Topic Overview

DEFINITIONS OF HEALTH (WHO & ECOLOGICAL CONCEPT)

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WHO Definition of Health (1948)

 

 

 

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Exact Definition

• “Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.”

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Key Components

• Physical well-being
  • Normal body function
  • Absence of disease
• Mental well-being
  • Emotional stability
  • Ability to think and cope
• Social well-being
  • Ability to maintain relationships
  • Social integration

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Criticism of WHO Definition (VERY IMPORTANT)

• “Complete” is unrealistic
  • No person is completely healthy at all times
• Static concept
  • Does not consider health as a dynamic process
• Not measurable
  • Difficult to quantify “complete well-being”
• Does not include
  • Spiritual dimension
  • Environmental factors

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Modified WHO Concept (Dynamic Concept)

• Health is a dynamic state
• It is a continuous process of adaptation and adjustment
• Includes:
  • Physical
  • Mental
  • Social
  • Spiritual and environmental aspects
• Exam Line
  • Health is the ability to lead a socially and economically productive life

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Ecological Definition of Health

 

 

 

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Definition

• Health is a state of equilibrium between man and his environment

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Man–Environment Balance Concept

• Health exists when:
  • Individual is in harmony with environment
• Disease occurs when:
  • Imbalance between:
    • Host
    • Agent
    • Environment
• Closely related to:
  • Epidemiological triad

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Examples (Adaptation Failure)

• Cold exposure → hypothermia
• Heat exposure → heat stroke
• Pollution → respiratory disease
• Malnutrition → failure to adapt to nutritional demands

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⭐ Exam Quick Recall

• WHO → Complete well-being (Physical + Mental + Social)
• Criticism → Unrealistic + Static + Not measurable
• Modified concept → Dynamic + productive life
• Ecological → Balance between man & environment

 

PSYCHOSOCIAL, BIOMEDICAL & HOLISTIC CONCEPTS OF HEALTH (PSM Notes)

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Psychosocial Definition of Health

 

 

 

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Definition

• Health is influenced by interaction of social and psychological factors along with biological factors

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Role of Social + Psychological Factors

• Social factors
  • Income
  • Education
  • Occupation
  • Social support
• Psychological factors
  • Stress
  • Emotions
  • Behavior
  • Personality

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Influence of Culture & Beliefs

• Cultural practices affect:
  • Diet habits
  • Hygiene
  • Health-seeking behavior
• Beliefs influence:
  • Acceptance of treatment
  • Traditional practices

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Examples

• Stress → hypertension
• Poverty → malnutrition
• Cultural taboos → delayed treatment

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Exam Line

• Health is a product of biological + social + psychological interactions

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Biomedical Concept of Health

 

 

 

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Definition

• Health = absence of disease or infirmity

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Key Features

• Based on germ theory of disease
• Focus on:
  • Diagnosis
  • Treatment
• Emphasis on:
  • Medical care
  • Curative services

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Limitations (VERY IMPORTANT)

• Ignores:
  • Social factors
  • Psychological factors
  • Environmental factors
• Cannot explain:
  • Chronic diseases
  • Lifestyle disorders
• Narrow and incomplete concept

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Exam Line

• Biomedical model is disease-oriented, not health-oriented

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Holistic Concept of Health ⭐

 

 

 

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Definition

• Health is a multidimensional concept including all aspects of human life

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Integration of All Concepts

• Combines:
  • Biomedical (disease)
  • Psychosocial (social & mental)
  • Environmental factors

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Components

• Physical
• Mental
• Social
• Spiritual
• Emotional
• Environmental

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Modern Accepted Definition

• Health is a dynamic state of complete well-being in all dimensions

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Importance in PSM

• Basis of:
  • Preventive medicine
  • Health promotion
  • Community health
• Helps in:
  • Comprehensive patient care
  • Multisectoral approach

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Exam Line (VERY IMPORTANT)

• Holistic concept is the most accepted modern concept of health

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⭐ Quick Comparison (Exam Recall)

