Seminar about goals and different methods to assess nutritional status

1. Nutritional Assessment
By
Ahmed Abudeif Abdelaal
Assistant Lecturer of Tropical Medicine & Gastroenterology
Sohag Faculty of Medicine
January, 2017

2. Goals of nutritional assessment
1) To identify the presence and type of malnutrition.
2) To define health-threatening obesity.
3) To devise suitable diets as prophylaxis against disease later
in life.

3. Nutritional assessment includes the following:
- Clinical history.
- Physical examination.
- Composite screening tools.
- Anthropometric measures.
- Laboratory assessment.
- Measuring body composition.
- Miscellaneous tests.

4. Clinical history
1) The timing and amount of weight loss:
- A recent unintended weight loss of > 5% of usual weight
should prompt efforts to diagnose the underlying disorder or
social circumstance.
2) Medical illnesses, e.g. DM, liver cirrhosis.
3) Medications.
4) Gastrointestinal symptoms: anorexia, nausea, vomiting,
dysphagia, abdominal pain, diarrhoea.

5. Clinical history
5) Diet habits:
a) Eating fewer than two meals per day.
b) Following a prescribed diet.
c) Food allergy or intolerance.
d) Alcohol consumption.
e) Dietary supplement intake including vitamins, minerals and herbs.
f) Dental status.

6. Clinical history
6) Social habits: eating alone, needing assistance in self-care.
7) Economic status: having enough money for food.
8) Mental status: especially the presence of depressive
symptoms.

7. Physical examination
- The physical findings of deficiency syndromes of vitamins,
essential fatty acids, and trace metals are relatively insensitive
and nonspecific.
- Only marasmus and cachexia syndromes are evident at
examination.
- Loss of subcutaneous fat and skeletal muscle is manifested
by sunken temples, thin extremities, wasting of the muscles of
the hand, and, rarely, edema.

8. Physical examination
- Kwashiorkor in children is characterized by severe edema
and a potbelly appearance from hepatomegaly and ascites.
However, these clinical signs can rarely present in cases of
hypoalbuminemic malnutrition that develops in the setting of
systemic inflammation resulting from disease in industrialized
societies.

9. Clinical signs and symptoms of nutritional
inadequacy in adult patients

10. Composite screening tools
- Investigators have made numerous attempts to combine the
various components of nutritional assessment, including clinical
history, physical examination, anthropometry, and serum
proteins, into a single score.
- Some of the more widely used tools include the following:
1) Subjective global assessment.
2) Nutritional risk index.
3) Mini-nutritional assessment.
4) Malnutrition universal screening tool.

11. Composite screening tools
Subjective global assessment
(SGA)
- Simple clinical bedside tool which
assess nutritional status based on
features of the history and physical
examination.
- SGA is highly predictive of
nutrition associated complications.

12. Composite screening tools
Subjective global assessment (SGA)
- Value of SGA:
1) Identifying malnutrition.
2) Distinguishing malnutrition from a disease state.
3) Predicting outcome.
4) Identifying patients in whom nutritional therapy can alter
outcome.

13. Composite screening tools
Subjective global assessment (SGA)
- Components of SGA:
 From history:
1) Weight loss.
2) Dietary intake.
3) Presence of gastrointestinal symptoms.
4) Functional capacity.

14. Composite screening tools
Subjective global assessment (SGA)
- Components of SGA:
 From physical examination:
1) Subcutaneous fat.
2) Muscle wasting.
3) Oedema.
4) Ascites.

15. Composite screening tools
Subjective global assessment (SGA)
- The findings of the history and physical examination are used
to categorize patients as being:
- Well nourished (category A).
- Having moderate or suspected malnutrition (category B). or
- Having severe malnutrition (category C).

17. Anthropometric measures
1) Body weight
- Is a useful element in the physical examination, it is
expressed as a relative value to evaluate the patient in relation
to the healthy population.
- Weight and height are easily obtained, and standards for
comparison have been established.

18. Desirable weight in pounds in
relation to height for men and
women 25 years or older

19. Anthropometric measures
1) Body weight
- The major confounding factor that limits the value of weight as
an index of PEM is the tendency for water retention with
disease, and thus weight gain may not reflect an increase in
lean body mass or protein content.
- Fluid retention confound weight assessment in patients with
heart failure, end-stage liver disease and severe renal disease.

