Transcript GP Topics - Stewart Nutrition

Nutritional Assessment
- how to do it.
April 2011
Dr Alan Stewart MB BS MRCP
www.stewartnutrition.co.uk
Nutritional Assessment
“..all doctors should be able
to diagnose nutritional
deficiencies.”
Royal College of Physicians 2002
Nutritional Assessment: What You Will Learn
1. How nutritional deficiencies develop
2. What are the common causes and effects of deficiency
3. The three key stages in Nutritional Assessment:
- history
- examination
- investigation
4. A simple method of dietary assessment
5. The prevalence of nutritional deficiencies in the UK
according to the National Diet and Nutrition Surveys
6. The importance of Nutritional Assessment
Types of Essential Nutrients
Macronutrients
• Energy - provided by Carbohydrates, Fats, Protein and Alcohol
• Protein – Essential and non-essential amino acid
Micronutrients
• Minerals:
Bulk
Trace
Ca, Mg, Na, K, Cl, P
Fe, Zn, Cu, Mn, I, Se, ? others
• Vitamins:
Fat-soluble
Water-soluble
A,D,E, and K
B group and C
• Essential Fatty Acids:
n-3 series
n-6 series
Development of a Nutritional Deficiency
Deficiencies evolve through five stages:
• Adequacy
• State of Negative Balance
• Decline in Tissue Stores
• Loss of Function
• Death
How was this arrived at?
Experimental Thiamine Deficiency
Brin M. Journal of the American Medical Association 1964;187:762-766
• Group of students volunteered for a 6 week study
• Normal diet but deficient in thiamin (<200ug/day, EAR 1000 ug)
• Test erythrocyte thiamin pyrophosphate TPP Effect – measures
increase in enzyme activity when thiamin is added to blood sample
Time in Clinical Picture
days
TPP
Effect
Dr Brin’s Term
5
None. Intake<Requirement
<1.1
Preliminary
10 -20
Fall in blood and urine levels
>1.1
Biochemical
21- 28
Fatigue, loss of appetite, nausea,
insomnia, calf pain, anxiety
1.2
Physiological
30
Ankle swelling, cardiac enlargement,
significant weight loss
1.35
Clinical
>30-300
Cardiac failure, loss of balance/coordination, mental decline
Est 1.5
Anatomical
How Do Nutritional Deficiencies Develop?
Adapted from Brin M 1964
Develop over days to years in a logical and recognizable sequence
• State of Adequacy
• State of Negative Balance
• Decline in Tissue Stores
• Loss of Function:
1. Symptoms
2. Physical Signs
3. Organ Failure
• Death
Development of a Nutritional Deficiency
•
• Adequacy
This sequence evolves over:
weeks (vitamin B1), months (zinc) or
years (calcium and vit. B12)
• State of Negative Balance: • The causes of negative balance can be
1. Poor Intake
2. Reduced Absorption
3. Increased Losses
4. Increased Demand
5. Altered Metabolism
• Decline in Tissue Stores
assessed or suspected from the history
•
Tests will assess tissue levels, but not all
deficiencies are clinically significant
•
Nutritional deficiencies are most
common at the extremes of age and
some deterioration in nutritional state is
a normal part of ageing
•
More people will have mild symptoms of
deficiency than physical signs or
complete loss of function and organ
failure
•
The clinical picture of deficiency will
depend on the loss of life function
• Loss of Function:
1. Symptoms
2. Physical Signs
3. Organ Failure
• Death
Life Functions and Nutritional Deficiency
Life Functions
Dysfunction caused by Deficiency
• Movement
Bone Fracture, Muscle Weakness
• Respiration
Early Muscle Fatigue
• Sensitivity
Neuropathy, Blindness, Reduced Intelligence
• Nutrition
Reduced ability to obtain food and feed self
• Excretion
Liver/Renal Disease
• Reproduction
Infertility, Miscarriage, Small-for-date Babies
• Growth
Infant Stunting
• Defence
Recurrent or Severe Infection
Three Methods of Nutritional Assessment
1. History
2. Physical
Examination
3. Laboratory
Investigation
The National Diet and Nutrition Surveys
• Four surveys covering ages 1.5 yrs to >85 yrs
• Random samples of the British population with
approximately 2,000 subjects in each
• Field-work conducted between 1990 and 2001
• Collected information on:
- 4-7 day weighed dietary intakes
- laboratory measures of nutrients
- alcohol intake, supplement use
- BP and BMI
• No assessment of symptoms or signs of deficiency
• The surveys provide useful information about the prevalence of
nutritional deficiencies and the associated risk factors
The Prevalence of Anaemia: NDNS
30%
Male
Female
25%
20%
15%
10%
5%
0%
1.5-2.5yr
•
•
•
•
4-6yr
15-18yr
35-49yr
75-84yr
Institution
85+yr
World Health Organisation Normal Ranges;
1.5-6.0 yrs >11.0g/dl, adult women >12.0g/dl, adult men >13.0g/dl.