• Biomedical → Absence of disease
• Psychosocial → Social + psychological influence
• Holistic → Integration of all (modern concept)

 

DIMENSIONS OF HEALTH (PSM – Detailed Exam-Oriented Notes)

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Physical Dimension

 

 

 

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• Definition → Proper functioning of body systems

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Indicators

• BMI (Body Mass Index) ⭐
• Morbidity rates
• Mortality rates
• Physical fitness level

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Physical Fitness Criteria

• Strength
• Endurance
• Flexibility
• Coordination

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Mental Dimension

 

 

 

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• Definition → Ability to think, learn, and adapt

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Key Components

• Emotional stability
• Cognitive functioning
• Logical thinking

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Indicators of Mental Well-being

• Ability to cope with stress
• Absence of anxiety/depression
• Positive attitude

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Social Dimension

 

 

 

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• Definition → Ability to maintain satisfactory relationships

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Components

• Social relationships
• Community participation
• Performance of social roles

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Spiritual Dimension

 

 

 

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• Definition → Search for meaning and purpose in life

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Components

• Beliefs
• Values
• Purpose of life

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Emotional Dimension

 

 

 

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• Definition → Ability to recognize and manage emotions

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Components

• Emotional control
• Stress handling
• Expression of feelings

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Vocational Dimension

 

 

 

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• Definition → Satisfaction and fulfillment from work

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Components

• Job satisfaction
• Work-life balance
• Productivity

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Environmental Dimension

 

 

 

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• Definition → Surroundings affecting health

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Components

• Safe environment
• Pollution control
• Sanitation

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⭐ FREQUENTLY ASKED ADDITIONS

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Positive vs Negative Health

 

 

 

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Positive Health

• State of well-being and vitality
• Ability to live a productive life

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Negative Health

• Absence of disease only
• Does not imply well-being

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Exam Line

• Modern concept focuses on positive health

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Concept of Wellness

 

 

 

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• Definition →
  A dynamic process of achieving optimal health

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Key Features

• Active process
• Lifestyle-based
• Focus on prevention

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Components

• Physical fitness
• Mental peace
• Social harmony
• Healthy habits

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Exam Line

• Wellness is a continuous process, not a static state

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⭐ FINAL EXAM SUMMARY (SUPER IMPORTANT)

• Health has multiple dimensions
• WHO core → Physical, Mental, Social
• Modern → Includes spiritual, emotional, vocational, environmental
• Positive health → Well-being
• Wellness → Dynamic process

 

 

DETERMINANTS OF HEALTH ⭐ (PSM – Detailed Notes)

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Definition

 

 

 

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• Definition →
  Factors that influence the health status of an individual or population
• Key Words
  • Multifactorial
  • Interrelated
  • Dynamic

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Classification Overview (VERY IMPORTANT)

• Host (Biological) factors
• Environmental factors
• Socioeconomic factors

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1. Host Factors (Biological Factors)

 

 

 

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• These are intrinsic factors related to the individual

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Age

• Health varies with age
• Examples
  • Infants → infections, malnutrition
  • Elderly → chronic diseases
• Exam Point
  • Important determinant of morbidity and mortality

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Sex

• Biological differences affect disease pattern
• Examples
  • Females → anemia, autoimmune diseases
  • Males → higher risk of accidents, cardiovascular diseases

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Genetics (Heredity)

• Determines susceptibility to disease
• Examples
  • Diabetes mellitus
  • Hypertension
  • Hemophilia
• Exam Line
  • These are non-modifiable determinants

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2. Environmental Factors

 

 

 

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• External factors affecting health

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Types

• Physical
  • Air, water, housing, climate
• Biological
  • Bacteria, viruses, vectors
• Social
  • Culture, customs, traditions

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Examples

• Contaminated water → diarrhea
• Air pollution → COPD
• Overcrowding → TB

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Exam Line

• Major role in communicable diseases

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3. Socioeconomic Factors (MOST IMPORTANT)