20. Anthropometric measures
2) Body mass index (BMI)
- BMI has gained favor as a nutritional measure because of two
valuable attributes:
1) It is relatively independent of height.
2) the same standards apply to male and female patients.
- BMI is better correlated with outcome than are weight and
height.

21. Anthropometric measures
2) Body mass index (BMI)
Category
BMI (kg/m2)
From To
Very severely underweight 15
Severely underweight 15 15.9
Underweight 16 18.4
Normal (healthy weight) 18.5 24.9
Overweight 25 29.9
Obese Class I (Moderately obese) 30 34.9
Obese Class II (Severely obese) 35 39.9
Obese Class III (Very severely obese) 40

23. Anthropometric measures
3) Upper arm anthropometry
- Triceps skinfold thickness (TSF) is the most practical
technique to estimate body fat.
- Generally, a value lower than the 5th percentile is used to
define abnormality.
- The principal value of the TSF measurement is to determine
the arm muscle circumference (AMC) or arm muscle area.

24. Anthropometric measures
3) Upper arm anthropometry
- The AMC is a specific measure of protein-energy malnutrition
if the 5th or 10th percentile is chosen as the cutoff point, and it is
particularly valuable in patients in edematous states and in
amputees, in whom weights are inaccurate or insensitive.

25. Fifth, tenth, and
fiftieth percentiles for
triceps skinfold and
mid-upper arm muscle
circumference of US
men and women

26. Anthropometric measures
4) Waist and hip circumference
a) Waist circumference
- It is measured at the level of the umbilicus.
- It gives and indication of the degree of abdominal obesity.
b) Hip circumference
- It is measured at the level of the greater trochanter.

27. Anthropometric measures
c) Waist : hip ratio
- To assess body fat distribution whether android (apple
shaped, central, visceral, abdominal) obesity or gynoid (pear
shaped) obesity.

28. Apple shape Pear shape
Excess fat on the abdomen (more
visceral fat)
Excess fat on the thighs and
buttocks (less visceral fat)
Common in men Common in women
Significant correlation with metabolic
syndrome, DM, cardiovascular risk
Non significant correlation

29. Laboratory assessment
A) Serum proteins
1) Albumin
- Normal value (3.5 – 5.5 g/dl).
- Half life is 18 – 20 days.
- It is the traditional standard for nutritional assessment.
- It is used to separate the two principal forms of PEM.

30. Laboratory assessment
A) Serum proteins
1) Albumin
- Hypoalbuminemia is a strong predictor of risk for morbidity
and mortality.
- In almost all cases, except for hereditary analbuminemia,
excessive loss secondary to nephrotic syndrome and protein-
losing enteropathy, hypoalbuminemia identifies the recent or
ongoing presence of a systemic inflammatory response.

31. Laboratory assessment
A) Serum proteins
1) Albumin
- A value for serum albumin of less than 3.5 g/dl is considered
to indicate a mild systemic inflammatory response, whereas a
value of less than 2.4 g/dl represents a severe systemic
inflammatory response.
- Factors affecting serum albumin levels:

32. Increased in Decreased in
Dehydration Overhydration/ascites/eclampsia
Marasmus Hepatic failure
Blood transfusions Inflammation/infection/metabolic stress
Exogenous albumin Nephrotic syndrome
Protein losing enteropathy
Burns
Trauma/post-operative states
Kwashiorkor
Collagen diseases
Cancer
Corticosteroid therapy
Bed rest
Zinc deficiency
Pregnancy

33. Laboratory assessment
A) Serum proteins
2) Other proteins (prealbumin, transferrin, retinol binding
protein)
- These proteins do not reliably identify the presence and
severity of the systemic inflammatory response any better than
does albumin, but they reflect the nutritional response more
quickly when inflammation lessens.