Adult ranges have been adopted from ages 15yrs and upward
British laboratories often use a normal range of >11.5g/dl for adult women
Levels of 11.5-11.9g/dl in women can result in symptomatic iron deficiency
Three Methods of Nutritional Assessment
1. History
Intake: diet + supplements
Risk Factors for deficiency
Symptoms of deficiency
2. Physical
Examination
Anthropometric Measures
(Body Mass Index - kg/m2)
Signs of Deficiency
Signs of Underlying Disease
3. Laboratory
Investigation
Blood and Urine Tests
Bone Mineral Density
X-Ray
Medical Diagnosis: History is the Most Important
Nottingham 1975 W. Virginia 1992
History
82.5%
76%
Examination
8.75%
12%
Investigation
8.75%
11%
• Both studies assessed new patients, with no clear diagnosis who
were referred to a medical clinic, to determine what information was
required to reach the final diagnosis
• Hampton JR et al. BMJ. 1975;2:486-9
• Peterson MC et al. West Med J. 1992;156(2):163-5
History: Dietary Assessment - Introduction
• Not as easy (or as quick & accurate) as you might think.
• Two separate questions:
Is the diet healthy?
Is the diet adequate?
• World Health Organisation and UK Food Standards
Agency set simple but varying targets for “healthy eating”.
• Formal dietary assessment for adequacy involves:
- prospective diet diaries for several days and
- computerised analysis of macro/micronutrient intakes.
• Simple assessment is needed for use in a clinic setting
• Knowledge of the prevalence of deficiency (poor intakes
and sub-normal test results) in the British population:
National Diet and Nutrition Surveys, NDNS (1990-2003)
Healthy Eating Guidelines
Food Standards Agency 2006
World Health Organisation 2008
•
Base your meals on starchy foods
•
Eat appropriately for your weight
•
Eat appropriately for your weight
•
Fruit and Vegetables: have a good
daily intake of fresh varieties
•
Fruit and Vegetables >5 portions/day •
•
Salt <6 g/day
•
Sugar: limit intake of free sugars such
as sucrose, fructose and glucose
•
Sugar: limit intake if overweight
•
•
Saturated fats: limit intake
•
Alcohol: Weekly targets of:
<21 units for men
<14 units for women
Saturated fats: limit intake of
saturated fats which are derived
mainly from animal foods and
some tropical oils
•
Breakfast: eating it regularly helps
adherence to a healthy diet and
weight loss programme
Salt <5 g/day
Healthy Eating: EU Guidelines 2008
• Recommendations made by each country for:
- Protein-rich foods: lean meat and poultry, legumes and fish
- Dairy foods: milk/yoghurt and cheese
- Carbohydrate-rich foods: wholegrain cereals, potato and rice
- Fruit and Vegetables
• Much agreement and some disagreement
• These food groups provide approximately 2/3rds of essential
micronutrients in the British adult diet
• If an individual achieves good targets for each group then
nutritional inadequacy due to poor intake is very unlikely
• References:
Working Document on Setting Nutrient Profiles 21/10/2008
www.food.gov.uk/multimedia/pdfs/consultation/ecsettingnp.pdf
Dietary Assessment: 6 Simple Targets for Adults
Targets are adapted by the author from various sources
Food Category
Target
Protein-rich foods
>1 good portion every day
Fish*