 

 

 

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• Most powerful determinants of health

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Income

• Determines:
  • Nutrition
  • Housing
  • Access to healthcare
• Example
  • Poverty → malnutrition

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Education

• Improves:
  • Awareness
  • Hygiene
  • Health-seeking behavior
• Example
  • Educated mother → better child survival

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Occupation

• Influences:
  • Exposure to hazards
  • Economic status
• Examples
  • Miners → pneumoconiosis
  • Factory workers → injuries

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Exam Line

• Socioeconomic status is the strongest determinant of health

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⭐ FINAL EXAM SUMMARY

• Determinants are multifactorial
• Host → Age, sex, genetics
• Environment → Physical, biological, social
• Socioeconomic → Most important

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High-Yield MCQs

• Non-modifiable → Age, sex, genetics
• Most important → Socioeconomic factors
• Environmental → Communicable diseases

 

DETERMINANTS OF HEALTH (EXPANDED – PSM NOTES ⭐)

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1. Behavioural & Lifestyle Factors (MOST MODIFIABLE)

 

 

 

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• These are individual habits influencing health

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Diet

• Balanced diet → good health
• Malnutrition → infections, stunting
• Excess calories → obesity, diabetes

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Smoking

• Causes:
  • Lung cancer
  • COPD
  • Cardiovascular disease

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Alcohol

• Leads to:
  • Liver cirrhosis
  • Accidents
  • Mental disorders

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Physical Activity

• Regular exercise → reduces NCD risk
• Sedentary lifestyle → obesity, HTN

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Exam Line

• Lifestyle factors are the most important modifiable determinants

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2. Environmental Factors

 

 

 

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Physical Environment

• Air, water, housing, climate
• Examples
  • Air pollution → asthma
  • Unsafe water → diarrhea

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Biological Environment

• Microorganisms, vectors
• Examples
  • Mosquito → malaria
  • Bacteria → infections

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Social Environment

• Culture, customs, traditions
• Examples
  • Food habits
  • Health practices

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Exam Line

• Environmental factors are crucial in communicable diseases

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3. Socioeconomic Factors (MOST POWERFUL)

 

 

 

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Income

• Determines:
  • Nutrition
  • Living conditions
  • Healthcare access

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Poverty & Health Relation

• Poverty → malnutrition → disease → more poverty (vicious cycle)

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Education

• Improves:
  • Health awareness
  • Hygiene
  • Utilization of services

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Health Awareness

• Leads to:
  • Early diagnosis
  • Prevention

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Occupation

• Determines:
  • Income
  • Exposure to risk

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Occupational Hazards

• Dust → pneumoconiosis
• Chemicals → poisoning
• Noise → hearing loss

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Exam Line

• Socioeconomic factors are the strongest determinants of health

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4. Political System

 

 

 

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Health Policies

• Decide:
  • National health programs
  • Preventive strategies

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Resource Allocation

• Distribution of:
  • Funds
  • Infrastructure
  • Workforce

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Examples

• Immunization programs
• Ayushman Bharat

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Exam Line

• Political system determines health priorities of a country

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5. Health Services

 

 

 

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Availability

• Presence of health facilities
• Example → PHC, hospitals

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Accessibility

• Physical + financial access

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Utilization

• Actual use of services
• Example → OPD visits, immunization uptake

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Exam Line

• Effective health services improve health outcomes

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⭐ IMPORTANT ADDITIONS (VERY HIGH-YIELD)

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Dahlgren & Whitehead Model (Rainbow Model)

 

 

 

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Layers

• Innate factors → age, sex, genetics
• Individual lifestyle factors
• Social & community networks
• Living & working conditions
• General socioeconomic, cultural, environmental conditions

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Exam Line

• Demonstrates multilevel influence on health

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Concept of Social Determinants of Health

 

 

 

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• Definition
  • Conditions in which people are born, grow, live, work, and age

