Lecture 9 Flashcards Preview

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Flashcards in Lecture 9 Deck (31):
1

Nutritional Status

balance between nutrient intake and expenditure (health condition)
Measures of nutritional status reflect intake, absorption, metabolism, storage and excretion

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Assessments of Nutritional Status

1. Individual level: diagnosis, screening, intervention and monitoring
2. Population level: policy setting, programme evaluation, nutritional surveillance

3

Integration of Nutrition into routine clinical case

-consultation or assesment has limited time- gp or hospital
1. Past medical history/Family history (ask about related nutritional issues)
2. Medications, OTC/supplements/herbs (70% takes OTC/non-pharmacteuical supplement, some do interact with drugs. therefore if prescribe medication need to know it wont interact)
3. Diet/social/Lifestyle history (family support, have children)
4. Review of systems
5. Physical examination
6. Laboratory evaluation (blood tests etc)
Final Result: 7. Assessment and plan

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ABCD(E) of nutrition assessment

Anthropometric (physical examination)
Biochemical (blood tests)
Clinical (general)
Dietary (diet)
Economical/Social

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Anthropometric

Changes in physical dimensions (weight) and body composition – including rate of change
-very useful in clinical practice as can tell alot about condition (e.g. chronic phase related to chronic clinical condition (unintentional weight loss over long period. e.g. unknown bowel cancer for few years.) vs acute phase related to acute clinical condition (unintentional weight loss over short period/quickly. e.g. could be caused by diarrhea and vomiting. Usually regained in a short period of time))
1. Weight
2. Height (standing up. children under 2 lying down. but some may not people able to be measured e.g. bed bound or wheelchair: use other length measurements which can be put into charts to indicate height) /Stature/knee height/total arm length/arm span (esp. important in paedeatrics. )
3. Circumferences (wasit circumference good indicator for central adiposity)
More invasive rarely used in clinical practise
4. Skinfolds
5. Bioelectrical impedance
6. Body density: under water weighing, BodPod
7. Isotope dilution (total body water)
8. DEXA
9. Total body electrical conductivity
10. Magnetic resonance imaging

6

BMI

Body Mass Index (BMI)-weight for height in a suggested range
BMI= weight (kg) / Height (m2)
-used alot clinically
World Health Organization 2000 (uses only one cut off). * Only health conditions associated with increasing BMI.
-still a blunt measurement/instrument
-larger lean body mass:fat. therefore actually low risk of disease (Joan Olaumu).-athletes who need to be muscular for their sport
-used to have different cut offs for different ethnic groups, as assumed:
-Pacific Island+ Maori always had higher fat mass:leanbody mass, therefore their cut offs for disease were different(higher). Asian and Indian lower cut offs

7

Principal BMI cut-off points for adults aged 18 years and over

Underweight = high risk of undernutrition

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Percentage Age weight Loss

Change in Body Weight – very useful
1. Unintentional
2. Relate to time
% Weight loss = Usual weight - current weight (kg) x 100 Usual weight
3. Recalled “well” weight often more reliable than standard tables for estimating weight loss

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Evaluation of Weight Changes

Time -Significant Weight Loss - Severe Weight Loss
1 week - 1-2% - >2%
1 month - 5% - >5%
3 months - 7.5% - >7.5%
6 months - 10% - >10%

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Body composition

Body weight= fat + lean tissue (including water)
a) Ideal Body Fat:
-Men 12-20% body fat
-Women 20-30% body fat
b) Increased Health Risks
– >22% fat in young men & >25% in men over 40
– >32% in young women & >35% in women over 40

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Distribution of Body fat

-not only higher BMI but wlaso where fat is increases risk of CDV, Liver diseases and some cancer
May relate to disease independently of obesity (e.g. abdominal fat and type 2 diabetes)
1. Waist:Hip ratio:
– correlates with body fat – increased mortality risk > 0.8 women, >1.0 men
2. Waist circumference:
increased mortality risk > 88 cm women, > 102 cm men
-can be difficult and sensitive to do
-ideally want to do on direct skin, but often done ontop of thin shirt