>2 Portions/week including
>1 Oily type/week
Dairy Foods or Soya
>1.5-2 Portions/day
Fruit and Vegetables*
>5 Portions/day
Quality Carbohydrate
>1-4 Portions/day
and
Alcohol (men/women)*
<21/14 units/week
* Target set by UK Food Standards Agency
Other targets based on commonsense and other EU countries’ guidelines
Separate assessments need to be made for fats, sugar and salt
Quality Carbohydrate vs. Starchy Foods
• The UK FSA advises “base your meals on starchy foods”
• This advice does not address the problems of poor intakes of
vitamin C, folate and fibre or emphasise the benefits of wholegrain
and fibre-rich foods in reducing heart disease and cancer
• Better advice is to recommend Quality Carbohydrates:
wholegrain breakfast cereals from wheat, oats and others
wholemeal, granary and wheatmeal breads and chappati
wholemeal pasta
brown rice
fresh potatoes with their skins
• Emphasising these foods as opposed to white pasta and white rice
will improve nutrient intake for many in the UK
• The number of daily portions, typically 1-4 per day, depends on
physical activity and weight
Main Food Groups: Nutrients Provided
Food Group
Main Nutrients Provided or
Nutritional Consequences
Protein-Rich Foods
Protein, Iron, Zinc, vitamin B complex including
B12 and vitamin A if liver is consumed
Fish and Oily Fish
Protein, n-3 Essential Fatty Acids, vitamins B12
and D, and Iodine
Dairy Foods
Protein, Calcium, Iodine, Vitamin A – retinol,
Vitamins B2 and B12
Fruit and Vegetables
Potassium, Vitamin C, Folate, beta-carotene
and Fibre. Iron absorption is greatly enhanced
Quality Carbohydrates
Potassium, Magnesium, Copper, B vitamins
but not B12, and Fibre. Vitamin C from potato
Alcohol (to Excess)
Adverse effect on virtually all nutrients except
iron. Vitamin B, Zinc and Calcium deficiencies
Estimated Provision of Micronutrients by Major Food Groups
Percentages of Total Dietary Provision
Author’s estimated from NDNS of British Adults: Data collected 2000/1
Protein
Fish
Dairy
Frt & Veg
Qual CHO
Total
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
Calcium
Iron
Zinc
Folic A
Vit B12
Vit C
Estimated Provision of Micronutrients by Major Food Groups
Totals from: Proteins, Fish, Dairy Foods, Fruit and Vegetables and Quality Carbohydrates
Adults 19-64 yrs NDNS
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
Prot
Ca
Mg
K
Fe
Zn
Cu
I
Vit A
Vit C Vit B1 Vit B2 Folate
Vit
B12
n-3
EFAs
Prevalence of Poor Eating Habits in British Adults
Author’s Estimates from National Diet and Nutrition Survey 2000/1 aged 19 to 64 years
of failure to achieve 6 Healthy Eating Targets
Men
100%
Women
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
Protein
Fish and
Oily Fish
Dairy
Foods
Fruit and
Veg
Quality
Carbs
Alcohol
Defining Inadequate Nutritional Intake
• Nutritional deficiency can develop from a prolonged low intake
• UK nutrient intake requirements are set out in the report:
Dietary Reference Values for Food Energy and Nutrients for the
United Kingdom (1991 – TSO)
• The report defines The Lower Reference Nutrient Intake, LRNI, for
protein or a vitamin or mineral as “An amount of the nutrient that is
enough for only a few people in a group who have low needs”.
