Cardiac Output, Venous Return, and Their Regulation
Â
Assessment of nutritional status
1. ASSESSMENT OF NUTRITIONAL STATUS
Prepared by : Mrs. Namita Batra Guin
Associate Professor, Community Health Nursing
INTRODUCTION
Nutrition may be defined as the science of food and its relationship to the health. It is
concerned primarily with the part played by the nutrients in the body growth, development
and maintenance. Good nutrition means âmaintaining a nutritional status that enables us to
grow well and enjoy good health.
Nutritional status is the balance between the intake of nutrients by an organism and
the expenditure of these in the processes of growth, reproduction, and health maintenance.
Because this process is highly complex and quite individualized, nutritional status assessment
can be directed at a wide variety of aspects of nutriture. These range from nutrient levels in
the body, to the products of their metabolism, and to the functional processes they regulate.
CHANGING TRENDS
History of man to a large extent has been struggle to obtain food. Until the turn of the
century the science of Nutrition had a limited range. Great advancement have been made
during last 50 years in knowledge of nutrient as in the practical application.
Specific nutritional diseases were identified and technologies are developed to control them,
as per example, protein energy malnutrition, endemic goitre, nutritional anaemia, nutritional
blindness and diarrhoeal disease. Studies of the diet and state of nutrition of people in India
showed that poorer section of population continued to suffer from malnutrition despite
increased food production.
The association of nutrition with infection, immunity, fertility, maternal and child health and
family health have engaged scientific attention. Now the nutrition has linked itself to
epidemiology and various newer concept in nutrition has come up:- epidemiological
assessment of nutritional status of communities, nutritional and dietary surveys, nutritional
surveillance, nutritional and growth monitoring, nutritional rehabilitation, nutritional
indicators and nutritional interventions â all are parts of what is broadly known as nutritional
epidemiology.
In global campaign of health for all, promotion of poorer nutrition was one of the 8
elements of primary Health Care â nutritional indicators have been developed to monitor
Health for all.
2. NUTRITIONAL ASSESSMENT
The nutritional status of an individual is often the result of many interrelated factors. It is
influenced by the adequacy of food intake both in terms of quantity and quality and also by
physical health of the individual. The nutritional status of the community is the some of the
nutritional status of the individuals who constitute the community.
Main objective of nutritional surveys is to obtain precise information on the prevalence and
geographic distribution of mal-nutrition problem of a given community and identification of
individuals or population groups âat riskâ or in the greatest need of assistance. In the absence
of this information, problem cannot be defined and policies formulated.
In nutritional surveys, it is not necessary to examine all the persons in a given community.
Examination of a random a representative sample of population covering all ages and both
sexes in different socio-economic groups is sufficient to be able to draw valid conclusions.
Purpose of Nutritional Assessment
1. Identify individuals or population groups at risk of becoming malnourished.
2. Identify individuals or population groups who are malnourished.
3. To develop health care programs that meet the community needs which are defined by
the assessment.
4. To measure the effectiveness of the nutritional programs & intervention once
initiated.
NUTRITIONAL ASSESSMENT METHODS
Nutrition is assessed by two types of methods; i.e. direct and indirect.
1. Direct methods:- The direct method deal with the individuals and measure objective
criteria.
2. Indirect methods:- The indirect method use community health indices that reflects
nutritional influences.
3. DIRECT METHOD:-
These are summarized as ABCD:-
ďˇ Anthropometric methods.
ďˇ Biochemical, laboratory methods
ďˇ Clinical methods
ďˇ Dietary evaluation methods
INDIRECT METHOD:-
These include three categories:-
ďˇ Ecological variables including crop production
ďˇ Economic factors e.g. per capital income, population density & social habits
ďˇ Vital health statistics particularly infant & under 5 mortality & fertility index.
DIRECT METHODS
1. Anthropometric method: Anthropometry is the measurement of body height, weight &
proportions. It is an essential component of clinical examination of infants, children&
pregnant women. It is used to evaluate both under & over nutrition. The measured values
reflects the current nutritional status & donât differentiate between acute & chronic changes.
