, anthropometric measurements and
analysis of biochemical and functional status. Specific to cancer: review of symptoms.
Nutritional Screening Tools
• NRI: Nutritional Risk Index (Busby) →Albumin % ideal weight
• MUST: Malnutrition Universal Screening Tool
• SNAQ: Short Nutritional Assessment Questionnaire
• NRS: Nutritional Risk Screening-2002
• MNA: Mini-Nutritional Assessment (short and long)
o Both screening and assessment for the elderly
Outline
• Introduction
• Nutritional screening vs. assessment
• Nutritional assessement
o Weight loss
o Muscle mass & strength
o Abnormal biochemical tests
o Subjective assessment
• Nutritional intervention
o Counselling
o Nutritional needs
o Promising therapies
Readings
Nelms—Chapter 23-Nutrition Therapy
(698-708)
WL (Unintentional)
• What is normal vs not normal WL
• Most powerful independent variable tat predicts mortality in CA
• Prime clinical manifestation of cachexia
• Classification of cachexia, based on WL in previous 6 mo
o Moderate >5%
o Severe >10%
o Very severe >15%
• Abnormal WL
o >2% in 1 mt
o >3.5% in 3 mts
o >5% in 6 mts
o >10% in 6-12mts
Loss of muscle mass→assessment tools
• From clinic to research (order→from less precise to more precise)
• Anthropometry: mid-upper arm muscle area
• Creatinine/height index
• 3-methylhistidine excretion
• Bioelectrical impedence (BIA)
• DXA: appendicular muscle mass index
• Imaging techniques: CT scan, MRI
• Densitometry: hydro- or air displacement
• Stable isotope dilution
• Total body potassium counting
MAMA (Mid-upper arm muscle area)
• Calculated from mid-arm circumference and triceps skinfold
• MAMA=(MAC (cm)-piTSK (cm))^2/4pi
o Bone correction=men MAMA-10, women MAMA-6.5
• Low MAMA→<15th percentile for age and sex
Urinary Creatinine and 3-methyl-histidine excretion
• Urinary creatinine=metabolite of creatine phosphate→mainly in skeletal muscle: index of muscle mass
o Creatinine/ht ratio→estimation of the muscle mass
• 3-methylhistidine=released from actin + myosin degradation—estimate of muscle mass degradation
o Marker of myofibrillar protein degradation
o Account for 90% skeletal muscle protein/Also in SM
o 3-MH/creatinine ratio
o total degradation→depend on the amt of muscle in the body
o Not almost measured in clinical labs
• Limitations
o Wide day-to-day variation→need many repeat
o Both techniques require 24hr urine collections and 3 day meat free diet prior
▪ When eating meat→have creatinine and 3-methylhistidine
Bioelectrical impedance
• Estimation of fat-free mass (body fat by difference)
o Based on body water, 2-compartment model
• Foot-to-foot (not recommended) and 4-electrode models:
o Instruments accessible, affordable (<$2000), easy to transport
o Measurement is quick, non-invasive
o Possible to estimate muscle mass
• Limitations:
o Reliable only if hydration status is normal
o Built-in equations are not validated for malnourished or sick persons
o If person got tumor/metastasis→count as lean mass as well—not differentiate from other tissues
Dual energy X-Ray absorptiometry (DXA)
• Imaging technique, based on different tissue density
o Measures bone, soft and fat tissues → total lean body mass and appendicular muscle mass
o Can measure by section
o AMM/height^2 identifies sarcopenia: <7.25 kg/m^2 in men, <5.45 kg/m^2 in women
o Loss of muscle over age→problem when over a certain threshold→defined fairly well
• Limitations:
o Expensive but increasingly accessible in research settings
o Minimal exposure to radiation
o Assumes normal hydration status (less of a problem then BIA)
o Does not account for tumor, metastasis, organ enlargement
Computerized Tomography (CT) scan
• Diagnose and to follow the Tx
• Opportunistic use of oncology
imaging for assessment of tissue
volume
• Track over time
Muscle Strength
• Handgrip strength
o Measured with denamometer
o Cut-offs for low strength
o Men<30kg
o Women<20kg
o Correlates with whole-body muscle strength
• Someone with same muscle mass could have diff strength
• With diet therapy
→
muscle strength could be changed
Functional tests (strength, balance, endurance, etc)
• Gait speed
o Walking speed<0.8m/s in the 4m walking test
o The best predictive marker of morbidity and mortality
• Chair rise
o Time to rise 5 times from a chair without help from the arms
o Test leg strength and power
• 6-min walking test
o Distance walked during 6 minutes
o Endurance test
• Balance test
o Time standing on one foot, or one foot in front of the other
• Chair rise and walking test→discriminate for less functionality
• Gait speed→when the person is actually affected
Document Summary
Outline: nutritional screening vs. assessment, nutritional assessement, weight loss, muscle mass & strength, abnormal biochemical tests, subjective assessment, nutritional intervention, counselling, nutritional needs, promising therapies. Impact of cancer on nutritional status (graph: presence of tumor, host response, anti-cancer tx. Consequences of compromised status (graph: intake, altered metabolism, malnutrition, wl, qol, response to tx, survival. Benefit of assessing nutrition: early id of patients at risk/malnutrition early intervention, helps design appropriate nutritional support, improves patient wellbeing, survival, immune function and morbidity, improves eligibility and response to tx. Nutritional screening vs assessment: screening: process of identifying characteristics known to be associated with nutritional problems. Mama (mid-upper arm muscle area: calculated from mid-arm circumference and triceps skinfold, mama=(mac (cm)-pitsk (cm))^2/4pi, bone correction=men mama-10, women mama-6. 5, low mama <15th percentile for age and sex. Computerized tomography (ct) scan: diagnose and to follow the tx, opportunistic use of oncology imaging for assessment of tissue volume, track over time.