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Waist circumference cut-off points for adults aged 18 years and over

Risk of metabolic complications - Men - Women
Average risk -

13

Biochemical Assessment

1. To detect subclinical or marginal deficiencies (could just look-see malnourished)
2. To enhance or support other nutritional data
3. Nutrients in blood or urine, biopsy (not many tests are that sensitive to being able to truely evaluate nutritional status, few biochemical biomarkers of nutrients that are reliable)
4. In vivo response to nutrient supplementation e.g Hb and iron (response to supplementation or intervention. Want to ensure biochemisty has worked therefore do blood tests eg)

14

Biochemical Tests examples

1. Serum albumin level :Measures main protein in blood ;Determines protein status
2. Serum transferrin level - Indicates iron-carrying protein in blood

15

Clinical and Physical subjective evaluations

Subjective evaluation of overt signs/symptoms-includes medical history
1. Signs & symptoms of deficiency/toxicity whether likely to be reversible)
2. Measurements of physiologic performance and activities -functional status –Oral
and dental health
3. Cognitive status
4. Use of drugs – drug-nutrient interactions etc

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Clinical Assessment

1. Detect signs and symptoms of malnutrition (/deficiency/toxicity) -whether likely to be reversible (difficult to physically evaluate nutritional status unless an extremity (anorexia or obese). Goiter is obvious- iodene deficiency. Need to evaluate more effectively)
2. Medical history
3. Physical assessment: hair, skin, eyes, mouth, bones (grip strength good indicator for elderly lean body weight, often lost with age)
4. Physiological Tests e.g. Immune competence, taste ,acuity, night blindness, muscle function, cognitive function
-Measurements of physiological performance, functional status - Oral and dental health(enought teeth to chew meat/fibre).
-Cognitive status (good indicator)
5. Deficiency usually severe before clinically evident
6. Symptoms may be caused by non-nutritional factors – secondary deficiency
7. Symptoms may relate to several nutrients
-Use of drugs - drug-nutrient interactions

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Dietary Evaluation Measurements

Important but difficult to do throughly due to limited time
Measurements of food consumption observed/reported:
1. Food and beverage intake – quality of diet (ask about apetite) - dont always need to do for long and simple probelm
2. Food consumption patterns (changes and trends) and preferences 3. 24 Hour Recall
3. Usage of supplements (and effect on nutrient 4. Food Records (diaries) intake)
4. Feeding practices e.g. institutions
5. Food security/insecurity (alot of young and old are food insecure, not enough money to bind enough food for adequate nutritional intake. -limited access or simply not enough money)
-Frank's wife died, now frank alone - could also have limited abilites re preparation of food (often seen in traditional elderly couples)
-estimation of dietary requirements - realistically hard to do with time pressure
- some use apps for patients to pre-input daily intake before appointment - see energy consumption. - difficult to do in acute care

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Main types of approach for Dietary Evaluation

1. Diet (food) History
2. Food Frequency Questionnaire 3. 24 hour recall
4. Food records

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Assessments of Dietary intake

Compare intake to:
1. Recommended Dietary Intakes for age and gender
2. Food and Nutrition Guidelines- recommended servings of food groups
3. Healthy Eating plate models and Dietary Pyramids
-pros and cons and which more clinical suitable

20

Measurement of Body composition

Body Weight - usual scales
Fat Free Mass + Fat -special scales. only good if used on same person sequentionally to see one individuals fluctuation, but not that accurate (avoid use)
Cell Mass + Extracell. Mass + Fat
Bone + Protein + Water + Fat
-use research equipment

21

Fat Fold Measurements

Esimate body fat by using a calper to gauge the thickness of a fold of skin on:
1. the back of the arm (over the triceps)
2. Below the shoulder blade (subscapular)
3. and in other places (including lower body sites)
and then comparing these measurements with standards
-measure subcutaneous
-need to be skilled to use effectively
-equations have to be carefully used according to where the site of the fat fold is measured
-often incorrectly

