Nutritional assessment and approach in cancer Flashcards
How does cancer impact nutritional status
Cancer impacts nutritional status via:
1) Presence of tumor
2) Host response to tumour
3) Anti-cancer treatment
Consequences of compromised status
reduced intake + altered metabolism lead to -> Malnutrition + Weight loss
All this leads to:
1) Decreased Quality of life
2) ↓ Response to treatment (may have to stop/delay treatment)
3) ↓ Survival
Benefits of assessing nutrition
• Early identification of patients at risk, or experiencing malnutrition allows for early intervention
• Helps design appropriate nutritional support
• Improves patient wellbeing, survival, immune function and
reduced morbidity
• Improves eligibility and response to treatment
Define screening
Define assessment
Screening: process of identifying characteristics known to be associated with nutritional problems
Assessment: process of assessment of body compartments and analysis of structure and function of organ systems and their effects on metabolism
Goals and process of screening vs goal and process of assessment
Screening:
• To detect nutritional disturbances at an early stage,
• Should be !!repeated!! as clinical condition changes
• Tool should be easy to use, cost effective, valid, reliable, sensitive
Assessment
• Most often performed by dietitian
• Includes medical and dietary history, physical examination, anthropometric measurements and analysis of biochemical and functional status. Specific to cancer: !!! review of symptoms with nutrition impact!!!
Name nutritional screening tools
- NRS: Nutritional Risk Screening-
- MUST: Malnutrition Universal Screening Tool
- MNA: Mini-Nutritional Assessment
* Both screening (short form) and assessment (long form) for the elderly
how to calculate % weight loss
% weight loss = (Initial weight – current weight)/Initial weight X 100
What is the most powerful independent variable that predicts mortality in cancer?
unintentional weight loss measure
What is the prime clinical manifestation of cachexia
unintentional weight loss
unintentional weight loss cut-offs for classification of cachexia, based on weight loss in previous 6 months
- Moderate > 5%
- Severe > 10%
- Very severe > 15%
What is the correction that should be made when measuring weight loss
Weight should be corrected for excessive fluid loads (pleural effusion, ascites, edema)
% weight loss that is determined as Significant loss or Severe loss in 1 week 1 month 3 months 6 months Unlimited
1 week: Significant loss: 1-2%; Severe loss: >2%
1 month: Significant loss: 5%; Severe loss: >5%
3 months: Significant loss: 7.5%; Severe loss: >7.5%
6 months: Significant loss: 10%; Severe loss: >10%
Unlimited: Significant loss: 10-20%; Severe loss: >20%
What are the components of dietary assessment in cancer patients?
- Energy and protein intake: 24h recall or rapid estimation
- Changes in food and fluid intake
- Adequacy of nutrient intake
- Changes in type, texture or temperature of foods or liquids: aversion to food groups? e.g. meat as it often tastes metallic
- Use of medical food supplements
- Changes in meal or snack patterns
- Intake from enteral or parenteral nutrition
- Natural health products, alternative medicine products, medications; natural health products may have interactions and impact on weight
- Factors affecting access to food: e.g. doing groceries, ability to cook
Loss of muscle mass: assessment tools
arranged in the order from those used in clinic conditions to research conditions
Clinic-> research
• Anthropometry: mid-upper arm muscle area: not sensitive; <15% is cut- off for low measure
• Creatinine/height index
• 3-methylhistidine excretion: has been shown to be a reliable index of muscle protein breakdown
• 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
How is MAMA calculated? What is the cut-off value?
Mid-upper arm muscle area (MAMA)
• Calculated from mid-arm circumference and triceps skinfold
• Bone correction has to be included
• Low MAMA : < 15th percentile for age and sex
What is Urinary creatinine and how is it used as an indicator of muscle mass?
Urinary creatinine is a metabolite of creatine phosphate, mainly found in skeletal muscle: index of muscle mass
• Creatinine / height ratio
What is 3-methylhistidine and how is it used as an indicator of muscle mass?
3-methylhistidine is released from actin and myosin degradation → marker of myofibrillar protein degradation (account for ~ 90% skeletal muscle protein)
• 3-MH/creatinine ratio
What are the limitations of Urinary creatinine and
3-methyl-histidine as assessment tools?
• Wide day-to-day variation
• Both techniques require 24 h-urine collections and 3 day-meat free diet prior
thus, these are not used often
WHat is Bioelectrical impedance?
- Estimation of fat-free mass (body fat by difference)
* based on body water, 2-compartment model
What are the models of Bioelectrical impedance measures? Are they good or bad?
Foot-to-foot (not recommended) and 4-electrode models:
• Instruments accessible, affordable (
Limitations of Bioelectrical impedance measures
- Reliable only if hydration status is normal
* Built-in equations are not validated for malnourished or sick persons
What is DXA?
METHOD OF CHOICE TO MEASURE MUSCLE MASS
Dual energy X-ray absorptiometry (DXA)
• Imaging technique, based on different tissue density
• Measures bone, lean soft and fat tissues → total lean body mass and
appendicular muscle mass
What are the diagnostic cut-offs for dexa?
AMM/height2 identifies sarcopenia: <7.25 kg/m2 in men, <5.45 kg/m2 in women
DEXA limitations and advantages
• Expensive but increasingly accessible in research settings
• Minimal exposure to radiation
• Assumes normal hydration status
• Does not account for tumour, metastasis, organ enlargement
- cannot detect enlarged organs-> increased lean mass results