• In practice this means that if the percentage of a population with an
intake below the LRNI for a particular nutrient exceeds 3% then it is
likely that a significant percentage of the population will be deficient
in the nutrient
NDNS: Prevalence of Deficiency - Low Intake
Total Intakes (Food and Supplements) below LRNI for males and females
39%
36%
Calcium
33%
Potassium
30%
27%
Magnesium
24%
Iron
21%
Zinc
18%
Vitamin A
15%
12%
Vitamin B12
9%
Folate
6%
Vitamin C
3%
0%
Infants
•
•
•
Children
Adults
Free-living
Elderly
Institution
Elderly
“Lower Reference Nutrient Intake – an amount of the nutrient that is enough for only the few
people in a group who have low needs”. Considered to be <3% of the population
Prevalence rates >3% suggest that a significant percentage of the population could be deficient
Low iron intakes are observed in 33% of adult women of menstruating age
History: Dietary Assessment - Conclusions
• Formal dietary assessment is useful but time consuming
• Assess the healthfulness of a person’s diet by asking
about intake of: protein-rich foods, fish/oily fish, dairy
foods, fruit and vegetables, quality carbohydrates and
alcohol
• These groups encompass 2/3rds of micronutrient intake
• Failure to achieve a good standard for these food groups
will alert the practitioner to a possibly inadequate intake
• Separate assessments need to be made for salt, sugar
and fats
• Assess intake from nutritional supplements and be
aware of possibly excessive intake
Nutritional Assessment - Risk Factors
NICE guidelines www.nice.org.uk/cg032 (2006) and others
•
•
•
•
•
•
•
•
•
•
Fragile skin
Poor wound healing
Apathy
Wasted muscles
Poor appetite
Altered taste sensation
Impaired swallowing
Altered bowel habit
Loose fitting clothes
Prolonged intercurrent illness:
chronic infection,
chest disease,
cardiac failure,
cancer etc.
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Extremes of age
Receiving benefits
Living alone – especially men
Alcohol, tea, coffee in excess
Reduced mobility
Lack of sun exposure
Some drugs and multiple therapy
Heavy periods
History of miscarriage
Recovery from illness/operation
Pregnant or breastfeeding
Family history/genetic factors
Smoking
Inappropriate use of supplements
Nutritional Support in Adults
[www.nice.org.uk/CG032 February 2006]
Screen all patients to identify those most at risk of being deficient:
• Underweight
A body mass index (BMI) of less than 18.5kg/m2
• Unintentional weight loss
Greater than 10% within the last 3 – 6 months or
• Combination of:
BMI of less than 20kg/m2 and
Unintentional weight loss greater than 5% within the last 3 – 6 months
Others at risk:
•
•
•
Those who have eaten little or nothing for more than 5 days and/or
are likely to eat little or nothing for 5 days or longer
Those with a poor absorptive capacity and/or high nutrient losses and/or
increased nutritional needs from causes such as catabolism
Those already identified with one deficiency e.g. anaemia or osteoporosis
Prevalence of Underweight BMI <18.5 kg/m2
Adults aged 16 years and older in England, 2006. NHS Information Centre
10.00%
Men
9.00%
Women
8.00%
7.00%
6.00%
5.00%
4.00%
3.00%
2.00%
1.00%
0.00%
All
16-24
25-34
35-44
45-54
55-64
65-74
75+
Benefit Status and Micronutrient Intake
Percentage of Male Population 19-64 yrs with deficient intake, <LRNI*
51%
48%
45%
42%
39%
36%
33%
30%
27%
24%
21%
18%
15%
12%
9%
6%
3%
0%
Men No Benefits n=724
Men Benefits n=110
Vit A B1
•
•
B2
B3
B6
B12 Fol Vit C Fe
Ca
P
Mg
K
Zn
I
Data from National Diet and Nutrition Survey British Adults. TSO 2003/4
<Lower Reference Nutrient Intakes are likely to be adequate for <3% of the population.
Ref: Dietary Reference Values for Food Energy and Nutrient for the UK. HMSO 1991
Benefit Status and Micronutrient Intake
Percentage of Female Population 19-64 yrs with deficient intake, <LRNI*
51%
48%
45%
42%
39%
36%
33%
30%
27%
24%
21%
18%
15%
12%
9%
6%
3%
0%
Women No Benefits n=741
Women Benefits n=150
Vit A B1
•
•
B2
B3
B6
B12 Fol Vit C Fe
Ca
P
Mg
K
Zn
I
Data from National Diet and Nutrition Survey British Adults. TSO 2003/4
<Lower Reference Nutrient Intake are likely to be adequate for <3% of the population.
