Concept of Health and disease

Presenter: Dr. Anil
Moderator: Dr. Chetna Maliye
 Introduction
 Changing Concept of Health
 WHO definition of health
 Positive Health
 Health Paradigm
 Determinants of Health
 Concept of Well-being
 Indicators of Health
 Concept of Disease
 Causation of disease
 Health and Illness
 Natural History of Disease
 References
 “Health “ in history
 Why we are concerned about ‘health’
 Health - Changing concepts
 Biomedical
 Ecological
 Psychological
 Holistic
Changing concepts of Health
 Biomedical Concept- “absence of disease”
 human body = machine,
 disease
= consequence of the break down
 Doctor’s task = repair of machine.
 Limitation- it has minimized the role of
environmental, social, psychological & cultural
determinants of health.
Changing concepts of Health
 Ecological Concept Health = is a dynamic equilibrium between man & his
 Disease = maladjustment of the human organisms to
the environment.
 The concept supports the need for clean air, safe
water, ozonic layer in the atmosphere, etc. to
protect us from exposure to unhealthy factors.
Changing concepts of Health
 Psychosocial Concept
 Health is not only a biomedical phenomenon, but
one which is in influenced by social psychological,
cultural, economic and political factors of the
people concerned.
Changing concepts of Health
 Holistic Concept –
 biomedical + ecological + psychosocial concept.
 It has been defined as unified or multidimensional
process involving the well being of the whole
person in the context of his environment.
 Holistic concept implies that, all sectors of society
have an effect on health
What is ‘Health’
 Oxford dictionary
 State of being well in body or mind
 Webster
 The condition of being sound in body, mind or spirit especially
freedom from physical disease or pain
 Perkins
 “A state of relative equilibrium of body, form and function which
result from its successful dynamic adjustment to forces tending
to disturb it. It is not passive interplay between body substance
and forces impinging upon it but an active response of body
forces working towards readjustment.”
WHO Definition of health
 “Health is a state of complete physical, mental and social
well-being and not merely the absence of disease or
– Constitution of the World Health Organization,
July 1946.
Physical component…
 -The state of perfect functioning of body or state in
which every cell & every organ is functioning at
optimum capacity & in perfect harmony with the rest
of the body.
Mental component Mental Health- Is a state of balance between
individual and surrounding..
 Easy to say if its grossly abnormal but difficult in
minor disturbances.
Distinction between mental and physical health is
Social component
 Social health is an aspect of health that includes social
relationships as part of broader concept of health.
 It has two elements:
 Individual and societal
 The less isolated, the greater the sense of control &
empowerment, & the more socially integrated a person
is, the less they suffer from a range of physical &
mental disorders.
Social component
 The Regional framework for health promotion in the
Western Pacific Region 2002-05 stresses the role of
social capital in health promotion.
 social capital - trust, social interaction & social
Other components/dimensions
 Spiritual
 Vocational
 Socio-economic….etc
Positive Health
 Positive health describes a state beyond the mere
absence of disease.
 Operationalised by a combination of excellent status
on biological, subjective, and functional measures
 Positive health predicts increased longevity
(correcting for quality of life), decreased health costs,
better mental health in aging, and better prognosis
when illness strikes.
Health Paradigm
Determinants of Health
Ageing of
Science &
Equity &
Concept of Well-being
Objective components
Standard of living
level of living
Subjective component
Quality of life
Standard of living
 Refers to the usual scale of our expenditure, the goods we
consume and the service we enjoy. It includes the level of
education, employment status, food, dress, house,
amusement and comforts of modern living.
 WHO: “Income & occupation, standard of housing,
sanitation and nutrition, the level of provision of health,
educational, recreational and other services.
Level of living
 Used in US
 9 Components
 Health,
 food consumption,
 education,
 occupation and working condition
 Housing,
 Social security
 Clothing
 Recreation and leisure
 Human right
Quality of life
 The condition of life resulting from the combination of
the effects of the complete range of factors such as those
determining health, happiness(including comfort in the
physical environment and the satisfying occupation),
education, social and intellectual attainments, freedom
of action, justice and freedom of expression.
 A composite measure of physical, mental and social wellbeing as perceived by each individual or group of
Indicators of Health
Physical Quality of Life Index
 Includes
 Infant mortality
 Life expectancy at age one and
 Literacy
 Scale 0 to 100 = worst to best
 ‘Money is not everything’
 Does not measure economic growth
 Measures social, economic and political policies
Human Development Index (HDI)
 Combines indicators representing 3 dimensions
1. Longevity – Life expectancy at birth
2. Knowledge – adult literacy rate & mean year of schooling.
3. Income – real GDP Per Capita in Purchasing Power
Parity(PPP) in US dollars
 Index = (Actual value) – (Minimum Value)
(Maximum value) – (Minimum Value)
Human Poverty Index
 Introduced in 1997
 Measures deprivation in basic dimensions (Longevity,
Knowledge, Income)
 For developing countries(HPI-1)A long & healthy life – vulnerability to death at a
relatively early age.
2. Knowledge – adult literacy rate
3. Standard of living – average of- %age of population not
using an improved water source & %age of children
under weight-for-age.
Concept of Disease
 “A condition in which body function is impaired,
departure from a state of health, an alteration of the
human body interrupting the performance of the vital
functions.” - Webster.
 Oxford English Dictionary – the condition of body or
some part of organ of body in which its functions are
disrupted or deranged.
 Ecologically – ‘a maladjustment of human organism to the
 Simplest definition – ‘opposite to Health’.
The Health-Sickness spectrum
Historical Theories for
causation of disease
“Supernatural causes”& Karma
Theory of humors (humor means fluid)
The miasmatic theory of disease
Theory of contagion
Germ theory
Epidemiological Triad
Multi-factorial causation
Web of causation
………Supernatural to multi-factorial causes…
Epidemiological triad
Agent Factors
Physical Agents
Chemical Agents
Biological Agents
Nutritional agents
Environmental Factors
Physical Environment
Biological Environment
Social Environment
Host Factors
Socio-demographic Factors
Psycho-social Factors
Intrinsic Characteristics
Web of causation
Change in life style
Abundance of food
Lack of physical activity
Aging &
other factor
Increase catacholamine
thrombotic activity
Coronory atherosclerosis
Coronary occlusion
Myocardial Infarction
Myocardial Infarction
Changes in walls of
Natural History of Disease
Spectrum of disease
Disease in many Forms..
 Acute
 Chronic/insidious
 Carrier
Subclinical Case: ICEBERG
Example: Cholera , Polio, hypertension, malnutrition etc.
Some terms..
 Disease- biological concept. Means
physiological/psychological dysfunction
 Illness –socio-pathological concept. Means - subjective
feeling of not being well.
 Sickness – Biological concept of social dysfunction.
WHO. Tech. Report Series 137. WHO. 1952.
WHO.Constitution Of World Health Organization. 1946.
WHO. Role of Health sector in Food and Nutrition. Tech. Report Series
137. Geneva. 1980.
IGNOU. Concepts in Nursing. Available online at:
WHO. Ageing and Health. A health promotion approach for
developing countries. WHO, Regional Office for the Western Pacific
United Nations Avenue.Manila, Philippines;2000.11-15.
Ghai OP, Gupta P. Essential Preventive Medicine. Vikas Publishing House
Pvt Ltd. India;1999:23,817-819.
Park K. Park’s textbook of preventive and social medicine. 20th
edition, 2009. Banarsidas Bhanot publishers, Jabalpur, India