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Examples

• Income
• Education
• Housing
• Employment

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Importance

• Explains health inequalities
• Basis of public health planning

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Exam Line

• Social determinants are central to health equity

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⭐ FINAL EXAM SUMMARY (SUPER IMPORTANT)

• Behavioural → modifiable (most important for prevention)
• Environmental → communicable diseases
• Socioeconomic → strongest determinant
• Political → policy + resources
• Health services → availability + utilization
• Dahlgren model → layered approach
• Social determinants → health inequality concept

 

 

INDICATORS OF HEALTH ⭐ (PSM – Detailed Exam Notes)

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Introduction

 

 

 

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• Health indicators are essential tools in public health measurement
• Used for:
  • Assessing health status
  • Comparing populations
  • Planning and evaluating health services

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Definition of Indicators

• Indicators of health →
  Variables that measure and reflect the health status of a community

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Characteristics of an Ideal Indicator

• Valid → measures what it is supposed to measure
• Reliable → gives consistent results
• Sensitive → detects small changes
• Specific → reflects only the intended condition
• Feasible → easy to collect and interpret
• Relevant → useful for decision-making

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MORTALITY INDICATORS ⭐

 

 

 

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Crude Death Rate (CDR)

• Definition →
  Number of deaths per 1000 population in a year
• Formula →
  CDR = (Total deaths / Mid-year population) × 1000
• Example
  • 1000 deaths in population of 1,00,000 → CDR = 10/1000
• Note
  • Simple but least sensitive indicator

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Infant Mortality Rate (IMR) ⭐

• Definition →
  Number of deaths of children <1 year per 1000 live births
• Formula →
  IMR = (Deaths <1 year / Live births) × 1000
• Example
  • 50 infant deaths out of 2000 births → IMR = 25
• Importance
  • Most sensitive indicator of health
  • Reflects maternal & child health

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Under-5 Mortality Rate (U5MR)

• Definition →
  Number of deaths of children <5 years per 1000 live births
• Example
  • Includes infant + preschool mortality
• Importance
  • Indicator of child survival

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Maternal Mortality Ratio (MMR)

• Definition →
  Number of maternal deaths per 100,000 live births
• Formula →
  MMR = (Maternal deaths / Live births) × 100,000
• Example
  • 10 maternal deaths per 10,000 births → MMR = 100
• Importance
  • Reflects quality of obstetric care

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Life Expectancy at Birth ⭐

• Definition →
  Average number of years a newborn is expected to live
• Example
  • India ~ 69–70 years
• Importance
  • Best indicator of overall development

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Case Fatality Rate (CFR)

• Definition →
  Proportion of deaths among diagnosed cases of a disease
• Formula →
  CFR = (Deaths due to disease / Total cases of disease) × 100
• Example
  • 10 deaths out of 100 cases → CFR = 10%
• Importance
  • Indicates severity of disease

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MORBIDITY INDICATORS

 

 

 

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Incidence

• Definition →
  Number of new cases of a disease occurring in a population during a specified period
• Formula →
  Incidence = (New cases / Population at risk) × 1000 (or 100,000)
• Example
  • 100 new TB cases in 1 lakh population → incidence = 100/100,000
• Importance
  • Measures risk of developing disease

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Prevalence

• Definition →
  Total number of existing cases (new + old) in a population at a given time
• Types
  • Point prevalence
  • Period prevalence

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Formula

• Prevalence = (Total cases / Total population) × 100

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Example

• 500 total diabetes cases in 10,000 population → prevalence = 5%

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Importance

• Measures burden of disease in community

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⭐ FINAL EXAM SUMMARY (SUPER HIGH-YIELD)

• IMR → Most sensitive indicator ⭐
• Life expectancy → Best development indicator ⭐
• CFR → Severity of disease
• Incidence → New cases (risk)
• Prevalence → Total cases (burden)

 

 

INDICATORS OF HEALTH (CONTINUED – HIGH-YIELD NOTES ⭐)

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Disability Indicators

 

 

 

