Natural History of Disease

Natural History of Disease

Natural History of Disease
Referred to the course of the disease over time, unaffected by treatment. DISEASE IS AN EVOLVING PROCESS

Stages
1. Stage of Susceptibility
2. Stage of Pre-Symptomatic Disease
3. Stage of Clinical Disease
4. Stage of Disability

Stage of Susceptibility
– Disease has not developed
-Risk factors promote development (poor diet, lack of exercise, stress, high cholestorol level,etc.)
Risk Factors
Factors that will favor the disease’s development
Two types: Modifiable and Non-modifiable
Modifiable Risk factors
Changeable factors
Lifestyle: Centenarians (exercise, diet rich in fruits and vegetables, friends, purpose in life)
Obesity: Weight
Smoking: lung cancer: 2nd most common cancer
Non-modifiable factors
Factors that cannot be changed
Premature babies: at risk for mental retardation disability, chronic lung disease and learning disabilities
Age and genetics: Heart disease, Parkinson’s disease, Alzheimer’s disease
Race:
-Black Americans have higher incidence for HTN, diabetes and coronary heart disease: risk for stroke
-Mexicans have high incidence of diabetes (higher mortality)
-Native Americans have higher incidence of alcoholism, lower incidence of heart disease
Genetics
Stage of Pre-Symptomatic Disease
– No manifestations (clinical signs and symptoms) of the disease
-Pathological changes have started to occur
Examples:
-High Cholesterol: plaque formation
-High Stress Level: develop pre-hypertension
-Pre-cancerous mole: atypical cells
-Pre-diabetes: chronic elevation of blood glucose levels
Stage of Clinical Disease
-Organ changes have occured (now there are recognizeable signs and symptoms of the disease)
-Subdivided into 3 stages (Morphological, Functional or Therapeutic)
Morphological
Involves the CELLULAR level
-Most often used with CANCER
-Measures extent of disease (Ex: tumor staging)
-Allows for prognosis

Tumors placed into categories
Localized
Regional Metastasis
Metastasis

Localized
1 single lymph node or organ is involved
Regional Metastasis
Group of lymph nodes near organ on SAME SIDE of diaphragm
Metastasis
Involves BOTH SIDES of diaphragm
Functional
Involves the stages or types of disease
-Based on extent of disease
Examples
-Types of Diabetes (Insulin vs Non-Insulin dependent)
-Stages of Alzheimers (7 stages)
-Stages of Hypertension
Therapuetic
Involves the TREATMENT
-Based on restrictions
Examples
-Heart disease (Restriction of activity, dietary restrictions)
-Diabetes (Dietary or caloric restriction)
The Importance of Staging
Is for epidemiologic studies in research

Reduces variability in
-evaluation of the effect of treatments
-clinical trials
-management of clients

Stage of Disability
Any temporary or long term reduction of a person’s activities, including his psychosocial role as parent, wage earner and member of his community

Emphasis is on LOSS OF FUNCTION, not the structural defect

Examples
-Diabetes leads to blindness, amputation, renal failure or cardiac disease
-Hypertension leads to stroke and paralysis
-COPD and heart disease leads to impairment of activity

Levels of Prevention
Leavell and Clark (1965)
Disease EVOLVES over time. Pathological changes may or may not become fixed and irreversible. The aim of prevention is to DETECT and INTERVENE at the RISK FACTORS.

Basis of all prevention programs

3 Levels of Prevention
Primay Prevention
Secondary Prevention
Tertiary Prevention
Primary Prevention
-Focuses on health promotion and protection
-Occurs in the stage of SUSCEPTIBILITY
Secondary Prevention
-Identifying a health problem and its intervention
-Occurs in the stage of PRE-CLINICAL and CLINICAL
Tertiary Prevention
-Focuses on restoration and rehabilitation
-Occurs in the stage of DISABILITY
Primary Prevention (2)
Health Promotion
-AVOIDANCE of disease
-Motivated by personal approach to wellness
-WELLNESS focused

Protection against specific health problems
-Behaviors to actively avoid illness (immunizations, taking vitamins, handwashing)
-Health promotion programs (exercise programs, nutrition programs, fire safety, D.A.R.E program)

Secondary Prevention (2)
-Early identification of health problems (Goal -> identify people in early stages of disease and limit disability
-Interventions to alleviate health problems (ex: screenings, physical exam, dental checks, assessment of growth and development)
Examples:
-Annual pap smear
-Mammogram
-Self-breast exam
-Self-testicular exam
-Falls risk
-ROM
-Turn patients Q 2
Tertiary Prevention
-Begins after an illness or disability (is fixed and stabalized)
-Helps rehabilitate or restore client to optimal level of health within the constraints of the disability
Examples:
-Physical therapy
-Cardiac rehab
-Support group after cholestomy
-Teaching diabetic how to prevent complications
Schematic Representation of Natural History of Disease and Levels of Prevention (Chart)
Pg 133
Theories Used in Health Promotion
Needs Theory
Developmental Theory
Theoretical Frameworks
Needs Theory
Maslow (See pg. 134)
Needs Theory (Richard Kalish)
-Adapted Maslow’s theory (6 Levels)
-Included category between physiological and safety needs (STIMULATION NEEDS)
Developmental Stage Theory: Piaget, Erickson
-Describes characteristics of people in a certain group
Usefulness in Nursing:
-Describes a typical behavior within a certain group
-Predicts behavior in a given circumstance
-Used in clinical education
Healthy People 2010 (Purpose)
Provided framework for national health promotion, health protection and prevention
Healthy People 2010 (Goals)
-Increase quality and years of life
-Eliminate health disparities
Health (Tradition definition)
The presense or abscense of disease
Health (WHO definition)
A state of complete physical, mental and social well-being and not merely the abscense of disease and infirmity
Wellness
State of well-being
5 Models of Wellness
Clinical model
Role Performance model
Adaptive Model
Eudemonistic model
Agent-host envrironmental model
Clinical model
-PHYSIOLOGICAL aspect of health
-absence of signs and symptoms
-Disease is narrow model
Role performance model
Ability to fullfil societal’s needs
Adaptive model
-Disease is a failure in adaptation
-Aim of treatment is to restore the ability to adapt
Eudemonistic model
-Based on self-actualization (Maslow’s Theory)
-Health is seen as self-actualization
-Illness prevents actualization (client potential)
Agent-host environmental model
-Considers multiple causes of disease
-Used to predict illness
-Identifies risk factors which result from agent, host and environment
Health Illness Continua
Consists of grids or graduated scales
-Used to measure a client’s perceived level of health and illness are on opposite ends
Dunn’s High Level of Wellness Grid (See Pg. 137)
Travis’ Illness Wellness Continuum (See Pg. 138)