Ref: Dietary Reference Values for Food Energy and Nutrient for the UK. HMSO 1991
Influence of Household Income on Average Intake
of Nutrients in Elderly Men [NDNS 1998]
160%
<4K/yr
140%
4-6K/yr
120%
6-10K/yr
100%
>10K/yr
80%
60%
40%
20%
0%
Energy
•
•
Protein
Vitamin C
Vitamin
B12
Folate
Annual income in £000s; upper income bands are compared with lowest <4k/year
Increasing income is associated with higher intake of protein and many nutrients
Educational Attainment and Nutrient Intake (LIDNS):
% less intake if education < 5 GCSE grades A-C or equivalent
0%
-5%
-10%
-15%
-20%
Males
Females
-25%
Energy
•
•
Protein
Folate
Potassium Magnes'm
Copper
Zinc
In males energy difference significant p <0.031; all other nutrients p <0.004
In females all nutrients difference significant p <0.009
Dental Health and Nutrient Intake (LIDNS):
% difference in intake if edentate compared with dentate
35.00%
25.00%
15.00%
Males 50-64yrs
Males 65+ yrs
Females 50-64 yrs
Females 65+ yrs
5.00%
-5.00%
-15.00%
-25.00%
-35.00%
Energy
•
•
•
Protein
NSP
NMES
Vitamin C
Iron
NSP Non-starch polysaccharides; NMES Non-milk extrinsic sugars
No data on differences in intake of potassium, magnesium or folate were
presented but are likely to be similar b to but less than those for vitamin C
Data on younger age groups were not presented
Daily Alcohol Intake and Nutritional Status: NDNS 65+
% difference in status compared with non/low drinkers
Males <10g
Males 10-20g
Males =/>20g
Females <10g
Females =/>10g
50.00%
40.00%
30.00%
20.00%
10.00%
0.00%
-10.00%
-20.00%
-30.00%
Plasma
Vitamin C
•
•
•
Plasma
Vitamin D
Red Cell
Folate
Serum
Vitamin B12
Intake determined from 4 day diary
Caution, no adjustment for age, health, diet or supplements was made
Non-drinkers were more likely to be older and have abnormal liver test
History: Symptoms of Nutritional Deficiency
• Specific Symptoms
Delayed dark adaption
Sore tongue
- vitamin A or zinc
- iron, vitamin B12 and other B vitamins
• Non-specific Symptoms*
Fatigue
Cold intolerance
Loss of appetite
Poor immunity
Menstrual irregularity
Muscle cramps and pain
Numbness in feet/hands
Mood change
Cognitive decline
- anaemia, iron, potassium, magnesium,
vitamins B and C
- iron
- iron, vitamin B group and zinc
- protein, zinc, vitamins A and B
- protein, vitamin B12 and other nutrients
- potassium, magnesium and vitamin B1
- vitamins B1, 3 and B12
- vitamins C, B, folic acid and magnesium
- vitamins B12, B1 and B3, and
n-3 essential fatty acids
* Symptoms may often be due to non-nutritional causes
Examination: Signs of Nutritional Deficiency
•
Mouth
Mouth Ulcers – iron
Cracking at corners of mouth – iron, vitamin B
Dry scaley skin – Essential Fatty Acids
Easy bruising – vitamin C
Scalp hair loss – iron
Spoon-shaped nails - iron
Spinal curvature – calcium and vitamin D
Low impact fracture – calcium and vitamin D
Calf muscle tenderness – vitamin B1
Loss of strength – potassium, magnesium
Weak hip muscles – vitamin D
Clouding of the cornea – vitamin A
Loss of sensation in hands and feet – vitamins
B1, B12
Loss of vibration sense – vitamin B12
•
Skin
•
•
•
Hair
Nails
Skeleton
•
Muscle
•
•
Eyes
Neurological
•
All the above signs also have non-nutritional causes
Investigation: Laboratory Tests of Nutritional Status
• GP Tests
Full Blood Count red and white cells, platelets
Serum Ferritin or Serum Iron, Total Iron Binding Capacity + % sat
Serum Vit B12 and serum or Red Cell Folate
Plasma Na, K, vitamin D
Bone Mineral Density (Ca)
• Other Tests
Plasma elements: Zn, Cu, Se, Mn, Mg
Red cell magnesium
Vitamins B1, B2 and B6 – enzyme activation
Plasma retinol, plasma or WBC vitamin C
Urine Na, K, Iodine
• Specialised and Rare Tests
Plasma Homocysteine, MMA, Holo-transcobalamin, Enzyme tests
X-rays (vitamin D and C), Brain MRI (Mn)
Tissue levels – bone marrow, liver biopsy, post-mortem
Test Choice
Negative Balance
Poor Intake etc.