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DALY (Disability Adjusted Life Years) ⭐

• Definition →
  Measure of total disease burden combining:
  • Years of life lost (YLL)
  • Years lived with disability (YLD)
• Formula →
  DALY = YLL + YLD
• Example
  • Early death + years lived with illness → total burden
• Importance
  • Composite indicator
  • Used in Global Burden of Disease studies

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HALE (Health Adjusted Life Expectancy)

• Definition →
  Average number of years a person is expected to live in full health
• Key Point
  • Adjusts life expectancy by quality of health

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Nutritional Status Indicators

 

 

 

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Anthropometry

• Measurement of body dimensions
• Examples
  • Weight
  • Height
  • BMI
  • MUAC

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Clinical Signs

• Visible signs of deficiency
• Examples
  • Pallor → anemia
  • Edema → protein deficiency

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Biochemical Tests

• Laboratory investigations
• Examples
  • Hemoglobin
  • Serum proteins
  • Vitamin levels

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Health Care Delivery Indicators

 

 

 

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Doctor–Population Ratio

• Number of doctors per population
• Reflects availability of medical care

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Bed–Population Ratio

• Number of hospital beds per population
• Indicates health infrastructure

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Utilization Rates

 

 

 

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OPD Attendance

• Number of outpatient visits
• Reflects health service usage

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Hospital Admission Rate

• Number of hospital admissions
• Indicates:
  • Disease burden
  • Accessibility of services

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Social & Mental Health Indicators

 

 

 

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Suicide Rate ⭐

• Reflects mental health status

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Crime Rate

• Indicates:
  • Social instability
  • Psychosocial stress

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Environmental Indicators

 

 

 

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Air Quality

• Measured by AQI
• Linked to respiratory diseases

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Water Quality

• Safe drinking water availability
• Prevents infections

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Sanitation

• Toilet facilities, waste disposal
• Prevents communicable diseases

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Socioeconomic Indicators

 

 

 

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Literacy Rate ⭐

• Reflects:
  • Education level
  • Health awareness

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Per Capita Income

• Indicates:
  • Economic status
  • Living standards

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⭐ EXTRA HIGH-YIELD INDICATORS

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PQLI (Physical Quality of Life Index)

 

 

 

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• Components
  • Infant Mortality Rate
  • Life expectancy at age 1
  • Literacy rate
• Scale
  • 0 to 100
• Importance
  • Measures quality of life independent of income

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HDI (Human Development Index) ⭐

 

 

 

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• Components
  • Life expectancy
  • Education
  • Per capita income
• Range
  • 0 to 1
• Importance
  • Measures overall development of a country

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⭐ FINAL ULTRA REVISION (EXAM GOLD)

• DALY → Burden of disease (YLL + YLD)
• HALE → Healthy life expectancy
• IMR → Most sensitive indicator
• Life expectancy → Best development indicator
• HDI → Most used global index ⭐
• PQLI → Quality of life (IMR + literacy + life expectancy)

 

 

 

CONCEPT OF DISEASE (PSM – Exam-Oriented Notes)

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Definition of Disease

 

 

 

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Standard Definition

• Disease is a maladjustment of the human organism to the environment, resulting in functional or structural disturbances

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Disease vs Illness vs Sickness (VERY IMPORTANT)

 

 

 

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Disease

• Definition → Objective pathological condition
• Nature → Measurable and identifiable
• Example → Tuberculosis, diabetes

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Illness

• Definition → Subjective feeling of being unwell
• Nature → Patient’s perception
• Example → Fatigue, pain

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Sickness

• Definition → Social role of being ill
• Nature → Society’s recognition of illness
• Example → Leave from work, social support

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Exam Line

• Disease = objective, Illness = subjective, Sickness = social concept

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Additional Concepts

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Latent Disease

 

 

 

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• Definition → Disease present but not yet manifest clinically
• Examples
  • Latent TB
  • Incubation period of infections

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Subclinical Disease

 

 

 