Other anthropometric Measurements
ďˇ Mid-arm circumference
ďˇ Skin fold thickness
ďˇ Head circumference
ďˇ Head/chest ratio
ďˇ Hip/waist ratio
Anthropometry for children
4. ďˇ Accurate measurement of height and weight is essential. The results can then be used
to evaluate the physical growth of the child.
ďˇ For growth monitoring the data are plotted on growth charts over a period of time that
is enough to calculate growth velocity, which can then be compared to international
standards.
Anthropometry for adults
Height: The subject stands erect & bare footed on a stadiometer with a moveable head piece.
The head piece is levelled with skull vault & height is recorded to the nearest 0.5cm.
Weight:- Use a regularly calibrated electronic or balanced-beam scale. Spring scales are less
reliable. Weigh in light clothes, no shoes. Read to the nearest 100gm(0.1kg)
Nutritional indices:-
ďˇ The international standard for assessing body size in adults is the body mass index
(BMI).
ďˇ BMI is computed using the following formula:
BMI= Weight(kg)/Height(m?)
ďˇ Evidence shows that high BMI (obesity level) is associated with type 2 diabetes &
high risk of cardiovascular morbidity & mortality
BMI (WHO-classification)
BMI<18.5 = Under Weight
BMI18.5-24.5= Healthy weight range
BMI 25-30 = Overweight (grade 1 obesity)
BMI>30-40 = Obese (grade 2 obesity)
BMI>40 = Very obese(morbid or grade 3 obesity)
Waist/ Hip Ratio
5. ďˇ Waist circumference is measured at the level of the umbilicus to the nearest 0.5 cm.
ďˇ The subject stands erect with relaxed abdominal muscles, arms at the side, and feet
together.
ďˇ The measurement should be taken at the end of a normal expiration.
Waist circumference
ďˇ Waist circumference predicts mortality better than any other anthropometric
measurement. It has been proposed that waist measurement alone can be used to
assess obesity, and two levels of risk have been identified.
MALES FEMALE
LEVEL 1 >94 cm >84 cm
LEVE 2 >102 cm >88cm
ďˇ Level 1 is the maximum acceptable waist circumference is the maximum
acceptable waist circumference irrespective of the adult age and there should be
no further weight gain.
ďˇ Level 2 denotes obesity and requires weight management to reduce the risk of
type 2 diabetes & CVS complications.
Hip Circumference:-
ďˇ Is measured at the point of greatest circumference around hips & buttocks to
the nearest 0.5 cm.
ďˇ The subject should be standing and the measurer should squat beside him.
ďˇ Both measurement should taken with a flexible, non-stretchable tape in close
contact with the skin, but without indenting the soft tissue.
Interpretation of WHR:-
ďˇ High risk WHR = >0.80 for females & >0.95 for males i.e. waist
measurement > 80% of hip measurement for women and >95% for men
indicates central (upper body) obesity and is considered high risk for
diabetes & CVS disorders.
6. ďˇ A WHR below these cut-off levels is considered low risk.
ADVANTAGES OF ANTHROPOMETERY
ďˇ Objective with high specificity & sensitivity
ďˇ Measures many variables of nutritional significance(Ht,Wt, MAC,HC,
skin fold thickness, waist & hip ratio & BMI).
ďˇ Readings are numerical & gradable on standard growth charts
ďˇ Readings are reproducible.
ďˇ Non-expensive & need minimal training
LIMITATIONS OF ANTHROPOMETRY:-
ďˇ Iner-observers errors in measurement
ďˇ Limited nutritional diagnosis
ďˇ Problems with reference standards, i.e. local versus international
standards.
ďˇ Arbitrary statistical cut-off levels for what considered as abnormal
values.
2. Laboratory assessment & Bio-chemical Method
A. Laboratory Test
ďˇ Haemoglobin estimation is the most important test, & useful index of the
overall state of nutrition. Beside anemia it also tells about protein & trace
element nutrition.
ďˇ Stool examination for the presence of ova and/ or intestinal parasites
ďˇ Urine dipstick & microscopy for albumin, sugar and blood.
B. Bio-chemical Tests
ďˇ Measurement of individual nutrient in body fluids (e.g. serum, retinol, serum
iron, urinary iodine, vitamin D)
7. ďˇ Detection of abnormal amount of metabolites in the urine (e.g. urinary
creatinine/hydroxyproline ratio)
ďˇ Analysis of hair, nails & skin for micro-nutrients.