34. Laboratory assessment
A) Serum proteins
2) Other proteins
a) Prealbumin (transport protein for thyroxine):
- Normal value (20 – 40 mg/dl).
- Half life is 2 days.
- Factors affecting serum prealbumin levels:

35. Increased in Decreased in
Severe renal failure Post-surgery
Corticosteroid therapy Liver disease/hepatitis
Oral contraceptives Inflammation/infection/stress
Dialysis
Hyperthyroidism
Sudden demand for protein synthesis
Pregnancy
Significant hyperglycaemia

36. Laboratory assessment
A) Serum proteins
2) Other proteins
b) Transferrin:
- Normal value (204 – 360 mg/dl).
- Half life is 7 days.
- Factors affecting serum transferrin levels:

37. Increased in Decreased in
Iron deficiency Pernicious anaemia/folate deficiency anaemia
Dehydration Anaemia of chronic disease
Pregnancy (3rd trimester) Overhydration
Oral contraception/estrogens Chronic infection
Chronic blood loss Iron overload/iron Dextran therapy
Hepatitis Acute catabolic states
Hypoxia Uraemia
Chronic renal failure Nephrotic syndrome
Severe liver disease/hepatic congestion
Kwashiorkor
Age
Cancer
Corticosteroid therapy
Zinc deficiency

38. Laboratory assessment
A) Serum proteins
2) Other proteins
c) Retinol binding protein:
- Half life is 12 hours.

39. Laboratory assessment
B) 24 hour urinary creatinine
- Normally 500 – 1200 mg/day.
- Low value indicates muscle wasting.

40. Laboratory assessment
C) Creatinine – height index (CHI)
- It is determined by measuring 24 hour urinary creatinine
excretion in relation to the patients height while the patient is
consuming a creatine and creatinine free diet.
- It indicates protein depletion.
- CHI = (24 hour urine creatinine × 100) / (expected 24 hour
urine creatinine for height).

41. Laboratory assessment
C) Creatinine – height index (CHI)
Category CHI
Normal > 80%
Mild protein depletion 60 – 80%
Moderate protein depletion 40 – 60%
Severe protein depletion < 40%

42. Laboratory assessment
D) Quantitative fecal fat measurement
- Is helpful to identify those patients with steatorrhoea, and the
loss of fat calories that result.
- Normally it is less than 8% of fat intake.

43. Laboratory assessment
E) Assessment of mineral deficiency
Mineral Symptoms or signs of deficiency Test
Sodium Hypovolemia, weakness - Urinary Na
Potassium Weakness, paresthesia, arrhythmia - Serum K
Magnesium Weakness, twitching, tetany,
arrhythmia, hypocalcaemia
- Serum Mg
- 24 hr. urine Mg
- Urinary Mg
Calcium Osteomalacia, tetany, arrhythmia - Serum ionized Ca
- DEXA
Phosphorous Weakness, fatigue, haemolysis,
respiratory muscle insufficiency
- Plasma P

44. Laboratory assessment
E) Assessment of mineral deficiency
Mineral Symptoms or signs of deficiency Test
Copper Anaemia, neutropenia, osteoporosis - Serum Cu
- Plasma ceruloplasmin
Iodine Hypothyroidism, goiter - Urinary I
-TSH
Iron Microcytic hypochromic anaemia - Serum Fe
-TIBC
Manganese Hypercholesterolemia, dementia,
dermatitis
- Serum Mn

45. Laboratory assessment
E) Assessment of mineral deficiency
Mineral Symptoms or signs of deficiency Test
Selenium Cardiomyopathy, myopathy,
pseudoalbinism, macrocytosis
- Serum Se
- Blood glutathione
peroxidase activity
Zinc Growth retardation, delayed sexual
maturation, alopecia, acro-orificial skin
lesion, diarrhoea, mental status changes
- Plasma Zn
- Leucocyte Zn

46. Laboratory assessment
F) Assessment of vitamin deficiency
Vitamin Symptoms or signs of deficiency Test
A (Retinol) Night blindness, Bitot’s spots,
keratomalacia, follicular
hyperkeratosis, xerosis
- Serum retinol
D (Calciferol) Rickets, osteomalacia, osteoporosis,
bone pain muscle weakness, tetany
- Serum 25-hydroxy
cholecalciferol
E (α-tocopherol) Haemolysis, retinopathy, neuropathy - Serum tocopherol
- Serum tocopherol :
total lipid ratio
K (Phylloquinone) Easy bruising and bleeding, abnormal
clotting
- Prothrombin time