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• Definition → Disease without recognizable symptoms, but detectable by tests
• Examples
  • Hypertension
  • Early diabetes

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ICEBERG PHENOMENON OF DISEASE ⭐

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Concept

 

 

 

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• Only a small proportion of cases are clinically visible
• Majority remain hidden (subclinical or undiagnosed)

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Components

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Tip of Iceberg (Visible Part)

• Clinical cases
• Diagnosed cases
• Hospitalized patients

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Submerged Part (Hidden)

• Subclinical cases
• Undiagnosed cases
• Carriers

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Diagram Explanation (VERY IMPORTANT FOR EXAM)

• Upper small portion → clinical cases
• Larger submerged portion →
  • Subclinical
  • Carriers
  • Mild/undiagnosed cases
• Exam Tip
  • Always draw a simple iceberg diagram with labeling

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Implications

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Screening Importance ⭐

• Detect hidden cases
• Early diagnosis
• Prevent complications

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Public Health Relevance

• True burden of disease is much larger than visible cases
• Important for:
  • Planning health services
  • Disease control programs

---

Examples

• Hypertension
• Diabetes
• Tuberculosis

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⭐ FINAL EXAM SUMMARY (HIGH-YIELD)

• Disease = objective, Illness = subjective, Sickness = social
• Latent → present but not expressed
• Subclinical → no symptoms but detectable
• Iceberg → hidden cases > visible cases ⭐
• Screening → key to detect submerged cases

 

 

NATURAL HISTORY OF DISEASE ⭐ (PSM – Exam-Oriented Notes)

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Definition

 

 

 

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• Natural history of disease =
  Progression of a disease from its origin to outcome in the absence of intervention

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PHASES OVERVIEW

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1. Pre-Pathogenesis Phase

 

 

 

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• Disease has not yet started in host

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Agent–Host–Environment Interaction

• Agent → bacteria, virus, toxin
• Host → age, immunity, genetics
• Environment → climate, sanitation

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Risk Factors

• Smoking
• Poor nutrition
• Unsafe water
• Genetic predisposition

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Exam Line

• Stage of disease causation without clinical disease

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2. Pathogenesis Phase

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A. Subclinical Stage

 

 

 

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• Disease has started but no symptoms

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Incubation / Latent Period

• Time between:
  • Exposure to agent
  • Appearance of symptoms

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Screening Importance ⭐

• Detect disease early
• Prevent progression
• Example:
  • BP screening
  • Blood sugar testing

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Exam Line

• Best stage for secondary prevention

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B. Clinical Stage

 

 

 

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• Disease becomes symptomatic

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Features

• Signs → objective
• Symptoms → subjective

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Stages

• Early disease
• Advanced disease

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Exam Line

• Stage where treatment is usually initiated

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3. Outcome

 

 

 

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Possible Outcomes

• Recovery
  • Complete or partial
• Disability
  • Temporary or permanent
• Death

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⭐ FLOWCHART (VERY IMPORTANT FOR EXAM)

Pre-Pathogenesis Phase
↓
Exposure to Risk Factors
↓
Pathogenesis Phase
↓ ↓
Subclinical Clinical Stage
(Incubation) (Symptoms)
↓
Outcome
(Recovery / Disability / Death)

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⭐ LEVELS OF PREVENTION CORRELATION (VERY IMPORTANT)

 

 

 

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Primary Prevention

• Acts in Pre-pathogenesis phase
• Prevent disease occurrence

Examples

• Immunization
• Health education

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Secondary Prevention

• Acts in Subclinical stage
• Early detection & treatment

Examples

• Screening programs
• Early diagnosis

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Tertiary Prevention

• Acts in Clinical stage & outcome
• Limit disability

Examples

• Rehabilitation
• Physiotherapy

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⭐ FINAL EXAM SUMMARY (SUPER HIGH-YIELD)