Risk Factor:
Medical or
Social
Physical Sign
The Prevalence of Anaemia: NDNS
30%
Male
Female
25%
20%
15%
10%
5%
0%
1.5-2.5yr
•
•
•
•
4-6yr
15-18yr
35-49yr
75-84yr
Institution
85+yr
World Health Organisation Normal Ranges;
1.5-6.0 yrs >11.0g/dl, adult women >12.0g/dl, adult men >13.0g/dl.
Adult ranges have been adopted from ages 15yrs and upward
British laboratories often use a normal range of >11.5g/dl for adult women
Levels of 11.5-11.9g/dl in women can result in symptomatic iron deficiency
Prevalence of Iron Deficiency: NDNS
Low Plasma Ferritin: Range < 10-20ug/l
30%
Male
Female
25%
20%
15%
10%
5%
0%
1.5-2.5yr
•
•
4-6yr
15-18yr
35-49yr
75-84yr
Inst 85+yr
Normal ranges: infants age 1.5-4.5yrs > 10.0ug/l,
females age >4yrs-adult > 15.0ug/l, males age >4yrs-adult > 20.0ug/l
Plasma ferritin can be elevated by acute or chronic inflammation, infection or
liver disease and is not a reliable measure of iron status in ill and elderly people
Prevalence of Vitamin B12 Deficiency: NDNS
Plasma <118 pmol/l
30%
Male
Female
25%
20%
15%
10%
5%
0%
1.5-2.5yr
•
•
•
4-6yr
15-18yr
35-49yr
75-84yr
Institution
85+yr
A serum vitamin B12 of 118pmol/l is equivalent to 154pg/ml
Macrocytosis (MCV >101fl) was seen in: 1-3% of teenagers, 9% of adults,
2% of free-living elderly and 3% of elderly in institutions.
Macrocytosis is often due to alcohol excess and not vitamin B12 deficiency
Prevalence of low Red Cell Folate: NDNS
Male
Female
50%
45%
40%
35%
30%
25%
20%
15%
10%
5%
0%
1.5-2.5yr
•
•
•
4-6yr
15-18yr
35-49yr
75-84yr
Institution
85+yr
The normal ranges for red cell folate and method of analysis varied with each study;
infants > 400nmol/l, children and adults > 350nmol/l and the elderly > 345nmol/l
Folate status is influenced by alcohol excess and altered metabolism in the elderly
Pregnant or breast feeding women were excluded from the adult NDNS
Prevalence of Vitamin C Deficiency
plasma Vit. C<11.0umol/l - NDNS data
Male
Female
60%
50%
40%
30%
20%
10%
0%
1.52.53.5yr 4.5yr
•
•
•
4-6yr 7-10yr
1114yr
1518yr
1924yr
2534yr
3549yr
5064yr
6574yr
7584yr
85+yr
Inst
6584yr
Inst
85+yr
Approx. 20% of adults and 12% of the elderly took supplements of vitamin C
Approx. 25% of British adults smoke and this declines after the age of 65 years
Aspirin was taken by 20% of free-living elderly and 24% of institutionalised elderly
Nutritional Deficiencies in Acutely ill Geriatric Patients:
Prevalence of Haematological Deficiencies 1973/75
100%
Age 65-70yrs (n=16)
90%
70-79yrs (n=53)
80%
80+yrs (n=24)
70%
60%
50%
40%
30%
20%
10%
0%
Anaemia
RBC Folate
Vitamin B12
% Iron Sat
•
•
•
93 acutely ill patients >65yrs: male = 35, female = 58 in Yorkshire
Folate and vitamin B12 were measured using micobiological assays
9/93 = plasma albumin >28g/l, 29/93 = plasma albumin 28-34g/l
•
Refs: Morgan AG et al. Int J Vit and Nut Research. 1973:43;46-471 & 1975:45:448-462
Vitamin Deficiencies in Acutely ill Geriatric Patients:
Prevalence of various vitamin deficiencies 1973/75
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
Age 65-70yrs (n=16)
70-79yrs (n=53)
80+yrs (n=24)
Vit A
•
•
•
PTT
TPP
Vit B2
Vit B3
WBC Vit C
93 acutely ill patients >65yrs: male = 35, female = 58
PTT = prothrombin time (Vit K), TPP = thiamin pyrophosphate effect (vit B1)
Vit B2 = whole blood riboflavin, Vit B3 = urine n-methyl nicotinamide level