22

Hydrodensitometry

Measures body density by weighing the person first on land and then again when submerged in water
The difference between the person's actual weight and underwater weight provides a measure of the body's volume.
A mathematical equation using the two measurements (volume and actual weight) determines body density, from which the percentage of body fat can be estimated

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Air Displacement Piesthysmography

Estimates body composition by having a person sit inside a chamber while computerised sensors determine the amount of air displaced by the person's body

24

Dual energy X-ray Absorptiometry (DEXA)

uses two low dose X-rays that differentiate among the fat-free soft tissue (lean body mass), Fat tissue and bone tissue.
Provides a precise measurement of total fat and its distribution in all but extremely obese subjects
-clinically used for bone mass often

25

Bioelectrical Impedance

measures body fat by using a low-intensity electrical current.
Because electrolyte containing fluids, which readily conduct an electrical current, are found primarily in lean body tissues.
The leaner the person, the less resistance to the current.
The measurement of electrical resistance is then used in a mathematical equation to estimate the percentage of body fat
-principle same as of normal weight scales

26

Changes in body weight equation

% Weight loss = (Usual weight -current weight (kg) x100) / usual weight
unintentional gain or loss indicate health status
-he was within a normal health range (not obese) therefore losing this much weight without pathology isnt healthy (made him go in underweight group)

27

Low Hb levels

Hb in RBC
low HB indicates Anaemia, major cause of dietary iron deficiency
(iron deficiency anaemia)
-could be due to bleeding ulcer, cancer in large bowel
inadequatey dietary intake of iron

28

What are the biomarkers for iron

good biomarkers
B12 and Folate
useful to evaluate iron status and can easily supplement him

29

Review of Systems

General: appetite changes, weight loss/gain, clothes tighter/loser (often people dont own scales)
-general is good way to start conversation. can also be a good indicator
Skin: appearance (pinch test. doesnt bounce back , not elastic, good indicator of dehydration)
(beta-caratonemia - eat alot of carrots, yellow palms of skin. yellow- could also be jaundice-liver infection/problem)
GI symptoms/alimentary: abdominal pain (e.g. when eating), nausea, vomiting (good indicator of not so much primary deficiency, but of a disease that might be effecting the dietary intake. e.g. stomach cancer/oesophageal stcture- feel sick and difficulting swallowing)
-bowel changes (enough dietary fibre consumed)
-difficulty/pain swallowing, early satiety, indigestion, heart burn
-mouth lesions-ulcers, tooth decay, sore gums, teeth (oral health, typically older people, not enough teeth, poorly fitted dentures, sore mouths generally- enough VitC and zinc)
-extreme Vit C = cause scruvy. recurrent ulcers and sore mouths
-sore gums and tongue can also be caused by adverse effects to some treatments or medications (all influence peoples ability to eat)

30

Subjective Global Assessment

Used as hospital screening tool
-score indicates whether need intervention or need dietitian
-in H care and other wards (not whole but should be)
SGA most popular
A: History
1. Weight changes (scored re past 6m or 2w)
2. Food intake (scored re overall has increased or decreased + type of change (liquid, solid, unable to eat, calorie)
3. GI symptoms- as would be major symptoms which would impair someone's dietary intake
B: Physical Examination (general overall)
1. Loss of Subcutaneous Fat
2. Muscle Waisting

Overall SGA classification:
Normal or well-nourished 6-7 (no intervention or referral)
Mild to moderately malnourished 3-5 in most categories (no referral but doctor/nurse need to know and some intervention at ward level)
Severely malnourished 1-2 (intervention and referral - e.g. nasogastric feeding into stomach, or intravenous feeding into vein)
Scoring systems/screening Really useful for triaging patients towards appropriate nutritional care and easy to use

31

What is information from nutrition assessments used to do?

1. Diagnose nutritional problems
2. Plan nutrition care
3. Evaluate nutrition intervention
4. Complete assessment includes ABCDE - easy for clinical easy consultation
5. Should be part of standard care -increased awareness to be part of routine assesment