Some bio-chemical tests used in nutrition surveys:-
Nutrient Method Normal value
Vitamin A Serum retinol 20 mcg/dl
Thiamine Thiamine
pyrophosphate(TPP)
stimulation of RBC
transketolase activity
1.00-1.23(ratio)
Riboflavin RBC glutathione reductase
activity stimulated by flavine
adenine dinucleotide
1.0-1.2 ratio
Niacin Urine N-methyl nicotinamide (not very reliable)
Folate Serum folate
red cell folate
6.0 mcg/ml
160 mcg/ml
Vitamin B 12 Serum vitamin B 12
concentration
160 mg/L
Vitamin C Leucocyte ascorbic acid 15 mcg/108 cells
Vitamin K Prothrombin time 11-16 sec
Protein Serum albumin(g/L)
Transferrin(g/L)
Thyroid-binding pre-
albumin(mg/L)
35
20
250
Advantages of Biochemical Method:-
8. ďˇ It is useful in detecting early changes in body metabolism & nutrition before
the appearance of overt clinical signs.
ďˇ It is precise, accurate and reproducible.
ďˇ Useful to validate data obtained from dietary methods e.g. comparing salt
intake with 24-hour urinary excretion.
Limitation of Biochemical Method
ďˇ Time consuming
ďˇ Expensive
ďˇ They cannot be applied on large scale
ďˇ Needs trained personnel & facilities
3. Clinical Assessment: It is an essential features of all nutritional surveys. It is the simplest
& most practical method of ascertaining the nutritional status of a group of individuals. It
utilizes a number of physical signs,(specific & non specific), that are known to be associated
with malnutrition and deficiency of vitamins & micronutrients. Good nutritional history
should be obtained. General clinical examination, with special attention to organs like hair,
angles of the mouth, gums, nails, skin, eyes, tongue, muscles, bones,& thyroid gland.
Detection of relevant signs helps in establishing the nutritional diagnosis.
ADVANTAGES:-
ďˇ Fast & easy to perform
ďˇ Inexpensive
ďˇ Non-invasive
LIMITATIONS:-
ďˇ Did not detect early cases
ďˇ Many deficiencies are unaccompanied by physical signs
ďˇ Lack of specificity and subjective nature of most of the physical signs
and
ďˇ Malnutrition cannot be quantified on the basis of clinical signs.
9. CLINICAL SIGNS OF NUTRITIONAL DEFICIENCY:
HAIR
Spare & thin Protein, zinc, biotin deficiency
Easy to pull out Protein deficiency
Corkscrew Coiled hair Vit C & A deficiency
MOUTH
Glossitis Riboflavin, niacin, folic acid, B12,pr.
Bleeding & spongy gums Vit.C, A, K, folic acid & niacin
Angular stomatitis, cheilosis & fissured
tongue
B2, 6,& niacin
Leukoplakia Vit.A, B12, B-complex, folic acid &
niacin
Sore mouth & tongue Vit. B12, 6. C, niacin, folic acid & iron
EYES
Night blindness, exophthalmia Vitamin A deficiency
Photophobia-blurring, conjunctival
inflammation
Vit B2 & vit A deficiencies
NAILS
Spooning Iron deficiency
Transverse lines Protein deficiency
When two or more clinical signs characteristic of a deficiency disease are present
simultaneously, their diagnostics significance is greatly enhanced. A WHO Expert
Committee classified signs used in nutritional surveys into three categories as those:
(a) not related to nutrition, e.g. alopecia, pyorrhoea, pterygium
10. (b) that need further investigation, e.g. malar pigmentation, corneal
vascularisation, geographic tongue.
(c) known to be value, e.g., angular stomatitis, Bitotâs spots, calf tenderness,
absence of knee or ankle jerks (beri-beri), enlargement of thyroid gland
(endemic goitre), etc.
NOTE:- to minimise subjective and objective errors in clinical examination, standard survey
forms or schedules have been devised covering all areas of the body.