• Natural history = course of disease without intervention
• Pre-pathogenesis → risk factors
• Subclinical → no symptoms + screening stage ⭐
• Clinical → symptoms present
• Outcome → recovery / disability / death
• Prevention:
  • Primary → before disease
  • Secondary → early detection
  • Tertiary → rehabilitation

 

EPIDEMIOLOGICAL TRIAD ⭐ (PSM – Exam-Oriented Notes)

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Definition / Concept

 

 

 

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• Disease occurs due to interaction of three components:
  • Agent
  • Host
  • Environment
• Exam Line
  • Disease is the result of imbalance among agent, host, and environment

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COMPONENTS OF TRIAD

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1. Agent

 

 

 

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• Factor whose presence or absence causes disease

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Types of Agents

• Biological
  • Bacteria, viruses, parasites
  • Example → TB (Mycobacterium)
• Chemical
  • Toxins, pollutants
  • Example → Lead poisoning
• Physical
  • Heat, cold, radiation
  • Example → Burns
• Mechanical
  • Injury, trauma
  • Example → Road traffic accidents

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2. Host

 

 

 

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• Person who harbors the disease

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Host Factors

• Age
  • Children → infections
  • Elderly → chronic diseases
• Sex
  • Females → anemia
  • Males → accidents
• Immunity
  • Strong immunity → protection
  • Weak immunity → susceptibility
• Genetics
  • Determines disease risk

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3. Environment

 

 

 

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• External factors affecting agent and host interaction

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Types of Environment

• Physical
  • Climate, water, housing
• Biological
  • Vectors, microorganisms
• Social
  • Culture, customs, socioeconomic status

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APPLICATION IN DISEASE CAUSATION ⭐

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Concept

• Disease develops when:
  • Agent is present
  • Host is susceptible
  • Environment is favorable

---

Examples

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1. Tuberculosis

• Agent → Mycobacterium tuberculosis
• Host → Malnourished individual
• Environment → Overcrowding

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2. Malaria

• Agent → Plasmodium
• Host → Non-immune individual
• Environment → Mosquito breeding areas

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3. Road Traffic Accident

• Agent → Mechanical force
• Host → Driver
• Environment → Poor road conditions

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Public Health Importance

• Helps in:
  • Understanding disease causation
  • Planning prevention strategies
  • Identifying risk factors

---

Exam Line (VERY IMPORTANT)

• Control of disease can be achieved by:
  • Eliminating agent
  • Protecting host
  • Modifying environment

---

⭐ FINAL EXAM SUMMARY (ULTRA HIGH-YIELD)

• Triad → Agent + Host + Environment
• Agent types → biological, chemical, physical, mechanical
• Host → age, sex, immunity, genetics
• Environment → physical, biological, social
• Disease = interaction of all three ⭐

 

 

MULTIFACTORIAL CAUSATION OF DISEASE ⭐ (PSM Notes)

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Concept

 

 

 

4

• Most diseases are caused by multiple interacting factors, not a single cause
• Especially important in:
  • Chronic diseases
  • Non-communicable diseases

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Web of Causation

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Definition

• A model that explains disease as a complex interaction of multiple factors interconnected like a web

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Diagram Explanation ⭐

 

 

 

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• Central point → Disease
• Surrounding nodes → Risk factors
• Lines → Interconnections

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Examples

• Diabetes
  • Genetics
  • Obesity
  • Diet
  • Physical inactivity

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Exam Line

• No single cause → multiple interacting factors produce disease

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Risk Factors

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Definition

• Factors that increase the probability of disease occurrence

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Types

Modifiable Risk Factors

• Can be changed
• Examples:
  • Smoking
  • Diet
  • Physical inactivity

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Non-Modifiable Risk Factors

• Cannot be changed
• Examples:
  • Age
  • Sex
  • Genetics

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Exam Line

• Prevention mainly targets modifiable risk factors

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ADVANCED CONCEPTS (VERY IMPORTANT)

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Necessary Cause

• A factor that must be present for disease to occur
• Example
  • TB bacillus → tuberculosis