References: Morgan AG et al. Int J Vit and Nut Research. 1975:45:448-462
Vitamin B Deficiencies in Newly-Admitted Psychiatric Patients
[Middlesex 1970s]
100%
Vitamin B1
90%
Vitamin B6
80%
70%
60%
50%
40%
30%
20%
10%
0%
Alc/Drug
Abuse
•
•
•
•
Schizo phrenia
Endog
Depress
Mania
Neurot
Depress
Neurosis
Organic
Psychosis
Total
154 Acute psychiatric patients with a history of poor diet: male = 52, female = 102
Vit. B1 Def = Serum Pyruvate >79umol/l (n=154), Trans Ketolase AC > 1.3 (n=74)
Vitamin B6 deficiency = Aspartate Transaminase Activation Coefficient > 1.75 (n=66)
Reference: Carney MWP et al. British Journal of Psychiatry 1979;135: 249-54
Investigation: Interpreting Nutritional Tests
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•
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There are numerous tests of nutritional status
An abnormally low result does not always mean that there is a significant
deficiency
There are essentially two types of tests:
- tests that measure the level of a nutrient
- tests that measure the function of the nutrient
Tests that measure the level of a nutrient are:
serum vitamin B12
serum ferritin (iron)
serum retinol
Corresponding test that measure the nutrient’s function are:
serum methylmalonic acid MMA (vitamin B12)
haemoglobin level
dark adaption test
Occasionally high levels of a nutrient are found
Test results must always be interpreted with knowledge of the full clinical
picture of findings from history and examination
Nutritional Assessment: Clinical Summary
• Ask about diet: type of diet and consumption of major food groups
• Ask about use of supplements
• Assess risk factors:
medical – unintentional weight loss, feeding difficulties
non-medical – socioeconomic
• Ask about symptoms of possible deficiency
• Measure BMI and examine for signs of possible deficiency
• Decide upon appropriate tests of nutritional state
• Interpret data from:
history, examination and investigation carefully
• Treat the deficiency (diet and nutrition support) and underlying
causative factors
• Monitor response to treatment
Treatment Plan
Correct
Undernutrition
Treat
Underlying Disease
or Cause
Improve/Change
Food Intake
Add in
Fortified Foods
Use Nutritional
Supplements
Nutritional Assessment: The Gold Standard
“..all doctors should be able
to diagnose nutritional
deficiencies.”
Royal College of Physicians 2002
Remember the Final Test of a Deficiency is if ..
Nutritional Assessment: Key References
You have covered
•
Nutrition is one of the essential
functions of life
•
What are the essential nutrients?
•
How do we know a nutrient is
essential?
•
How do nutritional deficiencies
develop?
•
An outline of nutrition assessment
•
What are the common nutritional
problems?
References and Further Information
Nutritional Assessment
End of Presentation
Dr Alan Stewart MB BS MRCP
www.stewartnutrition.co.uk
Nutritional Assessment: The End
Thank you for your attention
If you would like to be sent the four page handout that
accompanies this lecture or would like me to deliver the full
illustrated version of this presentation please email me at
[email protected]
Tel 01273-487003
For additional lectures see related presentations on:
National Diet and Nutrition Surveys
How Safe are Nutritional Supplements?
at www.stewartnutrition.co.uk