Test 8 Flashcards
factors affecting nutritional status of an individual
- quality
- quantity
- health of individual
nutritional status of the community
sum of nutritional status of individuals who form that community
objective of COMPREHENSIBLE nutritional surveys
- information about given community
- PREVALENCE of nutritional problems (how many people have it)
- geographical DISTRIBUTION of disease (where do people have it) - information leads to identification:
- at risk population (age group, sex group etc) who are at greatest need of assist
nutritional surveys - role
- collect information about nutritional disorders
- identify people who are at risk
- define the disorders and
- form the policies
purpose of nutritional assessment
- define needs of people
- develop a health care programme that meet those needs
- evaluate the progress
Nutritional surveys - SAMPLE that gives valid conclusions
- random
- representative
- cover all ages
- cover both sexes
- cover all socioeconomic classes
survey planning with aid of expert statistical advice
decisions are to be made (don’t just wing it man)
- duration
- type
- measurement techniques (standardized)
- instruments
finally -do extensive investigation on a sub sample about the nutritional status - if possible
nutritional survey
- role/ objectives - info (prevalence, distribution) - > disorders and risk groups = status assessment (define needs) -> policies formation (form programme that meet the needs and keep evaluating them)
- survey planning (duration, type, instruments, measurement kind, investigation)
- sample
types of surveys
- cross sectional
2. longitudinal
methods of nutritional assessment
evaluate - all disease stages (i.e. prepatho, patho, postpathogenesis) by under given COMPLEMENTARY methods:
- clinical examination (GPE)
- anthropometry (childhood data)
- biochemical evaluation (serum levels)
- functional assessment (bodily responses)
- assessment of dietary intake (food)
- vital and health statistics (rates, death births, marriages, divorces etc)
- ecological studies (environmental)
clinical examination
simplest
practical
look for physical signs (specific signs, non specific signs):
1. assess status of nutrition (of individual/ population)
i.e. if the person is nourished or has malnutrition:
nutritional surveys goals
- health vs food consumed
diagnosis of deficiency diseases
when two or more signs characteristic for a particular diseases are present simultaneously
classification of signs used in nutritional surveys (WHO expert committee)
- not related to nutrition
- need further investigation
- known of value
WHO classification of signs: not related to nutrition
- alopecia
- pyorrhea
3 pterygium
WHO classification of signs:: that needs further investigation
- malar pigmentation
- corneal vascularisation
- geographical tongue
WHO classification of signs: known to be of value
- angular stomatitis (deficiency of riboflavin, iron
- bitot’s spots (vitamin A deficiency)
- calf tenderness
- absence of knee or ankle jerks (beri beri)
- enlargement of thyroid gland (endemic goitre)
drawbacks of clinical signs/ examination
- malnutrition cannot be quantified
- subjectivity or lack of specificity
- some diseases aren’t associated with signs
how to overcome subjective and objective errors
- cover all parts of body in the survey (standard survey forms)
anthropometric measurements in young children
- height
- weight
- chest circumference
- arm circumference
- head circumference
- skin fold thickness
anthropometric measurements
- height
- weight
- skin fold thickness
- arm circumference
anthropometric measurements
- can be done non medical - given enough training
- record over a period of time:
- reflect pattern of growth
- reflect pattern of development
- reflects deviation from average values (of size, built and status) at various ages
natural history of disease
- prepathogenesis period
2. pathogenesis period
prepathogenesis period course
- diminishing reserves
2. reserves exhausted + physiological alteration
prepathogensis assessment methods
- food balance sheets
2. dietary surveys
pathogenesis course (+ assessment methods)
- non specific signs and symptoms (anthropometric measurements, clinical examination)
- illness (lab investigations etc)
- permanent damage (morbidity data)
- death (mortality data)
lab assessment
- blood (hemoglobin, rbc, hematocrit values)
- urine
- stool
hemoglobin assessment is the index of
- anemia
2. over all state of nutrition
stool testing is done for
intestinal parasites
Hx of infestation, diarrhea, dysentery = signify the nutritional status
urine examination is done for
- albumin
2. serum
biochemical examination - role
- precise
- detection of malnutrition in pre clinical stage by checking levels of individual nutrients or body molecules they affect
biochemical examination is done for
- vitamins in serum (retinol)
- minerals in serum (iron levels)
- enzymes for which vitamins are co factors (riboflavin is co enzyme of number of enzymes that are involved in energy metabolism eg. glutathione reductase)
- metabolites in urine (iodine)
normal iron levels of blood
0.8-1.8 mg/L
disadvantage of biochemical tests
- time consuming
- expensive
- cannot be applied on large scale (sub sample only)
- cross sectional findings
- only mild deficiencies detected
- confirmatory test for clinical assessment
currently advocated tests in nutritional surveys
- serum retinol
- TPP stimulation of RBC transketolase activity
- RBC glutathione reducatase activity stimulation by flavine adenine dinucleotide
- urine N-methyl nicotinamide
- serum folate, RBC folate
- serum B12 concentration
- leucocyte ascorbic acid
- prothrombin time
- serum albumin, serum transferrin, thyroid binding pre-albumin
biochemical tests - vitamin A
serum retinol - 20 mcg/dl
biochemical tests - thiamine
TPP stimulation of RBC transketolase activity - 1-1.23 ratio
biochemical tests - riboflavin
RBC glutathione reductase stimulation by flavine adenine dinucleotide - 1- 1.2 ratio
biochemical tests - niacin
urine N-methyl niicotinamide
biochemical tests - folate
serum folate (6 mcg/ml) rbc folate (160 mcg/ml)
biochemical tests - vitamin B12
serum B12 concentration (160 mg/ L)
biochemical tests - ascorbic acid
leucocyte ascorbic acid - 15 mcg/ 10^8 cells
biochemical tests - vitamin K
prothrombin time - 11-16 seconds
biochemical tests - protein
serum albumin - 35 g/L
serum transferrin - 20 g/L
thyroid binding pre albumin - 250 mg/L
functional indices of nutritional status / deficiencies
- structural integrity
- host defenses (P/E, Zn, Fe, Se)
- hemostasis
- reproduction
- nerve function
- work capacity
erythrocyte fragility indicates
vitamin E, selenium deficiencies
[functional indicator] state
indicates amt of deficiency
like, lesser the level of nutrient (say Se) associated with the said indicator (i.e erythrocyte fragility) is, worse is the state of that indicator (i.e. worse is the fragility)
capillary fragility indicates
vitamin C deficiency
amt of tensile strength indicates
copper levels (i.e less strength= less copper levels)
normal leucocyte chemotaxis indicates
normal P/E and Zinc levels
normal leucocyte phagocytosis indicates
normal P/E and Fe levels
normal leucocyte bacteriocidal capacity indicates
normal P/E and Fe, Se levels
normal T cell blastogenesis indicates
normal P/E and Zn levels
delayed cutaneous hypersensitivit indicates
low P/E and Zn levels
increased prothrombin time indicates
vitamin K deficiency