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Sufficient Cause

• A factor or combination of factors that inevitably produces disease
• Example
  • Combination of multiple risk factors → cancer

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Exam Line

• Most diseases are due to combination of factors (sufficient cause)

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SPECTRUM OF DISEASE ⭐

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Concept

 

 

 

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• Disease is not uniform → it exists in a range (spectrum)
• Includes:
  • Mild → severe
  • Asymptomatic → fatal

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Stages in Spectrum

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Subclinical Stage

• No symptoms
• Detectable by tests

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Clinical Stage

• Symptoms present

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Carrier State

• Harbors infection without symptoms
• Can transmit disease

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Disability

• Functional limitation

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Death

• Ultimate outcome

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Continuum Model ⭐

• Health and disease exist on a continuous scale

Health → Subclinical → Clinical → Disability → Death

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Exam Line

• Disease is a continuous process, not a single event

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⭐ FINAL EXAM SUMMARY (ULTRA HIGH-YIELD)

• Multifactorial causation → multiple interacting causes
• Web of causation → network of risk factors
• Risk factors → modifiable & non-modifiable
• Necessary cause → must be present
• Sufficient cause → combination produces disease
• Spectrum → range from subclinical to death ⭐
• Continuum → health ↔ disease is continuous

 

 

 

 

MODES OF INTERVENTION (PSM)

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Concept

 

 

 

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• Measures taken to prevent, control, or treat disease
• Three main types:
  • Medical
  • Social
  • Environmental

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1. Medical Measures

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Treatment

• Diagnosis and management of disease
• Prevents complications

Examples

• Antibiotics for infections
• Surgery

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Vaccination

• Induces immunity
• Prevents specific diseases

Examples

• BCG, DPT, COVID vaccine

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Exam Line

• Medical measures focus on individual-level intervention

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2. Social Measures

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Health Education

• Improves awareness
• Promotes healthy behavior

Examples

• Anti-smoking campaigns
• Nutrition education

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Community Participation

• Involvement of people in health programs

Examples

• Swachh Bharat
• Immunization drives

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Exam Line

• Social measures act through behavior change

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3. Environmental Measures

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Sanitation

• Safe water supply
• Waste disposal

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Vector Control

• Control of disease carriers

Examples

• Mosquito control (malaria, dengue)

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Exam Line

• Environmental control is key in communicable diseases

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CONCEPT OF WELL-BEING

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Quality of Life (QOL)

 

 

 

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Definition

• Degree of satisfaction or happiness experienced by an individual

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Indicators

• Physical health
• Mental health
• Social relationships
• Economic status

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Standard of Living (SOL)

 

 

 

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Components

• Income
• Housing
• Education
• Occupation

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Difference: QOL vs SOL ⭐

• Quality of Life
  • Subjective
  • Based on satisfaction
  • Includes mental & social aspects
• Standard of Living
  • Objective
  • Based on material conditions
  • Income-based

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Exam Line

• QOL is broader; SOL is only a part of QOL

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CHANGING CONCEPTS OF HEALTH ⭐

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Evolution of Concept

 

 

 

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Stages

1. Biomedical Concept

• Health = absence of disease

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2. Ecological Concept

• Health = balance with environment

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3. Psychosocial Concept

• Role of social + psychological factors

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4. Holistic Concept ⭐

• Integration of all dimensions

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Modern Concept of Health

• Health is:
  • Dynamic
  • Multidimensional
  • Productive

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Positive Health

• State of:
  • Well-being
  • Vitality
  • Productivity

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Wellness Concept

• Dynamic process of:
  • Achieving optimal health
  • Maintaining healthy lifestyle

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Exam Line

• Modern health concept emphasizes positive health and wellness

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⭐ FINAL ULTRA REVISION (CHAPTER END SUMMARY)

• Modes of intervention → medical, social, environmental
• QOL → subjective well-being
• SOL → material conditions
• Evolution → biomedical → ecological → psychosocial → holistic
• Modern concept → positive health + wellness ⭐