4. Dietary Assessment:-
Nutritional intake of humans is assessed by five different methods. These are:
i) 24 hours dietary recall
ii) Food frequency questionnaire
iii) Dietary history since early life
iv) Food dairy technique
v) Observed food consumption.
i) 24 Hours Dietary Recall:
ďˇ A trained interviewer asks the subject to recall all food & drink taken in the
previous 24 hours.
ďˇ It is quick, easy, & depends on short-term memory, but may not be truly
representative of the personâs usual intake.
ii) Food Frequency Questionnaire
ďˇ In this method the subject is given a list of around 100 food items to indicate
his or her intake(frequency & quantity) per day, per week & per month.
ďˇ Inexpensive, more representative & easy to use.
Limitations:
ďˇ Long Questionnaire
11. ďˇ Errors with estimating serving size.
ďˇ Needs updating with new commercial food products to keep pace with
changing dietary habits.
iii) Dietary History:-
ďˇ It is an accurate method for assessing the nutritional status.
ďˇ The information should be collected by a trained interviewer.
ďˇ Details about usual intake, types, amount, frequency & timing needs to be
obtained.
ďˇ Cross-checking to verify data is important.
iv) Food Dairy:-
ďˇ Food intake(types & amount) should be recorded by the subject at the time of
consumption.
ďˇ The length of the collection period range between 1-7 days.
ďˇ Reliable but difficult to maintain.
v) Observed Food Consumption:-
ďˇ The most unused method in clinical practice, but it is recommended for
research purposes.
ďˇ The meal eaten by the individual is weighed and contents are exactly
calculated.
ďˇ The method is characterized by having a high degree of accuracy but
expensive & needs time & efforts.
Interpretation of Dietary Data:-
I. Qualitative Method
ďˇ Using the food pyramid & the basic food groups method.
ďˇ Different nutrients are classified into 5 groups(fat & oils, bread & cereals,
milk products, meat-fish-poultry, vegetables & fruits)
12. ďˇ Determine the number of serving from each group & compare it with
minimum requirement.
I. Quantitative Method
ďˇ The amount of energy & specific nutrients in each food consumed can be
calculated using food composition tables & then compare it with the
recommended daily intake.
ďˇ Evaluation by this method is expensive & time consuming, unless computing
facilities are available.
INDIRECT METHODS
1. ASSESSMENT OF ECOLOGICAL FACTORS & ECONOMIC FACTORS
Malnutrition is the end result of many interacting ecological factors. A study of
ecological factors comprises the following:
ď Food balance sheet:- This is an indirect method of assessing food
consumption, in which supplies are related to census population to derive level
of food consumption in terms of per capita supply availability.
ď Socio-economic factors:- Food consumption patterns are likely to vary among
various socioeconomic groups. Family size, occupation, income, education,
custom, cultural patterns in relation to feeding practices of children and
mothers, all influence food consumption patterns.
ď Health and educational services:- Primary health care services, feeding and
immunization programs should also be taken into consideration.
ď Conditioning influences:- These include parasitic, bacterial and viral
infections which precipitate malnutrition.
It is necessary to make an âecological diagnosisâ of various factors influencing nutrition in
the community before it is possible to put into effect measures for the prevention and control
of malnutrition.
2. VITAL STATISTICS:-
13. An analysis of vital statistics mortality and morbidity data will identify groups at high
risk and indicate the extent of risk to the community. Mortality in the age group 1-4 yrs is
particularly related to malnutrition. The other rates commonly used for this purpose i.e, IMR,
rate of low birth weight babies and life- expectancy. These rates are influenced by nutritional
status and may thus be indices of nutritional status.
Data of morbidity particularly in relation to PEM, anaemia, xerophthalmia and other
vitamin deficiencies, endemic goitre, diarrhoea, measles and parasitic infestation can be of
value in providing additional information.
Bibliography:-
1. www.pitt.edu
2. www.answers.com
3. K. Park, Textbook of preventive and social medicine, 17th edition, Jabalpur, Banarasidas
Bhanot: 2003, 412, 413,444-446.
4. http://www.fao.org/3/t0807e/t0807e02.htm
5. http://ecoursesonline.iasri.res.in/mod/page/view.php?id=21129
6.https://apps.who.int/iris/bitstream/handle/10665/41780/WHO_MONO_53_%28part3%29.p
df?sequence=3&isAllowed=y