47. Vitamin Symptoms or signs of deficiency Test
B1 (Thiamine) Beriberi (wet, dry),Wernicke’s
encephalopathy, fatigue, Korsakoff
psychosis
- RBC transketolase
activity
B2 (Riboflavin) Cheliosis, sore tongue and mouth, eye
irritation, seborrhoeic dermatitis
- RBC glutathione
reductase activity
B3 (Niacin) Pellagra, sore mouth and tongue - Urinary N-methyl-
nicotinamide
B5 (Pantothenic
acid)
Fatigue, weakness, paresthia,
tenderness of heels and feet
- Urinary
pantothenic acid
Laboratory assessment
F) Assessment of vitamin deficiency

48. Vitamin Symptoms or signs of deficiency Test
B6 (Pyridoxine) Seborrhoeic dermatitis, cheliosis,
glossitis, peripheral neuritis,
convulsions, hypochromic anaemia
- Plasma pyridoxal
phosphate
B7 (Biotin) Seborrhoeic dermatitis, alopecia,
change in mental status, seizures,
myalgia, hyperesthesia
- Plasma biotin
B9 (Folic acid) Megaloblastic anaemia, glossitis,
diarrhoea
- Serum folic acid
- RBC folic acid
Laboratory assessment
F) Assessment of vitamin deficiency

49. Vitamin Symptoms or signs of deficiency Test
B12
(Cyanocobolamine)
Megaloblastic anaemia, SCD,
change in mental status,
diarrhoea
- Serum cobolamine
- Serum methylmalonic
acid
C (Ascorbic acid) Scurvy, weakness, depression - Plasma ascorbic acid
- Leucocyte ascorbic
acid
Laboratory assessment
F) Assessment of vitamin deficiency

50. Measuring body composition
1) Anthropometry (weight, BMI, skinfold thickness, waist
circumference).
2) Isotope dilution.
3) Underwater weighing.
4) Bioelectrical impedance analysis (BIA).
5) Whole body counting.
6) In vivo neutron activation.
7) Dual energy X-ray absorptiometry (DEXA).
8) CT, MRI.

51. Measuring body composition
1) Isotope dilution (hydrometry)
- It is used to measure total body water, allowing estimation of
lean body mass.

52. Measuring body composition
2) Underwater weighing (hydrodensitometry, hydrostatic
weighing)
- It is used to measure body density, allowing calculation of
body fat.

53. Measuring body composition
3) Bioelectrical impedance analysis (BIA)
- Produces estimates of total body water, lean body mass and
fat mass by measuring the resistance of the body tissues to the
flow of a small electrical current.
- It is performed by applying electrodes to one arm and one leg
or by standing on a special scale.

54. Bioelectrical impedance analysis (BIA)

55. Measuring body composition
4) Whole body counting (total body potassium)
- Measures the amount of naturally radioactive potassium 40
(40K) in the body.
- Because potassium is found almost entirely intracellular,
measuring potassium can provide an estimate of body cell
mass which in turn can be used to estimate lean body mass.

56. A stand up and scanning bed
whole body counter

57. Measuring body composition
5) In vivo neutron activation analysis
- By this technique, many elements in the body can be
measured, including C, N, Na, Ca, Cl, P.
- Body nitrogen quantified by this method has been used as an
indicator of total body protein.

58. In vivo neutron activation analyzer

59. Measuring body composition
6) Dual energy X-ray absorptiometry (DEXA)
- It is developed originally for the measurement of bone density
and mass.
- It differentiates body weight into the components of lean soft
tissue, fat soft tissue and bone, based on the differential
attenuation by tissues of two levels of X-rays.

60. DEXA device

61. Measuring body composition
7) CT and MRI
- Both modalities can be used to measure the amounts of fat
and lean body tissue and their distribution and further
distinguish between intra-abdominal and extra-abdominal fat.

62. Miscellaneous tests
- Hand grip strength (hand dynamometry)
- Several studies have confirmed the importance of muscle
strength as a predictive factor for malnutrition.
- It is more useful when taken serially.